From nobody Sat Jun 13 13:43:36 2026 Received: from out203-205-221-221.mail.qq.com (out203-205-221-221.mail.qq.com [203.205.221.221]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B45483B6BF0; Thu, 7 May 2026 12:50:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=203.205.221.221 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778158241; cv=none; b=hhhbHWLTpNlg8eCtBObYuU3L/ZvXMol4sIgbfm2JRs/5RODkNhVjZ0LM4KJAN59B40bwK9EZni3vCBzIEt7dX854AqJS6xPkpwH9Sv+WRgSAk0IELUOXeAxNFBoXgSJ0SnVBXWTRe9tly0mSl1r9cVAw+iwLFxi8RLOMdTVsF9o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778158241; c=relaxed/simple; bh=uHD2uCjN1UTQoraWvVy/fg6kCqbQLIutJoDWTGlKUVM=; h=Message-ID:From:To:Cc:Subject:Date:In-Reply-To:References: MIME-Version; b=SmadXXDsSGY/h09N5atpi6bhJeVDM4g8MnccMAR0R9dn+FBv8JhEQBY0/j1sTPvb1qROOiR+qGxwfYQRM5I3eCXJBg1Bs2V9UsUqA6nyTpEfq+2R/8bO1Wo69LbFk8VWMh1WzOCCDIEsyvdQtjLdFWIooHTrXrTuO1ee2e8cRc4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=qq.com; spf=pass smtp.mailfrom=qq.com; dkim=pass (1024-bit key) header.d=qq.com header.i=@qq.com header.b=rr7OduyM; arc=none smtp.client-ip=203.205.221.221 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=qq.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=qq.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=qq.com header.i=@qq.com header.b="rr7OduyM" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qq.com; s=s201512; t=1778158214; bh=5ub2YWhxmtbkh6ASBeqDgX465/eiGKDulnfevlmT57E=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=rr7OduyMYU4DXf7DmYjESFygDNWM7qnufZc27RENxNvqlkwpby6oIZhvSGbd1KB5+ OBtwMjCn8gjiOiRK8iN/KvdQgP0fgUXd42ryHHfR7CJM6/aQwelZUJ/uNqxBMMoL20 yHYJxVI3WSmrSxLf3MY/isKmbZY6DVOiJdY3mr7s= Received: from lxu-ped-host.. ([111.198.231.89]) by newxmesmtplogicsvrsza73-0.qq.com (NewEsmtp) with SMTP id C8A1B40D; Thu, 07 May 2026 20:50:10 +0800 X-QQ-mid: xmsmtpt1778158210t5p0eskuj Message-ID: X-QQ-XMAILINFO: OPDQNGCUQ3qLkaFh7YH4cP0ef7dTVev+OCC4NTAATZsdIfJe5MGyfHz+BKAuMe 25RPII7oaKWNy97i06WpbHAUvoC5MxYIU5A3cshYS3tpyIPgpZZxsKICdfDMRSll03lCGDV4iH3h PeGYuJJGMbuhytycfvHEhmMorKD/h9ol3uLQUe0yiBhp9ptEzUS9wb15obY0FGrJ0B+5fGGhkOL0 zpgFd+TJZ1BtJ2loj2+jiQ6hrCzDeJJnA5Z14C03O+Fsvgpsp0CNOqyLhmGahbZxktH83MJJBGEp ZyfBmNOHxAiv14RkSg4YiDlKoAa3uAPbwxPLdg/oF3WIdcLmL5S1vlvM6AP9aQaYaD2iF/hSJ2VG 9C7O4DDZl2j6AfCEuekmU7c5ifXjGaZuaOeMhm5ifKc51s1SLZIXw6M4JeLQMTK0/sYrPyGfazMe IBzI+KOc2uWkP3Ka+LQyu62pdFcplBjlWWX0Q/2Hk/cGhuKVVj9ZgAKtY+4fxmeWkTVGsWHnzMmA j7Xa4kdm/7XkSqpC2iGBgo/3BZBdLAxuvInt8SKB+l5SSoyyX2VGen9ieUlxnoFrXpcHdu2++/dp +H1JlYMZTzEoAihrdgLN7hrrwS4dT+RDH/fXtFyarOvYxYWIvrpH5dAKP7B2/rbVPbzwsCnNl6gF AieCei0FZM34dGFURjSUPV4rZgR8ML3qrnptpvXhwFWmA30UOYnYrOglUo8efGEh4uymIeXaTx+L CJYUgTibcL4yI3cLXcqqXfcR01CnQMf4VsKRDHkHoDZlMfM53ZvvAGTVG2NhEpVK+JuxRsAyIA08 +aaw5Lbv8wirV6EkLYzKPZG+HEezhBbmJbuyWnGUt4QTNwjUDro84KjM1tM6NeTq2nxzKMiZZ9EV XfyZSEofBSj7rG7zUKjEWRTpFfxydNLWBemMntq75imA+ZzEt/cERcStm5evq2yXQ+IkfH1U74Ns nsc7H5afldZoonbXWX3veCwtAFW6CO9h8yUKgT092qSz7Jlw2ti1E7HyEdH3HuXuQ8u3qu7ebAUJ EypQS8rYRR2AItdtmlOYlSl4qUKwI= X-QQ-XMRINFO: OD9hHCdaPRBwH5bRRRw8tsiH4UAatJqXfg== From: Edward Adam Davis To: syzbot+d8f76778263ab65c2b21@syzkaller.appspotmail.com Cc: akpm@linux-foundation.org, arjan@linux.intel.com, davem@davemloft.net, dsahern@kernel.org, edumazet@google.com, hdanton@sina.com, horms@kernel.org, jgg@ziepe.ca, kuba@kernel.org, kuni1840@gmail.com, kuniyu@google.com, leon@kernel.org, linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, syzkaller-bugs@googlegroups.com, yanjun.zhu@linux.dev, zyjzyj2000@gmail.com Subject: [PATCH] RDMA/nldev: add mutual exclusion in nldev_dellink() Date: Thu, 7 May 2026 20:50:10 +0800 X-OQ-MSGID: <20260507125009.109737-2-eadavis@qq.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <69fc0c7c.a00a0220.387fc1.0006.GAE@google.com> References: <69fc0c7c.a00a0220.387fc1.0006.GAE@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" We must serialize calls to nldev_dellink() or risk a crash as syzbot reported: KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027] Call Trace: udp_tunnel_sock_release+0x6d/0x80 net/ipv4/udp_tunnel_core.c:197 rxe_release_udp_tunnel drivers/infiniband/sw/rxe/rxe_net.c:294 [inline] rxe_sock_put drivers/infiniband/sw/rxe/rxe_net.c:639 [inline] rxe_net_del+0xfb/0x290 drivers/infiniband/sw/rxe/rxe_net.c:660 rxe_dellink+0x15/0x20 drivers/infiniband/sw/rxe/rxe.c:254 =20 Fixes: a60e3f3d6fba ("RDMA/nldev: Add dellink function pointer") Reported-by: syzbot+d8f76778263ab65c2b21@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=3Dd8f76778263ab65c2b21 Tested-by: syzbot+d8f76778263ab65c2b21@syzkaller.appspotmail.com Signed-off-by: Edward Adam Davis Reviewed-by: Zhu Yanjun --- drivers/infiniband/core/nldev.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/infiniband/core/nldev.c b/drivers/infiniband/core/nlde= v.c index 96c745d5bac4..3cb3cb7629fe 100644 --- a/drivers/infiniband/core/nldev.c +++ b/drivers/infiniband/core/nldev.c @@ -1816,6 +1816,8 @@ static int nldev_newlink(struct sk_buff *skb, struct = nlmsghdr *nlh, return err; } =20 +static DEFINE_MUTEX(nldev_dellink_mutex); + static int nldev_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { @@ -1846,7 +1848,9 @@ static int nldev_dellink(struct sk_buff *skb, struct = nlmsghdr *nlh, * implicitly scoped to the driver supporting dynamic link deletion like = RXE. */ if (device->link_ops && device->link_ops->dellink) { + mutex_lock(&nldev_dellink_mutex); err =3D device->link_ops->dellink(device); + mutex_unlock(&nldev_dellink_mutex); if (err) return err; } --=20 2.43.0