From: Daniel T. Lee danieltimlee@gmail.com
[ Upstream commit d59dd69d5576d699d7d3f5da0b4738c3a36d0133 ]
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 Signed-off-by: Sasha Levin sashal@kernel.org --- samples/bpf/bpf_load.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c index 5061a2ec45646..176c04a454dc9 100644 --- a/samples/bpf/bpf_load.c +++ b/samples/bpf/bpf_load.c @@ -59,7 +59,9 @@ static int write_kprobe_events(const char *val) { 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;