#ifndef _ASM_PROBES_H
#define _ASM_PROBES_H
+struct kprobe;
+
typedef void (kprobe_insn_handler_t)(struct kprobe *, struct pt_regs *);
typedef unsigned long (kprobe_check_cc)(unsigned long);
typedef void (kprobe_insn_singlestep_t)(struct kprobe *, struct pt_regs *);
obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o insn.o
obj-$(CONFIG_JUMP_LABEL) += jump_label.o insn.o patch.o
obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o
-obj-$(CONFIG_KPROBES) += kprobes.o kprobes-common.o patch.o
+obj-$(CONFIG_KPROBES) += probes.o kprobes.o kprobes-common.o patch.o
ifdef CONFIG_THUMB2_KERNEL
obj-$(CONFIG_KPROBES) += kprobes-thumb.o
else
-obj-$(CONFIG_KPROBES) += kprobes-arm.o
+obj-$(CONFIG_KPROBES) += kprobes-arm.o probes-arm.o
endif
obj-$(CONFIG_ARM_KPROBES_TEST) += test-kprobes.o
test-kprobes-objs := kprobes-test.o
#include <linux/kernel.h>
#include <linux/kprobes.h>
-#include <linux/module.h>
+#include <linux/ptrace.h>
#include "kprobes.h"
-
-#define sign_extend(x, signbit) ((x) | (0 - ((x) & (1 << (signbit)))))
-
-#define branch_displacement(insn) sign_extend(((insn) & 0xffffff) << 2, 25)
+#include "probes-arm.h"
#if __LINUX_ARM_ARCH__ >= 6
#define BLX(reg) "blx "reg" \n\t"
"mov pc, "reg" \n\t"
#endif
-/*
- * To avoid the complications of mimicing single-stepping on a
- * processor without a Next-PC or a single-step mode, and to
- * avoid having to deal with the side-effects of boosting, we
- * simulate or emulate (almost) all ARM instructions.
- *
- * "Simulation" is where the instruction's behavior is duplicated in
- * C code. "Emulation" is where the original instruction is rewritten
- * and executed, often by altering its registers.
- *
- * By having all behavior of the kprobe'd instruction completed before
- * returning from the kprobe_handler(), all locks (scheduler and
- * interrupt) can safely be released. There is no need for secondary
- * breakpoints, no race with MP or preemptable kernels, nor having to
- * clean up resources counts at a later time impacting overall system
- * performance. By rewriting the instruction, only the minimum registers
- * need to be loaded and saved back optimizing performance.
- *
- * Calling the insnslot_*_rwflags version of a function doesn't hurt
- * anything even when the CPSR flags aren't updated by the
- * instruction. It's just a little slower in return for saving
- * a little space by not having a duplicate function that doesn't
- * update the flags. (The same optimization can be said for
- * instructions that do or don't perform register writeback)
- * Also, instructions can either read the flags, only write the
- * flags, or read and write the flags. To save combinations
- * rather than for sheer performance, flag functions just assume
- * read and write of flags.
- */
-
-static void __kprobes simulate_bbl(struct kprobe *p, struct pt_regs *regs)
-{
- kprobe_opcode_t insn = p->opcode;
- long iaddr = (long)p->addr;
- int disp = branch_displacement(insn);
-
- if (insn & (1 << 24))
- regs->ARM_lr = iaddr + 4;
-
- regs->ARM_pc = iaddr + 8 + disp;
-}
-
-static void __kprobes simulate_blx1(struct kprobe *p, struct pt_regs *regs)
-{
- kprobe_opcode_t insn = p->opcode;
- long iaddr = (long)p->addr;
- int disp = branch_displacement(insn);
-
- regs->ARM_lr = iaddr + 4;
- regs->ARM_pc = iaddr + 8 + disp + ((insn >> 23) & 0x2);
- regs->ARM_cpsr |= PSR_T_BIT;
-}
-static void __kprobes simulate_blx2bx(struct kprobe *p, struct pt_regs *regs)
-{
- kprobe_opcode_t insn = p->opcode;
- int rm = insn & 0xf;
- long rmv = regs->uregs[rm];
-
- if (insn & (1 << 5))
- regs->ARM_lr = (long)p->addr + 4;
-
- regs->ARM_pc = rmv & ~0x1;
- regs->ARM_cpsr &= ~PSR_T_BIT;
- if (rmv & 0x1)
- regs->ARM_cpsr |= PSR_T_BIT;
-}
-
-static void __kprobes simulate_mrs(struct kprobe *p, struct pt_regs *regs)
-{
- kprobe_opcode_t insn = p->opcode;
- int rd = (insn >> 12) & 0xf;
- unsigned long mask = 0xf8ff03df; /* Mask out execution state */
- regs->uregs[rd] = regs->ARM_cpsr & mask;
-}
-
-static void __kprobes simulate_mov_ipsp(struct kprobe *p, struct pt_regs *regs)
-{
- regs->uregs[12] = regs->uregs[13];
-}
-
-static void __kprobes
+void __kprobes
emulate_ldrdstrd(struct kprobe *p, struct pt_regs *regs)
{
kprobe_opcode_t insn = p->opcode;
regs->uregs[rn] = rnv;
}
-static void __kprobes
+void __kprobes
emulate_ldr(struct kprobe *p, struct pt_regs *regs)
{
kprobe_opcode_t insn = p->opcode;
regs->uregs[rn] = rnv;
}
-static void __kprobes
+void __kprobes
emulate_str(struct kprobe *p, struct pt_regs *regs)
{
kprobe_opcode_t insn = p->opcode;
regs->uregs[rn] = rnv;
}
-static void __kprobes
+void __kprobes
emulate_rd12rn16rm0rs8_rwflags(struct kprobe *p, struct pt_regs *regs)
{
kprobe_opcode_t insn = p->opcode;
regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
}
-static void __kprobes
+void __kprobes
emulate_rd12rn16rm0_rwflags_nopc(struct kprobe *p, struct pt_regs *regs)
{
kprobe_opcode_t insn = p->opcode;
regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
}
-static void __kprobes
+void __kprobes
emulate_rd16rn12rm0rs8_rwflags_nopc(struct kprobe *p, struct pt_regs *regs)
{
kprobe_opcode_t insn = p->opcode;
regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
}
-static void __kprobes
+void __kprobes
emulate_rd12rm0_noflags_nopc(struct kprobe *p, struct pt_regs *regs)
{
kprobe_opcode_t insn = p->opcode;
regs->uregs[rd] = rdv;
}
-static void __kprobes
+void __kprobes
emulate_rdlo12rdhi16rn0rm8_rwflags_nopc(struct kprobe *p, struct pt_regs *regs)
{
kprobe_opcode_t insn = p->opcode;
regs->uregs[rdhi] = rdhiv;
regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK);
}
-
-/*
- * For the instruction masking and comparisons in all the "space_*"
- * functions below, Do _not_ rearrange the order of tests unless
- * you're very, very sure of what you are doing. For the sake of
- * efficiency, the masks for some tests sometimes assume other test
- * have been done prior to them so the number of patterns to test
- * for an instruction set can be as broad as possible to reduce the
- * number of tests needed.
- */
-
-static const union decode_item arm_1111_table[] = {
- /* Unconditional instructions */
-
- /* memory hint 1111 0100 x001 xxxx xxxx xxxx xxxx xxxx */
- /* PLDI (immediate) 1111 0100 x101 xxxx xxxx xxxx xxxx xxxx */
- /* PLDW (immediate) 1111 0101 x001 xxxx xxxx xxxx xxxx xxxx */
- /* PLD (immediate) 1111 0101 x101 xxxx xxxx xxxx xxxx xxxx */
- DECODE_SIMULATE (0xfe300000, 0xf4100000, kprobe_simulate_nop),
-
- /* memory hint 1111 0110 x001 xxxx xxxx xxxx xxx0 xxxx */
- /* PLDI (register) 1111 0110 x101 xxxx xxxx xxxx xxx0 xxxx */
- /* PLDW (register) 1111 0111 x001 xxxx xxxx xxxx xxx0 xxxx */
- /* PLD (register) 1111 0111 x101 xxxx xxxx xxxx xxx0 xxxx */
- DECODE_SIMULATE (0xfe300010, 0xf6100000, kprobe_simulate_nop),
-
- /* BLX (immediate) 1111 101x xxxx xxxx xxxx xxxx xxxx xxxx */
- DECODE_SIMULATE (0xfe000000, 0xfa000000, simulate_blx1),
-
- /* CPS 1111 0001 0000 xxx0 xxxx xxxx xx0x xxxx */
- /* SETEND 1111 0001 0000 0001 xxxx xxxx 0000 xxxx */
- /* SRS 1111 100x x1x0 xxxx xxxx xxxx xxxx xxxx */
- /* RFE 1111 100x x0x1 xxxx xxxx xxxx xxxx xxxx */
-
- /* Coprocessor instructions... */
- /* MCRR2 1111 1100 0100 xxxx xxxx xxxx xxxx xxxx */
- /* MRRC2 1111 1100 0101 xxxx xxxx xxxx xxxx xxxx */
- /* LDC2 1111 110x xxx1 xxxx xxxx xxxx xxxx xxxx */
- /* STC2 1111 110x xxx0 xxxx xxxx xxxx xxxx xxxx */
- /* CDP2 1111 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */
- /* MCR2 1111 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */
- /* MRC2 1111 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */
-
- /* Other unallocated instructions... */
- DECODE_END
-};
-
-static const union decode_item arm_cccc_0001_0xx0____0xxx_table[] = {
- /* Miscellaneous instructions */
-
- /* MRS cpsr cccc 0001 0000 xxxx xxxx xxxx 0000 xxxx */
- DECODE_SIMULATEX(0x0ff000f0, 0x01000000, simulate_mrs,
- REGS(0, NOPC, 0, 0, 0)),
-
- /* BX cccc 0001 0010 xxxx xxxx xxxx 0001 xxxx */
- DECODE_SIMULATE (0x0ff000f0, 0x01200010, simulate_blx2bx),
-
- /* BLX (register) cccc 0001 0010 xxxx xxxx xxxx 0011 xxxx */
- DECODE_SIMULATEX(0x0ff000f0, 0x01200030, simulate_blx2bx,
- REGS(0, 0, 0, 0, NOPC)),
-
- /* CLZ cccc 0001 0110 xxxx xxxx xxxx 0001 xxxx */
- DECODE_EMULATEX (0x0ff000f0, 0x01600010, emulate_rd12rm0_noflags_nopc,
- REGS(0, NOPC, 0, 0, NOPC)),
-
- /* QADD cccc 0001 0000 xxxx xxxx xxxx 0101 xxxx */
- /* QSUB cccc 0001 0010 xxxx xxxx xxxx 0101 xxxx */
- /* QDADD cccc 0001 0100 xxxx xxxx xxxx 0101 xxxx */
- /* QDSUB cccc 0001 0110 xxxx xxxx xxxx 0101 xxxx */
- DECODE_EMULATEX (0x0f9000f0, 0x01000050, emulate_rd12rn16rm0_rwflags_nopc,
- REGS(NOPC, NOPC, 0, 0, NOPC)),
-
- /* BXJ cccc 0001 0010 xxxx xxxx xxxx 0010 xxxx */
- /* MSR cccc 0001 0x10 xxxx xxxx xxxx 0000 xxxx */
- /* MRS spsr cccc 0001 0100 xxxx xxxx xxxx 0000 xxxx */
- /* BKPT 1110 0001 0010 xxxx xxxx xxxx 0111 xxxx */
- /* SMC cccc 0001 0110 xxxx xxxx xxxx 0111 xxxx */
- /* And unallocated instructions... */
- DECODE_END
-};
-
-static const union decode_item arm_cccc_0001_0xx0____1xx0_table[] = {
- /* Halfword multiply and multiply-accumulate */
-
- /* SMLALxy cccc 0001 0100 xxxx xxxx xxxx 1xx0 xxxx */
- DECODE_EMULATEX (0x0ff00090, 0x01400080, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
- REGS(NOPC, NOPC, NOPC, 0, NOPC)),
-
- /* SMULWy cccc 0001 0010 xxxx xxxx xxxx 1x10 xxxx */
- DECODE_OR (0x0ff000b0, 0x012000a0),
- /* SMULxy cccc 0001 0110 xxxx xxxx xxxx 1xx0 xxxx */
- DECODE_EMULATEX (0x0ff00090, 0x01600080, emulate_rd16rn12rm0rs8_rwflags_nopc,
- REGS(NOPC, 0, NOPC, 0, NOPC)),
-
- /* SMLAxy cccc 0001 0000 xxxx xxxx xxxx 1xx0 xxxx */
- DECODE_OR (0x0ff00090, 0x01000080),
- /* SMLAWy cccc 0001 0010 xxxx xxxx xxxx 1x00 xxxx */
- DECODE_EMULATEX (0x0ff000b0, 0x01200080, emulate_rd16rn12rm0rs8_rwflags_nopc,
- REGS(NOPC, NOPC, NOPC, 0, NOPC)),
-
- DECODE_END
-};
-
-static const union decode_item arm_cccc_0000_____1001_table[] = {
- /* Multiply and multiply-accumulate */
-
- /* MUL cccc 0000 0000 xxxx xxxx xxxx 1001 xxxx */
- /* MULS cccc 0000 0001 xxxx xxxx xxxx 1001 xxxx */
- DECODE_EMULATEX (0x0fe000f0, 0x00000090, emulate_rd16rn12rm0rs8_rwflags_nopc,
- REGS(NOPC, 0, NOPC, 0, NOPC)),
-
- /* MLA cccc 0000 0010 xxxx xxxx xxxx 1001 xxxx */
- /* MLAS cccc 0000 0011 xxxx xxxx xxxx 1001 xxxx */
- DECODE_OR (0x0fe000f0, 0x00200090),
- /* MLS cccc 0000 0110 xxxx xxxx xxxx 1001 xxxx */
- DECODE_EMULATEX (0x0ff000f0, 0x00600090, emulate_rd16rn12rm0rs8_rwflags_nopc,
- REGS(NOPC, NOPC, NOPC, 0, NOPC)),
-
- /* UMAAL cccc 0000 0100 xxxx xxxx xxxx 1001 xxxx */
- DECODE_OR (0x0ff000f0, 0x00400090),
- /* UMULL cccc 0000 1000 xxxx xxxx xxxx 1001 xxxx */
- /* UMULLS cccc 0000 1001 xxxx xxxx xxxx 1001 xxxx */
- /* UMLAL cccc 0000 1010 xxxx xxxx xxxx 1001 xxxx */
- /* UMLALS cccc 0000 1011 xxxx xxxx xxxx 1001 xxxx */
- /* SMULL cccc 0000 1100 xxxx xxxx xxxx 1001 xxxx */
- /* SMULLS cccc 0000 1101 xxxx xxxx xxxx 1001 xxxx */
- /* SMLAL cccc 0000 1110 xxxx xxxx xxxx 1001 xxxx */
- /* SMLALS cccc 0000 1111 xxxx xxxx xxxx 1001 xxxx */
- DECODE_EMULATEX (0x0f8000f0, 0x00800090, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
- REGS(NOPC, NOPC, NOPC, 0, NOPC)),
-
- DECODE_END
-};
-
-static const union decode_item arm_cccc_0001_____1001_table[] = {
- /* Synchronization primitives */
-
-#if __LINUX_ARM_ARCH__ < 6
- /* Deprecated on ARMv6 and may be UNDEFINED on v7 */
- /* SMP/SWPB cccc 0001 0x00 xxxx xxxx xxxx 1001 xxxx */
- DECODE_EMULATEX (0x0fb000f0, 0x01000090, emulate_rd12rn16rm0_rwflags_nopc,
- REGS(NOPC, NOPC, 0, 0, NOPC)),
-#endif
- /* LDREX/STREX{,D,B,H} cccc 0001 1xxx xxxx xxxx xxxx 1001 xxxx */
- /* And unallocated instructions... */
- DECODE_END
-};
-
-static const union decode_item arm_cccc_000x_____1xx1_table[] = {
- /* Extra load/store instructions */
-
- /* STRHT cccc 0000 xx10 xxxx xxxx xxxx 1011 xxxx */
- /* ??? cccc 0000 xx10 xxxx xxxx xxxx 11x1 xxxx */
- /* LDRHT cccc 0000 xx11 xxxx xxxx xxxx 1011 xxxx */
- /* LDRSBT cccc 0000 xx11 xxxx xxxx xxxx 1101 xxxx */
- /* LDRSHT cccc 0000 xx11 xxxx xxxx xxxx 1111 xxxx */
- DECODE_REJECT (0x0f200090, 0x00200090),
-
- /* LDRD/STRD lr,pc,{... cccc 000x x0x0 xxxx 111x xxxx 1101 xxxx */
- DECODE_REJECT (0x0e10e0d0, 0x0000e0d0),
-
- /* LDRD (register) cccc 000x x0x0 xxxx xxxx xxxx 1101 xxxx */
- /* STRD (register) cccc 000x x0x0 xxxx xxxx xxxx 1111 xxxx */
- DECODE_EMULATEX (0x0e5000d0, 0x000000d0, emulate_ldrdstrd,
- REGS(NOPCWB, NOPCX, 0, 0, NOPC)),
-
- /* LDRD (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1101 xxxx */
