The following commit has been merged into the x86/urgent branch of tip:
Commit-ID: 2356bb4b8221d7dc8c7beb810418122ed90254c9
Gitweb:
https://git.kernel.org/tip/2356bb4b8221d7dc8c7beb810418122ed90254c9
Author: Vamshi K Sthambamkadi <vamshi.k.sthambamk...@gmail.com>
AuthorDate: Fri, 28 Aug 2020 17:02:46 +05:30
Committer: Borislav Petkov <b...@suse.de>
CommitterDate: Fri, 04 Sep 2020 14:40:42 +02:00
tracing/kprobes, x86/ptrace: Fix regs argument order for i386
On i386, the order of parameters passed on regs is eax,edx,and ecx
(as per regparm(3) calling conventions).
Change the mapping in regs_get_kernel_argument(), so that arg1=ax
arg2=dx, and arg3=cx.
Running the selftests testcase kprobes_args_use.tc shows the result
as passed.
Fixes: 3c88ee194c28 ("x86: ptrace: Add function argument access API")
Signed-off-by: Vamshi K Sthambamkadi <vamshi.k.sthambamk...@gmail.com>
Signed-off-by: Borislav Petkov <b...@suse.de>
Acked-by: Masami Hiramatsu <mhira...@kernel.org>
Acked-by: Peter Zijlstra (Intel) <pet...@infradead.org>
Cc: <sta...@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200828113242.GA1424@cosmos
---
arch/x86/include/asm/ptrace.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h
index 40aa69d..d8324a2 100644
--- a/arch/x86/include/asm/ptrace.h
+++ b/arch/x86/include/asm/ptrace.h
@@ -327,8 +327,8 @@ static inline unsigned long regs_get_kernel_argument(struct
pt_regs *regs,
static const unsigned int argument_offs[] = {
#ifdef __i386__
offsetof(struct pt_regs, ax),
- offsetof(struct pt_regs, cx),
offsetof(struct pt_regs, dx),
+ offsetof(struct pt_regs, cx),
#define NR_REG_ARGUMENTS 3
#else
offsetof(struct pt_regs, di),
