extra-y := head.o init_task.o vmlinux.lds
obj-y := process.o signal_32.o entry.o traps_32.o irq.o \
- ptrace.o time_32.o ioport_32.o ldt.o setup_32.o i8259_32.o sys_i386_32.o \
+ ptrace_32.o time_32.o ioport_32.o ldt.o setup_32.o i8259_32.o sys_i386_32.o \
pci-dma_32.o i386_ksyms_32.o i387_32.o bootflag.o e820_32.o\
quirks.o i8237.o topology.o alternative.o i8253_32.o tsc.o
+++ /dev/null
-/* ptrace.c */
-/* By Ross Biro 1/23/92 */
-/*
- * Pentium III FXSR, SSE support
- * Gareth Hughes <gareth@valinux.com>, May 2000
- */
-
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/mm.h>
-#include <linux/smp.h>
-#include <linux/errno.h>
-#include <linux/ptrace.h>
-#include <linux/user.h>
-#include <linux/security.h>
-#include <linux/audit.h>
-#include <linux/seccomp.h>
-#include <linux/signal.h>
-
-#include <asm/uaccess.h>
-#include <asm/pgtable.h>
-#include <asm/system.h>
-#include <asm/processor.h>
-#include <asm/i387.h>
-#include <asm/debugreg.h>
-#include <asm/ldt.h>
-#include <asm/desc.h>
-
-/*
- * does not yet catch signals sent when the child dies.
- * in exit.c or in signal.c.
- */
-
-/*
- * Determines which flags the user has access to [1 = access, 0 = no access].
- * Prohibits changing ID(21), VIP(20), VIF(19), VM(17), NT(14), IOPL(12-13), IF(9).
- * Also masks reserved bits (31-22, 15, 5, 3, 1).
- */
-#define FLAG_MASK 0x00050dd5
-
-/* set's the trap flag. */
-#define TRAP_FLAG 0x100
-
-/*
- * Offset of eflags on child stack..
- */
-#define EFL_OFFSET offsetof(struct pt_regs, eflags)
-
-static inline struct pt_regs *get_child_regs(struct task_struct *task)
-{
- void *stack_top = (void *)task->thread.esp0;
- return stack_top - sizeof(struct pt_regs);
-}
-
-/*
- * This routine will get a word off of the processes privileged stack.
- * the offset is bytes into the pt_regs structure on the stack.
- * This routine assumes that all the privileged stacks are in our
- * data space.
- */
-static inline int get_stack_long(struct task_struct *task, int offset)
-{
- unsigned char *stack;
-
- stack = (unsigned char *)task->thread.esp0 - sizeof(struct pt_regs);
- stack += offset;
- return (*((int *)stack));
-}
-
-/*
- * This routine will put a word on the processes privileged stack.
- * the offset is bytes into the pt_regs structure on the stack.
- * This routine assumes that all the privileged stacks are in our
- * data space.
- */
-static inline int put_stack_long(struct task_struct *task, int offset,
- unsigned long data)
-{
- unsigned char * stack;
-
- stack = (unsigned char *)task->thread.esp0 - sizeof(struct pt_regs);
- stack += offset;
- *(unsigned long *) stack = data;
- return 0;
-}
-
-static int putreg(struct task_struct *child,
- unsigned long regno, unsigned long value)
-{
- switch (regno >> 2) {
- case GS:
- if (value && (value & 3) != 3)
- return -EIO;
- child->thread.gs = value;
- return 0;
- case DS:
- case ES:
- case FS:
- if (value && (value & 3) != 3)
- return -EIO;
- value &= 0xffff;
- break;
- case SS:
- case CS:
- if ((value & 3) != 3)
- return -EIO;
- value &= 0xffff;
- break;
- case EFL:
- value &= FLAG_MASK;
- value |= get_stack_long(child, EFL_OFFSET) & ~FLAG_MASK;
- break;
- }
- if (regno > FS*4)
- regno -= 1*4;
- put_stack_long(child, regno, value);
- return 0;
-}
-
-static unsigned long getreg(struct task_struct *child,
- unsigned long regno)
-{
- unsigned long retval = ~0UL;
-
- switch (regno >> 2) {
- case GS:
- retval = child->thread.gs;
- break;
- case DS:
- case ES:
- case FS:
- case SS:
- case CS:
- retval = 0xffff;
- /* fall through */
- default:
- if (regno > FS*4)
- regno -= 1*4;
- retval &= get_stack_long(child, regno);
- }
- return retval;
-}
-
-#define LDT_SEGMENT 4
-
-static unsigned long convert_eip_to_linear(struct task_struct *child, struct pt_regs *regs)
-{
- unsigned long addr, seg;
-
- addr = regs->eip;
- seg = regs->xcs & 0xffff;
- if (regs->eflags & VM_MASK) {
- addr = (addr & 0xffff) + (seg << 4);
- return addr;
- }
-
- /*
- * We'll assume that the code segments in the GDT
- * are all zero-based. That is largely true: the
- * TLS segments are used for data, and the PNPBIOS
- * and APM bios ones we just ignore here.