- /* STRD (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1111 xxxx */
- DECODE_EMULATEX (0x0e5000d0, 0x004000d0, emulate_ldrdstrd,
- REGS(NOPCWB, NOPCX, 0, 0, 0)),
-
- /* STRH (register) cccc 000x x0x0 xxxx xxxx xxxx 1011 xxxx */
- DECODE_EMULATEX (0x0e5000f0, 0x000000b0, emulate_str,
- REGS(NOPCWB, NOPC, 0, 0, NOPC)),
-
- /* LDRH (register) cccc 000x x0x1 xxxx xxxx xxxx 1011 xxxx */
- /* LDRSB (register) cccc 000x x0x1 xxxx xxxx xxxx 1101 xxxx */
- /* LDRSH (register) cccc 000x x0x1 xxxx xxxx xxxx 1111 xxxx */
- DECODE_EMULATEX (0x0e500090, 0x00100090, emulate_ldr,
- REGS(NOPCWB, NOPC, 0, 0, NOPC)),
-
- /* STRH (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1011 xxxx */
- DECODE_EMULATEX (0x0e5000f0, 0x004000b0, emulate_str,
- REGS(NOPCWB, NOPC, 0, 0, 0)),
-
- /* LDRH (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1011 xxxx */
- /* LDRSB (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1101 xxxx */
- /* LDRSH (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1111 xxxx */
- DECODE_EMULATEX (0x0e500090, 0x00500090, emulate_ldr,
- REGS(NOPCWB, NOPC, 0, 0, 0)),
-
- DECODE_END
-};
-
-static const union decode_item arm_cccc_000x_table[] = {
- /* Data-processing (register) */
-
- /* <op>S PC, ... cccc 000x xxx1 xxxx 1111 xxxx xxxx xxxx */
- DECODE_REJECT (0x0e10f000, 0x0010f000),
-
- /* MOV IP, SP 1110 0001 1010 0000 1100 0000 0000 1101 */
- DECODE_SIMULATE (0xffffffff, 0xe1a0c00d, simulate_mov_ipsp),
-
- /* TST (register) cccc 0001 0001 xxxx xxxx xxxx xxx0 xxxx */
- /* TEQ (register) cccc 0001 0011 xxxx xxxx xxxx xxx0 xxxx */
- /* CMP (register) cccc 0001 0101 xxxx xxxx xxxx xxx0 xxxx */
- /* CMN (register) cccc 0001 0111 xxxx xxxx xxxx xxx0 xxxx */
- DECODE_EMULATEX (0x0f900010, 0x01100000, emulate_rd12rn16rm0rs8_rwflags,
- REGS(ANY, 0, 0, 0, ANY)),
-
- /* MOV (register) cccc 0001 101x xxxx xxxx xxxx xxx0 xxxx */
- /* MVN (register) cccc 0001 111x xxxx xxxx xxxx xxx0 xxxx */
- DECODE_EMULATEX (0x0fa00010, 0x01a00000, emulate_rd12rn16rm0rs8_rwflags,
- REGS(0, ANY, 0, 0, ANY)),
-
- /* AND (register) cccc 0000 000x xxxx xxxx xxxx xxx0 xxxx */
- /* EOR (register) cccc 0000 001x xxxx xxxx xxxx xxx0 xxxx */
- /* SUB (register) cccc 0000 010x xxxx xxxx xxxx xxx0 xxxx */
- /* RSB (register) cccc 0000 011x xxxx xxxx xxxx xxx0 xxxx */
- /* ADD (register) cccc 0000 100x xxxx xxxx xxxx xxx0 xxxx */
- /* ADC (register) cccc 0000 101x xxxx xxxx xxxx xxx0 xxxx */
- /* SBC (register) cccc 0000 110x xxxx xxxx xxxx xxx0 xxxx */
- /* RSC (register) cccc 0000 111x xxxx xxxx xxxx xxx0 xxxx */
- /* ORR (register) cccc 0001 100x xxxx xxxx xxxx xxx0 xxxx */
- /* BIC (register) cccc 0001 110x xxxx xxxx xxxx xxx0 xxxx */
- DECODE_EMULATEX (0x0e000010, 0x00000000, emulate_rd12rn16rm0rs8_rwflags,
- REGS(ANY, ANY, 0, 0, ANY)),
-
- /* TST (reg-shift reg) cccc 0001 0001 xxxx xxxx xxxx 0xx1 xxxx */
- /* TEQ (reg-shift reg) cccc 0001 0011 xxxx xxxx xxxx 0xx1 xxxx */
- /* CMP (reg-shift reg) cccc 0001 0101 xxxx xxxx xxxx 0xx1 xxxx */
- /* CMN (reg-shift reg) cccc 0001 0111 xxxx xxxx xxxx 0xx1 xxxx */
- DECODE_EMULATEX (0x0f900090, 0x01100010, emulate_rd12rn16rm0rs8_rwflags,
- REGS(ANY, 0, NOPC, 0, ANY)),
-
- /* MOV (reg-shift reg) cccc 0001 101x xxxx xxxx xxxx 0xx1 xxxx */
- /* MVN (reg-shift reg) cccc 0001 111x xxxx xxxx xxxx 0xx1 xxxx */
- DECODE_EMULATEX (0x0fa00090, 0x01a00010, emulate_rd12rn16rm0rs8_rwflags,
- REGS(0, ANY, NOPC, 0, ANY)),
-
- /* AND (reg-shift reg) cccc 0000 000x xxxx xxxx xxxx 0xx1 xxxx */
- /* EOR (reg-shift reg) cccc 0000 001x xxxx xxxx xxxx 0xx1 xxxx */
- /* SUB (reg-shift reg) cccc 0000 010x xxxx xxxx xxxx 0xx1 xxxx */
- /* RSB (reg-shift reg) cccc 0000 011x xxxx xxxx xxxx 0xx1 xxxx */
- /* ADD (reg-shift reg) cccc 0000 100x xxxx xxxx xxxx 0xx1 xxxx */
- /* ADC (reg-shift reg) cccc 0000 101x xxxx xxxx xxxx 0xx1 xxxx */
- /* SBC (reg-shift reg) cccc 0000 110x xxxx xxxx xxxx 0xx1 xxxx */
- /* RSC (reg-shift reg) cccc 0000 111x xxxx xxxx xxxx 0xx1 xxxx */
- /* ORR (reg-shift reg) cccc 0001 100x xxxx xxxx xxxx 0xx1 xxxx */
- /* BIC (reg-shift reg) cccc 0001 110x xxxx xxxx xxxx 0xx1 xxxx */
- DECODE_EMULATEX (0x0e000090, 0x00000010, emulate_rd12rn16rm0rs8_rwflags,
- REGS(ANY, ANY, NOPC, 0, ANY)),
-
- DECODE_END
-};
-
-static const union decode_item arm_cccc_001x_table[] = {
- /* Data-processing (immediate) */
-
- /* MOVW cccc 0011 0000 xxxx xxxx xxxx xxxx xxxx */
- /* MOVT cccc 0011 0100 xxxx xxxx xxxx xxxx xxxx */
- DECODE_EMULATEX (0x0fb00000, 0x03000000, emulate_rd12rm0_noflags_nopc,
- REGS(0, NOPC, 0, 0, 0)),
-
- /* YIELD cccc 0011 0010 0000 xxxx xxxx 0000 0001 */
- DECODE_OR (0x0fff00ff, 0x03200001),
- /* SEV cccc 0011 0010 0000 xxxx xxxx 0000 0100 */
- DECODE_EMULATE (0x0fff00ff, 0x03200004, kprobe_emulate_none),
- /* NOP cccc 0011 0010 0000 xxxx xxxx 0000 0000 */
- /* WFE cccc 0011 0010 0000 xxxx xxxx 0000 0010 */
- /* WFI cccc 0011 0010 0000 xxxx xxxx 0000 0011 */
- DECODE_SIMULATE (0x0fff00fc, 0x03200000, kprobe_simulate_nop),
- /* DBG cccc 0011 0010 0000 xxxx xxxx ffff xxxx */
- /* unallocated hints cccc 0011 0010 0000 xxxx xxxx xxxx xxxx */
- /* MSR (immediate) cccc 0011 0x10 xxxx xxxx xxxx xxxx xxxx */
- DECODE_REJECT (0x0fb00000, 0x03200000),
-
- /* <op>S PC, ... cccc 001x xxx1 xxxx 1111 xxxx xxxx xxxx */
- DECODE_REJECT (0x0e10f000, 0x0210f000),
-
- /* TST (immediate) cccc 0011 0001 xxxx xxxx xxxx xxxx xxxx */
- /* TEQ (immediate) cccc 0011 0011 xxxx xxxx xxxx xxxx xxxx */
- /* CMP (immediate) cccc 0011 0101 xxxx xxxx xxxx xxxx xxxx */
- /* CMN (immediate) cccc 0011 0111 xxxx xxxx xxxx xxxx xxxx */
- DECODE_EMULATEX (0x0f900000, 0x03100000, emulate_rd12rn16rm0rs8_rwflags,
- REGS(ANY, 0, 0, 0, 0)),
-
- /* MOV (immediate) cccc 0011 101x xxxx xxxx xxxx xxxx xxxx */
- /* MVN (immediate) cccc 0011 111x xxxx xxxx xxxx xxxx xxxx */
- DECODE_EMULATEX (0x0fa00000, 0x03a00000, emulate_rd12rn16rm0rs8_rwflags,
- REGS(0, ANY, 0, 0, 0)),
-
- /* AND (immediate) cccc 0010 000x xxxx xxxx xxxx xxxx xxxx */
- /* EOR (immediate) cccc 0010 001x xxxx xxxx xxxx xxxx xxxx */
- /* SUB (immediate) cccc 0010 010x xxxx xxxx xxxx xxxx xxxx */
- /* RSB (immediate) cccc 0010 011x xxxx xxxx xxxx xxxx xxxx */
- /* ADD (immediate) cccc 0010 100x xxxx xxxx xxxx xxxx xxxx */
- /* ADC (immediate) cccc 0010 101x xxxx xxxx xxxx xxxx xxxx */
- /* SBC (immediate) cccc 0010 110x xxxx xxxx xxxx xxxx xxxx */
- /* RSC (immediate) cccc 0010 111x xxxx xxxx xxxx xxxx xxxx */
- /* ORR (immediate) cccc 0011 100x xxxx xxxx xxxx xxxx xxxx */
- /* BIC (immediate) cccc 0011 110x xxxx xxxx xxxx xxxx xxxx */
- DECODE_EMULATEX (0x0e000000, 0x02000000, emulate_rd12rn16rm0rs8_rwflags,
- REGS(ANY, ANY, 0, 0, 0)),
-
- DECODE_END
-};
-
-static const union decode_item arm_cccc_0110_____xxx1_table[] = {
- /* Media instructions */
-
- /* SEL cccc 0110 1000 xxxx xxxx xxxx 1011 xxxx */
- DECODE_EMULATEX (0x0ff000f0, 0x068000b0, emulate_rd12rn16rm0_rwflags_nopc,
- REGS(NOPC, NOPC, 0, 0, NOPC)),
-
- /* SSAT cccc 0110 101x xxxx xxxx xxxx xx01 xxxx */
- /* USAT cccc 0110 111x xxxx xxxx xxxx xx01 xxxx */
- DECODE_OR(0x0fa00030, 0x06a00010),
- /* SSAT16 cccc 0110 1010 xxxx xxxx xxxx 0011 xxxx */
- /* USAT16 cccc 0110 1110 xxxx xxxx xxxx 0011 xxxx */
- DECODE_EMULATEX (0x0fb000f0, 0x06a00030, emulate_rd12rn16rm0_rwflags_nopc,
- REGS(0, NOPC, 0, 0, NOPC)),
-
- /* REV cccc 0110 1011 xxxx xxxx xxxx 0011 xxxx */
- /* REV16 cccc 0110 1011 xxxx xxxx xxxx 1011 xxxx */
- /* RBIT cccc 0110 1111 xxxx xxxx xxxx 0011 xxxx */
- /* REVSH cccc 0110 1111 xxxx xxxx xxxx 1011 xxxx */
- DECODE_EMULATEX (0x0fb00070, 0x06b00030, emulate_rd12rm0_noflags_nopc,
- REGS(0, NOPC, 0, 0, NOPC)),
-
- /* ??? cccc 0110 0x00 xxxx xxxx xxxx xxx1 xxxx */
- DECODE_REJECT (0x0fb00010, 0x06000010),
- /* ??? cccc 0110 0xxx xxxx xxxx xxxx 1011 xxxx */
- DECODE_REJECT (0x0f8000f0, 0x060000b0),
- /* ??? cccc 0110 0xxx xxxx xxxx xxxx 1101 xxxx */
- DECODE_REJECT (0x0f8000f0, 0x060000d0),
- /* SADD16 cccc 0110 0001 xxxx xxxx xxxx 0001 xxxx */
- /* SADDSUBX cccc 0110 0001 xxxx xxxx xxxx 0011 xxxx */
- /* SSUBADDX cccc 0110 0001 xxxx xxxx xxxx 0101 xxxx */
- /* SSUB16 cccc 0110 0001 xxxx xxxx xxxx 0111 xxxx */
- /* SADD8 cccc 0110 0001 xxxx xxxx xxxx 1001 xxxx */
- /* SSUB8 cccc 0110 0001 xxxx xxxx xxxx 1111 xxxx */
- /* QADD16 cccc 0110 0010 xxxx xxxx xxxx 0001 xxxx */
- /* QADDSUBX cccc 0110 0010 xxxx xxxx xxxx 0011 xxxx */
- /* QSUBADDX cccc 0110 0010 xxxx xxxx xxxx 0101 xxxx */
- /* QSUB16 cccc 0110 0010 xxxx xxxx xxxx 0111 xxxx */
- /* QADD8 cccc 0110 0010 xxxx xxxx xxxx 1001 xxxx */
- /* QSUB8 cccc 0110 0010 xxxx xxxx xxxx 1111 xxxx */
- /* SHADD16 cccc 0110 0011 xxxx xxxx xxxx 0001 xxxx */
- /* SHADDSUBX cccc 0110 0011 xxxx xxxx xxxx 0011 xxxx */
- /* SHSUBADDX cccc 0110 0011 xxxx xxxx xxxx 0101 xxxx */
- /* SHSUB16 cccc 0110 0011 xxxx xxxx xxxx 0111 xxxx */
- /* SHADD8 cccc 0110 0011 xxxx xxxx xxxx 1001 xxxx */
- /* SHSUB8 cccc 0110 0011 xxxx xxxx xxxx 1111 xxxx */
- /* UADD16 cccc 0110 0101 xxxx xxxx xxxx 0001 xxxx */
- /* UADDSUBX cccc 0110 0101 xxxx xxxx xxxx 0011 xxxx */
- /* USUBADDX cccc 0110 0101 xxxx xxxx xxxx 0101 xxxx */
- /* USUB16 cccc 0110 0101 xxxx xxxx xxxx 0111 xxxx */
- /* UADD8 cccc 0110 0101 xxxx xxxx xxxx 1001 xxxx */
- /* USUB8 cccc 0110 0101 xxxx xxxx xxxx 1111 xxxx */
- /* UQADD16 cccc 0110 0110 xxxx xxxx xxxx 0001 xxxx */
- /* UQADDSUBX cccc 0110 0110 xxxx xxxx xxxx 0011 xxxx */
- /* UQSUBADDX cccc 0110 0110 xxxx xxxx xxxx 0101 xxxx */
- /* UQSUB16 cccc 0110 0110 xxxx xxxx xxxx 0111 xxxx */
- /* UQADD8 cccc 0110 0110 xxxx xxxx xxxx 1001 xxxx */
- /* UQSUB8 cccc 0110 0110 xxxx xxxx xxxx 1111 xxxx */
- /* UHADD16 cccc 0110 0111 xxxx xxxx xxxx 0001 xxxx */
- /* UHADDSUBX cccc 0110 0111 xxxx xxxx xxxx 0011 xxxx */
- /* UHSUBADDX cccc 0110 0111 xxxx xxxx xxxx 0101 xxxx */
- /* UHSUB16 cccc 0110 0111 xxxx xxxx xxxx 0111 xxxx */
- /* UHADD8 cccc 0110 0111 xxxx xxxx xxxx 1001 xxxx */
- /* UHSUB8 cccc 0110 0111 xxxx xxxx xxxx 1111 xxxx */
- DECODE_EMULATEX (0x0f800010, 0x06000010, emulate_rd12rn16rm0_rwflags_nopc,
- REGS(NOPC, NOPC, 0, 0, NOPC)),
-
- /* PKHBT cccc 0110 1000 xxxx xxxx xxxx x001 xxxx */
- /* PKHTB cccc 0110 1000 xxxx xxxx xxxx x101 xxxx */
- DECODE_EMULATEX (0x0ff00030, 0x06800010, emulate_rd12rn16rm0_rwflags_nopc,
- REGS(NOPC, NOPC, 0, 0, NOPC)),
-
- /* ??? cccc 0110 1001 xxxx xxxx xxxx 0111 xxxx */
- /* ??? cccc 0110 1101 xxxx xxxx xxxx 0111 xxxx */
- DECODE_REJECT (0x0fb000f0, 0x06900070),
-
- /* SXTB16 cccc 0110 1000 1111 xxxx xxxx 0111 xxxx */
- /* SXTB cccc 0110 1010 1111 xxxx xxxx 0111 xxxx */
- /* SXTH cccc 0110 1011 1111 xxxx xxxx 0111 xxxx */
- /* UXTB16 cccc 0110 1100 1111 xxxx xxxx 0111 xxxx */
- /* UXTB cccc 0110 1110 1111 xxxx xxxx 0111 xxxx */
- /* UXTH cccc 0110 1111 1111 xxxx xxxx 0111 xxxx */
- DECODE_EMULATEX (0x0f8f00f0, 0x068f0070, emulate_rd12rm0_noflags_nopc,
- REGS(0, NOPC, 0, 0, NOPC)),
-
- /* SXTAB16 cccc 0110 1000 xxxx xxxx xxxx 0111 xxxx */
- /* SXTAB cccc 0110 1010 xxxx xxxx xxxx 0111 xxxx */
- /* SXTAH cccc 0110 1011 xxxx xxxx xxxx 0111 xxxx */
- /* UXTAB16 cccc 0110 1100 xxxx xxxx xxxx 0111 xxxx */
- /* UXTAB cccc 0110 1110 xxxx xxxx xxxx 0111 xxxx */
- /* UXTAH cccc 0110 1111 xxxx xxxx xxxx 0111 xxxx */
- DECODE_EMULATEX (0x0f8000f0, 0x06800070, emulate_rd12rn16rm0_rwflags_nopc,
- REGS(NOPCX, NOPC, 0, 0, NOPC)),
-
- DECODE_END
-};
-
-static const union decode_item arm_cccc_0111_____xxx1_table[] = {
- /* Media instructions */
-
- /* UNDEFINED cccc 0111 1111 xxxx xxxx xxxx 1111 xxxx */
- DECODE_REJECT (0x0ff000f0, 0x07f000f0),
-
- /* SMLALD cccc 0111 0100 xxxx xxxx xxxx 00x1 xxxx */
- /* SMLSLD cccc 0111 0100 xxxx xxxx xxxx 01x1 xxxx */
- DECODE_EMULATEX (0x0ff00090, 0x07400010, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
- REGS(NOPC, NOPC, NOPC, 0, NOPC)),
-
- /* SMUAD cccc 0111 0000 xxxx 1111 xxxx 00x1 xxxx */
- /* SMUSD cccc 0111 0000 xxxx 1111 xxxx 01x1 xxxx */
- DECODE_OR (0x0ff0f090, 0x0700f010),
- /* SMMUL cccc 0111 0101 xxxx 1111 xxxx 00x1 xxxx */
- DECODE_OR (0x0ff0f0d0, 0x0750f010),
- /* USAD8 cccc 0111 1000 xxxx 1111 xxxx 0001 xxxx */
- DECODE_EMULATEX (0x0ff0f0f0, 0x0780f010, emulate_rd16rn12rm0rs8_rwflags_nopc,
- REGS(NOPC, 0, NOPC, 0, NOPC)),
-
- /* SMLAD cccc 0111 0000 xxxx xxxx xxxx 00x1 xxxx */
- /* SMLSD cccc 0111 0000 xxxx xxxx xxxx 01x1 xxxx */
- DECODE_OR (0x0ff00090, 0x07000010),
- /* SMMLA cccc 0111 0101 xxxx xxxx xxxx 00x1 xxxx */
- DECODE_OR (0x0ff000d0, 0x07500010),
- /* USADA8 cccc 0111 1000 xxxx xxxx xxxx 0001 xxxx */
- DECODE_EMULATEX (0x0ff000f0, 0x07800010, emulate_rd16rn12rm0rs8_rwflags_nopc,
- REGS(NOPC, NOPCX, NOPC, 0, NOPC)),
-
- /* SMMLS cccc 0111 0101 xxxx xxxx xxxx 11x1 xxxx */
