From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from azure-sdnproxy.icoremail.net (azure-sdnproxy.icoremail.net [13.75.44.102]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 234F73FE669 for ; Fri, 8 May 2026 15:58:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.75.44.102 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778255932; cv=none; b=eZWMgZFmHL06gzBjZfpnp/DyurZv/4NeMHS3HJOLq1T8E+Gzl9oMq+9+ALj0lWBBuOP+ZBj2SVjstljJP6YsUp/GR6xNP3qKIIvPvjma/cHxlNji8t6BD96M+9zLLCb8GgSAkK67bi2+bTuyN2645i521Ktr1uxj3rMuNVVQD4E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778255932; c=relaxed/simple; bh=nck0kZqjMkMaMsNTUP0Bx8WarBnSNZnz+rfVXMAaHpA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WH4lbvV9KxmPRQPJ7NJAZlljyhGCL5lfwqoLkGLzID6wUR3w+moHNjoHuSl/u0KT1CJGKYrbdF22RU8WYMwJMSpgXuMS/64l41NcDXkvlIkFoCqqguXFuj4iYD+EFZnJc9j9BVBWeUViCdWFMmNT8pzcZfv9lPCWDWQziLq2ZP0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=lzu.edu.cn; spf=pass smtp.mailfrom=lzu.edu.cn; arc=none smtp.client-ip=13.75.44.102 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=lzu.edu.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lzu.edu.cn Received: from enjou-Legion-Y7000P-2019.coin-barley.ts.net (unknown [172.23.56.36]) by app1 (Coremail) with SMTP id ygmowADXRfYoCP5pHIP+AA--.2636S3; Fri, 08 May 2026 23:58:35 +0800 (CST) From: Ren Wei To: linux-afs@lists.infradead.org, netdev@vger.kernel.org Cc: dhowells@redhat.com, marc.dionne@auristor.com, yuantan098@gmail.com, yifanwucs@gmail.com, tomapufckgml@gmail.com, bird@lzu.edu.cn, d4n.for.sec@gmail.com, n05ec@lzu.edu.cn Subject: [PATCH net 1/1] rxrpc: serialize kernel accept preallocation with socket teardown Date: Fri, 8 May 2026 23:58:28 +0800 Message-ID: <4e9e2d92be94ed4bcb43b70b36fcc3863414d61e.1778230563.git.d4n.for.sec@gmail.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID:ygmowADXRfYoCP5pHIP+AA--.2636S3 X-Coremail-Antispam: 1UD129KBjvJXoW7ArykWrW3GFyDCF4kWry3urg_yoW8try8pF WfGw1ftrWkXr1fuFnaqr40grW5Wa18Jr1UJ397Z3ZYkrn29a4aqry8tay2vr15Z3s5GrW3 Ar1qka4v9w4xZFDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBj1xkIjI8I6I8E6xAIw20EY4v20xvaj40_Wr0E3s1l1IIY67AE w4v_Jr0_Jr4l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2 IY67AKxVW8JVW5JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwA2z4x0Y4vEx4A2 jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq3wAS0I0E0xvYzxvE52 x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWU GwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI4 8JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2kIc2xKxwCY1x0262kK e7AKxVWUtVW8ZwCY02Avz4vE-syl42xK82IYc2Ij64vIr41l42xK82IY6x8ErcxFaVAv8V W8GwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480 Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7 IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k2 6cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxV AFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUd-B_UUUUU= X-CM-SenderInfo: zqqvvuo6o23hxhgxhubq/1tbiAQEBCWn9o2QIWgAAsJ From: Li Daming rxrpc_kernel_charge_accept() reads rx->backlog without any socket/backlog synchronization and passes that raw pointer into rxrpc_service_prealloc_one(). A concurrent rxrpc_discard_prealloc() sets rx->backlog = NULL and frees the backlog rings, so a kernel preallocation worker can keep using a freed struct rxrpc_backlog while updating *_backlog_head/tail and array slots. Serialize the state check and backlog lookup with the socket lock, and reject kernel preallocation once teardown has disabled listening or discarded the service backlog. Fixes: 00e907127e6f ("rxrpc: Preallocate peers, conns and calls for incoming service requests") Cc: stable@kernel.org Reported-by: Yuan Tan Reported-by: Yifan Wu Reported-by: Juefei Pu Reported-by: Xin Liu Signed-off-by: Li Daming Signed-off-by: Ren Wei --- net/rxrpc/call_accept.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) diff --git a/net/rxrpc/call_accept.c b/net/rxrpc/call_accept.c index ee2d131..4782412 100644 --- a/net/rxrpc/call_accept.c +++ b/net/rxrpc/call_accept.c @@ -471,13 +471,26 @@ int rxrpc_kernel_charge_accept(struct socket *sock, rxrpc_notify_rx_t notify_rx, unsigned long user_call_ID, gfp_t gfp, unsigned int debug_id) { - struct rxrpc_sock *rx = rxrpc_sk(sock->sk); - struct rxrpc_backlog *b = rx->backlog; + struct rxrpc_backlog *b; + struct rxrpc_sock *rx; + struct sock *sk; + int ret; - if (sock->sk->sk_state == RXRPC_CLOSE) - return -ESHUTDOWN; + sk = sock->sk; + rx = rxrpc_sk(sk); + + lock_sock(sk); + if (sk->sk_state != RXRPC_SERVER_LISTENING || !rx->backlog) { + ret = -ESHUTDOWN; + goto out; + } + + b = rx->backlog; + ret = rxrpc_service_prealloc_one(rx, b, notify_rx, user_call_ID, + gfp, debug_id); - return rxrpc_service_prealloc_one(rx, b, notify_rx, user_call_ID, - gfp, debug_id); +out: + release_sock(sk); + return ret; } EXPORT_SYMBOL(rxrpc_kernel_charge_accept); -- 2.43.0