From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 BAFB336C9F9 for ; Sat, 28 Feb 2026 18:13:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302386; cv=none; b=FBO+CssDHdPrKFh6mh9iLG7sR3p1PnpOqrQZ0SKXWKGBAZ3X3rWQ0GaIuXN/LhTxB7hHel/oNayu06TCrOg9f5jwtDzQqxLGsJJyvYNSqaJZC5uoeQiPacNSkU6KEp7ZSC3xlx7+uRpcYtJer6WkamVLw9OKZv9LAMNDtuxadXE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302386; c=relaxed/simple; bh=2ND13i84SypvNRbZZrQfr+MlM4RAq7zcw70kQ34VkYI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=P9j/w4Xs20sVAIINE8Qx2m4+0gtnW8ROKXzXmx9xJAIaNPfeSaIexY2yUgQbmda45iF/UNnC7hwaZdV6tgCqUK50ORnmDoSkHWmfX+3XLdM8Olb2tb38uKGolSol2ln07EfXJgxGW6VMQz55y1eq2VfajbLSKDaGE4rVw1QKZis= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=GxvoH4AH; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="GxvoH4AH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E6DDC19423; Sat, 28 Feb 2026 18:13:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772302386; bh=2ND13i84SypvNRbZZrQfr+MlM4RAq7zcw70kQ34VkYI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GxvoH4AHmR3GNtI8SSRFfEj9VgvYwlW98GJtanuIWecB141cbaN+MR8fxanUBJhLx 5oU+iexTTLQkX0UgEUiRwHwPeMXolumTWkscxAHwoy3pSYuahNies0IKhR8bt4igdH OU+aC/uDHuhCoHaWUr1KdLczoo9hQJxbeMJo4M5bwM5K3C2JHs9glg3D3Y7ShYmUz7 EUA8xhjQ/ZkwLZlZ6hqkMBZBSK5hQk+Y2WBtYp22MKL3l8AoX8/HZ2UmhBCVzn88VM 8hR23TtsBtFcs23wohTR79UQqqxUSzGshbl289KnYbq8rLUq6Y0KHi+bFmIe4nrvvF TdkZJjGQp2HeA== From: Sasha Levin To: patches@lists.linux.dev Cc: Votokina Victoria , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1 115/232] nfc: hci: shdlc: Stop timers and work before freeing context Date: Sat, 28 Feb 2026 13:09:28 -0500 Message-ID: <20260228181127.1592657-115-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228181127.1592657-1-sashal@kernel.org> References: <20260228181127.1592657-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Votokina Victoria [ Upstream commit c9efde1e537baed7648a94022b43836a348a074f ] llc_shdlc_deinit() purges SHDLC skb queues and frees the llc_shdlc structure while its timers and state machine work may still be active. Timer callbacks can schedule sm_work, and sm_work accesses SHDLC state and the skb queues. If teardown happens in parallel with a queued/running work item, it can lead to UAF and other shutdown races. Stop all SHDLC timers and cancel sm_work synchronously before purging the queues and freeing the context. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 4a61cd6687fc ("NFC: Add an shdlc llc module to llc core") Signed-off-by: Votokina Victoria Link: https://patch.msgid.link/20260203113158.2008723-1-Victoria.Votokina@kaspersky.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/nfc/hci/llc_shdlc.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/net/nfc/hci/llc_shdlc.c b/net/nfc/hci/llc_shdlc.c index e90f70385813a..a106f4352356d 100644 --- a/net/nfc/hci/llc_shdlc.c +++ b/net/nfc/hci/llc_shdlc.c @@ -762,6 +762,14 @@ static void llc_shdlc_deinit(struct nfc_llc *llc) { struct llc_shdlc *shdlc = nfc_llc_get_data(llc); + timer_shutdown_sync(&shdlc->connect_timer); + timer_shutdown_sync(&shdlc->t1_timer); + timer_shutdown_sync(&shdlc->t2_timer); + shdlc->t1_active = false; + shdlc->t2_active = false; + + cancel_work_sync(&shdlc->sm_work); + skb_queue_purge(&shdlc->rcv_q); skb_queue_purge(&shdlc->send_q); skb_queue_purge(&shdlc->ack_pending_q); -- 2.51.0