- DECODE_EMULATEX (0x0ff000d0, 0x075000d0, emulate_rd16rn12rm0rs8_rwflags_nopc,
- REGS(NOPC, NOPC, NOPC, 0, NOPC)),
-
- /* SBFX cccc 0111 101x xxxx xxxx xxxx x101 xxxx */
- /* UBFX cccc 0111 111x xxxx xxxx xxxx x101 xxxx */
- DECODE_EMULATEX (0x0fa00070, 0x07a00050, emulate_rd12rm0_noflags_nopc,
- REGS(0, NOPC, 0, 0, NOPC)),
-
- /* BFC cccc 0111 110x xxxx xxxx xxxx x001 1111 */
- DECODE_EMULATEX (0x0fe0007f, 0x07c0001f, emulate_rd12rm0_noflags_nopc,
- REGS(0, NOPC, 0, 0, 0)),
-
- /* BFI cccc 0111 110x xxxx xxxx xxxx x001 xxxx */
- DECODE_EMULATEX (0x0fe00070, 0x07c00010, emulate_rd12rm0_noflags_nopc,
- REGS(0, NOPC, 0, 0, NOPCX)),
-
- DECODE_END
-};
-
-static const union decode_item arm_cccc_01xx_table[] = {
- /* Load/store word and unsigned byte */
-
- /* LDRB/STRB pc,[...] cccc 01xx x0xx xxxx xxxx xxxx xxxx xxxx */
- DECODE_REJECT (0x0c40f000, 0x0440f000),
-
- /* STRT cccc 01x0 x010 xxxx xxxx xxxx xxxx xxxx */
- /* LDRT cccc 01x0 x011 xxxx xxxx xxxx xxxx xxxx */
- /* STRBT cccc 01x0 x110 xxxx xxxx xxxx xxxx xxxx */
- /* LDRBT cccc 01x0 x111 xxxx xxxx xxxx xxxx xxxx */
- DECODE_REJECT (0x0d200000, 0x04200000),
-
- /* STR (immediate) cccc 010x x0x0 xxxx xxxx xxxx xxxx xxxx */
- /* STRB (immediate) cccc 010x x1x0 xxxx xxxx xxxx xxxx xxxx */
- DECODE_EMULATEX (0x0e100000, 0x04000000, emulate_str,
- REGS(NOPCWB, ANY, 0, 0, 0)),
-
- /* LDR (immediate) cccc 010x x0x1 xxxx xxxx xxxx xxxx xxxx */
- /* LDRB (immediate) cccc 010x x1x1 xxxx xxxx xxxx xxxx xxxx */
- DECODE_EMULATEX (0x0e100000, 0x04100000, emulate_ldr,
- REGS(NOPCWB, ANY, 0, 0, 0)),
-
- /* STR (register) cccc 011x x0x0 xxxx xxxx xxxx xxxx xxxx */
- /* STRB (register) cccc 011x x1x0 xxxx xxxx xxxx xxxx xxxx */
- DECODE_EMULATEX (0x0e100000, 0x06000000, emulate_str,
- REGS(NOPCWB, ANY, 0, 0, NOPC)),
-
- /* LDR (register) cccc 011x x0x1 xxxx xxxx xxxx xxxx xxxx */
- /* LDRB (register) cccc 011x x1x1 xxxx xxxx xxxx xxxx xxxx */
- DECODE_EMULATEX (0x0e100000, 0x06100000, emulate_ldr,
- REGS(NOPCWB, ANY, 0, 0, NOPC)),
-
- DECODE_END
-};
-
-static const union decode_item arm_cccc_100x_table[] = {
- /* Block data transfer instructions */
-
- /* LDM cccc 100x x0x1 xxxx xxxx xxxx xxxx xxxx */
- /* STM cccc 100x x0x0 xxxx xxxx xxxx xxxx xxxx */
- DECODE_CUSTOM (0x0e400000, 0x08000000, kprobe_decode_ldmstm),
-
- /* STM (user registers) cccc 100x x1x0 xxxx xxxx xxxx xxxx xxxx */
- /* LDM (user registers) cccc 100x x1x1 xxxx 0xxx xxxx xxxx xxxx */
- /* LDM (exception ret) cccc 100x x1x1 xxxx 1xxx xxxx xxxx xxxx */
- DECODE_END
-};
-
-const union decode_item kprobe_decode_arm_table[] = {
- /*
- * Unconditional instructions
- * 1111 xxxx xxxx xxxx xxxx xxxx xxxx xxxx
- */
- DECODE_TABLE (0xf0000000, 0xf0000000, arm_1111_table),
-
- /*
- * Miscellaneous instructions
- * cccc 0001 0xx0 xxxx xxxx xxxx 0xxx xxxx
- */
- DECODE_TABLE (0x0f900080, 0x01000000, arm_cccc_0001_0xx0____0xxx_table),
-
- /*
- * Halfword multiply and multiply-accumulate
- * cccc 0001 0xx0 xxxx xxxx xxxx 1xx0 xxxx
- */
- DECODE_TABLE (0x0f900090, 0x01000080, arm_cccc_0001_0xx0____1xx0_table),
-
- /*
- * Multiply and multiply-accumulate
- * cccc 0000 xxxx xxxx xxxx xxxx 1001 xxxx
- */
- DECODE_TABLE (0x0f0000f0, 0x00000090, arm_cccc_0000_____1001_table),
-
- /*
- * Synchronization primitives
- * cccc 0001 xxxx xxxx xxxx xxxx 1001 xxxx
- */
- DECODE_TABLE (0x0f0000f0, 0x01000090, arm_cccc_0001_____1001_table),
-
- /*
- * Extra load/store instructions
- * cccc 000x xxxx xxxx xxxx xxxx 1xx1 xxxx
- */
- DECODE_TABLE (0x0e000090, 0x00000090, arm_cccc_000x_____1xx1_table),
-
- /*
- * Data-processing (register)
- * cccc 000x xxxx xxxx xxxx xxxx xxx0 xxxx
- * Data-processing (register-shifted register)
- * cccc 000x xxxx xxxx xxxx xxxx 0xx1 xxxx
- */
- DECODE_TABLE (0x0e000000, 0x00000000, arm_cccc_000x_table),
-
- /*
- * Data-processing (immediate)
- * cccc 001x xxxx xxxx xxxx xxxx xxxx xxxx
- */
- DECODE_TABLE (0x0e000000, 0x02000000, arm_cccc_001x_table),
-
- /*
- * Media instructions
- * cccc 011x xxxx xxxx xxxx xxxx xxx1 xxxx
- */
- DECODE_TABLE (0x0f000010, 0x06000010, arm_cccc_0110_____xxx1_table),
- DECODE_TABLE (0x0f000010, 0x07000010, arm_cccc_0111_____xxx1_table),
-
- /*
- * Load/store word and unsigned byte
- * cccc 01xx xxxx xxxx xxxx xxxx xxxx xxxx
- */
- DECODE_TABLE (0x0c000000, 0x04000000, arm_cccc_01xx_table),
-
- /*
- * Block data transfer instructions
- * cccc 100x xxxx xxxx xxxx xxxx xxxx xxxx
- */
- DECODE_TABLE (0x0e000000, 0x08000000, arm_cccc_100x_table),
-
- /* B cccc 1010 xxxx xxxx xxxx xxxx xxxx xxxx */
- /* BL cccc 1011 xxxx xxxx xxxx xxxx xxxx xxxx */
- DECODE_SIMULATE (0x0e000000, 0x0a000000, simulate_bbl),
-
- /*
- * Supervisor Call, and coprocessor instructions
- */
-
- /* MCRR cccc 1100 0100 xxxx xxxx xxxx xxxx xxxx */
- /* MRRC cccc 1100 0101 xxxx xxxx xxxx xxxx xxxx */
- /* LDC cccc 110x xxx1 xxxx xxxx xxxx xxxx xxxx */
- /* STC cccc 110x xxx0 xxxx xxxx xxxx xxxx xxxx */
- /* CDP cccc 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */
- /* MCR cccc 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */
- /* MRC cccc 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */
- /* SVC cccc 1111 xxxx xxxx xxxx xxxx xxxx xxxx */
- DECODE_REJECT (0x0c000000, 0x0c000000),
-
- DECODE_END
-};
-#ifdef CONFIG_ARM_KPROBES_TEST_MODULE
-EXPORT_SYMBOL_GPL(kprobe_decode_arm_table);
-#endif
-
-static void __kprobes arm_singlestep(struct kprobe *p, struct pt_regs *regs)
-{
- regs->ARM_pc += 4;
- p->ainsn.insn_handler(p, regs);
-}
-
-/* Return:
- * INSN_REJECTED If instruction is one not allowed to kprobe,
- * INSN_GOOD If instruction is supported and uses instruction slot,
- * INSN_GOOD_NO_SLOT If instruction is supported but doesn't use its slot.
- *
- * For instructions we don't want to kprobe (INSN_REJECTED return result):
- * These are generally ones that modify the processor state making
- * them "hard" to simulate such as switches processor modes or
- * make accesses in alternate modes. Any of these could be simulated
- * if the work was put into it, but low return considering they
- * should also be very rare.
- */
-enum kprobe_insn __kprobes
-arm_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi)
-{
- asi->insn_singlestep = arm_singlestep;
- asi->insn_check_cc = kprobe_condition_checks[insn>>28];
- return kprobe_decode_insn(insn, asi, kprobe_decode_arm_table, false);
-}
#include <linux/kernel.h>
#include <linux/kprobes.h>
-#include <asm/system_info.h>
-#include <linux/types.h>
-#include <linux/stddef.h>
-#include <linux/bug.h>
#include "kprobes.h"
-#ifndef find_str_pc_offset
-
-/*
- * For STR and STM instructions, an ARM core may choose to use either
- * a +8 or a +12 displacement from the current instruction's address.
- * Whichever value is chosen for a given core, it must be the same for
- * both instructions and may not change. This function measures it.
- */
-
-int str_pc_offset;
-
-void __init find_str_pc_offset(void)
-{
- int addr, scratch, ret;
-
- __asm__ (
- "sub %[ret], pc, #4 \n\t"
- "str pc, %[addr] \n\t"
- "ldr %[scr], %[addr] \n\t"
- "sub %[ret], %[scr], %[ret] \n\t"
- : [ret] "=r" (ret), [scr] "=r" (scratch), [addr] "+m" (addr));
-
- str_pc_offset = ret;
-}
-
-#endif /* !find_str_pc_offset */
-
-
-#ifndef test_load_write_pc_interworking
-
-bool load_write_pc_interworks;
-
-void __init test_load_write_pc_interworking(void)
-{
- int arch = cpu_architecture();
- BUG_ON(arch == CPU_ARCH_UNKNOWN);
- load_write_pc_interworks = arch >= CPU_ARCH_ARMv5T;
-}
-
-#endif /* !test_load_write_pc_interworking */
-
-
-#ifndef test_alu_write_pc_interworking
-
-bool alu_write_pc_interworks;
-
-void __init test_alu_write_pc_interworking(void)
-{
- int arch = cpu_architecture();
- BUG_ON(arch == CPU_ARCH_UNKNOWN);
- alu_write_pc_interworks = arch >= CPU_ARCH_ARMv7;
-}
-
-#endif /* !test_alu_write_pc_interworking */
-
-
-void __init arm_kprobe_decode_init(void)
-{
- find_str_pc_offset();
- test_load_write_pc_interworking();
- test_alu_write_pc_interworking();
-}
-
-
-static unsigned long __kprobes __check_eq(unsigned long cpsr)
-{
- return cpsr & PSR_Z_BIT;
-}
-
-static unsigned long __kprobes __check_ne(unsigned long cpsr)
-{
- return (~cpsr) & PSR_Z_BIT;
-}
-
-static unsigned long __kprobes __check_cs(unsigned long cpsr)
-{
- return cpsr & PSR_C_BIT;
-}
-
-static unsigned long __kprobes __check_cc(unsigned long cpsr)
-{
- return (~cpsr) & PSR_C_BIT;
-}
-
-static unsigned long __kprobes __check_mi(unsigned long cpsr)
-{
- return cpsr & PSR_N_BIT;
-}
-
-static unsigned long __kprobes __check_pl(unsigned long cpsr)
-{
- return (~cpsr) & PSR_N_BIT;
-}
-
-static unsigned long __kprobes __check_vs(unsigned long cpsr)
-{
- return cpsr & PSR_V_BIT;
-}
-
-static unsigned long __kprobes __check_vc(unsigned long cpsr)
-{
- return (~cpsr) & PSR_V_BIT;
-}
-
-static unsigned long __kprobes __check_hi(unsigned long cpsr)
-{
- cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
- return cpsr & PSR_C_BIT;
-}
-
-static unsigned long __kprobes __check_ls(unsigned long cpsr)
-{
- cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
- return (~cpsr) & PSR_C_BIT;
-}
-
-static unsigned long __kprobes __check_ge(unsigned long cpsr)
-{
- cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
- return (~cpsr) & PSR_N_BIT;
-}
-
-static unsigned long __kprobes __check_lt(unsigned long cpsr)
-{
- cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
- return cpsr & PSR_N_BIT;
-}
-
-static unsigned long __kprobes __check_gt(unsigned long cpsr)
-{
- unsigned long temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
- temp |= (cpsr << 1); /* PSR_N_BIT |= PSR_Z_BIT */
- return (~temp) & PSR_N_BIT;
-}
-
-static unsigned long __kprobes __check_le(unsigned long cpsr)
-{
- unsigned long temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
- temp |= (cpsr << 1); /* PSR_N_BIT |= PSR_Z_BIT */
- return temp & PSR_N_BIT;
-}
-
-static unsigned long __kprobes __check_al(unsigned long cpsr)
-{
- return true;
-}
-
-kprobe_check_cc * const kprobe_condition_checks[16] = {
- &__check_eq, &__check_ne, &__check_cs, &__check_cc,
- &__check_mi, &__check_pl, &__check_vs, &__check_vc,
- &__check_hi, &__check_ls, &__check_ge, &__check_lt,
- &__check_gt, &__check_le, &__check_al, &__check_al
-};
-
-
-void __kprobes kprobe_simulate_nop(struct kprobe *p, struct pt_regs *regs)
-{
-}
-
-void __kprobes kprobe_emulate_none(struct kprobe *p, struct pt_regs *regs)
-{
- p->ainsn.insn_fn();
-}
-
static void __kprobes simulate_ldm1stm1(struct kprobe *p, struct pt_regs *regs)
{
kprobe_opcode_t insn = p->opcode;
return INSN_GOOD_NO_SLOT;
}
-
-/*
- * Prepare an instruction slot to receive an instruction for emulating.
- * This is done by placing a subroutine return after the location where the
- * instruction will be placed. We also modify ARM instructions to be
- * unconditional as the condition code will already be checked before any
- * emulation handler is called.
- */
-static kprobe_opcode_t __kprobes
-prepare_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi,
- bool thumb)
-{
-#ifdef CONFIG_THUMB2_KERNEL
- if (thumb) {
- u16 *thumb_insn = (u16 *)asi->insn;
- thumb_insn[1] = 0x4770; /* Thumb bx lr */
- thumb_insn[2] = 0x4770; /* Thumb bx lr */
- return insn;
- }
- asi->insn[1] = 0xe12fff1e; /* ARM bx lr */
-#else
- asi->insn[1] = 0xe1a0f00e; /* mov pc, lr */
-#endif
- /* Make an ARM instruction unconditional */
- if (insn < 0xe0000000)
- insn = (insn | 0xe0000000) & ~0x10000000;
- return insn;
-}
-
-/*
- * Write a (probably modified) instruction into the slot previously prepared by
- * prepare_emulated_insn
- */
-static void __kprobes
-set_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi,
- bool thumb)
-{
-#ifdef CONFIG_THUMB2_KERNEL
- if (thumb) {
- u16 *ip = (u16 *)asi->insn;
- if (is_wide_instruction(insn))
- *ip++ = insn >> 16;
- *ip++ = insn;
- return;
- }
-#endif
- asi->insn[0] = insn;
-}
-
-/*
- * When we modify the register numbers encoded in an instruction to be emulated,
- * the new values come from this define. For ARM and 32-bit Thumb instructions
- * this gives...
- *
- * bit position 16 12 8 4 0
- * ---------------+---+---+---+---+---+
- * register r2 r0 r1 -- r3
- */
-#define INSN_NEW_BITS 0x00020103
-
-/* Each nibble has same value as that at INSN_NEW_BITS bit 16 */
-#define INSN_SAMEAS16_BITS 0x22222222
-
-/*
- * Validate and modify each of the registers encoded in an instruction.
- *
- * Each nibble in regs contains a value from enum decode_reg_type. For each
- * non-zero value, the corresponding nibble in pinsn is validated and modified
- * according to the type.
