On Wed, Dec 6, 2023 at 4:05 PM Hangbin Liu liuhangbin@gmail.com wrote:

On Wed, Dec 06, 2023 at 01:37:18PM +0100, Florent Revest wrote:

...

In __team_options_register, team_options are allocated and appended to the team's option_list. If one option instance allocation fails, the "inst_rollback" cleanup path frees the previously allocated options but doesn't remove them from the team's option_list. This leaves dangling pointers that can be dereferenced later by other parts of the team driver that iterate over options.

This patch fixes the cleanup path to remove the dangling pointers from the list.

As far as I can tell, this uaf doesn't have much security implications since it would be fairly hard to exploit (an attacker would need to make the allocation of that specific small object fail) but it's still nice to fix.

Fixes: 80f7c6683fe0 ("team: add support for per-port options") Signed-off-by: Florent Revest revest@chromium.org

Reviewed-by: Hangbin Liu liuhangbin@gmail.com

Thank you for the quick reviews Hangbin & Jiri, I appreciate! :)

I just realized I forgot to CC stable (like I always do... :) maybe I should tattoo it on my arm) Let me know if you'd like a v2 adding:

Cc: stable@vger.kernel.org