Peter Zijlstra [Fri, 24 Apr 2020 14:18:58 +0000 (16:18 +0200)]
objtool: Remove INSN_STACK
With the unconditional use of handle_insn_ops(), INSN_STACK has lost
its purpose. Remove it.
Suggested-by: Julien Thierry <jthierry@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200428191659.854203028@infradead.org
Peter Zijlstra [Fri, 24 Apr 2020 14:16:41 +0000 (16:16 +0200)]
objtool: Make handle_insn_ops() unconditional
Now that every instruction has a list of stack_ops; we can trivially
distinquish those instructions that do not have stack_ops, their list
is empty.
This means we can now call handle_insn_ops() unconditionally.
Suggested-by: Julien Thierry <jthierry@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200428191659.795115188@infradead.org
Peter Zijlstra [Thu, 23 Apr 2020 11:22:10 +0000 (13:22 +0200)]
objtool: Rework allocating stack_ops on decode
Wrap each stack_op in a macro that allocates and adds it to the list.
This simplifies trying to figure out what to do with the pre-allocated
stack_op at the end.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200428191659.736151601@infradead.org
Alexandre Chartre [Tue, 7 Apr 2020 07:31:35 +0000 (09:31 +0200)]
objtool: UNWIND_HINT_RET_OFFSET should not check registers
UNWIND_HINT_RET_OFFSET will adjust a modified stack. However if a
callee-saved register was pushed on the stack then the stack frame
will still appear modified. So stop checking registers when
UNWIND_HINT_RET_OFFSET is used.
Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200407073142.20659-3-alexandre.chartre@oracle.com
Alexandre Chartre [Tue, 14 Apr 2020 10:36:10 +0000 (12:36 +0200)]
objtool: is_fentry_call() crashes if call has no destination
Fix is_fentry_call() so that it works if a call has no destination
set (call_dest). This needs to be done in order to support intra-
function calls.
Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200414103618.12657-2-alexandre.chartre@oracle.com
Peter Zijlstra [Tue, 28 Apr 2020 17:57:59 +0000 (19:57 +0200)]
x86,smap: Fix smap_{save,restore}() alternatives
As reported by objtool:
lib/ubsan.o: warning: objtool: .altinstr_replacement+0x0: alternative modifies stack
lib/ubsan.o: warning: objtool: .altinstr_replacement+0x7: alternative modifies stack
the smap_{save,restore}() alternatives violate (the newly enforced)
rule on stack invariance. That is, due to there only being a single
ORC table it must be valid to any alternative. These alternatives
violate this with the direct result that unwinds will not be correct
when it hits between the PUSH and POP instructions.
Rewrite the functions to only have a conditional jump.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200429101802.GI13592@hirez.programming.kicks-ass.net
Peter Zijlstra [Tue, 28 Apr 2020 17:37:01 +0000 (19:37 +0200)]
objtool: Fix ORC vs alternatives
Jann reported that (for instance) entry_64.o:general_protection has
very odd ORC data:
0000000000000f40 <general_protection>:
#######sp:sp+8 bp:(und) type:iret end:0
f40: 90 nop
#######sp:(und) bp:(und) type:call end:0
f41: 90 nop
f42: 90 nop
#######sp:sp+8 bp:(und) type:iret end:0
f43: e8 a8 01 00 00 callq 10f0 <error_entry>
#######sp:sp+0 bp:(und) type:regs end:0
f48: f6 84 24 88 00 00 00 testb $0x3,0x88(%rsp)
f4f: 03
f50: 74 00 je f52 <general_protection+0x12>
f52: 48 89 e7 mov %rsp,%rdi
f55: 48 8b 74 24 78 mov 0x78(%rsp),%rsi
f5a: 48 c7 44 24 78 ff ff movq $0xffffffffffffffff,0x78(%rsp)
f61: ff ff
f63: e8 00 00 00 00 callq f68 <general_protection+0x28>
f68: e9 73 02 00 00 jmpq 11e0 <error_exit>
#######sp:(und) bp:(und) type:call end:0
f6d: 0f 1f 00 nopl (%rax)
Note the entry at 0xf41. Josh found this was the result of commit:
764eef4b109a ("objtool: Rewrite alt->skip_orig")
Due to the early return in validate_branch() we no longer set
insn->cfi of the original instruction stream (the NOPs at 0xf41 and
0xf42) and we'll end up with the above weirdness.
In other discussions we realized alternatives should be ORC invariant;
that is, due to there being only a single ORC table, it must be valid
for all alternatives. The easiest way to ensure this is to not allow
any stack modifications in alternatives.
When we enforce this latter observation, we get the property that the
whole alternative must have the same CFI, which we can employ to fix
the former report.
Fixes: 764eef4b109a ("objtool: Rewrite alt->skip_orig")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200428191659.499074346@infradead.org
Alexandre Chartre [Tue, 14 Apr 2020 10:36:11 +0000 (12:36 +0200)]
objtool: Uniquely identify alternative instruction groups
Assign a unique identifier to every alternative instruction group in
order to be able to tell which instructions belong to what
alternative.
[peterz: extracted from a larger patch]
Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Julien Thierry [Fri, 27 Mar 2020 15:28:42 +0000 (15:28 +0000)]
objtool: Remove check preventing branches within alternative
While jumping from outside an alternative region to the middle of an
alternative region is very likely wrong, jumping from an alternative
region into the same region is valid. It is a common pattern on arm64.
The first pattern is unlikely to happen in practice and checking only
for this adds a lot of complexity.
Just remove the current check.
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/20200327152847.15294-6-jthierry@redhat.com
Ingo Molnar [Wed, 22 Apr 2020 10:32:05 +0000 (12:32 +0200)]
objtool: Constify arch_decode_instruction()
Mostly straightforward constification, except that WARN_FUNC()
needs a writable pointer while we have read-only pointers,
so deflect this to WARN().
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200422103205.61900-4-mingo@kernel.org
Ingo Molnar [Wed, 22 Apr 2020 10:32:04 +0000 (12:32 +0200)]
objtool: Rename elf_read() to elf_open_read()
'struct elf *' handling is an open/close paradigm, make sure the naming
matches that:
elf_open_read()
elf_write()
elf_close()
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200422103205.61900-3-mingo@kernel.org
Ingo Molnar [Wed, 22 Apr 2020 10:32:03 +0000 (12:32 +0200)]
objtool: Constify 'struct elf *' parameters
In preparation to parallelize certain parts of objtool, map out which uses
of various data structures are read-only vs. read-write.
As a first step constify 'struct elf' pointer passing, most of the secondary
uses of it in find_symbol_*() methods are read-only.
Also, while at it, better group the 'struct elf' handling methods in elf.h.
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200422103205.61900-2-mingo@kernel.org
Thomas Gleixner [Wed, 25 Mar 2020 16:18:17 +0000 (17:18 +0100)]
objtool: Also consider .entry.text as noinstr
Consider all of .entry.text as noinstr. This gets us coverage across
the PTI boundary. While we could add everything .noinstr.text into
.entry.text that would bloat the amount of code in the user mapping.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115119.525037514@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Mon, 23 Mar 2020 17:26:03 +0000 (18:26 +0100)]
objtool: Add STT_NOTYPE noinstr validation
Make sure to also check STT_NOTYPE symbols for noinstr violations.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115119.465335884@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Mon, 23 Mar 2020 20:17:50 +0000 (21:17 +0100)]
objtool: Rearrange validate_section()
In preparation of further changes, once again break out the loop body.
No functional changes intended.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115119.405863817@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Mon, 23 Mar 2020 20:11:14 +0000 (21:11 +0100)]
objtool: Avoid iterating !text section symbols
validate_functions() iterates all sections their symbols; this is
pointless to do for !text sections as they won't have instructions
anyway.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115119.346582716@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Wed, 18 Mar 2020 12:33:54 +0000 (13:33 +0100)]
kbuild/objtool: Add objtool-vmlinux.o pass
Now that objtool is capable of processing vmlinux.o and actually has
something useful to do there, (conditionally) add it to the final link
pass.
This will increase build time by a few seconds.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115119.287494491@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Mon, 16 Mar 2020 14:47:27 +0000 (15:47 +0100)]
objtool: Use sec_offset_hash() for insn_hash
In preparation for find_insn_containing(), change insn_hash to use
sec_offset_hash().
