team: Fix use-after-free when an option instance allocation fails
authorFlorent Revest <revest@chromium.org>
Wed, 6 Dec 2023 12:37:18 +0000 (13:37 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 20 Dec 2023 16:02:02 +0000 (17:02 +0100)
commit28b36426b83e35dbfbf3d2104c9aac61c1d8f5df
tree8381e98cb42f99901b667ad9f5d2cde03844de5d
parent2c8a21a124cab4391254680cda796036d061d9b9
team: Fix use-after-free when an option instance allocation fails

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@vger.kernel.org
Fixes: 80f7c6683fe0 ("team: add support for per-port options")
Signed-off-by: Florent Revest <revest@chromium.org>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://lore.kernel.org/r/20231206123719.1963153-1-revest@chromium.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/net/team/team.c