Commit adb25a46 authored by Shivani Gupta's avatar Shivani Gupta Committed by Jakub Kicinski
Browse files

net/sched: act_api: avoid dereferencing ERR_PTR in tcf_idrinfo_destroy 

syzbot reported a crash in tc_act_in_hw() during netns teardown where
tcf_idrinfo_destroy() passed an ERR_PTR(-EBUSY) value as a tc_action
pointer, leading to an invalid dereference.

Guard against ERR_PTR entries when iterating the action IDR so teardown
does not call tc_act_in_hw() on an error pointer.

Fixes: 84a7d679 ("net/sched: acp_api: no longer acquire RTNL in tc_action_net_exit()")
Link: https://syzkaller.appspot.com/bug?extid=8f1c492ffa4644ff3826


Reported-by: default avatar <syzbot+8f1c492ffa4644ff3826@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=8f1c492ffa4644ff3826


Signed-off-by: default avatarShivani Gupta <shivani07g@gmail.com>
Link: https://patch.msgid.link/20260105005905.243423-1-shivani07g@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 13ff3e72

net/sched/act_api.c

+2 −0
Original line number Diff line number Diff line
@@ -940,6 +940,8 @@ void tcf_idrinfo_destroy(const struct tc_action_ops *ops, 
	int ret;



	idr_for_each_entry_ul(idr, p, tmp, id) {

		if (IS_ERR(p))

			continue;

		if (tc_act_in_hw(p) && !mutex_taken) {

			rtnl_lock();

			mutex_taken = true;