This actually reduces runtime; probably because mixing in the section
index reduces the collisions due to text sections all starting their
instructions at offset 0.
Runtime on vmlinux.o from 3.1 to 2.5 seconds.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115119.227240432@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Thu, 12 Mar 2020 13:29:38 +0000 (14:29 +0100)]
objtool: Optimize !vmlinux.o again
When doing kbuild tests to see if the objtool changes affected those I
found that there was a measurable regression:
pre post
real 1m13.594 1m16.488s
user 34m58.246s 35m23.947s
sys 4m0.393s 4m27.312s
Perf showed that for small files the increased hash-table sizes were a
measurable difference. Since we already have -l "vmlinux" to
distinguish between the modes, make it also use a smaller portion of
the hash-tables.
This flips it into a small win:
real 1m14.143s
user 34m49.292s
sys 3m44.746s
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115119.167588731@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Tue, 10 Mar 2020 17:57:41 +0000 (18:57 +0100)]
objtool: Implement noinstr validation
Validate that any call out of .noinstr.text is in between
instr_begin() and instr_end() annotations.
This annotation is useful to ensure correct behaviour wrt tracing
sensitive code like entry/exit and idle code. When we run code in a
sensitive context we want a guarantee no unknown code is ran.
Since this validation relies on knowing the section of call
destination symbols, we must run it on vmlinux.o instead of on
individual object files.
Add two options:
-d/--duplicate "duplicate validation for vmlinux"
-l/--vmlinux "vmlinux.o validation"
Where the latter auto-detects when objname ends with "vmlinux.o" and
the former will force all validations, also those already done on
!vmlinux object files.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115119.106268040@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Wed, 25 Mar 2020 13:04:45 +0000 (14:04 +0100)]
objtool: Fix !CFI insn_state propagation
Objtool keeps per instruction CFI state in struct insn_state and will
save/restore this where required. However, insn_state has grown some
!CFI state, and this must not be saved/restored (that would
loose/destroy state).
Fix this by moving the CFI specific parts of insn_state into struct
cfi_state.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115119.045821071@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Wed, 25 Mar 2020 14:34:50 +0000 (15:34 +0100)]
objtool: Rename struct cfi_state
There's going to be a new struct cfi_state, rename this one to make
place.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115118.986441913@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Wed, 1 Apr 2020 14:54:26 +0000 (16:54 +0200)]
objtool: Remove SAVE/RESTORE hints
The SAVE/RESTORE hints are now unused; remove them.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115118.926738768@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Wed, 1 Apr 2020 14:51:11 +0000 (16:51 +0200)]
x86,ftrace: Shrink ftrace_regs_caller() by one byte
'Optimize' ftrace_regs_caller. Instead of comparing against an
immediate, the more natural way to test for zero on x86 is: 'test
%r,%r'.
48 83 f8 00 cmp $0x0,%rax
74 49 je 226 <ftrace_regs_call+0xa3>
48 85 c0 test %rax,%rax
74 49 je 225 <ftrace_regs_call+0xa2>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115118.867411350@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Wed, 1 Apr 2020 14:50:40 +0000 (16:50 +0200)]
x86,ftrace: Use SIZEOF_PTREGS
There's a convenient macro for 'SS+8' called FRAME_SIZE. Use it to
clarify things.
(entry/calling.h calls this SIZEOF_PTREGS but we're using
asm/ptrace-abi.h)
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115118.808485515@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Wed, 1 Apr 2020 14:53:19 +0000 (16:53 +0200)]
x86,ftrace: Fix ftrace_regs_caller() unwind
The ftrace_regs_caller() trampoline does something 'funny' when there
is a direct-caller present. In that case it stuffs the 'direct-caller'
address on the return stack and then exits the function. This then
results in 'returning' to the direct-caller with the exact registers
we came in with -- an indirect tail-call without using a register.
This however (rightfully) confuses objtool because the function shares
a few instruction in order to have a single exit path, but the stack
layout is different for them, depending through which path we came
there.
This is currently cludged by forcing the stack state to the non-direct
case, but this generates actively wrong (ORC) unwind information for
the direct case, leading to potential broken unwinds.
Fix this issue by fully separating the exit paths. This results in
having to poke a second RET into the trampoline copy, see
ftrace_regs_caller_ret.
This brings us to a second objtool problem, in order for it to
perceive the 'jmp ftrace_epilogue' as a function exit, it needs to be
recognised as a tail call. In order to make that happen,
ftrace_epilogue needs to be the start of an STT_FUNC, so re-arrange
code to make this so.
Finally, a third issue is that objtool requires functions to exit with
the same stack layout they started with, which is obviously violated
in the direct case, employ the new HINT_RET_OFFSET to tell objtool
this is an expected exception.
Together, this results in generating correct ORC unwind information
for the ftrace_regs_caller() function and it's trampoline copies.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115118.749606694@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Wed, 1 Apr 2020 14:38:19 +0000 (16:38 +0200)]
objtool: Introduce HINT_RET_OFFSET
Normally objtool ensures a function keeps the stack layout invariant.
But there is a useful exception, it is possible to stuff the return
stack in order to 'inject' a 'call':
push $fun
ret
In this case the invariant mentioned above is violated.
Add an objtool HINT to annotate this and allow a function exit with a
modified stack frame.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115118.690601403@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Thu, 2 Apr 2020 08:15:51 +0000 (10:15 +0200)]
objtool: Better handle IRET
Teach objtool a little more about IRET so that we can avoid using the
SAVE/RESTORE annotation. In particular, make the weird corner case in
insn->restore go away.
The purpose of that corner case is to deal with the fact that
UNWIND_HINT_RESTORE lands on the instruction after IRET, but that
instruction can end up being outside the basic block, consider:
if (cond)
sync_core()
foo();
Then the hint will land on foo(), and we'll encounter the restore
hint without ever having seen the save hint.
By teaching objtool about the arch specific exception frame size, and
assuming that any IRET in an STT_FUNC symbol is an exception frame
sized POP, we can remove the use of save/restore hints for this code.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115118.631224674@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Julien Thierry [Fri, 27 Mar 2020 15:28:47 +0000 (15:28 +0000)]
objtool: Support multiple stack_op per instruction
Instruction sets can include more or less complex operations which might
not fit the currently defined set of stack_ops.
Combining more than one stack_op provides more flexibility to describe
the behaviour of an instruction. This also reduces the need to define
new stack_ops specific to a single instruction set.
Allow instruction decoders to generate multiple stack_op per
instruction.
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200327152847.15294-11-jthierry@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Muchun Song [Sun, 12 Apr 2020 14:44:05 +0000 (22:44 +0800)]
objtool: Remove redundant .rodata section name comparison
If the prefix of section name is not '.rodata', the following
function call can never return 0.
strcmp(sec->name, C_JUMP_TABLE_SECTION)
So the name comparison is pointless, just remove it.
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Nick Desaulniers [Thu, 26 Mar 2020 18:37:06 +0000 (11:37 -0700)]
objtool: Documentation: document UACCESS warnings
Compiling with Clang and CONFIG_KASAN=y was exposing a few warnings:
call to memset() with UACCESS enabled
Document how to fix these for future travelers.
Link: https://github.com/ClangBuiltLinux/linux/issues/876
Suggested-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Suggested-by: Matt Helsley <mhelsley@vmware.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Suggested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Julien Thierry [Fri, 27 Mar 2020 15:28:46 +0000 (15:28 +0000)]
objtool: Split out arch-specific CFI definitions
Some CFI definitions used by generic objtool code have no reason to vary
from one architecture to another. Keep those definitions in generic
code and move the arch-specific ones to a new arch-specific header.
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Raphael Gault [Fri, 27 Mar 2020 15:28:45 +0000 (15:28 +0000)]
objtool: Add abstraction for destination offsets
The jump and call destination relocation offsets are x86-specific.
Abstract them by calling arch-specific implementations.
[ jthierry: Remove superfluous comment; replace other addend offsets
with arch_dest_rela_offset() ]
Signed-off-by: Raphael Gault <raphael.gault@arm.com>
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Julien Thierry [Fri, 27 Mar 2020 15:28:43 +0000 (15:28 +0000)]
objtool: Use arch specific values in restore_reg()
The initial register state is set up by arch specific code. Use the
value the arch code has set when restoring registers from the stack.