- */
-static bool __kprobes decode_regs(kprobe_opcode_t* pinsn, u32 regs)
-{
- kprobe_opcode_t insn = *pinsn;
- kprobe_opcode_t mask = 0xf; /* Start at least significant nibble */
-
- for (; regs != 0; regs >>= 4, mask <<= 4) {
-
- kprobe_opcode_t new_bits = INSN_NEW_BITS;
-
- switch (regs & 0xf) {
-
- case REG_TYPE_NONE:
- /* Nibble not a register, skip to next */
- continue;
-
- case REG_TYPE_ANY:
- /* Any register is allowed */
- break;
-
- case REG_TYPE_SAMEAS16:
- /* Replace register with same as at bit position 16 */
- new_bits = INSN_SAMEAS16_BITS;
- break;
-
- case REG_TYPE_SP:
- /* Only allow SP (R13) */
- if ((insn ^ 0xdddddddd) & mask)
- goto reject;
- break;
-
- case REG_TYPE_PC:
- /* Only allow PC (R15) */
- if ((insn ^ 0xffffffff) & mask)
- goto reject;
- break;
-
- case REG_TYPE_NOSP:
- /* Reject SP (R13) */
- if (((insn ^ 0xdddddddd) & mask) == 0)
- goto reject;
- break;
-
- case REG_TYPE_NOSPPC:
- case REG_TYPE_NOSPPCX:
- /* Reject SP and PC (R13 and R15) */
- if (((insn ^ 0xdddddddd) & 0xdddddddd & mask) == 0)
- goto reject;
- break;
-
- case REG_TYPE_NOPCWB:
- if (!is_writeback(insn))
- break; /* No writeback, so any register is OK */
- /* fall through... */
- case REG_TYPE_NOPC:
- case REG_TYPE_NOPCX:
- /* Reject PC (R15) */
- if (((insn ^ 0xffffffff) & mask) == 0)
- goto reject;
- break;
- }
-
- /* Replace value of nibble with new register number... */
- insn &= ~mask;
- insn |= new_bits & mask;
- }
-
- *pinsn = insn;
- return true;
-
-reject:
- return false;
-}
-
-static const int decode_struct_sizes[NUM_DECODE_TYPES] = {
- [DECODE_TYPE_TABLE] = sizeof(struct decode_table),
- [DECODE_TYPE_CUSTOM] = sizeof(struct decode_custom),
- [DECODE_TYPE_SIMULATE] = sizeof(struct decode_simulate),
- [DECODE_TYPE_EMULATE] = sizeof(struct decode_emulate),
- [DECODE_TYPE_OR] = sizeof(struct decode_or),
- [DECODE_TYPE_REJECT] = sizeof(struct decode_reject)
-};
-
-/*
- * kprobe_decode_insn operates on data tables in order to decode an ARM
- * architecture instruction onto which a kprobe has been placed.
- *
- * These instruction decoding tables are a concatenation of entries each
- * of which consist of one of the following structs:
- *
- * decode_table
- * decode_custom
- * decode_simulate
- * decode_emulate
- * decode_or
- * decode_reject
- *
- * Each of these starts with a struct decode_header which has the following
- * fields:
- *
- * type_regs
- * mask
- * value
- *
- * The least significant DECODE_TYPE_BITS of type_regs contains a value
- * from enum decode_type, this indicates which of the decode_* structs
- * the entry contains. The value DECODE_TYPE_END indicates the end of the
- * table.
- *
- * When the table is parsed, each entry is checked in turn to see if it
- * matches the instruction to be decoded using the test:
- *
- * (insn & mask) == value
- *
- * If no match is found before the end of the table is reached then decoding
- * fails with INSN_REJECTED.
- *
- * When a match is found, decode_regs() is called to validate and modify each
- * of the registers encoded in the instruction; the data it uses to do this
- * is (type_regs >> DECODE_TYPE_BITS). A validation failure will cause decoding
- * to fail with INSN_REJECTED.
- *
- * Once the instruction has passed the above tests, further processing
- * depends on the type of the table entry's decode struct.
- *
- */
-int __kprobes
-kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi,
- const union decode_item *table, bool thumb)
-{
- const struct decode_header *h = (struct decode_header *)table;
- const struct decode_header *next;
- bool matched = false;
-
- insn = prepare_emulated_insn(insn, asi, thumb);
-
- for (;; h = next) {
- enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK;
- u32 regs = h->type_regs.bits >> DECODE_TYPE_BITS;
-
- if (type == DECODE_TYPE_END)
- return INSN_REJECTED;
-
- next = (struct decode_header *)
- ((uintptr_t)h + decode_struct_sizes[type]);
-
- if (!matched && (insn & h->mask.bits) != h->value.bits)
- continue;
-
- if (!decode_regs(&insn, regs))
- return INSN_REJECTED;
-
- switch (type) {
-
- case DECODE_TYPE_TABLE: {
- struct decode_table *d = (struct decode_table *)h;
- next = (struct decode_header *)d->table.table;
- break;
- }
-
- case DECODE_TYPE_CUSTOM: {
- struct decode_custom *d = (struct decode_custom *)h;
- return (*d->decoder.decoder)(insn, asi);
- }
-
- case DECODE_TYPE_SIMULATE: {
- struct decode_simulate *d = (struct decode_simulate *)h;
- asi->insn_handler = d->handler.handler;
- return INSN_GOOD_NO_SLOT;
- }
-
- case DECODE_TYPE_EMULATE: {
- struct decode_emulate *d = (struct decode_emulate *)h;
- asi->insn_handler = d->handler.handler;
- set_emulated_insn(insn, asi, thumb);
- return INSN_GOOD;
- }
-
- case DECODE_TYPE_OR:
- matched = true;
- break;
-
- case DECODE_TYPE_REJECT:
- default:
- return INSN_REJECTED;
- }
- }
- }
void __init arm_kprobe_decode_init(void);
-extern kprobe_check_cc * const kprobe_condition_checks[16];
-
-
-#if __LINUX_ARM_ARCH__ >= 7
-
-/* str_pc_offset is architecturally defined from ARMv7 onwards */
-#define str_pc_offset 8
-#define find_str_pc_offset()
-
-#else /* __LINUX_ARM_ARCH__ < 7 */
-
-/* We need a run-time check to determine str_pc_offset */
-extern int str_pc_offset;
-void __init find_str_pc_offset(void);
-
-#endif
-
-
-/*
- * Update ITSTATE after normal execution of an IT block instruction.
- *
- * The 8 IT state bits are split into two parts in CPSR:
- * ITSTATE<1:0> are in CPSR<26:25>
- * ITSTATE<7:2> are in CPSR<15:10>
- */
-static inline unsigned long it_advance(unsigned long cpsr)
- {
- if ((cpsr & 0x06000400) == 0) {
- /* ITSTATE<2:0> == 0 means end of IT block, so clear IT state */
- cpsr &= ~PSR_IT_MASK;
- } else {
- /* We need to shift left ITSTATE<4:0> */
- const unsigned long mask = 0x06001c00; /* Mask ITSTATE<4:0> */
- unsigned long it = cpsr & mask;
- it <<= 1;
- it |= it >> (27 - 10); /* Carry ITSTATE<2> to correct place */
- it &= mask;
- cpsr &= ~mask;
- cpsr |= it;
- }
- return cpsr;
-}
-
-static inline void __kprobes bx_write_pc(long pcv, struct pt_regs *regs)
-{
- long cpsr = regs->ARM_cpsr;
- if (pcv & 0x1) {
- cpsr |= PSR_T_BIT;
- pcv &= ~0x1;
- } else {
- cpsr &= ~PSR_T_BIT;
- pcv &= ~0x2; /* Avoid UNPREDICTABLE address allignment */
- }
- regs->ARM_cpsr = cpsr;
- regs->ARM_pc = pcv;
-}
-
-
-#if __LINUX_ARM_ARCH__ >= 6
-
-/* Kernels built for >= ARMv6 should never run on <= ARMv5 hardware, so... */
-#define load_write_pc_interworks true
-#define test_load_write_pc_interworking()
-
-#else /* __LINUX_ARM_ARCH__ < 6 */
-
-/* We need run-time testing to determine if load_write_pc() should interwork. */
-extern bool load_write_pc_interworks;
-void __init test_load_write_pc_interworking(void);
-
-#endif
-
-static inline void __kprobes load_write_pc(long pcv, struct pt_regs *regs)
-{
- if (load_write_pc_interworks)
- bx_write_pc(pcv, regs);
- else
- regs->ARM_pc = pcv;
-}
-
-
-#if __LINUX_ARM_ARCH__ >= 7
-
-#define alu_write_pc_interworks true
-#define test_alu_write_pc_interworking()
-
-#elif __LINUX_ARM_ARCH__ <= 5
-
-/* Kernels built for <= ARMv5 should never run on >= ARMv6 hardware, so... */
-#define alu_write_pc_interworks false
-#define test_alu_write_pc_interworking()
-
-#else /* __LINUX_ARM_ARCH__ == 6 */
-
-/* We could be an ARMv6 binary on ARMv7 hardware so we need a run-time check. */
-extern bool alu_write_pc_interworks;
-void __init test_alu_write_pc_interworking(void);
-
-#endif /* __LINUX_ARM_ARCH__ == 6 */
-
-static inline void __kprobes alu_write_pc(long pcv, struct pt_regs *regs)
-{
- if (alu_write_pc_interworks)
- bx_write_pc(pcv, regs);
- else
- regs->ARM_pc = pcv;
-}
-
-
-void __kprobes kprobe_simulate_nop(struct kprobe *p, struct pt_regs *regs);
-void __kprobes kprobe_emulate_none(struct kprobe *p, struct pt_regs *regs);
-
-enum kprobe_insn __kprobes
-kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi);
-
-/*
- * Test if load/store instructions writeback the address register.
- * if P (bit 24) == 0 or W (bit 21) == 1
- */
-#define is_writeback(insn) ((insn ^ 0x01000000) & 0x01200000)
-
-/*
- * The following definitions and macros are used to build instruction
- * decoding tables for use by kprobe_decode_insn.
- *
- * These tables are a concatenation of entries each of which consist of one of
- * the decode_* structs. All of the fields in every type of decode structure
- * are of the union type decode_item, therefore the entire decode table can be
- * viewed as an array of these and declared like:
- *
- * static const union decode_item table_name[] = {};
- *
- * In order to construct each entry in the table, macros are used to
- * initialise a number of sequential decode_item values in a layout which
- * matches the relevant struct. E.g. DECODE_SIMULATE initialise a struct
- * decode_simulate by initialising four decode_item objects like this...
- *
- * {.bits = _type},
- * {.bits = _mask},
- * {.bits = _value},
- * {.handler = _handler},
- *
- * Initialising a specified member of the union means that the compiler
- * will produce a warning if the argument is of an incorrect type.
- *
- * Below is a list of each of the macros used to initialise entries and a
- * description of the action performed when that entry is matched to an
- * instruction. A match is found when (instruction & mask) == value.
- *
- * DECODE_TABLE(mask, value, table)
- * Instruction decoding jumps to parsing the new sub-table 'table'.
- *
- * DECODE_CUSTOM(mask, value, decoder)
- * The custom function 'decoder' is called to the complete decoding
- * of an instruction.
- *
- * DECODE_SIMULATE(mask, value, handler)
- * Set the probes instruction handler to 'handler', this will be used
- * to simulate the instruction when the probe is hit. Decoding returns
- * with INSN_GOOD_NO_SLOT.
- *
- * DECODE_EMULATE(mask, value, handler)
- * Set the probes instruction handler to 'handler', this will be used
- * to emulate the instruction when the probe is hit. The modified
- * instruction (see below) is placed in the probes instruction slot so it
- * may be called by the emulation code. Decoding returns with INSN_GOOD.
- *
- * DECODE_REJECT(mask, value)
- * Instruction decoding fails with INSN_REJECTED
- *
- * DECODE_OR(mask, value)
- * This allows the mask/value test of multiple table entries to be
- * logically ORed. Once an 'or' entry is matched the decoding action to
- * be performed is that of the next entry which isn't an 'or'. E.g.
- *
- * DECODE_OR (mask1, value1)
- * DECODE_OR (mask2, value2)
- * DECODE_SIMULATE (mask3, value3, simulation_handler)
- *
- * This means that if any of the three mask/value pairs match the
- * instruction being decoded, then 'simulation_handler' will be used
- * for it.
- *
- * Both the SIMULATE and EMULATE macros have a second form which take an
- * additional 'regs' argument.
- *
- * DECODE_SIMULATEX(mask, value, handler, regs)
- * DECODE_EMULATEX (mask, value, handler, regs)
- *
- * These are used to specify what kind of CPU register is encoded in each of the
- * least significant 5 nibbles of the instruction being decoded. The regs value
- * is specified using the REGS macro, this takes any of the REG_TYPE_* values
- * from enum decode_reg_type as arguments; only the '*' part of the name is
- * given. E.g.
- *
- * REGS(0, ANY, NOPC, 0, ANY)
- *
- * This indicates an instruction is encoded like:
- *
- * bits 19..16 ignore
- * bits 15..12 any register allowed here
- * bits 11.. 8 any register except PC allowed here
- * bits 7.. 4 ignore
- * bits 3.. 0 any register allowed here
- *
- * This register specification is checked after a decode table entry is found to
- * match an instruction (through the mask/value test). Any invalid register then
- * found in the instruction will cause decoding to fail with INSN_REJECTED. In
- * the above example this would happen if bits 11..8 of the instruction were
- * 1111, indicating R15 or PC.
- *
- * As well as checking for legal combinations of registers, this data is also
- * used to modify the registers encoded in the instructions so that an
- * emulation routines can use it. (See decode_regs() and INSN_NEW_BITS.)
- *
- * Here is a real example which matches ARM instructions of the form
- * "AND <Rd>,<Rn>,<Rm>,<shift> <Rs>"
- *
- * DECODE_EMULATEX (0x0e000090, 0x00000010, emulate_rd12rn16rm0rs8_rwflags,
- * REGS(ANY, ANY, NOPC, 0, ANY)),
- * ^ ^ ^ ^
- * Rn Rd Rs Rm
- *
- * Decoding the instruction "AND R4, R5, R6, ASL R15" will be rejected because
- * Rs == R15
- *
- * Decoding the instruction "AND R4, R5, R6, ASL R7" will be accepted and the
- * instruction will be modified to "AND R0, R2, R3, ASL R1" and then placed into
- * the kprobes instruction slot. This can then be called later by the handler
- * function emulate_rd12rn16rm0rs8_rwflags in order to simulate the instruction.
- */
-
-enum decode_type {
- DECODE_TYPE_END,
- DECODE_TYPE_TABLE,
- DECODE_TYPE_CUSTOM,
- DECODE_TYPE_SIMULATE,
- DECODE_TYPE_EMULATE,
- DECODE_TYPE_OR,
- DECODE_TYPE_REJECT,
- NUM_DECODE_TYPES /* Must be last enum */
-};
-
-#define DECODE_TYPE_BITS 4
-#define DECODE_TYPE_MASK ((1 << DECODE_TYPE_BITS) - 1)
-
-enum decode_reg_type {
- REG_TYPE_NONE = 0, /* Not a register, ignore */
- REG_TYPE_ANY, /* Any register allowed */
- REG_TYPE_SAMEAS16, /* Register should be same as that at bits 19..16 */
- REG_TYPE_SP, /* Register must be SP */
- REG_TYPE_PC, /* Register must be PC */
- REG_TYPE_NOSP, /* Register must not be SP */
- REG_TYPE_NOSPPC, /* Register must not be SP or PC */
- REG_TYPE_NOPC, /* Register must not be PC */
- REG_TYPE_NOPCWB, /* No PC if load/store write-back flag also set */
-
- /* The following types are used when the encoding for PC indicates
- * another instruction form. This distiction only matters for test
- * case coverage checks.
- */
- REG_TYPE_NOPCX, /* Register must not be PC */
- REG_TYPE_NOSPPCX, /* Register must not be SP or PC */
-
- /* Alias to allow '0' arg to be used in REGS macro. */
- REG_TYPE_0 = REG_TYPE_NONE
-};
-
-#define REGS(r16, r12, r8, r4, r0) \
- ((REG_TYPE_##r16) << 16) + \
- ((REG_TYPE_##r12) << 12) + \
- ((REG_TYPE_##r8) << 8) + \
- ((REG_TYPE_##r4) << 4) + \
- (REG_TYPE_##r0)
-
-union decode_item {
- u32 bits;
- const union decode_item *table;
- kprobe_insn_handler_t *handler;
- kprobe_decode_insn_t *decoder;
-};
-
-
-#define DECODE_END \
- {.bits = DECODE_TYPE_END}
-
-
-struct decode_header {
- union decode_item type_regs;
- union decode_item mask;
- union decode_item value;
-};
-
-#define DECODE_HEADER(_type, _mask, _value, _regs) \
- {.bits = (_type) | ((_regs) << DECODE_TYPE_BITS)}, \
- {.bits = (_mask)}, \
- {.bits = (_value)}
-
-
-struct decode_table {
- struct decode_header header;
- union decode_item table;
-};
-
-#define DECODE_TABLE(_mask, _value, _table) \
- DECODE_HEADER(DECODE_TYPE_TABLE, _mask, _value, 0), \
- {.table = (_table)}
-
-
-struct decode_custom {
- struct decode_header header;
- union decode_item decoder;
-};
-
-#define DECODE_CUSTOM(_mask, _value, _decoder) \
- DECODE_HEADER(DECODE_TYPE_CUSTOM, _mask, _value, 0), \
- {.decoder = (_decoder)}
-
-
-struct decode_simulate {
- struct decode_header header;
- union decode_item handler;
-};
-
-#define DECODE_SIMULATEX(_mask, _value, _handler, _regs) \
- DECODE_HEADER(DECODE_TYPE_SIMULATE, _mask, _value, _regs), \
- {.handler = (_handler)}
-
-#define DECODE_SIMULATE(_mask, _value, _handler) \
- DECODE_SIMULATEX(_mask, _value, _handler, 0)
-
-
-struct decode_emulate {
- struct decode_header header;
- union decode_item handler;
-};
-
-#define DECODE_EMULATEX(_mask, _value, _handler, _regs) \
- DECODE_HEADER(DECODE_TYPE_EMULATE, _mask, _value, _regs), \
- {.handler = (_handler)}
-
-#define DECODE_EMULATE(_mask, _value, _handler) \
- DECODE_EMULATEX(_mask, _value, _handler, 0)
-
-
-struct decode_or {
- struct decode_header header;
-};
-
-#define DECODE_OR(_mask, _value) \
- DECODE_HEADER(DECODE_TYPE_OR, _mask, _value, 0)
-
-
-struct decode_reject {
- struct decode_header header;
-};
-
-#define DECODE_REJECT(_mask, _value) \
- DECODE_HEADER(DECODE_TYPE_REJECT, _mask, _value, 0)
-
-
-#ifdef CONFIG_THUMB2_KERNEL
-extern const union decode_item kprobe_decode_thumb16_table[];
-extern const union decode_item kprobe_decode_thumb32_table[];
-#else
-extern const union decode_item kprobe_decode_arm_table[];
-#endif
-
-
-int kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi,
- const union decode_item *table, bool thumb16);
-
+#include "probes.h"
#endif /* _ARM_KERNEL_KPROBES_H */
--- /dev/null
+/*
+ * arch/arm/kernel/probes-arm.c
+ *
+ * Some code moved here from arch/arm/kernel/kprobes-arm.c
+ *
+ * Copyright (C) 2006, 2007 Motorola Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/stddef.h>
+#include <linux/ptrace.h>
+#include <linux/kprobes.h>
+
+#include "kprobes.h"
+#include "probes-arm.h"
+
+#define sign_extend(x, signbit) ((x) | (0 - ((x) & (1 << (signbit)))))
+
+#define branch_displacement(insn) sign_extend(((insn) & 0xffffff) << 2, 25)
+
+/*
+ * To avoid the complications of mimicing single-stepping on a
+ * processor without a Next-PC or a single-step mode, and to
+ * avoid having to deal with the side-effects of boosting, we
+ * simulate or emulate (almost) all ARM instructions.