- */
- if (seg & LDT_SEGMENT) {
- u32 *desc;
- unsigned long base;
-
- seg &= ~7UL;
-
- down(&child->mm->context.sem);
- if (unlikely((seg >> 3) >= child->mm->context.size))
- addr = -1L; /* bogus selector, access would fault */
- else {
- desc = child->mm->context.ldt + seg;
- base = ((desc[0] >> 16) |
- ((desc[1] & 0xff) << 16) |
- (desc[1] & 0xff000000));
-
- /* 16-bit code segment? */
- if (!((desc[1] >> 22) & 1))
- addr &= 0xffff;
- addr += base;
- }
- up(&child->mm->context.sem);
- }
- return addr;
-}
-
-static inline int is_setting_trap_flag(struct task_struct *child, struct pt_regs *regs)
-{
- int i, copied;
- unsigned char opcode[15];
- unsigned long addr = convert_eip_to_linear(child, regs);
-
- copied = access_process_vm(child, addr, opcode, sizeof(opcode), 0);
- for (i = 0; i < copied; i++) {
- switch (opcode[i]) {
- /* popf and iret */
- case 0x9d: case 0xcf:
- return 1;
- /* opcode and address size prefixes */
- case 0x66: case 0x67:
- continue;
- /* irrelevant prefixes (segment overrides and repeats) */
- case 0x26: case 0x2e:
- case 0x36: case 0x3e:
- case 0x64: case 0x65:
- case 0xf0: case 0xf2: case 0xf3:
- continue;
-
- /*
- * pushf: NOTE! We should probably not let
- * the user see the TF bit being set. But
- * it's more pain than it's worth to avoid
- * it, and a debugger could emulate this
- * all in user space if it _really_ cares.
- */
- case 0x9c:
- default:
- return 0;
- }
- }
- return 0;
-}
-
-static void set_singlestep(struct task_struct *child)
-{
- struct pt_regs *regs = get_child_regs(child);
-
- /*
- * Always set TIF_SINGLESTEP - this guarantees that
- * we single-step system calls etc.. This will also
- * cause us to set TF when returning to user mode.
- */
- set_tsk_thread_flag(child, TIF_SINGLESTEP);
-
- /*
- * If TF was already set, don't do anything else
- */
- if (regs->eflags & TRAP_FLAG)
- return;
-
- /* Set TF on the kernel stack.. */
- regs->eflags |= TRAP_FLAG;
-
- /*
- * ..but if TF is changed by the instruction we will trace,
- * don't mark it as being "us" that set it, so that we
- * won't clear it by hand later.
- */
- if (is_setting_trap_flag(child, regs))
- return;
-
- child->ptrace |= PT_DTRACE;
-}
-
-static void clear_singlestep(struct task_struct *child)
-{
- /* Always clear TIF_SINGLESTEP... */
- clear_tsk_thread_flag(child, TIF_SINGLESTEP);
-
- /* But touch TF only if it was set by us.. */
- if (child->ptrace & PT_DTRACE) {
- struct pt_regs *regs = get_child_regs(child);
- regs->eflags &= ~TRAP_FLAG;
- child->ptrace &= ~PT_DTRACE;
- }
-}
-
-/*
- * Called by kernel/ptrace.c when detaching..
- *
- * Make sure the single step bit is not set.
- */
-void ptrace_disable(struct task_struct *child)
-{
- clear_singlestep(child);
- clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
-}
-
-/*
- * Perform get_thread_area on behalf of the traced child.
- */
-static int
-ptrace_get_thread_area(struct task_struct *child,
- int idx, struct user_desc __user *user_desc)
-{
- struct user_desc info;
- struct desc_struct *desc;
-
-/*
- * Get the current Thread-Local Storage area:
- */
-
-#define GET_BASE(desc) ( \
- (((desc)->a >> 16) & 0x0000ffff) | \
- (((desc)->b << 16) & 0x00ff0000) | \
- ( (desc)->b & 0xff000000) )
-
-#define GET_LIMIT(desc) ( \
- ((desc)->a & 0x0ffff) | \
- ((desc)->b & 0xf0000) )
-
-#define GET_32BIT(desc) (((desc)->b >> 22) & 1)
-#define GET_CONTENTS(desc) (((desc)->b >> 10) & 3)
-#define GET_WRITABLE(desc) (((desc)->b >> 9) & 1)
-#define GET_LIMIT_PAGES(desc) (((desc)->b >> 23) & 1)
-#define GET_PRESENT(desc) (((desc)->b >> 15) & 1)
-#define GET_USEABLE(desc) (((desc)->b >> 20) & 1)
-
- if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
- return -EINVAL;
-
- desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
-
- info.entry_number = idx;
- info.base_addr = GET_BASE(desc);
- info.limit = GET_LIMIT(desc);
- info.seg_32bit = GET_32BIT(desc);
- info.contents = GET_CONTENTS(desc);
- info.read_exec_only = !GET_WRITABLE(desc);
- info.limit_in_pages = GET_LIMIT_PAGES(desc);
- info.seg_not_present = !GET_PRESENT(desc);
- info.useable = GET_USEABLE(desc);
-
- if (copy_to_user(user_desc, &info, sizeof(info)))
- return -EFAULT;
-
- return 0;
-}
-
-/*
- * Perform set_thread_area on behalf of the traced child.
