Re: [PATCH v2] perf unwind: handle allocation failure in libdw__get_entries()

[Namhyung Kim <namhyung@kernel.org>]

On Tue, Aug 18, 2026 at 02:48:37PM +0000, Triet Hoang wrote:
> Check the return value of zalloc() before dereferencing the allocated
> dwfl_ui_ti structure.
> 
> Return -ENOMEM when the allocation fails to avoid a NULL pointer
> dereference.
> 
> Signed-off-by: Triet Hoang <triet.hoang.dev@gmail.com>

Acked-by: Namhyung Kim <namhyung@kernel.org>

Thanks,
Namhyung

> ---
> Changes in v2:
> - Free the ui structure before returning -ENOMEM to avoid memory leak.
> ---
>  tools/perf/util/unwind-libdw.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/tools/perf/util/unwind-libdw.c b/tools/perf/util/unwind-libdw.c
> index 7f35042be567..fd8a5125468c 100644
> --- a/tools/perf/util/unwind-libdw.c
> +++ b/tools/perf/util/unwind-libdw.c
> @@ -379,6 +379,11 @@ int libdw__get_entries(unwind_entry_cb_t cb, void *arg,
>  		dwfl = dwfl_ui_ti->dwfl;
>  	} else {
>  		dwfl_ui_ti = zalloc(sizeof(*dwfl_ui_ti));
> +		if (!dwfl_ui_ti) {
> +			free(ui);
> +			return -ENOMEM;
> +		}
> +
>  		dwfl = dwfl_begin(&offline_callbacks);
>  		if (!dwfl)
>  			goto out;
> -- 
> 2.53.0
>