+ *
+ * "Simulation" is where the instruction's behavior is duplicated in
+ * C code. "Emulation" is where the original instruction is rewritten
+ * and executed, often by altering its registers.
+ *
+ * By having all behavior of the kprobe'd instruction completed before
+ * returning from the kprobe_handler(), all locks (scheduler and
+ * interrupt) can safely be released. There is no need for secondary
+ * breakpoints, no race with MP or preemptable kernels, nor having to
+ * clean up resources counts at a later time impacting overall system
+ * performance. By rewriting the instruction, only the minimum registers
+ * need to be loaded and saved back optimizing performance.
+ *
+ * Calling the insnslot_*_rwflags version of a function doesn't hurt
+ * anything even when the CPSR flags aren't updated by the
+ * instruction. It's just a little slower in return for saving
+ * a little space by not having a duplicate function that doesn't
+ * update the flags. (The same optimization can be said for
+ * instructions that do or don't perform register writeback)
+ * Also, instructions can either read the flags, only write the
+ * flags, or read and write the flags. To save combinations
+ * rather than for sheer performance, flag functions just assume
+ * read and write of flags.
+ */
+
+void __kprobes simulate_bbl(struct kprobe *p, struct pt_regs *regs)
+{
+ kprobe_opcode_t insn = p->opcode;
+ long iaddr = (long)p->addr;
+ int disp = branch_displacement(insn);
+
+ if (insn & (1 << 24))
+ regs->ARM_lr = iaddr + 4;
+
+ regs->ARM_pc = iaddr + 8 + disp;
+}
+
+void __kprobes simulate_blx1(struct kprobe *p, struct pt_regs *regs)
+{
+ kprobe_opcode_t insn = p->opcode;
+ long iaddr = (long)p->addr;
+ int disp = branch_displacement(insn);
+
+ regs->ARM_lr = iaddr + 4;
+ regs->ARM_pc = iaddr + 8 + disp + ((insn >> 23) & 0x2);
+ regs->ARM_cpsr |= PSR_T_BIT;
+}
+
+void __kprobes simulate_blx2bx(struct kprobe *p, struct pt_regs *regs)
+{
+ kprobe_opcode_t insn = p->opcode;
+ int rm = insn & 0xf;
+ long rmv = regs->uregs[rm];
+
+ if (insn & (1 << 5))
+ regs->ARM_lr = (long)p->addr + 4;
+
+ regs->ARM_pc = rmv & ~0x1;
+ regs->ARM_cpsr &= ~PSR_T_BIT;
+ if (rmv & 0x1)
+ regs->ARM_cpsr |= PSR_T_BIT;
+}
+
+void __kprobes simulate_mrs(struct kprobe *p, struct pt_regs *regs)
+{
+ kprobe_opcode_t insn = p->opcode;
+ int rd = (insn >> 12) & 0xf;
+ unsigned long mask = 0xf8ff03df; /* Mask out execution state */
+ regs->uregs[rd] = regs->ARM_cpsr & mask;
+}
+
+void __kprobes simulate_mov_ipsp(struct kprobe *p, struct pt_regs *regs)
+{
+ regs->uregs[12] = regs->uregs[13];
+}
+
+/*
+ * For the instruction masking and comparisons in all the "space_*"
+ * functions below, Do _not_ rearrange the order of tests unless
+ * you're very, very sure of what you are doing. For the sake of
+ * efficiency, the masks for some tests sometimes assume other test
+ * have been done prior to them so the number of patterns to test
+ * for an instruction set can be as broad as possible to reduce the
+ * number of tests needed.
+ */
+
+static const union decode_item arm_1111_table[] = {
+ /* Unconditional instructions */
+
+ /* memory hint 1111 0100 x001 xxxx xxxx xxxx xxxx xxxx */
+ /* PLDI (immediate) 1111 0100 x101 xxxx xxxx xxxx xxxx xxxx */
+ /* PLDW (immediate) 1111 0101 x001 xxxx xxxx xxxx xxxx xxxx */
+ /* PLD (immediate) 1111 0101 x101 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_SIMULATE (0xfe300000, 0xf4100000, kprobe_simulate_nop),
+
+ /* memory hint 1111 0110 x001 xxxx xxxx xxxx xxx0 xxxx */
+ /* PLDI (register) 1111 0110 x101 xxxx xxxx xxxx xxx0 xxxx */
+ /* PLDW (register) 1111 0111 x001 xxxx xxxx xxxx xxx0 xxxx */
+ /* PLD (register) 1111 0111 x101 xxxx xxxx xxxx xxx0 xxxx */
+ DECODE_SIMULATE (0xfe300010, 0xf6100000, kprobe_simulate_nop),
+
+ /* BLX (immediate) 1111 101x xxxx xxxx xxxx xxxx xxxx xxxx */
+ DECODE_SIMULATE (0xfe000000, 0xfa000000, simulate_blx1),
+
+ /* CPS 1111 0001 0000 xxx0 xxxx xxxx xx0x xxxx */
+ /* SETEND 1111 0001 0000 0001 xxxx xxxx 0000 xxxx */
+ /* SRS 1111 100x x1x0 xxxx xxxx xxxx xxxx xxxx */
+ /* RFE 1111 100x x0x1 xxxx xxxx xxxx xxxx xxxx */
+
+ /* Coprocessor instructions... */
+ /* MCRR2 1111 1100 0100 xxxx xxxx xxxx xxxx xxxx */
+ /* MRRC2 1111 1100 0101 xxxx xxxx xxxx xxxx xxxx */
+ /* LDC2 1111 110x xxx1 xxxx xxxx xxxx xxxx xxxx */
+ /* STC2 1111 110x xxx0 xxxx xxxx xxxx xxxx xxxx */
+ /* CDP2 1111 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */
+ /* MCR2 1111 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */
+ /* MRC2 1111 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */
+
+ /* Other unallocated instructions... */
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_0001_0xx0____0xxx_table[] = {
+ /* Miscellaneous instructions */
+
+ /* MRS cpsr cccc 0001 0000 xxxx xxxx xxxx 0000 xxxx */
+ DECODE_SIMULATEX(0x0ff000f0, 0x01000000, simulate_mrs,
+ REGS(0, NOPC, 0, 0, 0)),
+
+ /* BX cccc 0001 0010 xxxx xxxx xxxx 0001 xxxx */
+ DECODE_SIMULATE (0x0ff000f0, 0x01200010, simulate_blx2bx),
+
+ /* BLX (register) cccc 0001 0010 xxxx xxxx xxxx 0011 xxxx */
+ DECODE_SIMULATEX(0x0ff000f0, 0x01200030, simulate_blx2bx,
+ REGS(0, 0, 0, 0, NOPC)),
+
+ /* CLZ cccc 0001 0110 xxxx xxxx xxxx 0001 xxxx */
+ DECODE_EMULATEX (0x0ff000f0, 0x01600010, emulate_rd12rm0_noflags_nopc,
+ REGS(0, NOPC, 0, 0, NOPC)),
+
+ /* QADD cccc 0001 0000 xxxx xxxx xxxx 0101 xxxx */
+ /* QSUB cccc 0001 0010 xxxx xxxx xxxx 0101 xxxx */
+ /* QDADD cccc 0001 0100 xxxx xxxx xxxx 0101 xxxx */
+ /* QDSUB cccc 0001 0110 xxxx xxxx xxxx 0101 xxxx */
+ DECODE_EMULATEX (0x0f9000f0, 0x01000050, emulate_rd12rn16rm0_rwflags_nopc,
+ REGS(NOPC, NOPC, 0, 0, NOPC)),
+
+ /* BXJ cccc 0001 0010 xxxx xxxx xxxx 0010 xxxx */
+ /* MSR cccc 0001 0x10 xxxx xxxx xxxx 0000 xxxx */
+ /* MRS spsr cccc 0001 0100 xxxx xxxx xxxx 0000 xxxx */
+ /* BKPT 1110 0001 0010 xxxx xxxx xxxx 0111 xxxx */
+ /* SMC cccc 0001 0110 xxxx xxxx xxxx 0111 xxxx */
+ /* And unallocated instructions... */
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_0001_0xx0____1xx0_table[] = {
+ /* Halfword multiply and multiply-accumulate */
+
+ /* SMLALxy cccc 0001 0100 xxxx xxxx xxxx 1xx0 xxxx */
+ DECODE_EMULATEX (0x0ff00090, 0x01400080, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
+ REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+ /* SMULWy cccc 0001 0010 xxxx xxxx xxxx 1x10 xxxx */
+ DECODE_OR (0x0ff000b0, 0x012000a0),
+ /* SMULxy cccc 0001 0110 xxxx xxxx xxxx 1xx0 xxxx */
+ DECODE_EMULATEX (0x0ff00090, 0x01600080, emulate_rd16rn12rm0rs8_rwflags_nopc,
+ REGS(NOPC, 0, NOPC, 0, NOPC)),
+
+ /* SMLAxy cccc 0001 0000 xxxx xxxx xxxx 1xx0 xxxx */
+ DECODE_OR (0x0ff00090, 0x01000080),
+ /* SMLAWy cccc 0001 0010 xxxx xxxx xxxx 1x00 xxxx */
+ DECODE_EMULATEX (0x0ff000b0, 0x01200080, emulate_rd16rn12rm0rs8_rwflags_nopc,
+ REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_0000_____1001_table[] = {
+ /* Multiply and multiply-accumulate */
+
+ /* MUL cccc 0000 0000 xxxx xxxx xxxx 1001 xxxx */
+ /* MULS cccc 0000 0001 xxxx xxxx xxxx 1001 xxxx */
+ DECODE_EMULATEX (0x0fe000f0, 0x00000090, emulate_rd16rn12rm0rs8_rwflags_nopc,
+ REGS(NOPC, 0, NOPC, 0, NOPC)),
+
+ /* MLA cccc 0000 0010 xxxx xxxx xxxx 1001 xxxx */
+ /* MLAS cccc 0000 0011 xxxx xxxx xxxx 1001 xxxx */
+ DECODE_OR (0x0fe000f0, 0x00200090),
+ /* MLS cccc 0000 0110 xxxx xxxx xxxx 1001 xxxx */
+ DECODE_EMULATEX (0x0ff000f0, 0x00600090, emulate_rd16rn12rm0rs8_rwflags_nopc,
+ REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+ /* UMAAL cccc 0000 0100 xxxx xxxx xxxx 1001 xxxx */
+ DECODE_OR (0x0ff000f0, 0x00400090),
+ /* UMULL cccc 0000 1000 xxxx xxxx xxxx 1001 xxxx */
+ /* UMULLS cccc 0000 1001 xxxx xxxx xxxx 1001 xxxx */
+ /* UMLAL cccc 0000 1010 xxxx xxxx xxxx 1001 xxxx */
+ /* UMLALS cccc 0000 1011 xxxx xxxx xxxx 1001 xxxx */
+ /* SMULL cccc 0000 1100 xxxx xxxx xxxx 1001 xxxx */
+ /* SMULLS cccc 0000 1101 xxxx xxxx xxxx 1001 xxxx */
+ /* SMLAL cccc 0000 1110 xxxx xxxx xxxx 1001 xxxx */
+ /* SMLALS cccc 0000 1111 xxxx xxxx xxxx 1001 xxxx */
+ DECODE_EMULATEX (0x0f8000f0, 0x00800090, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
+ REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_0001_____1001_table[] = {
+ /* Synchronization primitives */
+
+#if __LINUX_ARM_ARCH__ < 6
+ /* Deprecated on ARMv6 and may be UNDEFINED on v7 */
+ /* SMP/SWPB cccc 0001 0x00 xxxx xxxx xxxx 1001 xxxx */
+ DECODE_EMULATEX (0x0fb000f0, 0x01000090, emulate_rd12rn16rm0_rwflags_nopc,
+ REGS(NOPC, NOPC, 0, 0, NOPC)),
+#endif
+ /* LDREX/STREX{,D,B,H} cccc 0001 1xxx xxxx xxxx xxxx 1001 xxxx */
+ /* And unallocated instructions... */
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_000x_____1xx1_table[] = {
+ /* Extra load/store instructions */
+
+ /* STRHT cccc 0000 xx10 xxxx xxxx xxxx 1011 xxxx */
+ /* ??? cccc 0000 xx10 xxxx xxxx xxxx 11x1 xxxx */
+ /* LDRHT cccc 0000 xx11 xxxx xxxx xxxx 1011 xxxx */
+ /* LDRSBT cccc 0000 xx11 xxxx xxxx xxxx 1101 xxxx */
+ /* LDRSHT cccc 0000 xx11 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_REJECT (0x0f200090, 0x00200090),
+
+ /* LDRD/STRD lr,pc,{... cccc 000x x0x0 xxxx 111x xxxx 1101 xxxx */
+ DECODE_REJECT (0x0e10e0d0, 0x0000e0d0),
+
+ /* LDRD (register) cccc 000x x0x0 xxxx xxxx xxxx 1101 xxxx */
+ /* STRD (register) cccc 000x x0x0 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_EMULATEX (0x0e5000d0, 0x000000d0, emulate_ldrdstrd,
+ REGS(NOPCWB, NOPCX, 0, 0, NOPC)),
+
+ /* LDRD (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1101 xxxx */
+ /* STRD (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_EMULATEX (0x0e5000d0, 0x004000d0, emulate_ldrdstrd,
+ REGS(NOPCWB, NOPCX, 0, 0, 0)),
+
+ /* STRH (register) cccc 000x x0x0 xxxx xxxx xxxx 1011 xxxx */
+ DECODE_EMULATEX (0x0e5000f0, 0x000000b0, emulate_str,
+ REGS(NOPCWB, NOPC, 0, 0, NOPC)),
+
+ /* LDRH (register) cccc 000x x0x1 xxxx xxxx xxxx 1011 xxxx */
+ /* LDRSB (register) cccc 000x x0x1 xxxx xxxx xxxx 1101 xxxx */
+ /* LDRSH (register) cccc 000x x0x1 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_EMULATEX (0x0e500090, 0x00100090, emulate_ldr,
+ REGS(NOPCWB, NOPC, 0, 0, NOPC)),
+
+ /* STRH (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1011 xxxx */
+ DECODE_EMULATEX (0x0e5000f0, 0x004000b0, emulate_str,
+ REGS(NOPCWB, NOPC, 0, 0, 0)),
+
+ /* LDRH (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1011 xxxx */
+ /* LDRSB (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1101 xxxx */
+ /* LDRSH (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_EMULATEX (0x0e500090, 0x00500090, emulate_ldr,
+ REGS(NOPCWB, NOPC, 0, 0, 0)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_000x_table[] = {
+ /* Data-processing (register) */
+
+ /* <op>S PC, ... cccc 000x xxx1 xxxx 1111 xxxx xxxx xxxx */
+ DECODE_REJECT (0x0e10f000, 0x0010f000),
+
+ /* MOV IP, SP 1110 0001 1010 0000 1100 0000 0000 1101 */
+ DECODE_SIMULATE (0xffffffff, 0xe1a0c00d, simulate_mov_ipsp),
+
+ /* TST (register) cccc 0001 0001 xxxx xxxx xxxx xxx0 xxxx */
+ /* TEQ (register) cccc 0001 0011 xxxx xxxx xxxx xxx0 xxxx */
+ /* CMP (register) cccc 0001 0101 xxxx xxxx xxxx xxx0 xxxx */
+ /* CMN (register) cccc 0001 0111 xxxx xxxx xxxx xxx0 xxxx */
+ DECODE_EMULATEX (0x0f900010, 0x01100000, emulate_rd12rn16rm0rs8_rwflags,
+ REGS(ANY, 0, 0, 0, ANY)),
+
+ /* MOV (register) cccc 0001 101x xxxx xxxx xxxx xxx0 xxxx */
+ /* MVN (register) cccc 0001 111x xxxx xxxx xxxx xxx0 xxxx */
+ DECODE_EMULATEX (0x0fa00010, 0x01a00000, emulate_rd12rn16rm0rs8_rwflags,
+ REGS(0, ANY, 0, 0, ANY)),
+
+ /* AND (register) cccc 0000 000x xxxx xxxx xxxx xxx0 xxxx */
+ /* EOR (register) cccc 0000 001x xxxx xxxx xxxx xxx0 xxxx */
+ /* SUB (register) cccc 0000 010x xxxx xxxx xxxx xxx0 xxxx */
+ /* RSB (register) cccc 0000 011x xxxx xxxx xxxx xxx0 xxxx */
+ /* ADD (register) cccc 0000 100x xxxx xxxx xxxx xxx0 xxxx */
+ /* ADC (register) cccc 0000 101x xxxx xxxx xxxx xxx0 xxxx */
+ /* SBC (register) cccc 0000 110x xxxx xxxx xxxx xxx0 xxxx */
+ /* RSC (register) cccc 0000 111x xxxx xxxx xxxx xxx0 xxxx */
+ /* ORR (register) cccc 0001 100x xxxx xxxx xxxx xxx0 xxxx */
+ /* BIC (register) cccc 0001 110x xxxx xxxx xxxx xxx0 xxxx */
+ DECODE_EMULATEX (0x0e000010, 0x00000000, emulate_rd12rn16rm0rs8_rwflags,
+ REGS(ANY, ANY, 0, 0, ANY)),
+
+ /* TST (reg-shift reg) cccc 0001 0001 xxxx xxxx xxxx 0xx1 xxxx */
+ /* TEQ (reg-shift reg) cccc 0001 0011 xxxx xxxx xxxx 0xx1 xxxx */
+ /* CMP (reg-shift reg) cccc 0001 0101 xxxx xxxx xxxx 0xx1 xxxx */
+ /* CMN (reg-shift reg) cccc 0001 0111 xxxx xxxx xxxx 0xx1 xxxx */
+ DECODE_EMULATEX (0x0f900090, 0x01100010, emulate_rd12rn16rm0rs8_rwflags,
+ REGS(ANY, 0, NOPC, 0, ANY)),
+
+ /* MOV (reg-shift reg) cccc 0001 101x xxxx xxxx xxxx 0xx1 xxxx */