Suggested-by: Raphael Gault <raphael.gault@arm.com>
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Julien Thierry [Fri, 27 Mar 2020 15:28:41 +0000 (15:28 +0000)]
objtool: Ignore empty alternatives
The .alternatives section can contain entries with no original
instructions. Objtool will currently crash when handling such an entry.
Just skip that entry, but still give a warning to discourage useless
entries.
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Julien Thierry [Fri, 27 Mar 2020 15:28:40 +0000 (15:28 +0000)]
objtool: Clean instruction state before each function validation
When a function fails its validation, it might leave a stale state
that will be used for the validation of other functions. That would
cause false warnings on potentially valid functions.
Reset the instruction state before the validation of each individual
function.
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Julien Thierry [Fri, 27 Mar 2020 15:28:39 +0000 (15:28 +0000)]
objtool: Remove redundant checks on operand type
POP operations are already in the code path where the destination
operand is OP_DEST_REG. There is no need to check the operand type
again.
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Julien Thierry [Fri, 27 Mar 2020 15:28:38 +0000 (15:28 +0000)]
objtool: Always do header sync check
Currently, the check of tools files against kernel equivalent is only
done after every object file has been built. This means one might fix
build issues against outdated headers without seeing a warning about
this.
Check headers before any object is built. Also, make it part of a
FORCE'd recipe so every attempt to build objtool will report the
outdated headers (if any).
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Julien Thierry [Fri, 3 Apr 2020 13:17:30 +0000 (14:17 +0100)]
objtool: Fix off-by-one in symbol_by_offset()
Sometimes, WARN_FUNC() and other users of symbol_by_offset() will
associate the first instruction of a symbol with the symbol preceding
it. This is because symbol->offset + symbol->len is already outside of
the symbol's range.
Fixes: 2a362ecc3ec9 ("objtool: Optimize find_symbol_*() and read_symbols()")
Signed-off-by: Julien Thierry <jthierry@redhat.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra [Mon, 20 Apr 2020 08:33:32 +0000 (10:33 +0200)]
objtool: Fix 32bit cross builds
Apparently there's people doing 64bit builds on 32bit machines.
Fixes: 74b873e49d92 ("objtool: Optimize find_rela_by_dest_range()")
Reported-by: youling257@gmail.com
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Linus Torvalds [Tue, 21 Apr 2020 20:26:54 +0000 (13:26 -0700)]
Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
"15 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
tools/vm: fix cross-compile build
coredump: fix null pointer dereference on coredump
mm: shmem: disable interrupt when acquiring info->lock in userfaultfd_copy path
shmem: fix possible deadlocks on shmlock_user_lock
vmalloc: fix remap_vmalloc_range() bounds checks
mm/shmem: fix build without THP
mm/ksm: fix NULL pointer dereference when KSM zero page is enabled
tools/build: tweak unused value workaround
checkpatch: fix a typo in the regex for $allocFunctions
mm, gup: return EINTR when gup is interrupted by fatal signals
mm/hugetlb: fix a addressing exception caused by huge_pte_offset
MAINTAINERS: add an entry for kfifo
mm/userfaultfd: disable userfaultfd-wp on x86_32
slub: avoid redzone when choosing freepointer location
sh: fix build error in mm/init.c
Linus Torvalds [Tue, 21 Apr 2020 19:59:10 +0000 (12:59 -0700)]
Merge tag 'for-linus' of git://git./virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"Bugfixes, and a few cleanups to the newly-introduced assembly language
vmentry code for AMD"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: PPC: Book3S HV: Handle non-present PTEs in page fault functions
kvm: Disable objtool frame pointer checking for vmenter.S
MAINTAINERS: add a reviewer for KVM/s390
KVM: s390: Fix PV check in deliverable_irqs()
kvm: Handle reads of SandyBridge RAPL PMU MSRs rather than injecting #GP
KVM: Remove CREATE_IRQCHIP/SET_PIT2 race
KVM: SVM: Fix __svm_vcpu_run declaration.
KVM: SVM: Do not setup frame pointer in __svm_vcpu_run
KVM: SVM: Fix build error due to missing release_pages() include
KVM: SVM: Do not mark svm_vcpu_run with STACK_FRAME_NON_STANDARD
kvm: nVMX: match comment with return type for nested_vmx_exit_reflected
kvm: nVMX: reflect MTF VM-exits if injected by L1
KVM: s390: Return last valid slot if approx index is out-of-bounds
KVM: Check validity of resolved slot when searching memslots
KVM: VMX: Enable machine check support for 32bit targets
KVM: SVM: move more vmentry code to assembly
KVM: SVM: fix compilation with modular PSP and non-modular KVM
Linus Torvalds [Tue, 21 Apr 2020 19:27:18 +0000 (12:27 -0700)]
Merge tag 'for_linus' of git://git./linux/kernel/git/mst/vhost
Pull virtio fixes and cleanups from Michael Tsirkin:
- Some bug fixes
- Cleanup a couple of issues that surfaced meanwhile
- Disable vhost on ARM with OABI for now - to be fixed fully later in
the cycle or in the next release.
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (24 commits)
vhost: disable for OABI
virtio: drop vringh.h dependency
virtio_blk: add a missing include
virtio-balloon: Avoid using the word 'report' when referring to free page hinting
virtio-balloon: make virtballoon_free_page_report() static
vdpa: fix comment of vdpa_register_device()
vdpa: make vhost, virtio depend on menu
vdpa: allow a 32 bit vq alignment
drm/virtio: fix up for include file changes
remoteproc: pull in slab.h
rpmsg: pull in slab.h
virtio_input: pull in slab.h
remoteproc: pull in slab.h
virtio-rng: pull in slab.h
virtgpu: pull in uaccess.h
tools/virtio: make asm/barrier.h self contained
tools/virtio: define aligned attribute
virtio/test: fix up after IOTLB changes
vhost: Create accessors for virtqueues private_data
vdpasim: Return status in vdpasim_get_status
...
Linus Torvalds [Tue, 21 Apr 2020 19:24:33 +0000 (12:24 -0700)]
Merge tag 'tpmdd-next-
20200421' of git://git.infradead.org/users/jjs/linux-tpmdd
Pull tpm fixes from Jarkko Sakkinen:
"A few bug fixes"
* tag 'tpmdd-next-
20200421' of git://git.infradead.org/users/jjs/linux-tpmdd:
tpm/tpm_tis: Free IRQ if probing fails
tpm: fix wrong return value in tpm_pcr_extend
tpm: ibmvtpm: retry on H_CLOSED in tpm_ibmvtpm_send()
tpm: Export tpm2_get_cc_attrs_tbl for ibmvtpm driver as module
Linus Torvalds [Tue, 21 Apr 2020 19:07:42 +0000 (12:07 -0700)]
Merge tag 'clang-format-for-linus-v5.7-rc3' of git://github.com/ojeda/linux
Pull clang-format fixlets from Miguel Ojeda:
"Two trivial clang-format changes:
- Don't indent C++ namespaces (Ian Rogers)
- The usual clang-format macro list update (Miguel Ojeda)"
* tag 'clang-format-for-linus-v5.7-rc3' of git://github.com/ojeda/linux:
clang-format: Update with the latest for_each macro list
clang-format: don't indent namespaces
Lucas Stach [Tue, 21 Apr 2020 01:14:23 +0000 (18:14 -0700)]
tools/vm: fix cross-compile build
Commit
7ed1c1901fe5 ("tools: fix cross-compile var clobbering") moved
the setup of the CC variable to tools/scripts/Makefile.include to make
the behavior consistent across all the tools Makefiles.
As the vm tools missed the include we end up with the wrong CC in a
cross-compiling evironment.
Fixes: 7ed1c1901fe5 (tools: fix cross-compile var clobbering)
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Martin Kelly <martin@martingkelly.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200416104748.25243-1-l.stach@pengutronix.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sudip Mukherjee [Tue, 21 Apr 2020 01:14:20 +0000 (18:14 -0700)]
coredump: fix null pointer dereference on coredump
If the core_pattern is set to "|" and any process segfaults then we get
a null pointer derefernce while trying to coredump. The call stack shows:
RIP: do_coredump+0x628/0x11c0
When the core_pattern has only "|" there is no use of trying the
coredump and we can check that while formating the corename and exit
with an error.
