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 A24C44052A5 for ; Fri, 4 Sep 2026 15:56:31 +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=1788537395; cv=none; b=je3rOH5bS4ze03p8xf8nltzgRYQWF/dhM5pl1nVimZAWPFd3V7YLZur8P3zaxVNXM4JyDxS10BJLUCHW+sODhcBKfse9nb7bqNMky/dR83T3DiAAUbKvs1CiK81Gc2Dy8icSizu+uVru3zgvRRlC1p6rnAh/kXezwpFZ9z1+BrI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788537395; c=relaxed/simple; bh=7k4BfuBrb/abW8LdI5TCrnvY3SCv+7NfK4AXa4Y5p7o=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=qufdz19ZPtmb/aNrFY5e5G/62RXy2iOTlsj5/Cm8qf8lFzZhtCyksIIhOgSluc6r8yzLChIhaiEhKQjPcFTddMlwIL5kegKAPeJpf9jVvW9LsE9L6y9rpLHMbNrB32ipXc3BzyYXNDXTXqR+1VFsuP3WB2bAQcAwffSkFRygjn0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=C+56s5sZ; 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="C+56s5sZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B15E31F00A3E; Fri, 4 Sep 2026 15:56:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788537390; bh=V9LtObp1bwe/4j1iZvYXavV83ylyS7WQ1898IaXJ5kk=; h=From:To:Cc:Subject:Date:Reply-To; b=C+56s5sZ6nHp1cLUk9m1ySo3RY1W00k8stnOtn1K3DHGqcTseqbV1TG5IyodJInYT o0kIYQux3OWWcr3bqpSZTnP0v9ahU/NAqvHqiHNfU9csD5IRtwWCEY+dhjoNKTailJ 9PI7RY+f4hYcox0h6M1kFrKZzsVVAgkSr/0TyoZM= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-80829: ALSA: usb-audio: fix OOB write in snd_usbmidi_novation_output() Date: Fri, 4 Sep 2026 17:52:56 +0200 Message-ID: <2026090455-CVE-2026-80829-c6d6@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=4713; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=NvhvwF2Dnev6u3LIftcjpZqansD9o7c/n+Fw19w9Cvc=; b=owGbwMvMwCRo6H6F97bub03G02pJDFmzXobfqju33mHffE7et88XTowJSujyKVCO5gg6bB3Xw 6PG9ehBRywLgyATg6yYIsuXbTxH91ccUvQytD0NM4eVCWQIAxenAExEU5xhDmdqIL9f487Kewv2 f/V523FkyYfb8xjmaeQLTFMQfVqwyOf3W8VveVuerju7FwA= 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: ALSA: usb-audio: fix OOB write in snd_usbmidi_novation_output() snd_usbmidi_novation_output() lays out a two-byte header at transfer_buffer[0..1] and passes &transfer_buffer[2] together with a length of ep->max_transfer - 2 to snd_rawmidi_transmit(): count = snd_rawmidi_transmit(ep->ports[0].substream, &transfer_buffer[2], ep->max_transfer - 2); ep->max_transfer comes from the output endpoint's wMaxPacketSize via usb_maxpacket(). A malformed or malicious device can advertise a bulk OUT endpoint with a wMaxPacketSize of 1 - the USB core only clamps this value downwards - so ep->max_transfer becomes 1 and the count argument becomes -1. snd_rawmidi_transmit() passes the negative count on to __snd_rawmidi_transmit_peek(), where "if (count1 > count) count1 = count" leaves count1 negative; get_aligned_size() keeps it negative for a byte-stream substream, so the following memcpy(buffer, ..., count1) runs with a (size_t)-1 length and writes far past the transfer buffer, which was allocated with usb_alloc_coherent(ep->max_transfer). This is the same class of bug that was fixed for snd_usbmidi_akai_output() in commit 0970274613fb ("ALSA: usb-audio: fix OOB write in snd_usbmidi_akai_output()"); the novation output routine was left unguarded. Bail out when the endpoint cannot hold the two-byte header plus at least one payload byte. The Linux kernel CVE team has assigned CVE-2026-80829 to this issue. Affected and fixed versions =========================== Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 5.10.269 with commit 558fc4485ecc704edfe7876d6cebae4738ff7ef8 Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 5.15.220 with commit 9c8212436631b0063cb021e9f58df438e3db84d0 Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.1.187 with commit e9c00d7533f99aa9833c4b598f47e3b3202fdb9a Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.6.156 with commit 94e4562fcc81badd1d467ddfb88c27e4fae974c2 Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.12.108 with commit 7639ec9755d3ec0ec8cd7c0fdd2c3d3997434870 Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 6.18.49 with commit 91919b3b99ab7ce3d7dbb39fcf7c6c742a663c0c Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.1.13 with commit 7f00dbddb51f4f74325cdc7c3f6b19fb3392481a Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.2.3 with commit 1074c2306901b44ebcb83855583c6776e1e392ea Issue introduced in 2.6.12 with commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and fixed in 7.3-rc1 with commit 1035a8f63bae28e498b0e7b5ac91d749844a7158 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-2026-80829 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: sound/usb/midi.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/558fc4485ecc704edfe7876d6cebae4738ff7ef8 https://git.kernel.org/stable/c/9c8212436631b0063cb021e9f58df438e3db84d0 https://git.kernel.org/stable/c/e9c00d7533f99aa9833c4b598f47e3b3202fdb9a https://git.kernel.org/stable/c/94e4562fcc81badd1d467ddfb88c27e4fae974c2 https://git.kernel.org/stable/c/7639ec9755d3ec0ec8cd7c0fdd2c3d3997434870 https://git.kernel.org/stable/c/91919b3b99ab7ce3d7dbb39fcf7c6c742a663c0c https://git.kernel.org/stable/c/7f00dbddb51f4f74325cdc7c3f6b19fb3392481a https://git.kernel.org/stable/c/1074c2306901b44ebcb83855583c6776e1e392ea https://git.kernel.org/stable/c/1035a8f63bae28e498b0e7b5ac91d749844a7158