+ /* MVN (reg-shift reg) cccc 0001 111x xxxx xxxx xxxx 0xx1 xxxx */
+ DECODE_EMULATEX (0x0fa00090, 0x01a00010, emulate_rd12rn16rm0rs8_rwflags,
+ REGS(0, ANY, NOPC, 0, ANY)),
+
+ /* AND (reg-shift reg) cccc 0000 000x xxxx xxxx xxxx 0xx1 xxxx */
+ /* EOR (reg-shift reg) cccc 0000 001x xxxx xxxx xxxx 0xx1 xxxx */
+ /* SUB (reg-shift reg) cccc 0000 010x xxxx xxxx xxxx 0xx1 xxxx */
+ /* RSB (reg-shift reg) cccc 0000 011x xxxx xxxx xxxx 0xx1 xxxx */
+ /* ADD (reg-shift reg) cccc 0000 100x xxxx xxxx xxxx 0xx1 xxxx */
+ /* ADC (reg-shift reg) cccc 0000 101x xxxx xxxx xxxx 0xx1 xxxx */
+ /* SBC (reg-shift reg) cccc 0000 110x xxxx xxxx xxxx 0xx1 xxxx */
+ /* RSC (reg-shift reg) cccc 0000 111x xxxx xxxx xxxx 0xx1 xxxx */
+ /* ORR (reg-shift reg) cccc 0001 100x xxxx xxxx xxxx 0xx1 xxxx */
+ /* BIC (reg-shift reg) cccc 0001 110x xxxx xxxx xxxx 0xx1 xxxx */
+ DECODE_EMULATEX (0x0e000090, 0x00000010, emulate_rd12rn16rm0rs8_rwflags,
+ REGS(ANY, ANY, NOPC, 0, ANY)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_001x_table[] = {
+ /* Data-processing (immediate) */
+
+ /* MOVW cccc 0011 0000 xxxx xxxx xxxx xxxx xxxx */
+ /* MOVT cccc 0011 0100 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0fb00000, 0x03000000, emulate_rd12rm0_noflags_nopc,
+ REGS(0, NOPC, 0, 0, 0)),
+
+ /* YIELD cccc 0011 0010 0000 xxxx xxxx 0000 0001 */
+ DECODE_OR (0x0fff00ff, 0x03200001),
+ /* SEV cccc 0011 0010 0000 xxxx xxxx 0000 0100 */
+ DECODE_EMULATE (0x0fff00ff, 0x03200004, kprobe_emulate_none),
+ /* NOP cccc 0011 0010 0000 xxxx xxxx 0000 0000 */
+ /* WFE cccc 0011 0010 0000 xxxx xxxx 0000 0010 */
+ /* WFI cccc 0011 0010 0000 xxxx xxxx 0000 0011 */
+ DECODE_SIMULATE (0x0fff00fc, 0x03200000, kprobe_simulate_nop),
+ /* DBG cccc 0011 0010 0000 xxxx xxxx ffff xxxx */
+ /* unallocated hints cccc 0011 0010 0000 xxxx xxxx xxxx xxxx */
+ /* MSR (immediate) cccc 0011 0x10 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_REJECT (0x0fb00000, 0x03200000),
+
+ /* <op>S PC, ... cccc 001x xxx1 xxxx 1111 xxxx xxxx xxxx */
+ DECODE_REJECT (0x0e10f000, 0x0210f000),
+
+ /* TST (immediate) cccc 0011 0001 xxxx xxxx xxxx xxxx xxxx */
+ /* TEQ (immediate) cccc 0011 0011 xxxx xxxx xxxx xxxx xxxx */
+ /* CMP (immediate) cccc 0011 0101 xxxx xxxx xxxx xxxx xxxx */
+ /* CMN (immediate) cccc 0011 0111 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0f900000, 0x03100000, emulate_rd12rn16rm0rs8_rwflags,
+ REGS(ANY, 0, 0, 0, 0)),
+
+ /* MOV (immediate) cccc 0011 101x xxxx xxxx xxxx xxxx xxxx */
+ /* MVN (immediate) cccc 0011 111x xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0fa00000, 0x03a00000, emulate_rd12rn16rm0rs8_rwflags,
+ REGS(0, ANY, 0, 0, 0)),
+
+ /* AND (immediate) cccc 0010 000x xxxx xxxx xxxx xxxx xxxx */
+ /* EOR (immediate) cccc 0010 001x xxxx xxxx xxxx xxxx xxxx */
+ /* SUB (immediate) cccc 0010 010x xxxx xxxx xxxx xxxx xxxx */
+ /* RSB (immediate) cccc 0010 011x xxxx xxxx xxxx xxxx xxxx */
+ /* ADD (immediate) cccc 0010 100x xxxx xxxx xxxx xxxx xxxx */
+ /* ADC (immediate) cccc 0010 101x xxxx xxxx xxxx xxxx xxxx */
+ /* SBC (immediate) cccc 0010 110x xxxx xxxx xxxx xxxx xxxx */
+ /* RSC (immediate) cccc 0010 111x xxxx xxxx xxxx xxxx xxxx */
+ /* ORR (immediate) cccc 0011 100x xxxx xxxx xxxx xxxx xxxx */
+ /* BIC (immediate) cccc 0011 110x xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0e000000, 0x02000000, emulate_rd12rn16rm0rs8_rwflags,
+ REGS(ANY, ANY, 0, 0, 0)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_0110_____xxx1_table[] = {
+ /* Media instructions */
+
+ /* SEL cccc 0110 1000 xxxx xxxx xxxx 1011 xxxx */
+ DECODE_EMULATEX (0x0ff000f0, 0x068000b0, emulate_rd12rn16rm0_rwflags_nopc,
+ REGS(NOPC, NOPC, 0, 0, NOPC)),
+
+ /* SSAT cccc 0110 101x xxxx xxxx xxxx xx01 xxxx */
+ /* USAT cccc 0110 111x xxxx xxxx xxxx xx01 xxxx */
+ DECODE_OR(0x0fa00030, 0x06a00010),
+ /* SSAT16 cccc 0110 1010 xxxx xxxx xxxx 0011 xxxx */
+ /* USAT16 cccc 0110 1110 xxxx xxxx xxxx 0011 xxxx */
+ DECODE_EMULATEX (0x0fb000f0, 0x06a00030, emulate_rd12rn16rm0_rwflags_nopc,
+ REGS(0, NOPC, 0, 0, NOPC)),
+
+ /* REV cccc 0110 1011 xxxx xxxx xxxx 0011 xxxx */
+ /* REV16 cccc 0110 1011 xxxx xxxx xxxx 1011 xxxx */
+ /* RBIT cccc 0110 1111 xxxx xxxx xxxx 0011 xxxx */
+ /* REVSH cccc 0110 1111 xxxx xxxx xxxx 1011 xxxx */
+ DECODE_EMULATEX (0x0fb00070, 0x06b00030, emulate_rd12rm0_noflags_nopc,
+ REGS(0, NOPC, 0, 0, NOPC)),
+
+ /* ??? cccc 0110 0x00 xxxx xxxx xxxx xxx1 xxxx */
+ DECODE_REJECT (0x0fb00010, 0x06000010),
+ /* ??? cccc 0110 0xxx xxxx xxxx xxxx 1011 xxxx */
+ DECODE_REJECT (0x0f8000f0, 0x060000b0),
+ /* ??? cccc 0110 0xxx xxxx xxxx xxxx 1101 xxxx */
+ DECODE_REJECT (0x0f8000f0, 0x060000d0),
+ /* SADD16 cccc 0110 0001 xxxx xxxx xxxx 0001 xxxx */
+ /* SADDSUBX cccc 0110 0001 xxxx xxxx xxxx 0011 xxxx */
+ /* SSUBADDX cccc 0110 0001 xxxx xxxx xxxx 0101 xxxx */
+ /* SSUB16 cccc 0110 0001 xxxx xxxx xxxx 0111 xxxx */
+ /* SADD8 cccc 0110 0001 xxxx xxxx xxxx 1001 xxxx */
+ /* SSUB8 cccc 0110 0001 xxxx xxxx xxxx 1111 xxxx */
+ /* QADD16 cccc 0110 0010 xxxx xxxx xxxx 0001 xxxx */
+ /* QADDSUBX cccc 0110 0010 xxxx xxxx xxxx 0011 xxxx */
+ /* QSUBADDX cccc 0110 0010 xxxx xxxx xxxx 0101 xxxx */
+ /* QSUB16 cccc 0110 0010 xxxx xxxx xxxx 0111 xxxx */
+ /* QADD8 cccc 0110 0010 xxxx xxxx xxxx 1001 xxxx */
+ /* QSUB8 cccc 0110 0010 xxxx xxxx xxxx 1111 xxxx */
+ /* SHADD16 cccc 0110 0011 xxxx xxxx xxxx 0001 xxxx */
+ /* SHADDSUBX cccc 0110 0011 xxxx xxxx xxxx 0011 xxxx */
+ /* SHSUBADDX cccc 0110 0011 xxxx xxxx xxxx 0101 xxxx */
+ /* SHSUB16 cccc 0110 0011 xxxx xxxx xxxx 0111 xxxx */
+ /* SHADD8 cccc 0110 0011 xxxx xxxx xxxx 1001 xxxx */
+ /* SHSUB8 cccc 0110 0011 xxxx xxxx xxxx 1111 xxxx */
+ /* UADD16 cccc 0110 0101 xxxx xxxx xxxx 0001 xxxx */
+ /* UADDSUBX cccc 0110 0101 xxxx xxxx xxxx 0011 xxxx */
+ /* USUBADDX cccc 0110 0101 xxxx xxxx xxxx 0101 xxxx */
+ /* USUB16 cccc 0110 0101 xxxx xxxx xxxx 0111 xxxx */
+ /* UADD8 cccc 0110 0101 xxxx xxxx xxxx 1001 xxxx */
+ /* USUB8 cccc 0110 0101 xxxx xxxx xxxx 1111 xxxx */
+ /* UQADD16 cccc 0110 0110 xxxx xxxx xxxx 0001 xxxx */
+ /* UQADDSUBX cccc 0110 0110 xxxx xxxx xxxx 0011 xxxx */
+ /* UQSUBADDX cccc 0110 0110 xxxx xxxx xxxx 0101 xxxx */
+ /* UQSUB16 cccc 0110 0110 xxxx xxxx xxxx 0111 xxxx */
+ /* UQADD8 cccc 0110 0110 xxxx xxxx xxxx 1001 xxxx */
+ /* UQSUB8 cccc 0110 0110 xxxx xxxx xxxx 1111 xxxx */
+ /* UHADD16 cccc 0110 0111 xxxx xxxx xxxx 0001 xxxx */
+ /* UHADDSUBX cccc 0110 0111 xxxx xxxx xxxx 0011 xxxx */
+ /* UHSUBADDX cccc 0110 0111 xxxx xxxx xxxx 0101 xxxx */
+ /* UHSUB16 cccc 0110 0111 xxxx xxxx xxxx 0111 xxxx */
+ /* UHADD8 cccc 0110 0111 xxxx xxxx xxxx 1001 xxxx */
+ /* UHSUB8 cccc 0110 0111 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_EMULATEX (0x0f800010, 0x06000010, emulate_rd12rn16rm0_rwflags_nopc,
+ REGS(NOPC, NOPC, 0, 0, NOPC)),
+
+ /* PKHBT cccc 0110 1000 xxxx xxxx xxxx x001 xxxx */
+ /* PKHTB cccc 0110 1000 xxxx xxxx xxxx x101 xxxx */
+ DECODE_EMULATEX (0x0ff00030, 0x06800010, emulate_rd12rn16rm0_rwflags_nopc,
+ REGS(NOPC, NOPC, 0, 0, NOPC)),
+
+ /* ??? cccc 0110 1001 xxxx xxxx xxxx 0111 xxxx */
+ /* ??? cccc 0110 1101 xxxx xxxx xxxx 0111 xxxx */
+ DECODE_REJECT (0x0fb000f0, 0x06900070),
+
+ /* SXTB16 cccc 0110 1000 1111 xxxx xxxx 0111 xxxx */
+ /* SXTB cccc 0110 1010 1111 xxxx xxxx 0111 xxxx */
+ /* SXTH cccc 0110 1011 1111 xxxx xxxx 0111 xxxx */
+ /* UXTB16 cccc 0110 1100 1111 xxxx xxxx 0111 xxxx */
+ /* UXTB cccc 0110 1110 1111 xxxx xxxx 0111 xxxx */
+ /* UXTH cccc 0110 1111 1111 xxxx xxxx 0111 xxxx */
+ DECODE_EMULATEX (0x0f8f00f0, 0x068f0070, emulate_rd12rm0_noflags_nopc,
+ REGS(0, NOPC, 0, 0, NOPC)),
+
+ /* SXTAB16 cccc 0110 1000 xxxx xxxx xxxx 0111 xxxx */
+ /* SXTAB cccc 0110 1010 xxxx xxxx xxxx 0111 xxxx */
+ /* SXTAH cccc 0110 1011 xxxx xxxx xxxx 0111 xxxx */
+ /* UXTAB16 cccc 0110 1100 xxxx xxxx xxxx 0111 xxxx */
+ /* UXTAB cccc 0110 1110 xxxx xxxx xxxx 0111 xxxx */
+ /* UXTAH cccc 0110 1111 xxxx xxxx xxxx 0111 xxxx */
+ DECODE_EMULATEX (0x0f8000f0, 0x06800070, emulate_rd12rn16rm0_rwflags_nopc,
+ REGS(NOPCX, NOPC, 0, 0, NOPC)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_0111_____xxx1_table[] = {
+ /* Media instructions */
+
+ /* UNDEFINED cccc 0111 1111 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_REJECT (0x0ff000f0, 0x07f000f0),
+
+ /* SMLALD cccc 0111 0100 xxxx xxxx xxxx 00x1 xxxx */
+ /* SMLSLD cccc 0111 0100 xxxx xxxx xxxx 01x1 xxxx */
+ DECODE_EMULATEX (0x0ff00090, 0x07400010, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc,
+ REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+ /* SMUAD cccc 0111 0000 xxxx 1111 xxxx 00x1 xxxx */
+ /* SMUSD cccc 0111 0000 xxxx 1111 xxxx 01x1 xxxx */
+ DECODE_OR (0x0ff0f090, 0x0700f010),
+ /* SMMUL cccc 0111 0101 xxxx 1111 xxxx 00x1 xxxx */
+ DECODE_OR (0x0ff0f0d0, 0x0750f010),
+ /* USAD8 cccc 0111 1000 xxxx 1111 xxxx 0001 xxxx */
+ DECODE_EMULATEX (0x0ff0f0f0, 0x0780f010, emulate_rd16rn12rm0rs8_rwflags_nopc,
+ REGS(NOPC, 0, NOPC, 0, NOPC)),
+
+ /* SMLAD cccc 0111 0000 xxxx xxxx xxxx 00x1 xxxx */
+ /* SMLSD cccc 0111 0000 xxxx xxxx xxxx 01x1 xxxx */
+ DECODE_OR (0x0ff00090, 0x07000010),
+ /* SMMLA cccc 0111 0101 xxxx xxxx xxxx 00x1 xxxx */
+ DECODE_OR (0x0ff000d0, 0x07500010),
+ /* USADA8 cccc 0111 1000 xxxx xxxx xxxx 0001 xxxx */
+ DECODE_EMULATEX (0x0ff000f0, 0x07800010, emulate_rd16rn12rm0rs8_rwflags_nopc,
+ REGS(NOPC, NOPCX, NOPC, 0, NOPC)),
+
+ /* SMMLS cccc 0111 0101 xxxx xxxx xxxx 11x1 xxxx */
+ DECODE_EMULATEX (0x0ff000d0, 0x075000d0, emulate_rd16rn12rm0rs8_rwflags_nopc,
+ REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+ /* SBFX cccc 0111 101x xxxx xxxx xxxx x101 xxxx */
+ /* UBFX cccc 0111 111x xxxx xxxx xxxx x101 xxxx */
+ DECODE_EMULATEX (0x0fa00070, 0x07a00050, emulate_rd12rm0_noflags_nopc,
+ REGS(0, NOPC, 0, 0, NOPC)),
+
+ /* BFC cccc 0111 110x xxxx xxxx xxxx x001 1111 */
+ DECODE_EMULATEX (0x0fe0007f, 0x07c0001f, emulate_rd12rm0_noflags_nopc,
+ REGS(0, NOPC, 0, 0, 0)),
+
+ /* BFI cccc 0111 110x xxxx xxxx xxxx x001 xxxx */
+ DECODE_EMULATEX (0x0fe00070, 0x07c00010, emulate_rd12rm0_noflags_nopc,
+ REGS(0, NOPC, 0, 0, NOPCX)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_01xx_table[] = {
+ /* Load/store word and unsigned byte */
+
+ /* LDRB/STRB pc,[...] cccc 01xx x0xx xxxx xxxx xxxx xxxx xxxx */
+ DECODE_REJECT (0x0c40f000, 0x0440f000),
+
+ /* STRT cccc 01x0 x010 xxxx xxxx xxxx xxxx xxxx */
+ /* LDRT cccc 01x0 x011 xxxx xxxx xxxx xxxx xxxx */
+ /* STRBT cccc 01x0 x110 xxxx xxxx xxxx xxxx xxxx */
+ /* LDRBT cccc 01x0 x111 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_REJECT (0x0d200000, 0x04200000),
+
+ /* STR (immediate) cccc 010x x0x0 xxxx xxxx xxxx xxxx xxxx */
+ /* STRB (immediate) cccc 010x x1x0 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0e100000, 0x04000000, emulate_str,
+ REGS(NOPCWB, ANY, 0, 0, 0)),
+
+ /* LDR (immediate) cccc 010x x0x1 xxxx xxxx xxxx xxxx xxxx */
+ /* LDRB (immediate) cccc 010x x1x1 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0e100000, 0x04100000, emulate_ldr,
+ REGS(NOPCWB, ANY, 0, 0, 0)),
+
+ /* STR (register) cccc 011x x0x0 xxxx xxxx xxxx xxxx xxxx */
+ /* STRB (register) cccc 011x x1x0 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0e100000, 0x06000000, emulate_str,
+ REGS(NOPCWB, ANY, 0, 0, NOPC)),
+
+ /* LDR (register) cccc 011x x0x1 xxxx xxxx xxxx xxxx xxxx */
+ /* LDRB (register) cccc 011x x1x1 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0e100000, 0x06100000, emulate_ldr,
+ REGS(NOPCWB, ANY, 0, 0, NOPC)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_100x_table[] = {
+ /* Block data transfer instructions */
+
+ /* LDM cccc 100x x0x1 xxxx xxxx xxxx xxxx xxxx */
+ /* STM cccc 100x x0x0 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_CUSTOM (0x0e400000, 0x08000000, kprobe_decode_ldmstm),
+
+ /* STM (user registers) cccc 100x x1x0 xxxx xxxx xxxx xxxx xxxx */
+ /* LDM (user registers) cccc 100x x1x1 xxxx 0xxx xxxx xxxx xxxx */
+ /* LDM (exception ret) cccc 100x x1x1 xxxx 1xxx xxxx xxxx xxxx */
+ DECODE_END
+};
+
+const union decode_item kprobe_decode_arm_table[] = {
+ /*
+ * Unconditional instructions
+ * 1111 xxxx xxxx xxxx xxxx xxxx xxxx xxxx
+ */
+ DECODE_TABLE (0xf0000000, 0xf0000000, arm_1111_table),
+
+ /*
+ * Miscellaneous instructions
+ * cccc 0001 0xx0 xxxx xxxx xxxx 0xxx xxxx
+ */
+ DECODE_TABLE (0x0f900080, 0x01000000, arm_cccc_0001_0xx0____0xxx_table),
+
+ /*
+ * Halfword multiply and multiply-accumulate
+ * cccc 0001 0xx0 xxxx xxxx xxxx 1xx0 xxxx
+ */
+ DECODE_TABLE (0x0f900090, 0x01000080, arm_cccc_0001_0xx0____1xx0_table),
+
+ /*
+ * Multiply and multiply-accumulate
+ * cccc 0000 xxxx xxxx xxxx xxxx 1001 xxxx
+ */
+ DECODE_TABLE (0x0f0000f0, 0x00000090, arm_cccc_0000_____1001_table),
+
+ /*
+ * Synchronization primitives
