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 06FFE352036 for ; Sat, 15 Aug 2026 06:12:27 +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=1786774348; cv=none; b=hVQmkdBtTmRgfAhuCg0U76ykfk2Q7hU++q40bBoYpJ0hue7kRterqjsd3IMk1T1VRQM2mDpvdlYg4m+gER3dCLLkAFh3qs52oxz9/vdIjUgRIGGfEn4Q4DwRKTg9t2TwAy5Y8TnzaAE/lR/wBoLokDenXW/PbK38ygvYACBFkn8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786774348; c=relaxed/simple; bh=MUEoPy3W7iREtqHw+L8dTnxKwHE/vtvBsfZH1XdXME4=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=iLUMeOVqTu2b74kTtjvvrRVnYeP1iKByczKe+Mj6b+/zZtp5dT80zqd2ZWmn7LNJ/dXrKPhgHOuINdhSxqBA8aQyemvDZlQc5B4ZfaLO0PNj628dtjHNOiToXiC1ftxRlMy84sjJ4mDFmmEXwL2uD/mcXFXs8TL/ysnV1YAEeA8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Vfljycdt; 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="Vfljycdt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5F59F1F000E9; Sat, 15 Aug 2026 06:12:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786774346; bh=LGfofyt1Ew5do8jczsSOEap9Z7/gKm3vwziL76C+T5A=; h=From:To:Cc:Subject:Date:Reply-To; b=VfljycdtIWhDv/AVn3kWqVEhNkz4p2kKyXJTHjVs9aF/J4cBE3PFzbW1IwLJG6MO6 teydcs2TcoBeAuUpXX4a6P4BpqPb8oLdnDFPHgl6c4JYrr1S1kaa09TcRRj767uHXK HbkNF4bujns73iY8M3KiCS8MsswuQ8Xs2J6ZXjGA= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-72122: can: bcm: fix lockless bound/ifindex race and silent RX_SETUP failure Date: Sat, 15 Aug 2026 15:03:21 +0900 Message-ID: <2026081528-CVE-2026-72122-b990@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=4451; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=ZUXY1sjvSOSrAnBXC4qezNkbUQlHDZ+fW8BFlJFHplI=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkNDDv+MCS8f1m96mTell0SkgwvjrVZLzf6a3ZKLO77H /lF2+fbdcSyMAgyMciKKbJ82cZzdH/FIUUvQ9vTMHNYmUCGMHBxCsBEBKIY5udebfyfcantj04+ f+T8kwIKZ7VS2BjmCj1/wCjBe3XxW6sz9qvi5pUeKuObAgA= 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: can: bcm: fix lockless bound/ifindex race and silent RX_SETUP failure bcm_sendmsg() reads bo->ifindex and checks bo->bound before taking lock_sock(), while bcm_notify(), bcm_connect() and bcm_release() all mutate both fields under that same lock. Because the lockless reads and the locked writes are unordered with respect to each other, a racing bcm_notify() (device unregister) or bcm_connect() (concurrent bind on another thread sharing the socket) can make bcm_sendmsg() observe an inconsistent combination, e.g. a stale bound=1 together with the now-cleared ifindex=0, silently turning a socket bound to a specific CAN interface into one that also matches "any" interface. Keep the lockless bo->bound check purely as a fast-path reject, and move the ifindex read (and a bo->bound re-check) into the locked section, where every writer already serializes. This removes the possibility of observing the two fields torn against each other, rather than trying to fix it with more READ_ONCE()/WRITE_ONCE() pairs on two independently updated fields. Annotate the now-purely-lockless bo->bound accesses consistently across all its write sites. Also fix bcm_rx_setup() silently returning success when the target device disappears concurrently instead of reporting -ENODEV, so a broken RX op is no longer left registered as if it had succeeded. The Linux kernel CVE team has assigned CVE-2026-72122 to this issue. Affected and fixed versions =========================== Issue introduced in 2.6.25 with commit ffd980f976e7fd666c2e61bf8ab35107efd11828 and fixed in 5.10.261 with commit 9e60c586faeaed80d55ab8ce2a4b8e56133bc395 Issue introduced in 2.6.25 with commit ffd980f976e7fd666c2e61bf8ab35107efd11828 and fixed in 5.15.212 with commit ffa80a2af27c97453861a5128e537214a31cd18a Issue introduced in 2.6.25 with commit ffd980f976e7fd666c2e61bf8ab35107efd11828 and fixed in 6.1.178 with commit 6bcc5cd247c2934373bc2a1cdf8bf12321169543 Issue introduced in 2.6.25 with commit ffd980f976e7fd666c2e61bf8ab35107efd11828 and fixed in 6.6.145 with commit 0f6f9f95294b4cbb26ba02209e893e3bd91237c3 Issue introduced in 2.6.25 with commit ffd980f976e7fd666c2e61bf8ab35107efd11828 and fixed in 6.12.97 with commit b70f1a15533afeeec5d07f20bec3f3867ab1c7b6 Issue introduced in 2.6.25 with commit ffd980f976e7fd666c2e61bf8ab35107efd11828 and fixed in 6.18.40 with commit 35f0ac19efb1a3f6c5e12c00e475a9ec2d9c3a6d Issue introduced in 2.6.25 with commit ffd980f976e7fd666c2e61bf8ab35107efd11828 and fixed in 7.1.5 with commit b9c6ac6fb4e01b34575816066e5d3890a57b3c86 Issue introduced in 2.6.25 with commit ffd980f976e7fd666c2e61bf8ab35107efd11828 and fixed in 7.2-rc4 with commit d9b091d9d22fee81ec53fb55d2032951993ceadb 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-2026-72122 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/can/bcm.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/9e60c586faeaed80d55ab8ce2a4b8e56133bc395 https://git.kernel.org/stable/c/ffa80a2af27c97453861a5128e537214a31cd18a https://git.kernel.org/stable/c/6bcc5cd247c2934373bc2a1cdf8bf12321169543 https://git.kernel.org/stable/c/0f6f9f95294b4cbb26ba02209e893e3bd91237c3 https://git.kernel.org/stable/c/b70f1a15533afeeec5d07f20bec3f3867ab1c7b6 https://git.kernel.org/stable/c/35f0ac19efb1a3f6c5e12c00e475a9ec2d9c3a6d https://git.kernel.org/stable/c/b9c6ac6fb4e01b34575816066e5d3890a57b3c86 https://git.kernel.org/stable/c/d9b091d9d22fee81ec53fb55d2032951993ceadb