samples: bpf: fix: seg fault with NULL pointer arg
When NULL pointer accidentally passed to write_kprobe_events,
due to strlen(NULL), segmentation fault happens.
Changed code returns -1 to deal with this situation.
Bug issued with Smatch, static analysis.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c
index 434ea34..eae7b63 100644
--- a/samples/bpf/bpf_load.c
+++ b/samples/bpf/bpf_load.c
@@ -58,7 +58,9 @@
{
int fd, ret, flags;
- if ((val != NULL) && (val[0] == '\0'))
+ if (val == NULL)
+ return -1;
+ else if (val[0] == '\0')
flags = O_WRONLY | O_TRUNC;
else
flags = O_WRONLY | O_APPEND;