After this change I get:
format_corename failed
Aborting core
Fixes: 315c69261dd3 ("coredump: split pipe command whitespace before expanding template")
Reported-by: Matthew Ruffell <matthew.ruffell@canonical.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Wise <pabs3@bonedaddy.net>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200416194612.21418-1-sudipm.mukherjee@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yang Shi [Tue, 21 Apr 2020 01:14:17 +0000 (18:14 -0700)]
mm: shmem: disable interrupt when acquiring info->lock in userfaultfd_copy path
Syzbot reported the below lockdep splat:
WARNING: possible irq lock inversion dependency detected
5.6.0-rc7-syzkaller #0 Not tainted
--------------------------------------------------------
syz-executor.0/10317 just changed the state of lock:
ffff888021d16568 (&(&info->lock)->rlock){+.+.}, at: spin_lock include/linux/spinlock.h:338 [inline]
ffff888021d16568 (&(&info->lock)->rlock){+.+.}, at: shmem_mfill_atomic_pte+0x1012/0x21c0 mm/shmem.c:2407
but this lock was taken by another, SOFTIRQ-safe lock in the past:
(&(&xa->xa_lock)->rlock#5){..-.}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&(&info->lock)->rlock);
local_irq_disable();
lock(&(&xa->xa_lock)->rlock#5);
lock(&(&info->lock)->rlock);
<Interrupt>
lock(&(&xa->xa_lock)->rlock#5);
*** DEADLOCK ***
The full report is quite lengthy, please see:
https://lore.kernel.org/linux-mm/alpine.LSU.2.11.
2004152007370.13597@eggly.anvils/T/#m813b412c5f78e25ca8c6c7734886ed4de43f241d
It is because CPU 0 held info->lock with IRQ enabled in userfaultfd_copy
path, then CPU 1 is splitting a THP which held xa_lock and info->lock in
IRQ disabled context at the same time. If softirq comes in to acquire
xa_lock, the deadlock would be triggered.
The fix is to acquire/release info->lock with *_irq version instead of
plain spin_{lock,unlock} to make it softirq safe.
Fixes: 4c27fe4c4c84 ("userfaultfd: shmem: add shmem_mcopy_atomic_pte for userfaultfd support")
Reported-by: syzbot+e27980339d305f2dbfd9@syzkaller.appspotmail.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: syzbot+e27980339d305f2dbfd9@syzkaller.appspotmail.com
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Link: http://lkml.kernel.org/r/1587061357-122619-1-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Tue, 21 Apr 2020 01:14:14 +0000 (18:14 -0700)]
shmem: fix possible deadlocks on shmlock_user_lock
Recent commit
71725ed10c40 ("mm: huge tmpfs: try to split_huge_page()
when punching hole") has allowed syzkaller to probe deeper, uncovering a
long-standing lockdep issue between the irq-unsafe shmlock_user_lock,
the irq-safe xa_lock on mapping->i_pages, and shmem inode's info->lock
which nests inside xa_lock (or tree_lock) since 4.8's shmem_uncharge().
user_shm_lock(), servicing SysV shmctl(SHM_LOCK), wants
shmlock_user_lock while its caller shmem_lock() holds info->lock with
interrupts disabled; but hugetlbfs_file_setup() calls user_shm_lock()
with interrupts enabled, and might be interrupted by a writeback endio
wanting xa_lock on i_pages.
This may not risk an actual deadlock, since shmem inodes do not take
part in writeback accounting, but there are several easy ways to avoid
it.
Requiring interrupts disabled for shmlock_user_lock would be easy, but
it's a high-level global lock for which that seems inappropriate.
Instead, recall that the use of info->lock to guard info->flags in
shmem_lock() dates from pre-3.1 days, when races with SHMEM_PAGEIN and
SHMEM_TRUNCATE could occur: nowadays it serves no purpose, the only flag
added or removed is VM_LOCKED itself, and calls to shmem_lock() an inode
are already serialized by the caller.
Take info->lock out of the chain and the possibility of deadlock or
lockdep warning goes away.
Fixes: 4595ef88d136 ("shmem: make shmem_inode_info::lock irq-safe")
Reported-by: syzbot+c8a8197c8852f566b9d9@syzkaller.appspotmail.com
Reported-by: syzbot+40b71e145e73f78f81ad@syzkaller.appspotmail.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2004161707410.16322@eggly.anvils
Link: https://lore.kernel.org/lkml/000000000000e5838c05a3152f53@google.com/
Link: https://lore.kernel.org/lkml/0000000000003712b305a331d3b1@google.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jann Horn [Tue, 21 Apr 2020 01:14:11 +0000 (18:14 -0700)]
vmalloc: fix remap_vmalloc_range() bounds checks
remap_vmalloc_range() has had various issues with the bounds checks it
promises to perform ("This function checks that addr is a valid
vmalloc'ed area, and that it is big enough to cover the vma") over time,
e.g.:
- not detecting pgoff<<PAGE_SHIFT overflow
- not detecting (pgoff<<PAGE_SHIFT)+usize overflow
- not checking whether addr and addr+(pgoff<<PAGE_SHIFT) are the same
vmalloc allocation
- comparing a potentially wildly out-of-bounds pointer with the end of
the vmalloc region
In particular, since commit
fc9702273e2e ("bpf: Add mmap() support for
BPF_MAP_TYPE_ARRAY"), unprivileged users can cause kernel null pointer
dereferences by calling mmap() on a BPF map with a size that is bigger
than the distance from the start of the BPF map to the end of the
address space.
This could theoretically be used as a kernel ASLR bypass, by using
whether mmap() with a given offset oopses or returns an error code to
perform a binary search over the possible address range.
To allow remap_vmalloc_range_partial() to verify that addr and
addr+(pgoff<<PAGE_SHIFT) are in the same vmalloc region, pass the offset
to remap_vmalloc_range_partial() instead of adding it to the pointer in
remap_vmalloc_range().
In remap_vmalloc_range_partial(), fix the check against
get_vm_area_size() by using size comparisons instead of pointer
comparisons, and add checks for pgoff.
Fixes: 833423143c3a ("[PATCH] mm: introduce remap_vmalloc_range()")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@chromium.org>
Link: http://lkml.kernel.org/r/20200415222312.236431-1-jannh@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hugh Dickins [Tue, 21 Apr 2020 01:14:07 +0000 (18:14 -0700)]
mm/shmem: fix build without THP
Some optimizers don't notice that shmem_punch_compound() is always true
(PageTransCompound() being false) without CONFIG_TRANSPARENT_HUGEPAGE==y.
Use IS_ENABLED to help them to avoid the BUILD_BUG inside HPAGE_PMD_NR.
Fixes: 71725ed10c40 ("mm: huge tmpfs: try to split_huge_page() when punching hole")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2004142339170.10035@eggly.anvils
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Muchun Song [Tue, 21 Apr 2020 01:14:04 +0000 (18:14 -0700)]
mm/ksm: fix NULL pointer dereference when KSM zero page is enabled
find_mergeable_vma() can return NULL. In this case, it leads to a crash
when we access vm_mm(its offset is 0x40) later in write_protect_page.
And this case did happen on our server. The following call trace is
captured in kernel 4.19 with the following patch applied and KSM zero
page enabled on our server.
commit
e86c59b1b12d ("mm/ksm: improve deduplication of zero pages with colouring")
So add a vma check to fix it.
