On Fri, May 24, 2024 at 12:20:03PM +0800, Zijun Hu wrote:
> zap_modalias_env() wrongly calculates size of memory block
> to move, so maybe cause OOB memory access issue, fixed by
> correcting size to memmove.
"maybe" or "does"? That's a big difference :)
>
> Fixes: 9b3fa47d4a76 ("kobject: fix suppressing modalias in uevents delivered over netlink")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
> ---
> lib/kobject_uevent.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c
> index 03b427e2707e..f153b4f9d4d9 100644
> --- a/lib/kobject_uevent.c
> +++ b/lib/kobject_uevent.c
> @@ -434,7 +434,7 @@ static void zap_modalias_env(struct kobj_uevent_env *env)
>
> if (i != env->envp_idx - 1) {
> memmove(env->envp[i], env->envp[i + 1],
> - env->buflen - len);
> + env->buf + env->buflen - env->envp[i + 1]);
How is this "more correct"? Please explain it better, this logic is not
obvious at all.
thanks,
greg k-h
