From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from fhigh-a6-smtp.messagingengine.com (fhigh-a6-smtp.messagingengine.com [103.168.172.157]) (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 223D82CA9 for ; Wed, 29 Jan 2025 13:12:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=103.168.172.157 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738156332; cv=none; b=XfzUknnCiNvBOfN2yykkCl820yd/GTcI7l/OL1f7AwHRqr6zat45gFZN6ZQpKephY6ZmxbN6dGJWDSMj++RAuk3pZAGkMPb3lIeaDm3byox9BLclm1U41AK/V6KHOW7huFeBmIGVt0EeJWfp2AuMDevmkZtodILqQW5anGneYWE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738156332; c=relaxed/simple; bh=gnY4et/h7DY6DDyYCoKe2Ped1jZox8dCpxxATBsJJSc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Z/AzHITSvdoXGO62bVsPVYm03vukFVWzkcU706nO25IjnQFxyLCKyMKIis1PgrsI61YESyS3XpjrMTvwT51ZeUSjbghObFIFoW+9yF5rZOWi/pgd5nOwUN4cLdMnCsFnIDjY8u23H53leffpSOLeJ13vab/sSKsjgBSoVeEYQuQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=kroah.com; spf=pass smtp.mailfrom=kroah.com; dkim=pass (2048-bit key) header.d=kroah.com header.i=@kroah.com header.b=C+EINIm2; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b=UvknCgP+; arc=none smtp.client-ip=103.168.172.157 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=kroah.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kroah.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kroah.com header.i=@kroah.com header.b="C+EINIm2"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="UvknCgP+" Received: from phl-compute-09.internal (phl-compute-09.phl.internal [10.202.2.49]) by mailfhigh.phl.internal (Postfix) with ESMTP id EB10811400FB; Wed, 29 Jan 2025 08:12:08 -0500 (EST) Received: from phl-mailfrontend-01 ([10.202.2.162]) by phl-compute-09.internal (MEProxy); Wed, 29 Jan 2025 08:12:08 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kroah.com; h=cc :cc:content-type:content-type:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:subject :subject:to:to; s=fm3; t=1738156328; x=1738242728; bh=m7SnI2oRXh brb5cbr7sSO/FzrPHKiPNZaBHYPHhV9VU=; b=C+EINIm28KQQ0tKgdzv9nnyjWg naPLtLlir4clOZs3YZNr/k+UozekiXHYd8egnyEhhzyNBxQQaJOa9IoWkvPlxFPV tBSxuoVmldwzhb/uovPB04PjNs0sA8m/lM4T45tkxQU9lbu55JLvB8Vx/DrefNo4 1KoGJ9awL3yOs4pI/5KRwqvWqhibSpKcjyrqOEBZwqngpfRuvTyQJyhJ/swgZ85/ 4PmAb8WVX6My3iJjx3yAGTYteaITV77XXmW8uWDHfdgXcNKgL1vL9OPt7ZjNIlyP BVpQadDL3FmbmKBsjEu4AyjtG3w78fmspSuf8kaAv+f3ydO5r+xFpX6MADBg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:content-type:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:subject:subject:to :to:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm3; t= 1738156328; x=1738242728; bh=m7SnI2oRXhbrb5cbr7sSO/FzrPHKiPNZaBH YPHhV9VU=; b=UvknCgP+pkQ5oDFz/HfJ/7MsO7Xd3hrSS69SdGjsYZZKfRpLmJ9 JYWx6DkJqn8Ot/ehSh/xukMP0QiNXWK6LxFYqM2KHfB+zB2Zj7poG+sMlRtQh4bR RDdj14RZUmYo+29nAGlAFav3U+kSJBqjVa8yMOuLieqI2QrcnUqF7nu4BKBNVeb5 uT5i/MUa6mnxeP7a5DvsC0rOIUCZESivBbnyYm2ePeol0zCmvn5re1K4EJdix0/g vyEQA0VXgVSDrqfFrEAMxZ/y3CEbYYkCGiY0BBNnoggArfjyCxZkoBxDFO6Rz11n euEX0vTMbXrlErnE/1hFqMgwaGfdTOTasKg== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgdeftdekucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdggtfgfnhhsuhgsshgtrhhisggvpdfu rfetoffkrfgpnffqhgenuceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnh htshculddquddttddmnecujfgurhepfffhvfevuffkfhggtggujgesthdtredttddtvden ucfhrhhomhepifhrvghgucfmjfcuoehgrhgvgheskhhrohgrhhdrtghomheqnecuggftrf grthhtvghrnhepjeetueehteekuefhleehkeffffeiffeftedtieegkedviefggfefueff kefgueffnecuffhomhgrihhnpehmshhgihgurdhlihhnkhenucevlhhushhtvghrufhiii gvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpehgrhgvgheskhhrohgrhhdrtghomhdp nhgspghrtghpthhtohepuddtpdhmohguvgepshhmthhpohhuthdprhgtphhtthhopegrlh hvrghlrghnleesfhhogihmrghilhdrtghomhdprhgtphhtthhopehsthgrsghlvgesvhhg vghrrdhkvghrnhgvlhdrohhrghdprhgtphhtthhopeifrghnghhlihgrnhhgjeegsehhuh grfigvihdrtghomhdprhgtphhtthhopegvughumhgriigvthesghhoohhglhgvrdgtohhm pdhrtghpthhtohepkhhusggrsehkvghrnhgvlhdrohhrgh X-ME-Proxy: Feedback-ID: i787e41f1:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 