- */
-static int
-ptrace_set_thread_area(struct task_struct *child,
- int idx, struct user_desc __user *user_desc)
-{
- struct user_desc info;
- struct desc_struct *desc;
-
- if (copy_from_user(&info, user_desc, sizeof(info)))
- return -EFAULT;
-
- if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
- return -EINVAL;
-
- desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
- if (LDT_empty(&info)) {
- desc->a = 0;
- desc->b = 0;
- } else {
- desc->a = LDT_entry_a(&info);
- desc->b = LDT_entry_b(&info);
- }
-
- return 0;
-}
-
-long arch_ptrace(struct task_struct *child, long request, long addr, long data)
-{
- struct user * dummy = NULL;
- int i, ret;
- unsigned long __user *datap = (unsigned long __user *)data;
-
- switch (request) {
- /* when I and D space are separate, these will need to be fixed. */
- case PTRACE_PEEKTEXT: /* read word at location addr. */
- case PTRACE_PEEKDATA:
- ret = generic_ptrace_peekdata(child, addr, data);
- break;
-
- /* read the word at location addr in the USER area. */
- case PTRACE_PEEKUSR: {
- unsigned long tmp;
-
- ret = -EIO;
- if ((addr & 3) || addr < 0 ||
- addr > sizeof(struct user) - 3)
- break;
-
- tmp = 0; /* Default return condition */
- if(addr < FRAME_SIZE*sizeof(long))
- tmp = getreg(child, addr);
- if(addr >= (long) &dummy->u_debugreg[0] &&
- addr <= (long) &dummy->u_debugreg[7]){
- addr -= (long) &dummy->u_debugreg[0];
- addr = addr >> 2;
- tmp = child->thread.debugreg[addr];
- }
- ret = put_user(tmp, datap);
- break;
- }
-
- /* when I and D space are separate, this will have to be fixed. */
- case PTRACE_POKETEXT: /* write the word at location addr. */
- case PTRACE_POKEDATA:
- ret = generic_ptrace_pokedata(child, addr, data);
- break;
-
- case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
- ret = -EIO;
- if ((addr & 3) || addr < 0 ||
- addr > sizeof(struct user) - 3)
- break;
-
- if (addr < FRAME_SIZE*sizeof(long)) {
- ret = putreg(child, addr, data);
- break;
- }
- /* We need to be very careful here. We implicitly
- want to modify a portion of the task_struct, and we
- have to be selective about what portions we allow someone
- to modify. */
-
- ret = -EIO;
- if(addr >= (long) &dummy->u_debugreg[0] &&
- addr <= (long) &dummy->u_debugreg[7]){
-
- if(addr == (long) &dummy->u_debugreg[4]) break;
- if(addr == (long) &dummy->u_debugreg[5]) break;
- if(addr < (long) &dummy->u_debugreg[4] &&
- ((unsigned long) data) >= TASK_SIZE-3) break;
-
- /* Sanity-check data. Take one half-byte at once with
- * check = (val >> (16 + 4*i)) & 0xf. It contains the
- * R/Wi and LENi bits; bits 0 and 1 are R/Wi, and bits
- * 2 and 3 are LENi. Given a list of invalid values,
- * we do mask |= 1 << invalid_value, so that
- * (mask >> check) & 1 is a correct test for invalid
- * values.
- *
- * R/Wi contains the type of the breakpoint /
- * watchpoint, LENi contains the length of the watched
- * data in the watchpoint case.
- *
- * The invalid values are:
- * - LENi == 0x10 (undefined), so mask |= 0x0f00.
- * - R/Wi == 0x10 (break on I/O reads or writes), so
- * mask |= 0x4444.
- * - R/Wi == 0x00 && LENi != 0x00, so we have mask |=
- * 0x1110.
- *
- * Finally, mask = 0x0f00 | 0x4444 | 0x1110 == 0x5f54.
- *
- * See the Intel Manual "System Programming Guide",
- * 15.2.4
- *
- * Note that LENi == 0x10 is defined on x86_64 in long
- * mode (i.e. even for 32-bit userspace software, but
- * 64-bit kernel), so the x86_64 mask value is 0x5454.
- * See the AMD manual no. 24593 (AMD64 System
- * Programming)*/
-
- if(addr == (long) &dummy->u_debugreg[7]) {
- data &= ~DR_CONTROL_RESERVED;
- for(i=0; i<4; i++)
- if ((0x5f54 >> ((data >> (16 + 4*i)) & 0xf)) & 1)
- goto out_tsk;
- if (data)
- set_tsk_thread_flag(child, TIF_DEBUG);
- else
- clear_tsk_thread_flag(child, TIF_DEBUG);
- }
- addr -= (long) &dummy->u_debugreg;
- addr = addr >> 2;
- child->thread.debugreg[addr] = data;
- ret = 0;
- }
- break;
-
- case PTRACE_SYSEMU: /* continue and stop at next syscall, which will not be executed */
- case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
- case PTRACE_CONT: /* restart after signal. */
- ret = -EIO;
- if (!valid_signal(data))
- break;
- if (request == PTRACE_SYSEMU) {
- set_tsk_thread_flag(child, TIF_SYSCALL_EMU);
- clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
- } else if (request == PTRACE_SYSCALL) {
- set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
- clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
- } else {
- clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
- clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
- }
- child->exit_code = data;
- /* make sure the single step bit is not set. */
- clear_singlestep(child);
- wake_up_process(child);
- ret = 0;
- break;
-
-/*
- * make the child exit. Best I can do is send it a sigkill.
- * perhaps it should be put in the status that it wants to
- * exit.
