On Mon, 19 Jan 2026 11:45:42 +0000
Weigang He <[email protected]> wrote:
> When realloc() fails in add_string(), the function returns -1 but leaves
> *vals pointing to the previously allocated memory. This can cause memory
> leaks in callers like make_trace_array() that return on error without
> freeing the partially built array.
>
> Fix this by freeing *vals and setting it to NULL when realloc() fails.
> This makes the error handling self-contained in add_string() so callers
> don't need to handle cleanup on failure.
This looks not enough. If the memory allocation is failed, it should NOT
continue anything.
I think we need to make the command itself failure when it fails to
allocate memory, as below:
diff --git a/scripts/tracepoint-update.c b/scripts/tracepoint-update.c
index 90046aedc97b..1b4129a21942 100644
--- a/scripts/tracepoint-update.c
+++ b/scripts/tracepoint-update.c
@@ -94,7 +94,7 @@ static void make_trace_array(struct elf_tracepoint *etrace)
if (!len)
continue;
if (add_string(str, &vals, &count) < 0)
- return;
+ exit(EXIT_FAILURE);
}
/* If CONFIG_TRACEPOINT_VERIFY_USED is not set, there's nothing to do */
Thank you,
>
> This bug is found by my static analysis tool and my code review.
>
> Signed-off-by: Weigang He <[email protected]>
> ---
> scripts/tracepoint-update.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/scripts/tracepoint-update.c b/scripts/tracepoint-update.c
> index 90046aedc97b9..5cf43c0aac891 100644
> --- a/scripts/tracepoint-update.c
> +++ b/scripts/tracepoint-update.c
> @@ -49,6 +49,8 @@ static int add_string(const char *str, const char ***vals,
> int *count)
> array = realloc(array, sizeof(char *) * size);
> if (!array) {
> fprintf(stderr, "Failed memory allocation\n");
> + free(*vals);
> + *vals = NULL;
> return -1;
> }
> *vals = array;
> --
> 2.34.1
>
--
Masami Hiramatsu (Google) <[email protected]>