+ * cccc 0001 xxxx xxxx xxxx xxxx 1001 xxxx
+ */
+ DECODE_TABLE (0x0f0000f0, 0x01000090, arm_cccc_0001_____1001_table),
+
+ /*
+ * Extra load/store instructions
+ * cccc 000x xxxx xxxx xxxx xxxx 1xx1 xxxx
+ */
+ DECODE_TABLE (0x0e000090, 0x00000090, arm_cccc_000x_____1xx1_table),
+
+ /*
+ * Data-processing (register)
+ * cccc 000x xxxx xxxx xxxx xxxx xxx0 xxxx
+ * Data-processing (register-shifted register)
+ * cccc 000x xxxx xxxx xxxx xxxx 0xx1 xxxx
+ */
+ DECODE_TABLE (0x0e000000, 0x00000000, arm_cccc_000x_table),
+
+ /*
+ * Data-processing (immediate)
+ * cccc 001x xxxx xxxx xxxx xxxx xxxx xxxx
+ */
+ DECODE_TABLE (0x0e000000, 0x02000000, arm_cccc_001x_table),
+
+ /*
+ * Media instructions
+ * cccc 011x xxxx xxxx xxxx xxxx xxx1 xxxx
+ */
+ DECODE_TABLE (0x0f000010, 0x06000010, arm_cccc_0110_____xxx1_table),
+ DECODE_TABLE (0x0f000010, 0x07000010, arm_cccc_0111_____xxx1_table),
+
+ /*
+ * Load/store word and unsigned byte
+ * cccc 01xx xxxx xxxx xxxx xxxx xxxx xxxx
+ */
+ DECODE_TABLE (0x0c000000, 0x04000000, arm_cccc_01xx_table),
+
+ /*
+ * Block data transfer instructions
+ * cccc 100x xxxx xxxx xxxx xxxx xxxx xxxx
+ */
+ DECODE_TABLE (0x0e000000, 0x08000000, arm_cccc_100x_table),
+
+ /* B cccc 1010 xxxx xxxx xxxx xxxx xxxx xxxx */
+ /* BL cccc 1011 xxxx xxxx xxxx xxxx xxxx xxxx */
+ DECODE_SIMULATE (0x0e000000, 0x0a000000, simulate_bbl),
+
+ /*
+ * Supervisor Call, and coprocessor instructions
+ */
+
+ /* MCRR cccc 1100 0100 xxxx xxxx xxxx xxxx xxxx */
+ /* MRRC cccc 1100 0101 xxxx xxxx xxxx xxxx xxxx */
+ /* LDC cccc 110x xxx1 xxxx xxxx xxxx xxxx xxxx */
+ /* STC cccc 110x xxx0 xxxx xxxx xxxx xxxx xxxx */
+ /* CDP cccc 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */
+ /* MCR cccc 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */
+ /* MRC cccc 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */
+ /* SVC cccc 1111 xxxx xxxx xxxx xxxx xxxx xxxx */
+ DECODE_REJECT (0x0c000000, 0x0c000000),
+
+ DECODE_END
+};
+#ifdef CONFIG_ARM_KPROBES_TEST_MODULE
+EXPORT_SYMBOL_GPL(kprobe_decode_arm_table);
+#endif
+
+static void __kprobes arm_singlestep(struct kprobe *p, struct pt_regs *regs)
+{
+ regs->ARM_pc += 4;
+ p->ainsn.insn_handler(p, regs);
+}
+
+/* Return:
+ * INSN_REJECTED If instruction is one not allowed to kprobe,
+ * INSN_GOOD If instruction is supported and uses instruction slot,
+ * INSN_GOOD_NO_SLOT If instruction is supported but doesn't use its slot.
+ *
+ * For instructions we don't want to kprobe (INSN_REJECTED return result):
+ * These are generally ones that modify the processor state making
+ * them "hard" to simulate such as switches processor modes or
+ * make accesses in alternate modes. Any of these could be simulated
+ * if the work was put into it, but low return considering they
+ * should also be very rare.
+ */
+enum kprobe_insn __kprobes
+arm_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi)
+{
+ asi->insn_singlestep = arm_singlestep;
+ asi->insn_check_cc = kprobe_condition_checks[insn>>28];
+ return kprobe_decode_insn(insn, asi, kprobe_decode_arm_table, false);
+}
--- /dev/null
+/*
+ * arch/arm/kernel/probes-arm.h
+ *
+ * Copyright 2013 Linaro Ltd.
+ * Written by: David A. Long
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#ifndef _ARM_KERNEL_PROBES_ARM_H
+#define _ARM_KERNEL_PROBES_ARM_H
+
+void __kprobes simulate_bbl(struct kprobe *p, struct pt_regs *regs);
+void __kprobes simulate_blx1(struct kprobe *p, struct pt_regs *regs);
+void __kprobes simulate_blx2bx(struct kprobe *p, struct pt_regs *regs);
+void __kprobes simulate_mrs(struct kprobe *p, struct pt_regs *regs);
+void __kprobes simulate_mov_ipsp(struct kprobe *p, struct pt_regs *regs);
+
+void __kprobes emulate_ldrdstrd(struct kprobe *p, struct pt_regs *regs);
+void __kprobes emulate_ldr(struct kprobe *p, struct pt_regs *regs);
+void __kprobes emulate_str(struct kprobe *p, struct pt_regs *regs);
+void __kprobes emulate_rd12rn16rm0rs8_rwflags(struct kprobe *p,
+ struct pt_regs *regs);
+void __kprobes emulate_rd12rn16rm0_rwflags_nopc(struct kprobe *p,
+ struct pt_regs *regs);
+void __kprobes emulate_rd16rn12rm0rs8_rwflags_nopc(struct kprobe *p,
+ struct pt_regs *regs);
+void __kprobes emulate_rd12rm0_noflags_nopc(struct kprobe *p,
+ struct pt_regs *regs);
+void __kprobes emulate_rdlo12rdhi16rn0rm8_rwflags_nopc(struct kprobe *p,
+ struct pt_regs *regs);
+
+#endif
--- /dev/null
+/*
+ * arch/arm/kernel/probes.c
+ *
+ * Copyright (C) 2011 Jon Medhurst <tixy@yxit.co.uk>.
+ *
+ * Some contents moved here from arch/arm/include/asm/kprobes-arm.c which is
+ * Copyright (C) 2006, 2007 Motorola Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/kprobes.h>
+#include <asm/system_info.h>
+#include <asm/ptrace.h>
+#include <linux/bug.h>
+
+#include "kprobes.h"
+
+
+#ifndef find_str_pc_offset
+
+/*
+ * For STR and STM instructions, an ARM core may choose to use either
+ * a +8 or a +12 displacement from the current instruction's address.
+ * Whichever value is chosen for a given core, it must be the same for
+ * both instructions and may not change. This function measures it.
+ */
+
+int str_pc_offset;
+
+void __init find_str_pc_offset(void)
+{
+ int addr, scratch, ret;
+
+ __asm__ (
+ "sub %[ret], pc, #4 \n\t"
+ "str pc, %[addr] \n\t"
+ "ldr %[scr], %[addr] \n\t"
+ "sub %[ret], %[scr], %[ret] \n\t"
+ : [ret] "=r" (ret), [scr] "=r" (scratch), [addr] "+m" (addr));
+
+ str_pc_offset = ret;
+}
+
+#endif /* !find_str_pc_offset */
+
+
+#ifndef test_load_write_pc_interworking
+
+bool load_write_pc_interworks;
+
+void __init test_load_write_pc_interworking(void)
+{
+ int arch = cpu_architecture();
+ BUG_ON(arch == CPU_ARCH_UNKNOWN);
+ load_write_pc_interworks = arch >= CPU_ARCH_ARMv5T;
+}
+
+#endif /* !test_load_write_pc_interworking */
+
+
+#ifndef test_alu_write_pc_interworking
+
+bool alu_write_pc_interworks;
+
+void __init test_alu_write_pc_interworking(void)
+{
+ int arch = cpu_architecture();
+ BUG_ON(arch == CPU_ARCH_UNKNOWN);
+ alu_write_pc_interworks = arch >= CPU_ARCH_ARMv7;
+}
+
+#endif /* !test_alu_write_pc_interworking */
+
+
+void __init arm_kprobe_decode_init(void)
+{
+ find_str_pc_offset();
+ test_load_write_pc_interworking();
+ test_alu_write_pc_interworking();
+}
+
+
+static unsigned long __kprobes __check_eq(unsigned long cpsr)
+{
+ return cpsr & PSR_Z_BIT;
+}
+
+static unsigned long __kprobes __check_ne(unsigned long cpsr)
+{
+ return (~cpsr) & PSR_Z_BIT;
+}
+
+static unsigned long __kprobes __check_cs(unsigned long cpsr)
+{
+ return cpsr & PSR_C_BIT;
+}
+
+static unsigned long __kprobes __check_cc(unsigned long cpsr)
+{
+ return (~cpsr) & PSR_C_BIT;
+}
+
+static unsigned long __kprobes __check_mi(unsigned long cpsr)
+{
+ return cpsr & PSR_N_BIT;
+}
+
+static unsigned long __kprobes __check_pl(unsigned long cpsr)
+{
+ return (~cpsr) & PSR_N_BIT;
+}
+
+static unsigned long __kprobes __check_vs(unsigned long cpsr)
+{
+ return cpsr & PSR_V_BIT;
+}
+
+static unsigned long __kprobes __check_vc(unsigned long cpsr)
+{
+ return (~cpsr) & PSR_V_BIT;
+}
+
+static unsigned long __kprobes __check_hi(unsigned long cpsr)
+{
+ cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
+ return cpsr & PSR_C_BIT;
+}
+
+static unsigned long __kprobes __check_ls(unsigned long cpsr)
+{
+ cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
+ return (~cpsr) & PSR_C_BIT;
+}
+
+static unsigned long __kprobes __check_ge(unsigned long cpsr)
+{
+ cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+ return (~cpsr) & PSR_N_BIT;
+}
+
+static unsigned long __kprobes __check_lt(unsigned long cpsr)
+{
+ cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+ return cpsr & PSR_N_BIT;
+}
+
+static unsigned long __kprobes __check_gt(unsigned long cpsr)
+{
+ unsigned long temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+ temp |= (cpsr << 1); /* PSR_N_BIT |= PSR_Z_BIT */
+ return (~temp) & PSR_N_BIT;
+}
+
+static unsigned long __kprobes __check_le(unsigned long cpsr)
+{
+ unsigned long temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
+ temp |= (cpsr << 1); /* PSR_N_BIT |= PSR_Z_BIT */
+ return temp & PSR_N_BIT;
+}
+
+static unsigned long __kprobes __check_al(unsigned long cpsr)
+{
+ return true;
+}
+
+kprobe_check_cc * const kprobe_condition_checks[16] = {
+ &__check_eq, &__check_ne, &__check_cs, &__check_cc,
+ &__check_mi, &__check_pl, &__check_vs, &__check_vc,
+ &__check_hi, &__check_ls, &__check_ge, &__check_lt,
+ &__check_gt, &__check_le, &__check_al, &__check_al
+};
+
+
+void __kprobes kprobe_simulate_nop(struct kprobe *p, struct pt_regs *regs)
+{
+}
+
+void __kprobes kprobe_emulate_none(struct kprobe *p, struct pt_regs *regs)
+{
+ p->ainsn.insn_fn();
+}
+
+/*
+ * Prepare an instruction slot to receive an instruction for emulating.
+ * This is done by placing a subroutine return after the location where the
+ * instruction will be placed. We also modify ARM instructions to be
+ * unconditional as the condition code will already be checked before any
+ * emulation handler is called.
+ */
+static kprobe_opcode_t __kprobes
+prepare_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi,
+ bool thumb)
+{
+#ifdef CONFIG_THUMB2_KERNEL
+ if (thumb) {
+ u16 *thumb_insn = (u16 *)asi->insn;
+ thumb_insn[1] = 0x4770; /* Thumb bx lr */
+ thumb_insn[2] = 0x4770; /* Thumb bx lr */
+ return insn;
+ }
+ asi->insn[1] = 0xe12fff1e; /* ARM bx lr */
+#else
+ asi->insn[1] = 0xe1a0f00e; /* mov pc, lr */
+#endif
+ /* Make an ARM instruction unconditional */
+ if (insn < 0xe0000000)
+ insn = (insn | 0xe0000000) & ~0x10000000;
+ return insn;
+}
+
+/*
+ * Write a (probably modified) instruction into the slot previously prepared by
+ * prepare_emulated_insn
+ */
+static void __kprobes
+set_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi,
+ bool thumb)
+{
+#ifdef CONFIG_THUMB2_KERNEL
+ if (thumb) {
+ u16 *ip = (u16 *)asi->insn;
+ if (is_wide_instruction(insn))
+ *ip++ = insn >> 16;
+ *ip++ = insn;
+ return;
+ }
+#endif
+ asi->insn[0] = insn;
+}
+
+/*
+ * When we modify the register numbers encoded in an instruction to be emulated,
+ * the new values come from this define. For ARM and 32-bit Thumb instructions
+ * this gives...
+ *
+ * bit position 16 12 8 4 0
+ * ---------------+---+---+---+---+---+
+ * register r2 r0 r1 -- r3
+ */
+#define INSN_NEW_BITS 0x00020103
+
+/* Each nibble has same value as that at INSN_NEW_BITS bit 16 */
+#define INSN_SAMEAS16_BITS 0x22222222
+
+/*
+ * Validate and modify each of the registers encoded in an instruction.
+ *
+ * Each nibble in regs contains a value from enum decode_reg_type. For each
+ * non-zero value, the corresponding nibble in pinsn is validated and modified
+ * according to the type.
+ */
+static bool __kprobes decode_regs(kprobe_opcode_t *pinsn, u32 regs)
+{
+ kprobe_opcode_t insn = *pinsn;
+ kprobe_opcode_t mask = 0xf; /* Start at least significant nibble */
+
+ for (; regs != 0; regs >>= 4, mask <<= 4) {
+
+ kprobe_opcode_t new_bits = INSN_NEW_BITS;
+
+ switch (regs & 0xf) {
+
+ case REG_TYPE_NONE:
+ /* Nibble not a register, skip to next */
+ continue;
+
+ case REG_TYPE_ANY:
+ /* Any register is allowed */
+ break;
+
+ case REG_TYPE_SAMEAS16:
+ /* Replace register with same as at bit position 16 */
+ new_bits = INSN_SAMEAS16_BITS;
+ break;
+
+ case REG_TYPE_SP:
+ /* Only allow SP (R13) */
+ if ((insn ^ 0xdddddddd) & mask)
+ goto reject;
+ break;
+
+ case REG_TYPE_PC:
+ /* Only allow PC (R15) */
+ if ((insn ^ 0xffffffff) & mask)
+ goto reject;
+ break;
+
+ case REG_TYPE_NOSP:
+ /* Reject SP (R13) */
+ if (((insn ^ 0xdddddddd) & mask) == 0)
+ goto reject;
+ break;
+
+ case REG_TYPE_NOSPPC:
+ case REG_TYPE_NOSPPCX:
+ /* Reject SP and PC (R13 and R15) */
+ if (((insn ^ 0xdddddddd) & 0xdddddddd & mask) == 0)
+ goto reject;
+ break;
+
+ case REG_TYPE_NOPCWB:
+ if (!is_writeback(insn))
+ break; /* No writeback, so any register is OK */
+ /* fall through... */
+ case REG_TYPE_NOPC:
+ case REG_TYPE_NOPCX:
+ /* Reject PC (R15) */
+ if (((insn ^ 0xffffffff) & mask) == 0)
+ goto reject;
+ break;
+ }
+
+ /* Replace value of nibble with new register number... */
+ insn &= ~mask;
+ insn |= new_bits & mask;
+ }
+
+ *pinsn = insn;
+ return true;
+
+reject:
+ return false;
+}
+
+static const int decode_struct_sizes[NUM_DECODE_TYPES] = {
+ [DECODE_TYPE_TABLE] = sizeof(struct decode_table),
+ [DECODE_TYPE_CUSTOM] = sizeof(struct decode_custom),
+ [DECODE_TYPE_SIMULATE] = sizeof(struct decode_simulate),
+ [DECODE_TYPE_EMULATE] = sizeof(struct decode_emulate),
+ [DECODE_TYPE_OR] = sizeof(struct decode_or),
+ [DECODE_TYPE_REJECT] = sizeof(struct decode_reject)
+};
+
+/*
+ * kprobe_decode_insn operates on data tables in order to decode an ARM
+ * architecture instruction onto which a kprobe has been placed.