- */
- case PTRACE_KILL:
- ret = 0;
- if (child->exit_state == EXIT_ZOMBIE) /* already dead */
- break;
- child->exit_code = SIGKILL;
- /* make sure the single step bit is not set. */
- clear_singlestep(child);
- wake_up_process(child);
- break;
-
- case PTRACE_SYSEMU_SINGLESTEP: /* Same as SYSEMU, but singlestep if not syscall */
- case PTRACE_SINGLESTEP: /* set the trap flag. */
- ret = -EIO;
- if (!valid_signal(data))
- break;
-
- if (request == PTRACE_SYSEMU_SINGLESTEP)
- set_tsk_thread_flag(child, TIF_SYSCALL_EMU);
- else
- clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
-
- clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
- set_singlestep(child);
- child->exit_code = data;
- /* give it a chance to run. */
- wake_up_process(child);
- ret = 0;
- break;
-
- case PTRACE_DETACH:
- /* detach a process that was attached. */
- ret = ptrace_detach(child, data);
- break;
-
- case PTRACE_GETREGS: { /* Get all gp regs from the child. */
- if (!access_ok(VERIFY_WRITE, datap, FRAME_SIZE*sizeof(long))) {
- ret = -EIO;
- break;
- }
- for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
- __put_user(getreg(child, i), datap);
- datap++;
- }
- ret = 0;
- break;
- }
-
- case PTRACE_SETREGS: { /* Set all gp regs in the child. */
- unsigned long tmp;
- if (!access_ok(VERIFY_READ, datap, FRAME_SIZE*sizeof(long))) {
- ret = -EIO;
- break;
- }
- for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
- __get_user(tmp, datap);
- putreg(child, i, tmp);
- datap++;
- }
- ret = 0;
- break;
- }
-
- case PTRACE_GETFPREGS: { /* Get the child FPU state. */
- if (!access_ok(VERIFY_WRITE, datap,
- sizeof(struct user_i387_struct))) {
- ret = -EIO;
- break;
- }
- ret = 0;
- if (!tsk_used_math(child))
- init_fpu(child);
- get_fpregs((struct user_i387_struct __user *)data, child);
- break;
- }
-
- case PTRACE_SETFPREGS: { /* Set the child FPU state. */
- if (!access_ok(VERIFY_READ, datap,
- sizeof(struct user_i387_struct))) {
- ret = -EIO;
- break;
- }
- set_stopped_child_used_math(child);
- set_fpregs(child, (struct user_i387_struct __user *)data);
- ret = 0;
- break;
- }
-
- case PTRACE_GETFPXREGS: { /* Get the child extended FPU state. */
- if (!access_ok(VERIFY_WRITE, datap,
- sizeof(struct user_fxsr_struct))) {
- ret = -EIO;
- break;
- }
- if (!tsk_used_math(child))
- init_fpu(child);
- ret = get_fpxregs((struct user_fxsr_struct __user *)data, child);
- break;
- }
-
- case PTRACE_SETFPXREGS: { /* Set the child extended FPU state. */
- if (!access_ok(VERIFY_READ, datap,
- sizeof(struct user_fxsr_struct))) {
- ret = -EIO;
- break;
- }
- set_stopped_child_used_math(child);
- ret = set_fpxregs(child, (struct user_fxsr_struct __user *)data);
- break;
- }
-
- case PTRACE_GET_THREAD_AREA:
- ret = ptrace_get_thread_area(child, addr,
- (struct user_desc __user *) data);
- break;
-
- case PTRACE_SET_THREAD_AREA:
- ret = ptrace_set_thread_area(child, addr,
- (struct user_desc __user *) data);
- break;
-
- default:
- ret = ptrace_request(child, request, addr, data);
- break;
- }
- out_tsk:
- return ret;
-}
-
-void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)
-{
- struct siginfo info;
-
- tsk->thread.trap_no = 1;
- tsk->thread.error_code = error_code;
-
- memset(&info, 0, sizeof(info));
- info.si_signo = SIGTRAP;
- info.si_code = TRAP_BRKPT;
-
- /* User-mode eip? */
- info.si_addr = user_mode_vm(regs) ? (void __user *) regs->eip : NULL;
-
- /* Send us the fakey SIGTRAP */
- force_sig_info(SIGTRAP, &info, tsk);
-}
-
-/* notification of system call entry/exit
- * - triggered by current->work.syscall_trace
- */
-__attribute__((regparm(3)))
-int do_syscall_trace(struct pt_regs *regs, int entryexit)
-{
- int is_sysemu = test_thread_flag(TIF_SYSCALL_EMU);
- /*
- * With TIF_SYSCALL_EMU set we want to ignore TIF_SINGLESTEP for syscall
- * interception
- */
- int is_singlestep = !is_sysemu && test_thread_flag(TIF_SINGLESTEP);
- int ret = 0;
-
- /* do the secure computing check first */
- if (!entryexit)
- secure_computing(regs->orig_eax);
-
- if (unlikely(current->audit_context)) {
- if (entryexit)
- audit_syscall_exit(AUDITSC_RESULT(regs->eax),
- regs->eax);
- /* Debug traps, when using PTRACE_SINGLESTEP, must be sent only
- * on the syscall exit path. Normally, when TIF_SYSCALL_AUDIT is
- * not used, entry.S will call us only on syscall exit, not
- * entry; so when TIF_SYSCALL_AUDIT is used we must avoid
- * calling send_sigtrap() on syscall entry.
- *
- * Note that when PTRACE_SYSEMU_SINGLESTEP is used,
- * is_singlestep is false, despite his name, so we will still do
- * the correct thing.
- */
- else if (is_singlestep)
- goto out;
- }
-
- if (!(current->ptrace & PT_PTRACED))
- goto out;
-
- /* If a process stops on the 1st tracepoint with SYSCALL_TRACE
- * and then is resumed with SYSEMU_SINGLESTEP, it will come in
- * here. We have to check this and return */
- if (is_sysemu && entryexit)
- return 0;
-
- /* Fake a debug trap */
- if (is_singlestep)
- send_sigtrap(current, regs, 0);
-
- if (!test_thread_flag(TIF_SYSCALL_TRACE) && !is_sysemu)
- goto out;
-
- /* the 0x80 provides a way for the tracing parent to distinguish
- between a syscall stop and SIGTRAP delivery */
- /* Note that the debugger could change the result of test_thread_flag!*/
- ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) ? 0x80:0));
-
- /*
- * this isn't the same as continuing with a signal, but it will do
- * for normal use. strace only continues with a signal if the
- * stopping signal is not SIGTRAP. -brl
- */
- if (current->exit_code) {
- send_sig(current->exit_code, current, 1);
- current->exit_code = 0;
- }
- ret = is_sysemu;
-out:
- if (unlikely(current->audit_context) && !entryexit)
- audit_syscall_entry(AUDIT_ARCH_I386, regs->orig_eax,
- regs->ebx, regs->ecx, regs->edx, regs->esi);
- if (ret == 0)
- return 0;
-
- regs->orig_eax = -1; /* force skip of syscall restarting */
- if (unlikely(current->audit_context))
- audit_syscall_exit(AUDITSC_RESULT(regs->eax), regs->eax);
- return 1;
-}
--- /dev/null
+/* ptrace.c */
+/* By Ross Biro 1/23/92 */
+/*
+ * Pentium III FXSR, SSE support
+ * Gareth Hughes <gareth@valinux.com>, May 2000
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/security.h>
+#include <linux/audit.h>
+#include <linux/seccomp.h>
+#include <linux/signal.h>
+
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/processor.h>
+#include <asm/i387.h>
+#include <asm/debugreg.h>
+#include <asm/ldt.h>
+#include <asm/desc.h>
+
+/*
+ * does not yet catch signals sent when the child dies.
