valis 1c8262f31f net/sched: cls_route: No longer copy tcf_result on update to avoid use-after-free
[ Upstream commit b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8 ]

When route4_change() is called on an existing filter, the whole
tcf_result struct is always copied into the new instance of the filter.

This causes a problem when updating a filter bound to a class,
as tcf_unbind_filter() is always called on the old instance in the
success path, decreasing filter_cnt of the still referenced class
and allowing it to be deleted, leading to a use-after-free.

Fix this by no longer copying the tcf_result struct from the old filter.

Fixes: 1109c00547fc ("net: sched: RCU cls_route")
Reported-by: valis <sec@valis.email>
Reported-by: Bing-Jhong Billy Jheng <billy@starlabs.sg>
Signed-off-by: valis <sec@valis.email>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: Victor Nogueira <victor@mojatatu.com>
Reviewed-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: M A Ramdhan <ramdhan@starlabs.sg>
Link: https://lore.kernel.org/r/20230729123202.72406-4-jhs@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-11 11:53:56 +02:00
..
2023-06-09 10:28:59 +02:00
2022-04-20 09:19:40 +02:00
2023-07-27 08:37:40 +02:00
2023-06-21 15:44:10 +02:00
2023-01-18 11:41:09 +01:00
2023-05-17 11:35:59 +02:00
2023-07-27 08:37:23 +02:00
2021-06-18 09:59:00 +02:00
2023-06-21 15:44:10 +02:00
2023-06-21 15:44:10 +02:00