BUG: unable to handle kernel NULL pointer dereference at
0000000000000040
Oops: 0000 [#1] SMP NOPTI
CPU: 9 PID: 510 Comm: ksmd Kdump: loaded Tainted: G OE 4.19.36.bsk.9-amd64 #4.19.36.bsk.9
RIP: try_to_merge_one_page+0xc7/0x760
Code: 24 58 65 48 33 34 25 28 00 00 00 89 e8 0f 85 a3 06 00 00 48 83 c4
60 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 8b 46 08 a8 01 75 b8 <49>
8b 44 24 40 4c 8d 7c 24 20 b9 07 00 00 00 4c 89 e6 4c 89 ff 48
RSP: 0018:
ffffadbdd9fffdb0 EFLAGS:
00010246
RAX:
ffffda83ffd4be08 RBX:
ffffda83ffd4be40 RCX:
0000002c6e800000
RDX:
0000000000000000 RSI:
ffffda83ffd4be40 RDI:
0000000000000000
RBP:
ffffa11939f02ec0 R08:
0000000094e1a447 R09:
00000000abe76577
R10:
0000000000000962 R11:
0000000000004e6a R12:
0000000000000000
R13:
ffffda83b1e06380 R14:
ffffa18f31f072c0 R15:
ffffda83ffd4be40
FS:
0000000000000000(0000) GS:
ffffa0da43b80000(0000) knlGS:
0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0:
0000000080050033
CR2:
0000000000000040 CR3:
0000002c77c0a003 CR4:
00000000007626e0
DR0:
0000000000000000 DR1:
0000000000000000 DR2:
0000000000000000
DR3:
0000000000000000 DR6:
00000000fffe0ff0 DR7:
0000000000000400
PKRU:
55555554
Call Trace:
ksm_scan_thread+0x115e/0x1960
kthread+0xf5/0x130
ret_from_fork+0x1f/0x30
[songmuchun@bytedance.com: if the vma is out of date, just exit]
Link: http://lkml.kernel.org/r/20200416025034.29780-1-songmuchun@bytedance.com
[akpm@linux-foundation.org: add the conventional braces, replace /** with /*]
Fixes: e86c59b1b12d ("mm/ksm: improve deduplication of zero pages with colouring")
Co-developed-by: Xiongchun Duan <duanxiongchun@bytedance.com>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Cc: Markus Elfring <Markus.Elfring@web.de>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200416025034.29780-1-songmuchun@bytedance.com
Link: http://lkml.kernel.org/r/20200414132905.83819-1-songmuchun@bytedance.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
George Burgess IV [Tue, 21 Apr 2020 01:14:01 +0000 (18:14 -0700)]
tools/build: tweak unused value workaround
Clang has -Wself-assign enabled by default under -Wall, which always
gets -Werror'ed on this file, causing sync-compare-and-swap to be
disabled by default.
The generally-accepted way to spell "this value is intentionally
unused," is casting it to `void`. This is accepted by both GCC and
Clang with -Wall enabled: https://godbolt.org/z/qqZ9r3
Signed-off-by: George Burgess IV <gbiv@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Link: http://lkml.kernel.org/r/20200414195638.156123-1-gbiv@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christophe JAILLET [Tue, 21 Apr 2020 01:13:58 +0000 (18:13 -0700)]
checkpatch: fix a typo in the regex for $allocFunctions
Here, we look for function such as 'netdev_alloc_skb_ip_align', so a '_'
is missing in the regex.
To make sure:
grep -r --include=*.c skbip_a * | wc ==> 0 results
grep -r --include=*.c skb_ip_a * | wc ==> 112 results
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joe Perches <joe@perches.com>
Link: http://lkml.kernel.org/r/20200407190029.892-1-christophe.jaillet@wanadoo.fr
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Tue, 21 Apr 2020 01:13:55 +0000 (18:13 -0700)]
mm, gup: return EINTR when gup is interrupted by fatal signals
EINTR is the usual error code which other killable interfaces return.
This is the case for the other fatal_signal_pending break out from the
same function. Make the code consistent.
ERESTARTSYS is also quite confusing because the signal is fatal and so
no restart will happen before returning to the userspace.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: http://lkml.kernel.org/r/20200409071133.31734-1-mhocko@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Longpeng [Tue, 21 Apr 2020 01:13:51 +0000 (18:13 -0700)]
mm/hugetlb: fix a addressing exception caused by huge_pte_offset
Our machine encountered a panic(addressing exception) after run for a
long time and the calltrace is:
RIP: hugetlb_fault+0x307/0xbe0
RSP: 0018:
ffff9567fc27f808 EFLAGS:
00010286
RAX:
e800c03ff1258d48 RBX:
ffffd3bb003b69c0 RCX:
e800c03ff1258d48
RDX:
17ff3fc00eda72b7 RSI:
00003ffffffff000 RDI:
e800c03ff1258d48
RBP:
ffff9567fc27f8c8 R08:
e800c03ff1258d48 R09:
0000000000000080
R10:
ffffaba0704c22a8 R11:
0000000000000001 R12:
ffff95c87b4b60d8
R13:
00005fff00000000 R14:
0000000000000000 R15:
ffff9567face8074
FS:
00007fe2d9ffb700(0000) GS:
ffff956900e40000(0000) knlGS:
0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0:
0000000080050033
CR2:
ffffd3bb003b69c0 CR3:
000000be67374000 CR4:
00000000003627e0
DR0:
0000000000000000 DR1:
0000000000000000 DR2:
0000000000000000
DR3:
0000000000000000 DR6:
00000000fffe0ff0 DR7:
0000000000000400
Call Trace:
follow_hugetlb_page+0x175/0x540
__get_user_pages+0x2a0/0x7e0
__get_user_pages_unlocked+0x15d/0x210
__gfn_to_pfn_memslot+0x3c5/0x460 [kvm]
try_async_pf+0x6e/0x2a0 [kvm]
tdp_page_fault+0x151/0x2d0 [kvm]
...
kvm_arch_vcpu_ioctl_run+0x330/0x490 [kvm]
kvm_vcpu_ioctl+0x309/0x6d0 [kvm]
do_vfs_ioctl+0x3f0/0x540
SyS_ioctl+0xa1/0xc0
system_call_fastpath+0x22/0x27
For 1G hugepages, huge_pte_offset() wants to return NULL or pudp, but it
may return a wrong 'pmdp' if there is a race. Please look at the
following code snippet:
...
pud = pud_offset(p4d, addr);
if (sz != PUD_SIZE && pud_none(*pud))
return NULL;
/* hugepage or swap? */
if (pud_huge(*pud) || !pud_present(*pud))
return (pte_t *)pud;
pmd = pmd_offset(pud, addr);
if (sz != PMD_SIZE && pmd_none(*pmd))
return NULL;
/* hugepage or swap? */
if (pmd_huge(*pmd) || !pmd_present(*pmd))
return (pte_t *)pmd;
...
The following sequence would trigger this bug:
- CPU0: sz = PUD_SIZE and *pud = 0 , continue
- CPU0: "pud_huge(*pud)" is false
- CPU1: calling hugetlb_no_page and set *pud to xxxx8e7(PRESENT)
- CPU0: "!pud_present(*pud)" is false, continue
- CPU0: pmd = pmd_offset(pud, addr) and maybe return a wrong pmdp
However, we want CPU0 to return NULL or pudp in this case.
We must make sure there is exactly one dereference of pud and pmd.
Signed-off-by: Longpeng <longpeng2@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200413010342.771-1-longpeng2@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bartosz Golaszewski [Tue, 21 Apr 2020 01:13:48 +0000 (18:13 -0700)]
MAINTAINERS: add an entry for kfifo
Kfifo has been written by Stefani Seibold and she's implicitly expected
to Ack any changes to it. She's not however officially listed as kfifo
maintainer which leads to delays in patch review. This patch proposes
to add an explitic entry for kfifo to MAINTAINERS file.
[akpm@linux-foundation.org: alphasort F: entries, per Joe]
[akpm@linux-foundation.org: remove colon, per Bartosz]
Link: http://lkml.kernel.org/r/20200124174533.21815-1-brgl@bgdev.pl
Link: http://lkml.kernel.org/r/20200413104250.26683-1-brgl@bgdev.pl
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Peter Xu [Tue, 21 Apr 2020 01:13:45 +0000 (18:13 -0700)]
mm/userfaultfd: disable userfaultfd-wp on x86_32
Userfaultfd-wp is not yet working on 32bit hosts, but it's accidentally
enabled previously. Disable it.
Fixes: 5a281062af1d ("userfaultfd: wp: add WP pagetable tracking to x86")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: http://lkml.kernel.org/r/20200413141608.109211-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kees Cook [Tue, 21 Apr 2020 01:13:42 +0000 (18:13 -0700)]
slub: avoid redzone when choosing freepointer location
Marco Elver reported system crashes when booting with "slub_debug=Z".
The freepointer location (s->offset) was not taking into account that
the "inuse" size that includes the redzone area should not be used by
the freelist pointer. Change the calculation to save the area of the
object that an inline freepointer may be written into.
Fixes: 3202fa62fb43 ("slub: relocate freelist pointer to middle of object")
Reported-by: Marco Elver <elver@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Marco Elver <elver@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Link: http://lkml.kernel.org/r/202004151054.BD695840@keescook
Link: https://lore.kernel.org/linux-mm/20200415164726.GA234932@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Masahiro Yamada [Tue, 21 Apr 2020 01:13:38 +0000 (18:13 -0700)]
sh: fix build error in mm/init.c
The closing parenthesis is missing.