+ *
+ * These instruction decoding tables are a concatenation of entries each
+ * of which consist of one of the following structs:
+ *
+ * decode_table
+ * decode_custom
+ * decode_simulate
+ * decode_emulate
+ * decode_or
+ * decode_reject
+ *
+ * Each of these starts with a struct decode_header which has the following
+ * fields:
+ *
+ * type_regs
+ * mask
+ * value
+ *
+ * The least significant DECODE_TYPE_BITS of type_regs contains a value
+ * from enum decode_type, this indicates which of the decode_* structs
+ * the entry contains. The value DECODE_TYPE_END indicates the end of the
+ * table.
+ *
+ * When the table is parsed, each entry is checked in turn to see if it
+ * matches the instruction to be decoded using the test:
+ *
+ * (insn & mask) == value
+ *
+ * If no match is found before the end of the table is reached then decoding
+ * fails with INSN_REJECTED.
+ *
+ * When a match is found, decode_regs() is called to validate and modify each
+ * of the registers encoded in the instruction; the data it uses to do this
+ * is (type_regs >> DECODE_TYPE_BITS). A validation failure will cause decoding
+ * to fail with INSN_REJECTED.
+ *
+ * Once the instruction has passed the above tests, further processing
+ * depends on the type of the table entry's decode struct.
+ *
+ */
+int __kprobes
+kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi,
+ const union decode_item *table, bool thumb)
+{
+ const struct decode_header *h = (struct decode_header *)table;
+ const struct decode_header *next;
+ bool matched = false;
+
+ insn = prepare_emulated_insn(insn, asi, thumb);
+
+ for (;; h = next) {
+ enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK;
+ u32 regs = h->type_regs.bits >> DECODE_TYPE_BITS;
+
+ if (type == DECODE_TYPE_END)
+ return INSN_REJECTED;
+
+ next = (struct decode_header *)
+ ((uintptr_t)h + decode_struct_sizes[type]);
+
+ if (!matched && (insn & h->mask.bits) != h->value.bits)
+ continue;
+
+ if (!decode_regs(&insn, regs))
+ return INSN_REJECTED;
+
+ switch (type) {
+
+ case DECODE_TYPE_TABLE: {
+ struct decode_table *d = (struct decode_table *)h;
+ next = (struct decode_header *)d->table.table;
+ break;
+ }
+
+ case DECODE_TYPE_CUSTOM: {
+ struct decode_custom *d = (struct decode_custom *)h;
+ return (*d->decoder.decoder)(insn, asi);
+ }
+
+ case DECODE_TYPE_SIMULATE: {
+ struct decode_simulate *d = (struct decode_simulate *)h;
+ asi->insn_handler = d->handler.handler;
+ return INSN_GOOD_NO_SLOT;
+ }
+
+ case DECODE_TYPE_EMULATE: {
+ struct decode_emulate *d = (struct decode_emulate *)h;
+ asi->insn_handler = d->handler.handler;
+ set_emulated_insn(insn, asi, thumb);
+ return INSN_GOOD;
+ }
+
+ case DECODE_TYPE_OR:
+ matched = true;
+ break;
+
+ case DECODE_TYPE_REJECT:
+ default:
+ return INSN_REJECTED;
+ }
+ }
+}
--- /dev/null
+/*
+ * arch/arm/kernel/probes.h
+ *
+ * Copyright (C) 2011 Jon Medhurst <tixy@yxit.co.uk>.
+ *
+ * Some contents moved here from arch/arm/include/asm/kprobes.h which is
+ * Copyright (C) 2006, 2007 Motorola Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#ifndef _ARM_KERNEL_PROBES_H
+#define _ARM_KERNEL_PROBES_H
+
+#include <linux/types.h>
+#include <linux/stddef.h>
+#include <linux/kprobes.h>
+
+#if __LINUX_ARM_ARCH__ >= 7
+
+/* str_pc_offset is architecturally defined from ARMv7 onwards */
+#define str_pc_offset 8
+#define find_str_pc_offset()
+
+#else /* __LINUX_ARM_ARCH__ < 7 */
+
+/* We need a run-time check to determine str_pc_offset */
+extern int str_pc_offset;
+void __init find_str_pc_offset(void);
+
+#endif
+
+
+/*
+ * Update ITSTATE after normal execution of an IT block instruction.
+ *
+ * The 8 IT state bits are split into two parts in CPSR:
+ * ITSTATE<1:0> are in CPSR<26:25>
+ * ITSTATE<7:2> are in CPSR<15:10>
+ */
+static inline unsigned long it_advance(unsigned long cpsr)
+ {
+ if ((cpsr & 0x06000400) == 0) {
+ /* ITSTATE<2:0> == 0 means end of IT block, so clear IT state */
+ cpsr &= ~PSR_IT_MASK;
+ } else {
+ /* We need to shift left ITSTATE<4:0> */
+ const unsigned long mask = 0x06001c00; /* Mask ITSTATE<4:0> */
+ unsigned long it = cpsr & mask;
+ it <<= 1;
+ it |= it >> (27 - 10); /* Carry ITSTATE<2> to correct place */
+ it &= mask;
+ cpsr &= ~mask;
+ cpsr |= it;
+ }
+ return cpsr;
+}
+
+static inline void __kprobes bx_write_pc(long pcv, struct pt_regs *regs)
+{
+ long cpsr = regs->ARM_cpsr;
+ if (pcv & 0x1) {
+ cpsr |= PSR_T_BIT;
+ pcv &= ~0x1;
+ } else {
+ cpsr &= ~PSR_T_BIT;
+ pcv &= ~0x2; /* Avoid UNPREDICTABLE address allignment */
+ }
+ regs->ARM_cpsr = cpsr;
+ regs->ARM_pc = pcv;
+}
+
+
+#if __LINUX_ARM_ARCH__ >= 6
+
+/* Kernels built for >= ARMv6 should never run on <= ARMv5 hardware, so... */
+#define load_write_pc_interworks true
+#define test_load_write_pc_interworking()
+
+#else /* __LINUX_ARM_ARCH__ < 6 */
+
+/* We need run-time testing to determine if load_write_pc() should interwork. */
+extern bool load_write_pc_interworks;
+void __init test_load_write_pc_interworking(void);
+
+#endif
+
+static inline void __kprobes load_write_pc(long pcv, struct pt_regs *regs)
+{
+ if (load_write_pc_interworks)
+ bx_write_pc(pcv, regs);
+ else
+ regs->ARM_pc = pcv;
+}
+
+
+#if __LINUX_ARM_ARCH__ >= 7
+
+#define alu_write_pc_interworks true
+#define test_alu_write_pc_interworking()
+
+#elif __LINUX_ARM_ARCH__ <= 5
+
+/* Kernels built for <= ARMv5 should never run on >= ARMv6 hardware, so... */
+#define alu_write_pc_interworks false
+#define test_alu_write_pc_interworking()
+
+#else /* __LINUX_ARM_ARCH__ == 6 */
+
+/* We could be an ARMv6 binary on ARMv7 hardware so we need a run-time check. */
+extern bool alu_write_pc_interworks;
+void __init test_alu_write_pc_interworking(void);
+
+#endif /* __LINUX_ARM_ARCH__ == 6 */
+
+static inline void __kprobes alu_write_pc(long pcv, struct pt_regs *regs)
+{
+ if (alu_write_pc_interworks)
+ bx_write_pc(pcv, regs);
+ else
+ regs->ARM_pc = pcv;
+}
+
+
+void __kprobes kprobe_simulate_nop(struct kprobe *p, struct pt_regs *regs);
+void __kprobes kprobe_emulate_none(struct kprobe *p, struct pt_regs *regs);
+
+enum kprobe_insn __kprobes
+kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi);
+
+/*
+ * Test if load/store instructions writeback the address register.
+ * if P (bit 24) == 0 or W (bit 21) == 1
+ */
+#define is_writeback(insn) ((insn ^ 0x01000000) & 0x01200000)
+
+/*
+ * The following definitions and macros are used to build instruction
+ * decoding tables for use by kprobe_decode_insn.
+ *
+ * These tables are a concatenation of entries each of which consist of one of
+ * the decode_* structs. All of the fields in every type of decode structure
+ * are of the union type decode_item, therefore the entire decode table can be
+ * viewed as an array of these and declared like:
+ *
+ * static const union decode_item table_name[] = {};
+ *
+ * In order to construct each entry in the table, macros are used to
+ * initialise a number of sequential decode_item values in a layout which
+ * matches the relevant struct. E.g. DECODE_SIMULATE initialise a struct
+ * decode_simulate by initialising four decode_item objects like this...
+ *
+ * {.bits = _type},
+ * {.bits = _mask},
+ * {.bits = _value},
+ * {.handler = _handler},
+ *
+ * Initialising a specified member of the union means that the compiler
+ * will produce a warning if the argument is of an incorrect type.
+ *
+ * Below is a list of each of the macros used to initialise entries and a
+ * description of the action performed when that entry is matched to an
+ * instruction. A match is found when (instruction & mask) == value.
+ *
+ * DECODE_TABLE(mask, value, table)
+ * Instruction decoding jumps to parsing the new sub-table 'table'.
+ *
+ * DECODE_CUSTOM(mask, value, decoder)
+ * The custom function 'decoder' is called to the complete decoding
+ * of an instruction.
+ *
+ * DECODE_SIMULATE(mask, value, handler)
+ * Set the probes instruction handler to 'handler', this will be used
+ * to simulate the instruction when the probe is hit. Decoding returns
+ * with INSN_GOOD_NO_SLOT.
+ *
+ * DECODE_EMULATE(mask, value, handler)
+ * Set the probes instruction handler to 'handler', this will be used
+ * to emulate the instruction when the probe is hit. The modified
+ * instruction (see below) is placed in the probes instruction slot so it
+ * may be called by the emulation code. Decoding returns with INSN_GOOD.
+ *
+ * DECODE_REJECT(mask, value)
+ * Instruction decoding fails with INSN_REJECTED
+ *
+ * DECODE_OR(mask, value)
+ * This allows the mask/value test of multiple table entries to be
+ * logically ORed. Once an 'or' entry is matched the decoding action to
+ * be performed is that of the next entry which isn't an 'or'. E.g.
+ *
+ * DECODE_OR (mask1, value1)
+ * DECODE_OR (mask2, value2)
+ * DECODE_SIMULATE (mask3, value3, simulation_handler)
+ *
+ * This means that if any of the three mask/value pairs match the
+ * instruction being decoded, then 'simulation_handler' will be used
+ * for it.
+ *
+ * Both the SIMULATE and EMULATE macros have a second form which take an
+ * additional 'regs' argument.
+ *
+ * DECODE_SIMULATEX(mask, value, handler, regs)
+ * DECODE_EMULATEX (mask, value, handler, regs)
+ *
+ * These are used to specify what kind of CPU register is encoded in each of the
+ * least significant 5 nibbles of the instruction being decoded. The regs value
+ * is specified using the REGS macro, this takes any of the REG_TYPE_* values
+ * from enum decode_reg_type as arguments; only the '*' part of the name is
+ * given. E.g.
+ *
+ * REGS(0, ANY, NOPC, 0, ANY)
+ *
+ * This indicates an instruction is encoded like:
+ *
+ * bits 19..16 ignore
+ * bits 15..12 any register allowed here
+ * bits 11.. 8 any register except PC allowed here
+ * bits 7.. 4 ignore
+ * bits 3.. 0 any register allowed here
+ *
+ * This register specification is checked after a decode table entry is found to
+ * match an instruction (through the mask/value test). Any invalid register then
+ * found in the instruction will cause decoding to fail with INSN_REJECTED. In
+ * the above example this would happen if bits 11..8 of the instruction were
+ * 1111, indicating R15 or PC.
+ *
+ * As well as checking for legal combinations of registers, this data is also
+ * used to modify the registers encoded in the instructions so that an
+ * emulation routines can use it. (See decode_regs() and INSN_NEW_BITS.)
+ *
+ * Here is a real example which matches ARM instructions of the form
+ * "AND <Rd>,<Rn>,<Rm>,<shift> <Rs>"
+ *
+ * DECODE_EMULATEX (0x0e000090, 0x00000010, emulate_rd12rn16rm0rs8_rwflags,
+ * REGS(ANY, ANY, NOPC, 0, ANY)),
+ * ^ ^ ^ ^
+ * Rn Rd Rs Rm
+ *
+ * Decoding the instruction "AND R4, R5, R6, ASL R15" will be rejected because
+ * Rs == R15
+ *
+ * Decoding the instruction "AND R4, R5, R6, ASL R7" will be accepted and the
+ * instruction will be modified to "AND R0, R2, R3, ASL R1" and then placed into
+ * the kprobes instruction slot. This can then be called later by the handler
+ * function emulate_rd12rn16rm0rs8_rwflags in order to simulate the instruction.
+ */
+
+enum decode_type {
+ DECODE_TYPE_END,
+ DECODE_TYPE_TABLE,
+ DECODE_TYPE_CUSTOM,
+ DECODE_TYPE_SIMULATE,
+ DECODE_TYPE_EMULATE,
+ DECODE_TYPE_OR,
+ DECODE_TYPE_REJECT,
+ NUM_DECODE_TYPES /* Must be last enum */
+};
+
+#define DECODE_TYPE_BITS 4
+#define DECODE_TYPE_MASK ((1 << DECODE_TYPE_BITS) - 1)
+
+enum decode_reg_type {
+ REG_TYPE_NONE = 0, /* Not a register, ignore */
+ REG_TYPE_ANY, /* Any register allowed */
+ REG_TYPE_SAMEAS16, /* Register should be same as that at bits 19..16 */
+ REG_TYPE_SP, /* Register must be SP */
+ REG_TYPE_PC, /* Register must be PC */
+ REG_TYPE_NOSP, /* Register must not be SP */
+ REG_TYPE_NOSPPC, /* Register must not be SP or PC */
+ REG_TYPE_NOPC, /* Register must not be PC */
+ REG_TYPE_NOPCWB, /* No PC if load/store write-back flag also set */
+
+ /* The following types are used when the encoding for PC indicates
+ * another instruction form. This distiction only matters for test
+ * case coverage checks.
+ */
+ REG_TYPE_NOPCX, /* Register must not be PC */
+ REG_TYPE_NOSPPCX, /* Register must not be SP or PC */
+
+ /* Alias to allow '0' arg to be used in REGS macro. */
+ REG_TYPE_0 = REG_TYPE_NONE
+};
+
+#define REGS(r16, r12, r8, r4, r0) \
+ (((REG_TYPE_##r16) << 16) + \
+ ((REG_TYPE_##r12) << 12) + \
+ ((REG_TYPE_##r8) << 8) + \
+ ((REG_TYPE_##r4) << 4) + \
+ (REG_TYPE_##r0))
+
+union decode_item {
+ u32 bits;
+ const union decode_item *table;
+ kprobe_insn_handler_t *handler;
+ kprobe_decode_insn_t *decoder;
+};
+
+
+#define DECODE_END \
+ {.bits = DECODE_TYPE_END}
+
+
+struct decode_header {
+ union decode_item type_regs;
+ union decode_item mask;
+ union decode_item value;
+};
+
+#define DECODE_HEADER(_type, _mask, _value, _regs) \
+ {.bits = (_type) | ((_regs) << DECODE_TYPE_BITS)}, \
+ {.bits = (_mask)}, \
+ {.bits = (_value)}
+
+
+struct decode_table {
+ struct decode_header header;
+ union decode_item table;
+};
+
+#define DECODE_TABLE(_mask, _value, _table) \
+ DECODE_HEADER(DECODE_TYPE_TABLE, _mask, _value, 0), \
+ {.table = (_table)}
+
+
+struct decode_custom {
+ struct decode_header header;
+ union decode_item decoder;
+};
+
+#define DECODE_CUSTOM(_mask, _value, _decoder) \
+ DECODE_HEADER(DECODE_TYPE_CUSTOM, _mask, _value, 0), \
+ {.decoder = (_decoder)}
+
+
+struct decode_simulate {
+ struct decode_header header;
+ union decode_item handler;
+};
+
+#define DECODE_SIMULATEX(_mask, _value, _handler, _regs) \
+ DECODE_HEADER(DECODE_TYPE_SIMULATE, _mask, _value, _regs), \
+ {.handler = (_handler)}
+
+#define DECODE_SIMULATE(_mask, _value, _handler) \
+ DECODE_SIMULATEX(_mask, _value, _handler, 0)
+
+
+struct decode_emulate {
+ struct decode_header header;
+ union decode_item handler;
+};
+
+#define DECODE_EMULATEX(_mask, _value, _handler, _regs) \
+ DECODE_HEADER(DECODE_TYPE_EMULATE, _mask, _value, _regs), \
+ {.handler = (_handler)}
+
+#define DECODE_EMULATE(_mask, _value, _handler) \
+ DECODE_EMULATEX(_mask, _value, _handler, 0)
+
+
+struct decode_or {
+ struct decode_header header;
+};
+
+#define DECODE_OR(_mask, _value) \
+ DECODE_HEADER(DECODE_TYPE_OR, _mask, _value, 0)
+
+
+struct decode_reject {
+ struct decode_header header;
+};
+
+#define DECODE_REJECT(_mask, _value) \
+ DECODE_HEADER(DECODE_TYPE_REJECT, _mask, _value, 0)
+
+
+#ifdef CONFIG_THUMB2_KERNEL
+extern const union decode_item kprobe_decode_thumb16_table[];
+extern const union decode_item kprobe_decode_thumb32_table[];
+#else
+extern const union decode_item kprobe_decode_arm_table[];
+#endif
+
+extern kprobe_check_cc * const kprobe_condition_checks[16];
+
+
+int kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi,
+ const union decode_item *table, bool thumb16);
+
+#endif
projects / openwrt / staging / blogic.git / commitdiff