From: Shivani Gupta Date: Mon, 5 Jan 2026 00:59:05 +0000 (+0000) Subject: net/sched: act_api: avoid dereferencing ERR_PTR in tcf_idrinfo_destroy X-Git-Tag: v6.19-rc5~29^2~14 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=adb25a46dc0a43173f5ea5f5f58fc8ba28970c7c;p=thirdparty%2Fkernel%2Flinux.git 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: 84a7d6797e6a ("net/sched: acp_api: no longer acquire RTNL in tc_action_net_exit()") Link: https://syzkaller.appspot.com/bug?extid=8f1c492ffa4644ff3826 Reported-by: syzbot+8f1c492ffa4644ff3826@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=8f1c492ffa4644ff3826 Signed-off-by: Shivani Gupta Link: https://patch.msgid.link/20260105005905.243423-1-shivani07g@gmail.com Signed-off-by: Jakub Kicinski --- diff --git a/net/sched/act_api.c b/net/sched/act_api.c index ff6be5cfe2b0..e1ab0faeb811 100644 --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -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;