Fixes: bfeb022f8fe4 ("mm/memory_hotplug: add pgprot_t to mhp_params")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Link: http://lkml.kernel.org/r/20200413014743.16353-1-masahiroy@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Paolo Bonzini [Tue, 21 Apr 2020 13:39:55 +0000 (09:39 -0400)]
Merge tag 'kvm-ppc-fixes-5.7-1' of git://git./linux/kernel/git/paulus/powerpc into kvm-master
PPC KVM fix for 5.7
- Fix a regression introduced in the last merge window, which results
in guests in HPT mode dying randomly.
Paolo Bonzini [Tue, 21 Apr 2020 13:37:13 +0000 (09:37 -0400)]
Merge tag 'kvm-s390-master-5.7-2' of git://git./linux/kernel/git/kvms390/linux into kvm-master
KVM: s390: Fix for 5.7 and maintainer update
- Silence false positive lockdep warning
- add Claudio as reviewer
Paul Mackerras [Thu, 16 Apr 2020 04:23:43 +0000 (14:23 +1000)]
KVM: PPC: Book3S HV: Handle non-present PTEs in page fault functions
Since
cd758a9b57ee "KVM: PPC: Book3S HV: Use __gfn_to_pfn_memslot in HPT
page fault handler", it's been possible in fairly rare circumstances to
load a non-present PTE in kvmppc_book3s_hv_page_fault() when running a
guest on a POWER8 host.
Because that case wasn't checked for, we could misinterpret the non-present
PTE as being a cache-inhibited PTE. That could mismatch with the
corresponding hash PTE, which would cause the function to fail with -EFAULT
a little further down. That would propagate up to the KVM_RUN ioctl()
generally causing the KVM userspace (usually qemu) to fall over.
This addresses the problem by catching that case and returning to the guest
instead.
For completeness, this fixes the radix page fault handler in the same
way. For radix this didn't cause any obvious misbehaviour, because we
ended up putting the non-present PTE into the guest's partition-scoped
page tables, leading immediately to another hypervisor data/instruction
storage interrupt, which would go through the page fault path again
and fix things up.
Fixes: cd758a9b57ee "KVM: PPC: Book3S HV: Use __gfn_to_pfn_memslot in HPT page fault handler"
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=
1820402
Reported-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Josh Poimboeuf [Mon, 20 Apr 2020 16:17:37 +0000 (11:17 -0500)]
kvm: Disable objtool frame pointer checking for vmenter.S
Frame pointers are completely broken by vmenter.S because it clobbers
RBP:
arch/x86/kvm/svm/vmenter.o: warning: objtool: __svm_vcpu_run()+0xe4: BP used as a scratch register
That's unavoidable, so just skip checking that file when frame pointers
are configured in.
On the other hand, ORC can handle that code just fine, so leave objtool
enabled in the !FRAME_POINTER case.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Message-Id: <
01fae42917bacad18be8d2cbc771353da6603473.
1587398610.git.jpoimboe@redhat.com>
Tested-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Fixes: 199cd1d7b534 ("KVM: SVM: Split svm_vcpu_run inline assembly to separate file")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Jarkko Sakkinen [Sun, 12 Apr 2020 17:04:12 +0000 (20:04 +0300)]
tpm/tpm_tis: Free IRQ if probing fails
Call disable_interrupts() if we have to revert to polling in order not to
unnecessarily reserve the IRQ for the life-cycle of the driver.
Cc: stable@vger.kernel.org # 4.5.x
Reported-by: Hans de Goede <hdegoede@redhat.com>
Fixes: e3837e74a06d ("tpm_tis: Refactor the interrupt setup")
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tianjia Zhang [Tue, 14 Apr 2020 11:42:26 +0000 (19:42 +0800)]
tpm: fix wrong return value in tpm_pcr_extend
For the algorithm that does not match the bank, a positive
value EINVAL is returned here. I think this is a typo error.
It is necessary to return an error value.
Cc: stable@vger.kernel.org # 5.4.x
Fixes: 9f75c8224631 ("KEYS: trusted: correctly initialize digests and fix locking issue")
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
George Wilson [Fri, 20 Mar 2020 03:27:58 +0000 (23:27 -0400)]
tpm: ibmvtpm: retry on H_CLOSED in tpm_ibmvtpm_send()
tpm_ibmvtpm_send() can fail during PowerVM Live Partition Mobility resume
with an H_CLOSED return from ibmvtpm_send_crq(). The PAPR says, 'The
"partner partition suspended" transport event disables the associated CRQ
such that any H_SEND_CRQ hcall() to the associated CRQ returns H_Closed
until the CRQ has been explicitly enabled using the H_ENABLE_CRQ hcall.'
This patch adds a check in tpm_ibmvtpm_send() for an H_CLOSED return from
ibmvtpm_send_crq() and in that case calls tpm_ibmvtpm_resume() and
retries the ibmvtpm_send_crq() once.
Cc: stable@vger.kernel.org # 3.7.x
Fixes: 132f76294744 ("drivers/char/tpm: Add new device driver to support IBM vTPM")
Reported-by: Linh Pham <phaml@us.ibm.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: George Wilson <gcwilson@linux.ibm.com>
Tested-by: Linh Pham <phaml@us.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Stefan Berger [Thu, 19 Mar 2020 01:00:17 +0000 (21:00 -0400)]
tpm: Export tpm2_get_cc_attrs_tbl for ibmvtpm driver as module
This patch fixes the following problem when the ibmvtpm driver
is built as a module:
ERROR: modpost: "tpm2_get_cc_attrs_tbl" [drivers/char/tpm/tpm_ibmvtpm.ko] undefined!
make[1]: *** [scripts/Makefile.modpost:94: __modpost] Error 1
make: *** [Makefile:1298: modules] Error 2
Fixes: 18b3670d79ae ("tpm: ibmvtpm: Add support for TPM2")
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Michael S. Tsirkin [Mon, 6 Apr 2020 12:12:47 +0000 (08:12 -0400)]
vhost: disable for OABI
vhost is currently broken on the some ARM configs.
The reason is that the ring element addresses are passed between
components with different alignments assumptions. Thus, if
guest selects a pointer and host then gets and dereferences
it, then alignment assumed by the host's compiler might be
greater than the actual alignment of the pointer.
compiler on the host from assuming pointer is aligned.
This actually triggers on ARM with -mabi=apcs-gnu - which is a
deprecated configuration. With this OABI, compiler assumes that
all structures are 4 byte aligned - which is stronger than
virtio guarantees for available and used rings, which are
merely 2 bytes. Thus a guest without -mabi=apcs-gnu running
on top of host with -mabi=apcs-gnu will be broken.
The correct fix is to force alignment of structures - however
that is an intrusive fix that's best deferred until the next release.
We didn't previously support such ancient systems at all - this surfaced
after vdpa support prompted removing dependency of vhost on
VIRTULIZATION. So for now, let's just add something along the lines of
depends on !ARM || AEABI
to the virtio Kconfig declaration, and add a comment that it has to do
with struct member alignment.
Note: we can't make VHOST and VHOST_RING themselves have
a dependency since these are selected. Add a new symbol for that.
We should be able to drop this dependency down the road.
Fixes: 20c384f1ea1a0bc7 ("vhost: refine vhost and vringh kconfig")
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Suggested-by: Richard Earnshaw <Richard.Earnshaw@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Claudio Imbrenda [Fri, 17 Apr 2020 15:29:36 +0000 (17:29 +0200)]
MAINTAINERS: add a reviewer for KVM/s390
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20200417152936.772256-1-imbrenda@linux.ibm.com
Eric Farman [Wed, 15 Apr 2020 19:03:53 +0000 (21:03 +0200)]
KVM: s390: Fix PV check in deliverable_irqs()
The diag 0x44 handler, which handles a directed yield, goes into a
a codepath that does a kvm_for_each_vcpu() and ultimately
deliverable_irqs(). The new check for kvm_s390_pv_cpu_is_protected()
contains an assertion that the vcpu->mutex is held, which isn't going
to be the case in this scenario.
The result is a plethora of these messages if the lock debugging
is enabled, and thus an implication that we have a problem.
WARNING: CPU: 9 PID: 16167 at arch/s390/kvm/kvm-s390.h:239 deliverable_irqs+0x1c6/0x1d0 [kvm]
...snip...