+ * in exit.c or in signal.c.
+ */
+
+/*
+ * Determines which flags the user has access to [1 = access, 0 = no access].
+ * Prohibits changing ID(21), VIP(20), VIF(19), VM(17), NT(14), IOPL(12-13), IF(9).
+ * Also masks reserved bits (31-22, 15, 5, 3, 1).
+ */
+#define FLAG_MASK 0x00050dd5
+
+/* set's the trap flag. */
+#define TRAP_FLAG 0x100
+
+/*
+ * Offset of eflags on child stack..
+ */
+#define EFL_OFFSET offsetof(struct pt_regs, eflags)
+
+static inline struct pt_regs *get_child_regs(struct task_struct *task)
+{
+ void *stack_top = (void *)task->thread.esp0;
+ return stack_top - sizeof(struct pt_regs);
+}
+
+/*
+ * This routine will get a word off of the processes privileged stack.
+ * the offset is bytes into the pt_regs structure on the stack.
+ * This routine assumes that all the privileged stacks are in our
+ * data space.
+ */
+static inline int get_stack_long(struct task_struct *task, int offset)
+{
+ unsigned char *stack;
+
+ stack = (unsigned char *)task->thread.esp0 - sizeof(struct pt_regs);
+ stack += offset;
+ return (*((int *)stack));
+}
+
+/*
+ * This routine will put a word on the processes privileged stack.
+ * the offset is bytes into the pt_regs structure on the stack.
+ * This routine assumes that all the privileged stacks are in our
+ * data space.
+ */
+static inline int put_stack_long(struct task_struct *task, int offset,
+ unsigned long data)
+{
+ unsigned char * stack;
+
+ stack = (unsigned char *)task->thread.esp0 - sizeof(struct pt_regs);
+ stack += offset;
+ *(unsigned long *) stack = data;
+ return 0;
+}
+
+static int putreg(struct task_struct *child,
+ unsigned long regno, unsigned long value)
+{
+ switch (regno >> 2) {
+ case GS:
+ if (value && (value & 3) != 3)
+ return -EIO;
+ child->thread.gs = value;
+ return 0;
+ case DS:
+ case ES:
+ case FS:
+ if (value && (value & 3) != 3)
+ return -EIO;
+ value &= 0xffff;
+ break;
+ case SS:
+ case CS:
+ if ((value & 3) != 3)
+ return -EIO;
+ value &= 0xffff;
+ break;
+ case EFL:
+ value &= FLAG_MASK;
+ value |= get_stack_long(child, EFL_OFFSET) & ~FLAG_MASK;
+ break;
+ }
+ if (regno > FS*4)
+ regno -= 1*4;
+ put_stack_long(child, regno, value);
+ return 0;
+}
+
+static unsigned long getreg(struct task_struct *child,
+ unsigned long regno)
+{
+ unsigned long retval = ~0UL;
+
+ switch (regno >> 2) {
+ case GS:
+ retval = child->thread.gs;
+ break;
+ case DS:
+ case ES:
+ case FS:
+ case SS:
+ case CS:
+ retval = 0xffff;
+ /* fall through */
+ default:
+ if (regno > FS*4)
+ regno -= 1*4;
+ retval &= get_stack_long(child, regno);
+ }
+ return retval;
+}
+
+#define LDT_SEGMENT 4
+
+static unsigned long convert_eip_to_linear(struct task_struct *child, struct pt_regs *regs)
+{
+ unsigned long addr, seg;
+
+ addr = regs->eip;
+ seg = regs->xcs & 0xffff;
+ if (regs->eflags & VM_MASK) {
+ addr = (addr & 0xffff) + (seg << 4);
+ return addr;
+ }
+
+ /*
+ * We'll assume that the code segments in the GDT
+ * are all zero-based. That is largely true: the
+ * TLS segments are used for data, and the PNPBIOS
+ * and APM bios ones we just ignore here.
+ */
+ if (seg & LDT_SEGMENT) {
+ u32 *desc;
+ unsigned long base;
+
+ seg &= ~7UL;
+
+ down(&child->mm->context.sem);
+ if (unlikely((seg >> 3) >= child->mm->context.size))
+ addr = -1L; /* bogus selector, access would fault */
+ else {
+ desc = child->mm->context.ldt + seg;
+ base = ((desc[0] >> 16) |
+ ((desc[1] & 0xff) << 16) |
+ (desc[1] & 0xff000000));
+
+ /* 16-bit code segment? */
+ if (!((desc[1] >> 22) & 1))
+ addr &= 0xffff;
+ addr += base;
+ }
+ up(&child->mm->context.sem);
+ }
+ return addr;
+}
+
+static inline int is_setting_trap_flag(struct task_struct *child, struct pt_regs *regs)
+{
+ int i, copied;
+ unsigned char opcode[15];
+ unsigned long addr = convert_eip_to_linear(child, regs);
+
+ copied = access_process_vm(child, addr, opcode, sizeof(opcode), 0);
+ for (i = 0; i < copied; i++) {
+ switch (opcode[i]) {
+ /* popf and iret */
+ case 0x9d: case 0xcf:
+ return 1;
+ /* opcode and address size prefixes */
+ case 0x66: case 0x67:
+ continue;
+ /* irrelevant prefixes (segment overrides and repeats) */
+ case 0x26: case 0x2e:
+ case 0x36: case 0x3e:
+ case 0x64: case 0x65:
+ case 0xf0: case 0xf2: case 0xf3:
+ continue;
+
+ /*
+ * pushf: NOTE! We should probably not let
+ * the user see the TF bit being set. But
+ * it's more pain than it's worth to avoid
+ * it, and a debugger could emulate this
+ * all in user space if it _really_ cares.
