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 9CE833921D8 for ; Sun, 19 Jul 2026 12:04:23 +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=1784462664; cv=none; b=SZyrHRsPgyT+0X+yucage4pP0YAvycP1q4T3H82DWwkmbSBmonRczuA8gn9kxDbp48+bcEhbAz1lx7Lrfdgn9Y53tWO+jRDsSLXMB4yIf/GguNp/kxhqt1UJFdQEpjeOg1ZUXJQg9EOuKZ2JBz1Bx6OoUp/ElPyKXqtLK9jKibY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784462664; c=relaxed/simple; bh=OT4gPgaUl1T6CGS0jvnbMKraBX49YC4c1oyY6plS2E4=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=s89s4JrdN4SEEgvUeZTOT4JOFov5zBAZBXC21lhMQEq488WjfLxNbAgnCaspmO/btNKxlAaboK0WvcNMEI1KCYwDhf9WrlTWusTNZ1fMMYo9UNvyO61hyKnf1GY7zfQdPUnphSEZku5EWdafxNELyJBhI9sc/gLpDz2mQcLXnK8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=fTFsvfL1; 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="fTFsvfL1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0D14F1F000E9; Sun, 19 Jul 2026 12:04:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784462663; bh=MbRkAhcPG91ZWbMi3oKxdd/1+uQpqQWI1RA53fwgTUY=; h=From:To:Cc:Subject:Date:Reply-To; b=fTFsvfL1a5g0KUxcfsLGGcuqKG4fneWck+htNzh2tNaEqYeDEQxsoOzd9u4Qd6KPe 76puBwxvj3w0wgpYVy159gNgT0WjzCeT6WyyQAKbEI4deVZCjbIyPiJCFxfucpMr6U ot7ej8j/k8eiRbQOY/nABf+XgUaEuH5/MqBJNgO8= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-63831: mac802154: llsec: add skb_cow_data() before in-place crypto Date: Sun, 19 Jul 2026 14:02:48 +0200 Message-ID: <2026071908-CVE-2026-63831-36ca@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=5010; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=c2bxDuignUFYDQAGJCVD6Q7gfwJPJBBEjp6/0Xq/WwQ=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkxew70/TWv/O61eGv9ptSLebaS57eHza9cJeTukLJ89 g7VQxekO2JZGASZGGTFFFm+bOM5ur/ikKKXoe1pmDmsTCBDGLg4BWAi4eYMCxoShZiePVuyIrLv Ud/CV/mahv7M8xgW7DfrvHhtwsF1drqNu9giDi5yKr68EAA= 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: mac802154: llsec: add skb_cow_data() before in-place crypto llsec_do_encrypt_unauth(), llsec_do_encrypt_auth(), llsec_do_decrypt_unauth(), and llsec_do_decrypt_auth() all perform in-place cryptographic transformations on skb data. They build a scatterlist with sg_init_one() pointing into the skb's linear data area and then pass the same scatterlist as both src and dst to the crypto API (e.g. crypto_skcipher_encrypt/decrypt, crypto_aead_encrypt/decrypt). On the RX path, __ieee802154_rx_handle_packet() clones the received skb before handing it to each subscriber via ieee802154_subif_frame(). The cloned skb shares the same underlying data buffer via reference counting. When llsec_do_decrypt() subsequently modifies this shared buffer in place, it corrupts data that other clones -- potentially belonging to other sockets or subsystems -- still reference. On the TX path, similar data sharing can occur when an skb's head has been cloned (skb_cloned() returns true). The fix is to call skb_cow_data() before performing any in-place crypto operation. skb_cow_data() ensures that the skb's data area is not shared: if the skb head is cloned or the data spans multiple fragments, it copies the data into a private buffer that can be safely modified in place. This is the same pattern used by: - ESP (net/ipv4/esp4.c, net/ipv6/esp6.c) - MACsec (drivers/net/macsec.c) - WireGuard (drivers/net/wireguard/receive.c) - TIPC (net/tipc/crypto.c) Without this guard, in-place crypto on shared skb data leads to: - Silent data corruption of other skb clones - Use-after-free when the crypto API scatterwalk writes through a page that has already been freed by another clone's kfree_skb() - Kernel crashes under concurrent 802.15.4 traffic with security enabled (KASAN/KMSAN reports slab-use-after-free) Found by 0sec (https://0sec.ai) using automated source analysis. The Linux kernel CVE team has assigned CVE-2026-63831 to this issue. Affected and fixed versions =========================== Issue introduced in 3.16 with commit 03556e4d0dbbbf4af9df76f4a3839c86f6afb015 and fixed in 5.10.260 with commit 3a2b378b3a9ca75d3518d879148d2ad25b5714a9 Issue introduced in 3.16 with commit 03556e4d0dbbbf4af9df76f4a3839c86f6afb015 and fixed in 5.15.211 with commit 7a831bcd0486788283ef35e396d4282ee01bb0d5 Issue introduced in 3.16 with commit 03556e4d0dbbbf4af9df76f4a3839c86f6afb015 and fixed in 6.1.177 with commit ff976ef7c39199ebff33c18034636595016db9f0 Issue introduced in 3.16 with commit 03556e4d0dbbbf4af9df76f4a3839c86f6afb015 and fixed in 6.6.144 with commit e28e7fd34c449028325322a3f5127b92594b7396 Issue introduced in 3.16 with commit 03556e4d0dbbbf4af9df76f4a3839c86f6afb015 and fixed in 6.12.95 with commit 993fd674fe85d114e6a8d3963033d4fbbc2170a8 Issue introduced in 3.16 with commit 03556e4d0dbbbf4af9df76f4a3839c86f6afb015 and fixed in 6.18.38 with commit bd968bdd568beacfdf98ec537a87527e85f1d0cf Issue introduced in 3.16 with commit 03556e4d0dbbbf4af9df76f4a3839c86f6afb015 and fixed in 7.1.3 with commit 86d531337ea1ba02d9f2bc830d07c683d9bfaade Issue introduced in 3.16 with commit 03556e4d0dbbbf4af9df76f4a3839c86f6afb015 and fixed in 7.2-rc1 with commit 84a04eb5b210643bd67aab81ff805d32f62aa865 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-2026-63831 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/mac802154/llsec.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/3a2b378b3a9ca75d3518d879148d2ad25b5714a9 https://git.kernel.org/stable/c/7a831bcd0486788283ef35e396d4282ee01bb0d5 https://git.kernel.org/stable/c/ff976ef7c39199ebff33c18034636595016db9f0 https://git.kernel.org/stable/c/e28e7fd34c449028325322a3f5127b92594b7396 https://git.kernel.org/stable/c/993fd674fe85d114e6a8d3963033d4fbbc2170a8 https://git.kernel.org/stable/c/bd968bdd568beacfdf98ec537a87527e85f1d0cf https://git.kernel.org/stable/c/86d531337ea1ba02d9f2bc830d07c683d9bfaade https://git.kernel.org/stable/c/84a04eb5b210643bd67aab81ff805d32f62aa865