From 6f25b4e75a87fea8087b543f3d1298d301d24ad7 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 16 Aug 2012 18:14:14 +0100 Subject: tracing/syscalls: Fix perf syscall tracing when syscall_nr == -1 commit 60916a9382e88fbf5e54fd36a3e658efd7ab7bed upstream. syscall_get_nr can return -1 in the case that the task is not executing a system call. This patch fixes perf_syscall_{enter,exit} to check that the syscall number is valid before using it as an index into a bitmap. Link: http://lkml.kernel.org/r/1345137254-7377-1-git-send-email-will.deacon@arm.com Cc: Jason Baron Cc: Wade Farnsworth Cc: Frederic Weisbecker Signed-off-by: Will Deacon Signed-off-by: Steven Rostedt Signed-off-by: Ben Hutchings --- kernel/trace/trace_syscalls.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 7c75bbb..22a7c9b 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -519,6 +519,8 @@ static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id) int size; syscall_nr = syscall_get_nr(current, regs); + if (syscall_nr < 0) + return; if (!test_bit(syscall_nr, enabled_perf_enter_syscalls)) return; @@ -593,6 +595,8 @@ static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret) int size; syscall_nr = syscall_get_nr(current, regs); + if (syscall_nr < 0) + return; if (!test_bit(syscall_nr, enabled_perf_exit_syscalls)) return; -- cgit v1.1