+ */
+ case 0x9c:
+ default:
+ return 0;
+ }
+ }
+ return 0;
+}
+
+static void set_singlestep(struct task_struct *child)
+{
+ struct pt_regs *regs = get_child_regs(child);
+
+ /*
+ * Always set TIF_SINGLESTEP - this guarantees that
+ * we single-step system calls etc.. This will also
+ * cause us to set TF when returning to user mode.
+ */
+ set_tsk_thread_flag(child, TIF_SINGLESTEP);
+
+ /*
+ * If TF was already set, don't do anything else
+ */
+ if (regs->eflags & TRAP_FLAG)
+ return;
+
+ /* Set TF on the kernel stack.. */
+ regs->eflags |= TRAP_FLAG;
+
+ /*
+ * ..but if TF is changed by the instruction we will trace,
+ * don't mark it as being "us" that set it, so that we
+ * won't clear it by hand later.
+ */
+ if (is_setting_trap_flag(child, regs))
+ return;
+
+ child->ptrace |= PT_DTRACE;
+}
+
+static void clear_singlestep(struct task_struct *child)
+{
+ /* Always clear TIF_SINGLESTEP... */
+ clear_tsk_thread_flag(child, TIF_SINGLESTEP);
+
+ /* But touch TF only if it was set by us.. */
+ if (child->ptrace & PT_DTRACE) {
+ struct pt_regs *regs = get_child_regs(child);
+ regs->eflags &= ~TRAP_FLAG;
+ child->ptrace &= ~PT_DTRACE;
+ }
+}
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure the single step bit is not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{
+ clear_singlestep(child);
+ clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
+}
+
+/*
+ * Perform get_thread_area on behalf of the traced child.
+ */
+static int
+ptrace_get_thread_area(struct task_struct *child,
+ int idx, struct user_desc __user *user_desc)
+{
+ struct user_desc info;
+ struct desc_struct *desc;
+
+/*
+ * Get the current Thread-Local Storage area:
+ */
+
+#define GET_BASE(desc) ( \
+ (((desc)->a >> 16) & 0x0000ffff) | \
+ (((desc)->b << 16) & 0x00ff0000) | \
+ ( (desc)->b & 0xff000000) )
+
+#define GET_LIMIT(desc) ( \
+ ((desc)->a & 0x0ffff) | \
+ ((desc)->b & 0xf0000) )
+
+#define GET_32BIT(desc) (((desc)->b >> 22) & 1)
+#define GET_CONTENTS(desc) (((desc)->b >> 10) & 3)
+#define GET_WRITABLE(desc) (((desc)->b >> 9) & 1)
+#define GET_LIMIT_PAGES(desc) (((desc)->b >> 23) & 1)
+#define GET_PRESENT(desc) (((desc)->b >> 15) & 1)
+#define GET_USEABLE(desc) (((desc)->b >> 20) & 1)
+
+ if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
+ return -EINVAL;
+
+ desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
+
+ info.entry_number = idx;
+ info.base_addr = GET_BASE(desc);
+ info.limit = GET_LIMIT(desc);
+ info.seg_32bit = GET_32BIT(desc);
+ info.contents = GET_CONTENTS(desc);
+ info.read_exec_only = !GET_WRITABLE(desc);
+ info.limit_in_pages = GET_LIMIT_PAGES(desc);
+ info.seg_not_present = !GET_PRESENT(desc);
+ info.useable = GET_USEABLE(desc);
+
+ if (copy_to_user(user_desc, &info, sizeof(info)))
+ return -EFAULT;
+
+ return 0;
+}
+
+/*
+ * Perform set_thread_area on behalf of the traced child.
+ */
+static int
+ptrace_set_thread_area(struct task_struct *child,
+ int idx, struct user_desc __user *user_desc)
+{
+ struct user_desc info;
+ struct desc_struct *desc;
+
+ if (copy_from_user(&info, user_desc, sizeof(info)))
+ return -EFAULT;
+
+ if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
+ return -EINVAL;
+
+ desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
+ if (LDT_empty(&info)) {
+ desc->a = 0;
+ desc->b = 0;
+ } else {
+ desc->a = LDT_entry_a(&info);
+ desc->b = LDT_entry_b(&info);
+ }
+
+ return 0;
+}
+
+long arch_ptrace(struct task_struct *child, long request, long addr, long data)
+{
+ struct user * dummy = NULL;
+ int i, ret;
+ unsigned long __user *datap = (unsigned long __user *)data;
+
+ switch (request) {
+ /* when I and D space are separate, these will need to be fixed. */
+ case PTRACE_PEEKTEXT: /* read word at location addr. */
+ case PTRACE_PEEKDATA:
+ ret = generic_ptrace_peekdata(child, addr, data);
+ break;
+
+ /* read the word at location addr in the USER area. */
+ case PTRACE_PEEKUSR: {
+ unsigned long tmp;
+
+ ret = -EIO;
+ if ((addr & 3) || addr < 0 ||
+ addr > sizeof(struct user) - 3)
+ break;
+
+ tmp = 0; /* Default return condition */
+ if(addr < FRAME_SIZE*sizeof(long))
+ tmp = getreg(child, addr);
+ if(addr >= (long) &dummy->u_debugreg[0] &&
+ addr <= (long) &dummy->u_debugreg[7]){
+ addr -= (long) &dummy->u_debugreg[0];
+ addr = addr >> 2;
+ tmp = child->thread.debugreg[addr];
+ }
+ ret = put_user(tmp, datap);
+ break;
+ }
+
+ /* when I and D space are separate, this will have to be fixed. */
+ case PTRACE_POKETEXT: /* write the word at location addr. */
+ case PTRACE_POKEDATA:
+ ret = generic_ptrace_pokedata(child, addr, data);
+ break;
+
+ case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
+ ret = -EIO;
+ if ((addr & 3) || addr < 0 ||
+ addr > sizeof(struct user) - 3)
+ break;
+
+ if (addr < FRAME_SIZE*sizeof(long)) {
+ ret = putreg(child, addr, data);
+ break;
+ }
+ /* We need to be very careful here. We implicitly
+ want to modify a portion of the task_struct, and we
+ have to be selective about what portions we allow someone
+ to modify. */
+
+ ret = -EIO;
+ if(addr >= (long) &dummy->u_debugreg[0] &&
+ addr <= (long) &dummy->u_debugreg[7]){
+
+ if(addr == (long) &dummy->u_debugreg[4]) break;
+ if(addr == (long) &dummy->u_debugreg[5]) break;
+ if(addr < (long) &dummy->u_debugreg[4] &&
+ ((unsigned long) data) >= TASK_SIZE-3) break;
+
+ /* Sanity-check data. Take one half-byte at once with
+ * check = (val >> (16 + 4*i)) & 0xf. It contains the
+ * R/Wi and LENi bits; bits 0 and 1 are R/Wi, and bits
+ * 2 and 3 are LENi. Given a list of invalid values,
+ * we do mask |= 1 << invalid_value, so that
+ * (mask >> check) & 1 is a correct test for invalid
+ * values.
