[PATCH] perf util: Fix bad memory access in trace info.

From: cphlipot0
Date: Wed Aug 29 2018 - 02:20:51 EST

From: Chris Phlipot <cphlipot0@xxxxxxxxx>

In the write to the output_fd in the error condition of
record_saved_cmdline(), we are writing 8 bytes from a memory location
on the stack that contains a primitive that is only 4 bytes in size.
Change the primitive to 8 bytes in size to match the size of the write
in order to avoid reading unknown memory from the stack.

Signed-off-by: Chris Phlipot <cphlipot0@xxxxxxxxx>
tools/perf/util/trace-event-info.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c
index c85d0d1a65ed..7b0ca7cbb7de 100644
--- a/tools/perf/util/trace-event-info.c
+++ b/tools/perf/util/trace-event-info.c
@@ -377,7 +377,7 @@ static int record_ftrace_printk(void)

static int record_saved_cmdline(void)
- unsigned int size;
+ unsigned long long size;
char *path;
struct stat st;
int ret, err = 0;