This is a note to let you know that I've just added the patch titled team: Fix use-after-free when an option instance allocation fails to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: team-fix-use-after-free-when-an-option-instance-allocation-fails.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c12296bbecc488623b7d1932080e394d08f3226b Mon Sep 17 00:00:00 2001 From: Florent Revest <revest@xxxxxxxxxxxx> Date: Wed, 6 Dec 2023 13:37:18 +0100 Subject: team: Fix use-after-free when an option instance allocation fails From: Florent Revest <revest@xxxxxxxxxxxx> commit c12296bbecc488623b7d1932080e394d08f3226b upstream. 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@xxxxxxxxxxxxxxx Fixes: 80f7c6683fe0 ("team: add support for per-port options") Signed-off-by: Florent Revest <revest@xxxxxxxxxxxx> Reviewed-by: Jiri Pirko <jiri@xxxxxxxxxx> Reviewed-by: Hangbin Liu <liuhangbin@xxxxxxxxx> Link: https://lore.kernel.org/r/20231206123719.1963153-1-revest@xxxxxxxxxxxx Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/team/team.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/net/team/team.c +++ b/drivers/net/team/team.c @@ -284,8 +284,10 @@ static int __team_options_register(struc 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: Patches currently in stable-queue which might be from revest@xxxxxxxxxxxx are queue-5.4/team-fix-use-after-free-when-an-option-instance-allocation-fails.patch