+ *
+ * R/Wi contains the type of the breakpoint /
+ * watchpoint, LENi contains the length of the watched
+ * data in the watchpoint case.
+ *
+ * The invalid values are:
+ * - LENi == 0x10 (undefined), so mask |= 0x0f00.
+ * - R/Wi == 0x10 (break on I/O reads or writes), so
+ * mask |= 0x4444.
+ * - R/Wi == 0x00 && LENi != 0x00, so we have mask |=
+ * 0x1110.
+ *
+ * Finally, mask = 0x0f00 | 0x4444 | 0x1110 == 0x5f54.
+ *
+ * See the Intel Manual "System Programming Guide",
+ * 15.2.4
+ *
+ * Note that LENi == 0x10 is defined on x86_64 in long
+ * mode (i.e. even for 32-bit userspace software, but
+ * 64-bit kernel), so the x86_64 mask value is 0x5454.
+ * See the AMD manual no. 24593 (AMD64 System
+ * Programming)*/
+
+ if(addr == (long) &dummy->u_debugreg[7]) {
+ data &= ~DR_CONTROL_RESERVED;
+ for(i=0; i<4; i++)
+ if ((0x5f54 >> ((data >> (16 + 4*i)) & 0xf)) & 1)
+ goto out_tsk;
+ if (data)
+ set_tsk_thread_flag(child, TIF_DEBUG);
+ else
+ clear_tsk_thread_flag(child, TIF_DEBUG);
+ }
+ addr -= (long) &dummy->u_debugreg;
+ addr = addr >> 2;
+ child->thread.debugreg[addr] = data;
+ ret = 0;
+ }
+ break;
+
+ case PTRACE_SYSEMU: /* continue and stop at next syscall, which will not be executed */
+ case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
+ case PTRACE_CONT: /* restart after signal. */
+ ret = -EIO;
+ if (!valid_signal(data))
+ break;
+ if (request == PTRACE_SYSEMU) {
+ set_tsk_thread_flag(child, TIF_SYSCALL_EMU);
+ clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+ } else if (request == PTRACE_SYSCALL) {
+ set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+ clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
+ } else {
+ clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
+ clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+ }
+ child->exit_code = data;
+ /* make sure the single step bit is not set. */
+ clear_singlestep(child);
+ wake_up_process(child);
+ ret = 0;
+ break;
+
+/*
+ * make the child exit. Best I can do is send it a sigkill.
+ * perhaps it should be put in the status that it wants to
+ * exit.
+ */
+ case PTRACE_KILL:
+ ret = 0;
+ if (child->exit_state == EXIT_ZOMBIE) /* already dead */
+ break;
+ child->exit_code = SIGKILL;
+ /* make sure the single step bit is not set. */
+ clear_singlestep(child);
+ wake_up_process(child);
+ break;
+
+ case PTRACE_SYSEMU_SINGLESTEP: /* Same as SYSEMU, but singlestep if not syscall */
+ case PTRACE_SINGLESTEP: /* set the trap flag. */
+ ret = -EIO;
+ if (!valid_signal(data))
+ break;
+
+ if (request == PTRACE_SYSEMU_SINGLESTEP)
+ set_tsk_thread_flag(child, TIF_SYSCALL_EMU);
+ else
+ clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
+
+ clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+ set_singlestep(child);
+ child->exit_code = data;
+ /* give it a chance to run. */
+ wake_up_process(child);
+ ret = 0;
+ break;
+
+ case PTRACE_DETACH:
+ /* detach a process that was attached. */
+ ret = ptrace_detach(child, data);
+ break;
+
+ case PTRACE_GETREGS: { /* Get all gp regs from the child. */
+ if (!access_ok(VERIFY_WRITE, datap, FRAME_SIZE*sizeof(long))) {
+ ret = -EIO;
+ break;
+ }
+ for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
+ __put_user(getreg(child, i), datap);
+ datap++;
+ }
+ ret = 0;
+ break;
+ }
+
+ case PTRACE_SETREGS: { /* Set all gp regs in the child. */
+ unsigned long tmp;
+ if (!access_ok(VERIFY_READ, datap, FRAME_SIZE*sizeof(long))) {
+ ret = -EIO;
+ break;
+ }
+ for ( i = 0; i < FRAME_SIZE*sizeof(long); i += sizeof(long) ) {
+ __get_user(tmp, datap);
+ putreg(child, i, tmp);
+ datap++;
+ }
+ ret = 0;
+ break;
+ }
+
+ case PTRACE_GETFPREGS: { /* Get the child FPU state. */
+ if (!access_ok(VERIFY_WRITE, datap,
+ sizeof(struct user_i387_struct))) {
+ ret = -EIO;
+ break;
+ }
+ ret = 0;
+ if (!tsk_used_math(child))
+ init_fpu(child);
+ get_fpregs((struct user_i387_struct __user *)data, child);
+ break;
+ }
+
+ case PTRACE_SETFPREGS: { /* Set the child FPU state. */
+ if (!access_ok(VERIFY_READ, datap,
+ sizeof(struct user_i387_struct))) {
