diff options
author | Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> | 2022-06-09 16:03:28 +0530 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2022-06-18 10:19:10 +1000 |
commit | ec6d0dde71d760aa60316f8d1c9a1b0d99213529 (patch) | |
tree | c8dee70d88ddb7bc8393d883d52379eca5fbc4a3 /arch | |
parent | e561e472a3d441753bd012333b057f48fef1045b (diff) |
powerpc: Enable execve syscall exit tracepoint
On execve[at], we are zero'ing out most of the thread register state
including gpr[0], which contains the syscall number. Due to this, we
fail to trigger the syscall exit tracepoint properly. Fix this by
retaining gpr[0] in the thread register state.
Before this patch:
# tail /sys/kernel/debug/tracing/trace
cat-123 [000] ..... 61.449351: sys_execve(filename:
7fffa6b23448, argv: 7fffa6b233e0, envp: 7fffa6b233f8)
cat-124 [000] ..... 62.428481: sys_execve(filename:
7fffa6b23448, argv: 7fffa6b233e0, envp: 7fffa6b233f8)
echo-125 [000] ..... 65.813702: sys_execve(filename:
7fffa6b23378, argv: 7fffa6b233a0, envp: 7fffa6b233b0)
echo-125 [000] ..... 65.822214: sys_execveat(fd: 0,
filename: 1009ac48, argv: 7ffff65d0c98, envp: 7ffff65d0ca8, flags: 0)
After this patch:
# tail /sys/kernel/debug/tracing/trace
cat-127 [000] ..... 100.416262: sys_execve(filename:
7fffa41b3448, argv: 7fffa41b33e0, envp: 7fffa41b33f8)
cat-127 [000] ..... 100.418203: sys_execve -> 0x0
echo-128 [000] ..... 103.873968: sys_execve(filename:
7fffa41b3378, argv: 7fffa41b33a0, envp: 7fffa41b33b0)
echo-128 [000] ..... 103.875102: sys_execve -> 0x0
echo-128 [000] ..... 103.882097: sys_execveat(fd: 0,
filename: 1009ac48, argv: 7fffd10d2148, envp: 7fffd10d2158, flags: 0)
echo-128 [000] ..... 103.883225: sys_execveat -> 0x0
Cc: stable@vger.kernel.org
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Tested-by: Sumit Dubey2 <Sumit.Dubey2@ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220609103328.41306-1-naveen.n.rao@linux.vnet.ibm.com
Diffstat (limited to 'arch')
-rw-r--r-- | arch/powerpc/kernel/process.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index ee0433809621..0fbda89cd1bb 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -1855,7 +1855,7 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp) tm_reclaim_current(0); #endif - memset(regs->gpr, 0, sizeof(regs->gpr)); + memset(®s->gpr[1], 0, sizeof(regs->gpr) - sizeof(regs->gpr[0])); regs->ctr = 0; regs->link = 0; regs->xer = 0; |