diff options
author | valis <sec@valis.email> | 2023-07-29 08:32:01 -0400 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-09-23 10:48:17 +0200 |
commit | 4f38dc8496d1991e2c055a0068dd98fb48affcc6 (patch) | |
tree | ce4691b75fdda05917e1fcbce3bb995308cea872 | |
parent | 55e55d7fa5356eea32939617d72f68e5c8b34702 (diff) |
net/sched: cls_fw: No longer copy tcf_result on update to avoid use-after-free
commit 76e42ae831991c828cffa8c37736ebfb831ad5ec upstream.
When fw_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: e35a8ee5993b ("net: sched: fw use RCU")
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/20230729123202.72406-3-jhs@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ Fixed small conflict as 'fnew->ifindex' assignment is not protected by
CONFIG_NET_CLS_IND on upstream since a51486266c3 ]
Signed-off-by: Luiz Capitulino <luizcap@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | net/sched/cls_fw.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/net/sched/cls_fw.c b/net/sched/cls_fw.c index 5284a473c697..f15089c24a32 100644 --- a/net/sched/cls_fw.c +++ b/net/sched/cls_fw.c @@ -277,7 +277,6 @@ static int fw_change(struct net *net, struct sk_buff *in_skb, return -ENOBUFS; fnew->id = f->id; - fnew->res = f->res; #ifdef CONFIG_NET_CLS_IND fnew->ifindex = f->ifindex; #endif /* CONFIG_NET_CLS_IND */ |