+ ret = -EIO;
+ break;
+ }
+ set_stopped_child_used_math(child);
+ set_fpregs(child, (struct user_i387_struct __user *)data);
+ ret = 0;
+ break;
+ }
+
+ case PTRACE_GETFPXREGS: { /* Get the child extended FPU state. */
+ if (!access_ok(VERIFY_WRITE, datap,
+ sizeof(struct user_fxsr_struct))) {
+ ret = -EIO;
+ break;
+ }
+ if (!tsk_used_math(child))
+ init_fpu(child);
+ ret = get_fpxregs((struct user_fxsr_struct __user *)data, child);
+ break;
+ }
+
+ case PTRACE_SETFPXREGS: { /* Set the child extended FPU state. */
+ if (!access_ok(VERIFY_READ, datap,
+ sizeof(struct user_fxsr_struct))) {
+ ret = -EIO;
+ break;
+ }
+ set_stopped_child_used_math(child);
+ ret = set_fpxregs(child, (struct user_fxsr_struct __user *)data);
+ break;
+ }
+
+ case PTRACE_GET_THREAD_AREA:
+ ret = ptrace_get_thread_area(child, addr,
+ (struct user_desc __user *) data);
+ break;
+
+ case PTRACE_SET_THREAD_AREA:
+ ret = ptrace_set_thread_area(child, addr,
+ (struct user_desc __user *) data);
+ break;
+
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+ out_tsk:
+ return ret;
+}
+
+void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)
+{
+ struct siginfo info;
+
+ tsk->thread.trap_no = 1;
+ tsk->thread.error_code = error_code;
+
+ memset(&info, 0, sizeof(info));
+ info.si_signo = SIGTRAP;
+ info.si_code = TRAP_BRKPT;
+
+ /* User-mode eip? */
+ info.si_addr = user_mode_vm(regs) ? (void __user *) regs->eip : NULL;
+
+ /* Send us the fakey SIGTRAP */
+ force_sig_info(SIGTRAP, &info, tsk);
+}
+
+/* notification of system call entry/exit
+ * - triggered by current->work.syscall_trace
+ */
+__attribute__((regparm(3)))
+int do_syscall_trace(struct pt_regs *regs, int entryexit)
+{
+ int is_sysemu = test_thread_flag(TIF_SYSCALL_EMU);
+ /*
+ * With TIF_SYSCALL_EMU set we want to ignore TIF_SINGLESTEP for syscall
+ * interception
+ */
+ int is_singlestep = !is_sysemu && test_thread_flag(TIF_SINGLESTEP);
+ int ret = 0;
+
+ /* do the secure computing check first */
+ if (!entryexit)
+ secure_computing(regs->orig_eax);
+
+ if (unlikely(current->audit_context)) {
+ if (entryexit)
+ audit_syscall_exit(AUDITSC_RESULT(regs->eax),
+ regs->eax);
+ /* Debug traps, when using PTRACE_SINGLESTEP, must be sent only
+ * on the syscall exit path. Normally, when TIF_SYSCALL_AUDIT is
+ * not used, entry.S will call us only on syscall exit, not
+ * entry; so when TIF_SYSCALL_AUDIT is used we must avoid
+ * calling send_sigtrap() on syscall entry.
+ *
+ * Note that when PTRACE_SYSEMU_SINGLESTEP is used,
+ * is_singlestep is false, despite his name, so we will still do
+ * the correct thing.
+ */
+ else if (is_singlestep)
+ goto out;
+ }
+
+ if (!(current->ptrace & PT_PTRACED))
+ goto out;
+
+ /* If a process stops on the 1st tracepoint with SYSCALL_TRACE
+ * and then is resumed with SYSEMU_SINGLESTEP, it will come in
+ * here. We have to check this and return */
+ if (is_sysemu && entryexit)
+ return 0;
+
+ /* Fake a debug trap */
+ if (is_singlestep)
+ send_sigtrap(current, regs, 0);
+
+ if (!test_thread_flag(TIF_SYSCALL_TRACE) && !is_sysemu)
+ goto out;
+
+ /* the 0x80 provides a way for the tracing parent to distinguish
+ between a syscall stop and SIGTRAP delivery */
+ /* Note that the debugger could change the result of test_thread_flag!*/
+ ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) ? 0x80:0));
+
+ /*
+ * this isn't the same as continuing with a signal, but it will do
+ * for normal use. strace only continues with a signal if the
+ * stopping signal is not SIGTRAP. -brl
+ */
+ if (current->exit_code) {
+ send_sig(current->exit_code, current, 1);
+ current->exit_code = 0;
+ }
+ ret = is_sysemu;
+out:
+ if (unlikely(current->audit_context) && !entryexit)
+ audit_syscall_entry(AUDIT_ARCH_I386, regs->orig_eax,
+ regs->ebx, regs->ecx, regs->edx, regs->esi);
+ if (ret == 0)
+ return 0;
+
+ regs->orig_eax = -1; /* force skip of syscall restarting */
+ if (unlikely(current->audit_context))
+ audit_syscall_exit(AUDITSC_RESULT(regs->eax), regs->eax);
+ return 1;
+}
projects / openwrt / staging / blogic.git / commitdiff