From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f73.google.com (mail-pj1-f73.google.com [209.85.216.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 45273262FF8 for ; Fri, 4 Jul 2025 06:53:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751612038; cv=none; b=WMDr7VlnTBdQAzPaW4RmfjsNmuHtwAFPpAhtGBTTGFX5jH944WctVaWgFTaSJBgeN5vZ711On6e3VGJPgnmUqxvvaIvi/mc7SsmF5rwDuR+CJAMZKlVyWxD5PCbwzugKaif1iC2DNq1nuzS2RLDg6sEJGrAgX/URMKPY2mgInYw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751612038; c=relaxed/simple; bh=ZD5Oi6qfqSghs5blXGjF4/A2SjG+R6HZdKn1z5H40pk=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=cCrqNaxizgomcdFv+RCEcKA0uuqFotZ65eoyqaG+9frrIbVgJxre6rQALbIu7x3mkkNtp5N5DpdI5hvl7I3BmTmohIz0Ns3BXTr1zu9GNbop3Bh0gVxipWv6CxVeAw5heRZXiVzdBqyerSNY9/ieX+nBYLqJ0mECBB0OKpktWmI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--kuniyu.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=WiuNgRJV; arc=none smtp.client-ip=209.85.216.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--kuniyu.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="WiuNgRJV" Received: by mail-pj1-f73.google.com with SMTP id 98e67ed59e1d1-31327b2f8e4so742819a91.1 for ; Thu, 03 Jul 2025 23:53:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1751612036; x=1752216836; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=W8NlYxsq0UhxD+/G2U/ObTmc+kAFGm4jak2J5JnfGBg=; b=WiuNgRJVaeNaC5gxPadvgVlNdtzE6Yrj9dVsdT8v2QtorzeJ/KWTKsJPr/bjN4WjJS apLzmxDjnUTGbCvrjg12wr8j8HBn5VYmIMHfuB5cfHTn2VMmq9U+Mx8MfxHdlTD483/A NLf1VrjB0gxPHscEbXMsNKyv7J/qmosCzNPndK/uEL+UapyrTWVDKBeTmQb65mQn93NE zaFbRZFmEcw6nwARwEDOVywz/2XH79w1BSMQDm6EV1lAbnjzjeRm7NHjrc6EN6CVaRVZ 20q4DOH9PHvrVd+/YqEJ7RssETjhYM4ZOgMvwyOeKriZ203lPJXUo7DWyXKdIb069xxT z/zQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1751612036; x=1752216836; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=W8NlYxsq0UhxD+/G2U/ObTmc+kAFGm4jak2J5JnfGBg=; b=PaHMtqTmeHQcHVqjo95Kc4CC8k/tNR8Le8UKgikE4Ldhb9nDUTP5m3fnB6OTsWvd8t 8aJXehr4TC2GKAuFYxujXI2CEWjg/9oT+YCfcjjC3OCZajgRMYCPsLzP5S6i7/oEB1Fp YC5z20PIqE+m90YTPLdGby0N2TqSI13tC8XhdclZgRu45qzDQHN+nUSV4q/3uIPZnOCi ewBoS2Q1NjTWYTt3RbtH4pnhQyMkEn4bED3ZFX8OkhjJTvhNupi9687rSeiUryBdkN27 Z4tDoHZHVvEWCin7dPoSfORwRvXpF9BL8FEJ3lq27hfwhO5e28c9eI8ikY8IMER6X1zm JuVQ== X-Forwarded-Encrypted: i=1; AJvYcCWCj35NOk2QtAjbYZsPp3Mn6LBBWMmevYWtOTTACoRC2NeV8iLbQOrwj7+WRZoknOzHFQZ3R/0hpnVVpX8=@vger.kernel.org X-Gm-Message-State: AOJu0YzRp5tiemcdH4sc/U+N1dOOtvLCOFTtS+kxW7u+N1Y+ZLJobS74 PoH1Nli3P0XTjT4aOoSHdZzdFSlrngbqUD6Cia66Mr1ciRVP7q2570IbXEieAPekMk+zRQ7PKPh QF5fNAg== X-Google-Smtp-Source: AGHT+IGuqBbpZrVlluSjRLfeBqi/+KnCRXr3Q0QAtP/brFRAfKpBGbJmlzfPjWo0VyJZBVCaDo6HkSa9e/g= X-Received: from pjbsw11.prod.google.com ([2002:a17:90b:2c8b:b0:311:ef56:7694]) (user=kuniyu job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:3d4c:b0:315:fefe:bebf with SMTP id 98e67ed59e1d1-31aac44bb7amr2511921a91.13.1751612036618; Thu, 03 Jul 2025 23:53:56 -0700 (PDT) Date: Fri, 4 Jul 2025 06:53:38 +0000 In-Reply-To: <20250704023914.3876975-1-yuehaibing@huawei.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250704023914.3876975-1-yuehaibing@huawei.com> X-Mailer: git-send-email 2.50.0.727.gbf7dc18ff4-goog Message-ID: <20250704065353.1621693-1-kuniyu@google.com> Subject: Re: [PATCH] atm: clip: Fix NULL pointer dereference in vcc_sendmsg() From: Kuniyuki Iwashima To: yuehaibing@huawei.com Cc: davem@davemloft.net, edumazet@google.com, horms@kernel.org, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, kuniyu@google.com Content-Type: text/plain; charset="UTF-8" Please specify 'net' in subject: [PATCH net v2] atm: clip: ... From: Yue Haibing Date: Fri, 4 Jul 2025 10:39:14 +0800 > 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-00346-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. Please move commit message before the splat. > > 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@google.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); > } > > +static int atmarpd_send(struct atm_vcc *vcc, struct sk_buff *skb) > +{ > + dev_kfree_skb_any(skb); This is not enough, see: commit 7851263998d4269125fd6cb3fdbfc7c6db853859 Author: Kuniyuki Iwashima Date: Mon Jun 16 18:21:15 2025 atm: Revert atm_account_tx() if copy_from_iter_full() fails. > + return 0; > +} > + > static const struct atmdev_ops atmarpd_dev_ops = { > - .close = atmarpd_close > + .close = atmarpd_close, > + .send = atmarpd_send > }; > > > -- > 2.34.1