Call Trace:
[<
000003ff80429bf2>] deliverable_irqs+0x1ca/0x1d0 [kvm]
([<
000003ff80429b34>] deliverable_irqs+0x10c/0x1d0 [kvm])
[<
000003ff8042ba82>] kvm_s390_vcpu_has_irq+0x2a/0xa8 [kvm]
[<
000003ff804101e2>] kvm_arch_dy_runnable+0x22/0x38 [kvm]
[<
000003ff80410284>] kvm_vcpu_on_spin+0x8c/0x1d0 [kvm]
[<
000003ff80436888>] kvm_s390_handle_diag+0x3b0/0x768 [kvm]
[<
000003ff80425af4>] kvm_handle_sie_intercept+0x1cc/0xcd0 [kvm]
[<
000003ff80422bb0>] __vcpu_run+0x7b8/0xfd0 [kvm]
[<
000003ff80423de6>] kvm_arch_vcpu_ioctl_run+0xee/0x3e0 [kvm]
[<
000003ff8040ccd8>] kvm_vcpu_ioctl+0x2c8/0x8d0 [kvm]
[<
00000001504ced06>] ksys_ioctl+0xae/0xe8
[<
00000001504cedaa>] __s390x_sys_ioctl+0x2a/0x38
[<
0000000150cb9034>] system_call+0xd8/0x2d8
2 locks held by CPU 2/KVM/16167:
#0:
00000001951980c0 (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0x90/0x8d0 [kvm]
#1:
000000019599c0f0 (&kvm->srcu){....}, at: __vcpu_run+0x4bc/0xfd0 [kvm]
Last Breaking-Event-Address:
[<
000003ff80429b34>] deliverable_irqs+0x10c/0x1d0 [kvm]
irq event stamp: 11967
hardirqs last enabled at (11975): [<
00000001502992f2>] console_unlock+0x4ca/0x650
hardirqs last disabled at (11982): [<
0000000150298ee8>] console_unlock+0xc0/0x650
softirqs last enabled at (7940): [<
0000000150cba6ca>] __do_softirq+0x422/0x4d8
softirqs last disabled at (7929): [<
00000001501cd688>] do_softirq_own_stack+0x70/0x80
Considering what's being done here, let's fix this by removing the
mutex assertion rather than acquiring the mutex for every other vcpu.
Fixes: 201ae986ead7 ("KVM: s390: protvirt: Implement interrupt injection")
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/20200415190353.63625-1-farman@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Linus Torvalds [Sun, 19 Apr 2020 21:35:30 +0000 (14:35 -0700)]
Linux 5.7-rc2
Brian Geffon [Fri, 17 Apr 2020 17:25:56 +0000 (10:25 -0700)]
mm: Fix MREMAP_DONTUNMAP accounting on VMA merge
When remapping a mapping where a portion of a VMA is remapped
into another portion of the VMA it can cause the VMA to become
split. During the copy_vma operation the VMA can actually
be remerged if it's an anonymous VMA whose pages have not yet
been faulted. This isn't normally a problem because at the end
of the remap the original portion is unmapped causing it to
become split again.
However, MREMAP_DONTUNMAP leaves that original portion in place which
means that the VMA which was split and then remerged is not actually
split at the end of the mremap. This patch fixes a bug where
we don't detect that the VMAs got remerged and we end up
putting back VM_ACCOUNT on the next mapping which is completely
unreleated. When that next mapping is unmapped it results in
incorrectly unaccounting for the memory which was never accounted,
and eventually we will underflow on the memory comittment.
There is also another issue which is similar, we're currently
accouting for the number of pages in the new_vma but that's wrong.
We need to account for the length of the remap operation as that's
all that is being added. If there was a mapping already at that
location its comittment would have been adjusted as part of
the munmap at the start of the mremap.
A really simple repro can be seen in:
https://gist.github.com/bgaff/
e101ce99da7d9a8c60acc641d07f312c
Fixes: e346b3813067 ("mm/mremap: add MREMAP_DONTUNMAP to mremap()")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Brian Geffon <bgeffon@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Sun, 19 Apr 2020 20:59:06 +0000 (13:59 -0700)]
Merge tag 'clk-fixes-for-linus' of git://git./linux/kernel/git/clk/linux
Pull clk fixes from Stephen Boyd:
"Two build fixes for a couple clk drivers and a fix for the Unisoc
serial clk where we want to keep it on for earlycon"
* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
clk: sprd: don't gate uart console clock
clk: mmp2: fix link error without mmp2
clk: asm9260: fix __clk_hw_register_fixed_rate_with_accuracy typo
Linus Torvalds [Sun, 19 Apr 2020 18:58:32 +0000 (11:58 -0700)]
Merge tag 'x86-urgent-2020-04-19' of git://git./linux/kernel/git/tip/tip
Pull x86 and objtool fixes from Thomas Gleixner:
"A set of fixes for x86 and objtool:
objtool:
- Ignore the double UD2 which is emitted in BUG() when
CONFIG_UBSAN_TRAP is enabled.
- Support clang non-section symbols in objtool ORC dump
- Fix switch table detection in .text.unlikely
- Make the BP scratch register warning more robust.
x86:
- Increase microcode maximum patch size for AMD to cope with new CPUs
which have a larger patch size.
- Fix a crash in the resource control filesystem when the removal of
the default resource group is attempted.
- Preserve Code and Data Prioritization enabled state accross CPU
hotplug.
- Update split lock cpu matching to use the new X86_MATCH macros.
- Change the split lock enumeration as Intel finaly decided that the
IA32_CORE_CAPABILITIES bits are not architectural contrary to what
the SDM claims. !@#%$^!
- Add Tremont CPU models to the split lock detection cpu match.
- Add a missing static attribute to make sparse happy"
* tag 'x86-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/split_lock: Add Tremont family CPU models
x86/split_lock: Bits in IA32_CORE_CAPABILITIES are not architectural
x86/resctrl: Preserve CDP enable over CPU hotplug
x86/resctrl: Fix invalid attempt at removing the default resource group
x86/split_lock: Update to use X86_MATCH_INTEL_FAM6_MODEL()
x86/umip: Make umip_insns static
x86/microcode/AMD: Increase microcode PATCH_MAX_SIZE
objtool: Make BP scratch register warning more robust
objtool: Fix switch table detection in .text.unlikely
objtool: Support Clang non-section symbols in ORC generation
objtool: Support Clang non-section symbols in ORC dump
objtool: Fix CONFIG_UBSAN_TRAP unreachable warnings
Linus Torvalds [Sun, 19 Apr 2020 18:46:21 +0000 (11:46 -0700)]
Merge tag 'timers-urgent-2020-04-19' of git://git./linux/kernel/git/tip/tip
Pull time namespace fix from Thomas Gleixner:
"An update for the proc interface of time namespaces: Use symbolic
names instead of clockid numbers. The usability nuisance of numbers
was noticed by Michael when polishing the man page"
* tag 'timers-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsets
Linus Torvalds [Sun, 19 Apr 2020 18:28:01 +0000 (11:28 -0700)]
Merge tag 'perf-urgent-2020-04-19' of git://git./linux/kernel/git/tip/tip
Pull perf tooling fixes and updates from Thomas Gleixner:
- Fix the header line of perf stat output for '--metric-only --per-socket'
- Fix the python build with clang
- The usual tools UAPI header synchronization
* tag 'perf-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tools headers: Synchronize linux/bits.h with the kernel sources
tools headers: Adopt verbatim copy of compiletime_assert() from kernel sources
tools headers: Update x86's syscall_64.tbl with the kernel sources
tools headers UAPI: Sync drm/i915_drm.h with the kernel sources
tools headers UAPI: Update tools's copy of drm.h headers
tools headers kvm: Sync linux/kvm.h with the kernel sources
tools headers UAPI: Sync linux/fscrypt.h with the kernel sources
tools include UAPI: Sync linux/vhost.h with the kernel sources
tools arch x86: Sync asm/cpufeatures.h with the kernel sources
tools headers UAPI: Sync linux/mman.h with the kernel
tools headers UAPI: Sync sched.h with the kernel
tools headers: Update linux/vdso.h and grab a copy of vdso/const.h
perf stat: Fix no metric header if --per-socket and --metric-only set
perf python: Check if clang supports -fno-semantic-interposition
tools arch x86: Sync the msr-index.h copy with the kernel sources
Linus Torvalds [Sun, 19 Apr 2020 18:23:33 +0000 (11:23 -0700)]
Merge tag 'irq-urgent-2020-04-19' of git://git./linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
"A set of fixes/updates for the interrupt subsystem:
- Remove setup_irq() and remove_irq(). All users have been converted
so remove them before new users surface.
