0-day reported the strncpy error below:
../kernel/trace/trace_events_synth.c: In function 'last_cmd_set':
../kernel/trace/trace_events_synth.c:65:9: warning: 'strncpy' specified bound depends on the length o\
f the source argument [-Wstringop-truncation]
65 | strncpy(last_cmd, str, strlen(str) + 1);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../kernel/trace/trace_events_synth.c:65:32: note: length computed here
65 | strncpy(last_cmd, str, strlen(str) + 1);
| ^~~~~~~~~~~
There's no reason to use strncpy here, in fact there's no reason to do
anything but a simple kstrdup() (note we don't even need to check for
failure since last_cmod is expected to be either the last cmd string
or NULL, and the containing function is a void return).
Fixes: 27c888da9867 ("tracing: Remove size restriction on synthetic event cmd error logging")
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Tom Zanussi <[email protected]>
---
kernel/trace/trace_events_synth.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c
index fdd79e07e2fc..5e8c07aef071 100644
--- a/kernel/trace/trace_events_synth.c
+++ b/kernel/trace/trace_events_synth.c
@@ -58,11 +58,8 @@ static void last_cmd_set(const char *str)
return;
kfree(last_cmd);
- last_cmd = kzalloc(strlen(str) + 1, GFP_KERNEL);
- if (!last_cmd)
- return;
- strncpy(last_cmd, str, strlen(str) + 1);
+ last_cmd = kstrdup(str, GFP_KERNEL);
}
static void synth_err(u8 err_type, u16 err_pos)
--
2.17.1