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 8347A312837 for ; Wed, 24 Jun 2026 16:35:09 +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=1782318910; cv=none; b=Lj8xMHfmEGNzr7aRE8nYjH607nQLTMYn0nspJWmbbnDHx1RHpz0rCi7Q0dsul324WIEp0+iiwRINdNMv6ZypTDb/tNRusHl8+i1JmeMHwPbvMhcb3/HSOQAdLxPbfPMa1f4UdlOR441hIZy69RKQlwWRIC34x8vZKXMHQSGFROs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782318910; c=relaxed/simple; bh=dBn31cCRT523d9h+8FyMQjJ+LPXzZlsMI7YAIw1w/ec=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Aady/DZi+zO0wOHp1AeF1nPla/7fYIKtt+z/fQ4M132QSKjdeW5Gdr63nzEZHCWXFo6ztZY6uIHPHV00VcbNBa/5/5syh9v2tiGELLtONlqMgwX7W4xCXc8gB+cqARcxuCVO57Ob1sTBjZNlqUjpBZaDuepTCnOBBCPp9KZohYY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=DYUEKkvl; 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="DYUEKkvl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C9AA81F000E9; Wed, 24 Jun 2026 16:35:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1782318909; bh=fzZTTv2bzAUhCSZgKSTqXVO/zf8u+Ohn4UKKaDHG4Po=; h=From:To:Cc:Subject:Date:Reply-To; b=DYUEKkvlJqqonYiWoRp4vKzZWwwUuF1SSN3ygyRSwWymJ3u3eUL2QRDBTwkkWA7PE GrZa0exuF0sCwU2O7lQf+2GHNb9MRusgSeVVWTqYU9CjR0BTJJJQLjfk5Weu+301Ra kACJ5qeO0ydVne4F8QvR75NOaN0+NAqsuKnFhZR0= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-53013: macvlan: fix macvlan_get_size() not reserving space for IFLA_MACVLAN_BC_CUTOFF Date: Wed, 24 Jun 2026 17:30:37 +0100 Message-ID: <2026062450-CVE-2026-53013-b62d@gregkh> X-Mailer: git-send-email 2.54.0 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=3409; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=sE4oPZDu6y+WOa2k+XbVaByi5zyR4iBgv+ANf58713k=; b=owGbwMvMwCRo6H6F97bub03G02pJDFk2rP9M/LX7fR1XiO+8t3LxhgvrGi4xB86xVKifGr1p6 7PDX+Ond8SyMAgyMciKKbJ82cZzdH/FIUUvQ9vTMHNYmUCGMHBxCsBE3moyLNi2ZkKpsZlUkaE+ p3yIAe+5118UixjmGQdlVVdvNN/WK7vnI/vZZVOqdn89DwA= 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: macvlan: fix macvlan_get_size() not reserving space for IFLA_MACVLAN_BC_CUTOFF macvlan_get_size() does not account for IFLA_MACVLAN_BC_CUTOFF, but macvlan_fill_info() conditionally includes it when port->bc_cutoff != 1. This causes nla_put_s32() to fail with -EMSGSIZE when the netlink skb runs out of space, triggering a WARN_ON in rtnetlink and preventing the interface from being dumped. The bug can be reproduced with: ip link add macvlan0 link eth0 type macvlan mode bridge ip link set macvlan0 type macvlan bc_cutoff 0 ip -d link show macvlan0 # fails with -EMSGSIZE The bc_cutoff feature was added in commit 954d1fa1ac93 ("macvlan: Add netlink attribute for broadcast cutoff"), which added the nla_put_s32() call in macvlan_fill_info() but missed adding the corresponding nla_total_size(4) in macvlan_get_size(). A follow-up commit 55cef78c244d ("macvlan: add forgotten nla_policy for IFLA_MACVLAN_BC_CUTOFF") fixed the missing nla_policy entry but still did not fix the size calculation. The Linux kernel CVE team has assigned CVE-2026-53013 to this issue. Affected and fixed versions =========================== Issue introduced in 6.4 with commit 954d1fa1ac93aa8a66f7d9a9ba545cf7f020d348 and fixed in 6.6.141 with commit 4979252758387b338ca968ba7e0515b0ae2257e3 Issue introduced in 6.4 with commit 954d1fa1ac93aa8a66f7d9a9ba545cf7f020d348 and fixed in 6.12.91 with commit 77ecfa4e27f282d224215895ddfbeb916fc75e24 Issue introduced in 6.4 with commit 954d1fa1ac93aa8a66f7d9a9ba545cf7f020d348 and fixed in 6.18.33 with commit b6b7154e9f5d75b608ceb2d05b376de8c638c40e Issue introduced in 6.4 with commit 954d1fa1ac93aa8a66f7d9a9ba545cf7f020d348 and fixed in 7.0.10 with commit 1c004f14ccdc11585625c168bb9a7c5e1b8afb0c Issue introduced in 6.4 with commit 954d1fa1ac93aa8a66f7d9a9ba545cf7f020d348 and fixed in 7.1 with commit fa92a77b0ed4d5f11a71665a232ac5a54a4b055d 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-2026-53013 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: drivers/net/macvlan.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/4979252758387b338ca968ba7e0515b0ae2257e3 https://git.kernel.org/stable/c/77ecfa4e27f282d224215895ddfbeb916fc75e24 https://git.kernel.org/stable/c/b6b7154e9f5d75b608ceb2d05b376de8c638c40e https://git.kernel.org/stable/c/1c004f14ccdc11585625c168bb9a7c5e1b8afb0c https://git.kernel.org/stable/c/fa92a77b0ed4d5f11a71665a232ac5a54a4b055d