29 Jan 2025 08:12:06 -0500 (EST) Date: Wed, 29 Jan 2025 10:42:57 +0100 From: Greg KH To: alvalan9@foxmail.com Cc: stable@vger.kernel.org, Wang Liang , Eric Dumazet , Jakub Kicinski Subject: Re: [PATCH 6.1.y v2] net: fix data-races around sk->sk_forward_alloc Message-ID: <2025012949-mouth-enable-e51c@gregkh> References: Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Jan 22, 2025 at 07:35:21PM +0800, alvalan9@foxmail.com wrote: > From: Wang Liang > > commit 073d89808c065ac4c672c0a613a71b27a80691cb upstream. > > Syzkaller reported this warning: > ------------[ cut here ]------------ > WARNING: CPU: 0 PID: 16 at net/ipv4/af_inet.c:156 inet_sock_destruct+0x1c5/0x1e0 > Modules linked in: > CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.12.0-rc5 #26 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 > RIP: 0010:inet_sock_destruct+0x1c5/0x1e0 > Code: 24 12 4c 89 e2 5b 48 c7 c7 98 ec bb 82 41 5c e9 d1 18 17 ff 4c 89 e6 5b 48 c7 c7 d0 ec bb 82 41 5c e9 bf 18 17 ff 0f 0b eb 83 <0f> 0b eb 97 0f 0b eb 87 0f 0b e9 68 ff ff ff 66 66 2e 0f 1f 84 00 > RSP: 0018:ffffc9000008bd90 EFLAGS: 00010206 > RAX: 0000000000000300 RBX: ffff88810b172a90 RCX: 0000000000000007 > RDX: 0000000000000002 RSI: 0000000000000300 RDI: ffff88810b172a00 > RBP: ffff88810b172a00 R08: ffff888104273c00 R09: 0000000000100007 > R10: 0000000000020000 R11: 0000000000000006 R12: ffff88810b172a00 > R13: 0000000000000004 R14: 0000000000000000 R15: ffff888237c31f78 > FS: 0000000000000000(0000) GS:ffff888237c00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007ffc63fecac8 CR3: 000000000342e000 CR4: 00000000000006f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > > ? __warn+0x88/0x130 > ? inet_sock_destruct+0x1c5/0x1e0 > ? report_bug+0x18e/0x1a0 > ? handle_bug+0x53/0x90 > ? exc_invalid_op+0x18/0x70 > ? asm_exc_invalid_op+0x1a/0x20 > ? inet_sock_destruct+0x1c5/0x1e0 > __sk_destruct+0x2a/0x200 > rcu_do_batch+0x1aa/0x530 > ? rcu_do_batch+0x13b/0x530 > rcu_core+0x159/0x2f0 > handle_softirqs+0xd3/0x2b0 > ? __pfx_smpboot_thread_fn+0x10/0x10 > run_ksoftirqd+0x25/0x30 > smpboot_thread_fn+0xdd/0x1d0 > kthread+0xd3/0x100 > ? __pfx_kthread+0x10/0x10 > ret_from_fork+0x34/0x50 > ? __pfx_kthread+0x10/0x10 > ret_from_fork_asm+0x1a/0x30 > > ---[ end trace 0000000000000000 ]--- > > Its possible that two threads call tcp_v6_do_rcv()/sk_forward_alloc_add() > concurrently when sk->sk_state == TCP_LISTEN with sk->sk_lock unlocked, > which triggers a data-race around sk->sk_forward_alloc: > tcp_v6_rcv > tcp_v6_do_rcv > skb_clone_and_charge_r > sk_rmem_schedule > __sk_mem_schedule > sk_forward_alloc_add() > skb_set_owner_r > sk_mem_charge > sk_forward_alloc_add() > __kfree_skb > skb_release_all > skb_release_head_state > sock_rfree > sk_mem_uncharge > sk_forward_alloc_add() > sk_mem_reclaim > // set local var reclaimable > __sk_mem_reclaim > sk_forward_alloc_add() > > In this syzkaller testcase, two threads call > tcp_v6_do_rcv() with skb->truesize=768, the sk_forward_alloc changes like > this: > (cpu 1) | (cpu 2) | sk_forward_alloc > ... | ... | 0 > __sk_mem_schedule() | | +4096 = 4096 > | __sk_mem_schedule() | +4096 = 8192 > sk_mem_charge() | | -768 = 7424 > | sk_mem_charge() | -768 = 6656 > ... | ... | > sk_mem_uncharge() | | +768 = 7424 > reclaimable=7424 | | > | sk_mem_uncharge() | +768 = 8192 > | reclaimable=8192 | > __sk_mem_reclaim() | | -4096 = 4096 > | __sk_mem_reclaim() | -8192 = -4096 != 0 > > The skb_clone_and_charge_r() should not be called in tcp_v6_do_rcv() when > sk->sk_state is TCP_LISTEN, it happens later in tcp_v6_syn_recv_sock(). > Fix the same issue in dccp_v6_do_rcv(). > > Suggested-by: Eric Dumazet > Reviewed-by: Eric Dumazet > Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets") > Signed-off-by: Wang Liang > Link: https://patch.msgid.link/20241107023405.889239-1-wangliang74@huawei.com > Signed-off-by: Jakub Kicinski > Signed-off-by: Alva Lan > --- > v2: For I had sent the patch two times, I added v2 to the subject to distinguish it from the v1 version. Does not apply to 6.1.y at all :(