- A set of bugfixes for various interrupt chip drivers
- Add a few missing static attributes to address sparse warnings"
* tag 'irq-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/irq-bcm7038-l1: Make bcm7038_l1_of_init() static
irqchip/irq-mvebu-icu: Make legacy_bindings static
irqchip/meson-gpio: Fix HARDIRQ-safe -> HARDIRQ-unsafe lock order
irqchip/sifive-plic: Fix maximum priority threshold value
irqchip/ti-sci-inta: Fix processing of masked irqs
irqchip/mbigen: Free msi_desc on device teardown
irqchip/gic-v4.1: Update effective affinity of virtual SGIs
irqchip/gic-v4.1: Add support for VPENDBASER's Dirty+Valid signaling
genirq: Remove setup_irq() and remove_irq()
Linus Torvalds [Sun, 19 Apr 2020 18:18:20 +0000 (11:18 -0700)]
Merge tag 'sched-urgent-2020-04-19' of git://git./linux/kernel/git/tip/tip
Pull scheduler fixes from Thomas Gleixner:
"Two fixes for the scheduler:
- Work around an uninitialized variable warning where GCC can't
figure it out.
- Allow 'isolcpus=' to skip unknown subparameters so that older
kernels work with the commandline of a newer kernel. Improve the
error output while at it"
* tag 'sched-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/vtime: Work around an unitialized variable warning
sched/isolation: Allow "isolcpus=" to skip unknown sub-parameters
Linus Torvalds [Sun, 19 Apr 2020 18:16:00 +0000 (11:16 -0700)]
Merge tag 'core-urgent-2020-04-19' of git://git./linux/kernel/git/tip/tip
Pull RCU fix from Thomas Gleixner:
"A single bugfix for RCU to prevent taking a lock in NMI context"
* tag 'core-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rcu: Don't acquire lock in NMI handler in rcu_nmi_enter_common()
Linus Torvalds [Sun, 19 Apr 2020 18:05:15 +0000 (11:05 -0700)]
Merge tag 'ext4_for_linus_stable' of git://git./linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o:
"Miscellaneous bug fixes and cleanups for ext4, including a fix for
generic/388 in data=journal mode, removing some BUG_ON's, and cleaning
up some compiler warnings"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: convert BUG_ON's to WARN_ON's in mballoc.c
ext4: increase wait time needed before reuse of deleted inode numbers
ext4: remove set but not used variable 'es' in ext4_jbd2.c
ext4: remove set but not used variable 'es'
ext4: do not zeroout extents beyond i_disksize
ext4: fix return-value types in several function comments
ext4: use non-movable memory for superblock readahead
ext4: use matching invalidatepage in ext4_writepage
Linus Torvalds [Sun, 19 Apr 2020 18:00:27 +0000 (11:00 -0700)]
Merge tag '5.7-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Three small smb3 fixes: two debug related (helping network tracing for
SMB2 mounts, and the other removing an unintended debug line on
signing failures), and one fixing a performance problem with 64K
pages"
* tag '5.7-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb3: remove overly noisy debug line in signing errors
cifs: improve read performance for page size 64KB & cache=strict & vers=2.1+
cifs: dump the session id and keys also for SMB2 sessions
Linus Torvalds [Sun, 19 Apr 2020 17:34:30 +0000 (10:34 -0700)]
Merge tag 'flexible-array-member-5.7-rc2' of git://git./linux/kernel/git/gustavoars/linux
Pull flexible-array member conversion from Gustavo Silva:
"The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array
member[1][2], introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof
operator may not be applied. As a quirk of the original
implementation of zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible
array members have incomplete type[1]. There are some instances of
code in which the sizeof operator is being incorrectly/erroneously
applied to zero-length arrays and the result is zero. Such instances
may be hiding some bugs. So, this work (flexible-array member
convertions) will also help to get completely rid of those sorts of
issues.
Notice that all of these patches have been baking in linux-next for
quite a while now and, 238 more of these patches have already been
merged into 5.7-rc1.
There are a couple hundred more of these issues waiting to be
addressed in the whole codebase"
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
* tag 'flexible-array-member-5.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: (28 commits)
xattr.h: Replace zero-length array with flexible-array member
uapi: linux: fiemap.h: Replace zero-length array with flexible-array member
uapi: linux: dlm_device.h: Replace zero-length array with flexible-array member
tpm_eventlog.h: Replace zero-length array with flexible-array member
ti_wilink_st.h: Replace zero-length array with flexible-array member
swap.h: Replace zero-length array with flexible-array member
skbuff.h: Replace zero-length array with flexible-array member
sched: topology.h: Replace zero-length array with flexible-array member
rslib.h: Replace zero-length array with flexible-array member
rio.h: Replace zero-length array with flexible-array member
posix_acl.h: Replace zero-length array with flexible-array member
platform_data: wilco-ec.h: Replace zero-length array with flexible-array member
memcontrol.h: Replace zero-length array with flexible-array member
list_lru.h: Replace zero-length array with flexible-array member
lib: cpu_rmap: Replace zero-length array with flexible-array member
irq.h: Replace zero-length array with flexible-array member
ihex.h: Replace zero-length array with flexible-array member
igmp.h: Replace zero-length array with flexible-array member
genalloc.h: Replace zero-length array with flexible-array member
ethtool.h: Replace zero-length array with flexible-array member
...
Linus Torvalds [Sat, 18 Apr 2020 21:03:12 +0000 (14:03 -0700)]
Merge tag 'scsi-fixes' of git://git./linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Seven fixes: three in target, one on a sg error leg, two in qla2xxx
fixing warnings introduced in the last merge window and updating
MAINTAINERS and one in hisi_sas fixing a problem introduced by libata"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: sg: add sg_remove_request in sg_common_write
scsi: target: tcmu: reset_ring should reset TCMU_DEV_BIT_BROKEN
scsi: target: fix PR IN / READ FULL STATUS for FC
scsi: target: Write NULL to *port_nexus_ptr if no ISID
scsi: MAINTAINERS: Update qla2xxx FC-SCSI driver maintainer
scsi: qla2xxx: Fix regression warnings
scsi: hisi_sas: Fix build error without SATA_HOST
Gustavo A. R. Silva [Tue, 24 Mar 2020 00:41:14 +0000 (19:41 -0500)]
xattr.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Tue, 24 Mar 2020 02:30:22 +0000 (21:30 -0500)]
uapi: linux: fiemap.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Tue, 24 Mar 2020 00:51:46 +0000 (19:51 -0500)]
uapi: linux: dlm_device.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Tue, 24 Mar 2020 00:38:18 +0000 (19:38 -0500)]
tpm_eventlog.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Tue, 24 Mar 2020 00:25:06 +0000 (19:25 -0500)]
ti_wilink_st.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Tue, 24 Mar 2020 00:23:10 +0000 (19:23 -0500)]
swap.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Tue, 24 Mar 2020 00:22:24 +0000 (19:22 -0500)]
skbuff.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Tue, 24 Mar 2020 00:14:37 +0000 (19:14 -0500)]
sched: topology.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Tue, 24 Mar 2020 00:13:20 +0000 (19:13 -0500)]
rslib.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Tue, 24 Mar 2020 00:12:17 +0000 (19:12 -0500)]
rio.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Tue, 24 Mar 2020 00:08:58 +0000 (19:08 -0500)]
posix_acl.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Tue, 24 Mar 2020 00:07:49 +0000 (19:07 -0500)]
platform_data: wilco-ec.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Mon, 23 Mar 2020 23:36:10 +0000 (18:36 -0500)]
memcontrol.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Mon, 23 Mar 2020 23:32:01 +0000 (18:32 -0500)]
list_lru.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Mon, 23 Mar 2020 21:58:49 +0000 (16:58 -0500)]
lib: cpu_rmap: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Gustavo A. R. Silva [Mon, 23 Mar 2020 23:01:11 +0000 (18:01 -0500)]
irq.h: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit
76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
projects / openwrt / staging / blogic.git / log