From: Florent Revest Date: Wed, 6 Dec 2023 12:37:18 +0000 (+0100) Subject: team: Fix use-after-free when an option instance allocation fails X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=c12296bbecc488623b7d1932080e394d08f3226b;p=linux.git team: Fix use-after-free when an option instance allocation fails 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. Cc: stable@vger.kernel.org Fixes: 80f7c6683fe0 ("team: add support for per-port options") Signed-off-by: Florent Revest Reviewed-by: Jiri Pirko Reviewed-by: Hangbin Liu Link: https://lore.kernel.org/r/20231206123719.1963153-1-revest@chromium.org Signed-off-by: Jakub Kicinski --- diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c index 508d9a392ab18..f575f225d4178 100644 --- a/drivers/net/team/team.c +++ b/drivers/net/team/team.c @@ -281,8 +281,10 @@ static int __team_options_register(struct team *team, return 0; inst_rollback: - for (i--; i >= 0; i--) + for (i--; i >= 0; i--) { __team_option_inst_del_option(team, dst_opts[i]); + list_del(&dst_opts[i]->list); + } i = option_count; alloc_rollback: