From nobody Wed Oct 8 00:28:02 2025 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) (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 DCCC8262A6; Fri, 4 Jul 2025 02:26:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.188 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751596014; cv=none; b=VleraLPxHsE0BTAjzP1U/nuZ7LRorJvp5IVKLsB7HIPwJ9qC3cinFEq9y5FNFfdQ77ogAsRqosxKEZ9JwMQJrVLqQr1WOaXcEnkmZdzzXJtlfT7d9aC4aAu3kYDkh25ecKld5VbyeewKv8uMm5O3NcNkVERbm/fvcboWp+j0edw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751596014; c=relaxed/simple; bh=2Jvgtj5t3hZ5VQ36euT0z9PS2vO0mdNlfh7YaTvGcyc=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=Ys5hxJeFTk4hdBQJneEAhKSMWvPJh8l4PWMRP3PqiMQjMA5TchLy1Rhc0noJSoZtrBJVFVhvodcxeIyYpwy+r9BESh/ju2Arx1UqN6a+yRO9ULAao4hHLLfxyj1kPA6AFp1iNFzN1iGKBOq8H5+DegcmT0Ta2XmkbsoauUH/+vk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.188 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.163.252]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4bYHYJ40KDzVmcW; Fri, 4 Jul 2025 10:25:40 +0800 (CST) Received: from dggpemf500002.china.huawei.com (unknown [7.185.36.57]) by mail.maildlp.com (Postfix) with ESMTPS id 17713180B2C; Fri, 4 Jul 2025 10:26:48 +0800 (CST) Received: from huawei.com (10.175.124.27) by dggpemf500002.china.huawei.com (7.185.36.57) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Fri, 4 Jul 2025 10:26:47 +0800 From: Yue Haibing To: , , , , CC: , , Subject: [PATCH] atm: clip: Fix NULL pointer dereference in vcc_sendmsg() Date: Fri, 4 Jul 2025 10:39:14 +0800 Message-ID: <20250704023914.3876975-1-yuehaibing@huawei.com> X-Mailer: git-send-email 2.34.1 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 X-ClientProxiedBy: kwepems100002.china.huawei.com (7.221.188.206) To dggpemf500002.china.huawei.com (7.185.36.57) Content-Type: text/plain; charset="utf-8" BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 0 P4D 0 Oops: Oops: 0010 [#1] SMP KASAN NOPTI CPU: 0 UID: 0 PID: 5324 Comm: syz.0.0 Not tainted 6.15.0-rc6-syzkaller-0034= 6-g5723cc3450bc #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16= .3-2~bpo12+1 04/01/2014 RIP: 0010:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0018:ffffc9000d3cf778 EFLAGS: 00010246 RAX: 1ffffffff1910dd1 RBX: 00000000000000c0 RCX: dffffc0000000000 RDX: ffffc9000dc82000 RSI: ffff88803e4c4640 RDI: ffff888052cd0000 RBP: ffffc9000d3cf8d0 R08: ffff888052c9143f R09: 1ffff1100a592287 R10: dffffc0000000000 R11: 0000000000000000 R12: 1ffff92001a79f00 R13: ffff888052cd0000 R14: ffff88803e4c4640 R15: ffffffff8c886e88 FS: 00007fbc762566c0(0000) GS:ffff88808d6c2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 0000000041f1b000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vcc_sendmsg+0xa10/0xc50 net/atm/common.c:644 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 ____sys_sendmsg+0x52d/0x830 net/socket.c:2566 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620 __sys_sendmmsg+0x227/0x430 net/socket.c:2709 __do_sys_sendmmsg net/socket.c:2736 [inline] __se_sys_sendmmsg net/socket.c:2733 [inline] __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2733 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f atmarpd_dev_ops does not implement the send method, which may cause crash as above. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+e34e5e6b5eddb0014def@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/682f82d5.a70a0220.1765ec.0143.GAE@googl= e.com/T Signed-off-by: Yue Haibing --- net/atm/clip.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/net/atm/clip.c b/net/atm/clip.c index b234dc3bcb0d..c02ba9d64bc3 100644 --- a/net/atm/clip.c +++ b/net/atm/clip.c @@ -616,8 +616,15 @@ static void atmarpd_close(struct atm_vcc *vcc) module_put(THIS_MODULE); } =20 +static int atmarpd_send(struct atm_vcc *vcc, struct sk_buff *skb) +{ + dev_kfree_skb_any(skb); + return 0; +} + static const struct atmdev_ops atmarpd_dev_ops =3D { - .close =3D atmarpd_close + .close =3D atmarpd_close, + .send =3D atmarpd_send }; =20 =20 --=20 2.34.1