From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 7758E34D397 for ; Sat, 22 Aug 2026 15:34:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787412871; cv=none; b=mmrnRCMofSXyLULtwviBwTw/foEnQCcZuiiZkWIcPMU8eJNR46Z7gZlISeMQyHU0BS3jLlvnDMKuEFnEsqgdUasvF08+Z1bAL/mt/7hiOZLoiRSgxHzhI6VIg1pZss624uJ+z3W0Y1mb8zsNSC9YHUSywdNFMsvMKibk8t8+c4g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787412871; c=relaxed/simple; bh=gTDGxvoo9wQfVTQ5Z8tJayK417OqzBDI6TMY7/oR2Rw=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=WEvEC++JZZ4sSqu5qWjxfN82u+M4aqJ2xNRNxz/gj2IfKwCgs4mPAY3OK24Mb+xo4HM+KeW03h88qbc7bIOIf4c/xYCAxfncYBCkAai2YEnfeJUzqbpoiwQvaE/qeD0zK3y3B2u8CwRMFx1MaUPgTILUWaZ3uBx+i5bCFA9Sw1c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=xechC7I6; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="xechC7I6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CBBC91F000E9; Sat, 22 Aug 2026 15:34:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787412869; bh=MQYiu/kVtlNlM5QdjDuq77RttCSt2Pp007csqhguvD4=; h=From:To:Cc:Subject:Date:Reply-To; b=xechC7I6Gp2DOALvlxqdsV1X8X3vqG+SavxhUJWoBY0wQ7b0V3efPQ0/pzN/8/vRr 5YOLxCLUQxLyL3mKlZ70R7cuYqzt7SDp6LHbkzzZL9K+sJABcVbTmV7JBoSXxhn0l6 wu+a4bxN/K5zp7uEIH04ehiaZeyBUDzfJg5aPyjk= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-74611: tls: rx: restore msg_iter before TLS 1.3 optimistic retry Date: Sat, 22 Aug 2026 17:31:35 +0200 Message-ID: <2026082217-CVE-2026-74611-1af7@gregkh> X-Mailer: git-send-email 2.55.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2811; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=eSxARxwit1+t+9sqXsSvKihbHu+tqHDa2g2wgtWBKNQ=; b=owGbwMvMwCRo6H6F97bub03G02pJDFmdB46WP6+zZEvLjLr0dOkWa95lH8UCpzGcs1v7TitfY ccX497nHbEsDIJMDLJiiixftvEc3V9xSNHL0PY0zBxWJpAhDFycAjARyQsMc6WZstKWfF9Vv69e 99gGnmbXvw5qCxlmsx7MPP1YqDwwIv6d/0MRoc+n5OqNAQ== X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: tls: rx: restore msg_iter before TLS 1.3 optimistic retry tls_decrypt_sg() advances msg->msg_iter when it maps user pages for the optimistic TLS 1.3 zero-copy path. If the decrypted record turns out not to be unpadded application data, tls_decrypt_sw() retries into a kernel skb, but leaves the iterator advanced. The subsequent copy from the skb then writes decrypted bytes again at a later point in the caller iovecs while recvmsg() reports only the post-retry length. A TLS peer can trigger this after the receiver enables TLS_RX_EXPECT_NO_PAD. Revert the iterator by the number of bytes consumed by the optimistic mapping before retrying without zero-copy. Add a selftest which sends a TLS 1.3 control record with TLS_RX_EXPECT_NO_PAD enabled and verifies that recvmsg() does not overwrite later iovecs beyond the returned length. The Linux kernel CVE team has assigned CVE-2026-74611 to this issue. Affected and fixed versions =========================== Issue introduced in 6.0 with commit ce61327ce989b63c0bd1cc7afee00e218ee696ac and fixed in 6.18.45 with commit 68787940274ec89f41dc91b1a68ee1a16a90735f Issue introduced in 6.0 with commit ce61327ce989b63c0bd1cc7afee00e218ee696ac and fixed in 7.1.9 with commit 3c837266a734e2a22b24d2d567404a501d405835 Issue introduced in 6.0 with commit ce61327ce989b63c0bd1cc7afee00e218ee696ac and fixed in 7.2 with commit 1c8629651cb54f7b51db8fc0b1a9944e4a4b0f5e Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-74611 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: net/tls/tls_sw.c tools/testing/selftests/net/tls.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/68787940274ec89f41dc91b1a68ee1a16a90735f https://git.kernel.org/stable/c/3c837266a734e2a22b24d2d567404a501d405835 https://git.kernel.org/stable/c/1c8629651cb54f7b51db8fc0b1a9944e4a4b0f5e