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 59734580395 for ; Wed, 9 Sep 2026 16:19:59 +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=1788970801; cv=none; b=NQJOdJ4qOcuuYymmhtLt3kyay2y5YMoNthpnt6fH1DdQqvcerGrLjdD00wsJEXBs/WV20UGODn7kf1Ufhl2p1C8QslmfE26rlhj0qTGBzfZcBJTNXeNdRZiMqYj7vVydfbSfaMwt9i0uOy3gGGHNxO3TA9kNsdmwKQUeCqF3R5g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788970801; c=relaxed/simple; bh=04cyG59hZu+HaJb/Oiouv0lHFSG2RefSAWg+4qOQ7FU=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=qnHkCyCaxt4Ggyi71oXXxHmIFdsTrfZzKvmSKm8K3dP1DmN+2WmUKv0KmmvtLmH6s1I48kqLvpmbniK6MjWmT6ZJ9Vby0vdzILsY5qmS7hDBbVibwnOuQjU0UhZ9XJ0fU7ecWF3zKlZlzJDcoPd6w6PeTeRURTraG0+qX0rH1Kk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=xwmkEmoT; 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="xwmkEmoT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4FEDB1F000FF; Wed, 9 Sep 2026 16:19:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788970799; bh=SV9Np4+YDhwNNWe2tBqrBxwVo66oslgQAPeennnIZDU=; h=From:To:Cc:Subject:Date:Reply-To; b=xwmkEmoTP4s5OyN3QyzfnH/vvxCEsX2F+7682zKDveufpYiRBqAAP6zrZGyyGkvgX QqMC/KedscKtWaI5EEMNZU66C3Ss5Ib87YTN9jIvaGHfRPfPvUlGCdlCytR6t0hzWA XMLZ6WWKI2N6GY3R/Oopx/QoJhNnXr+dy8+NxMaM= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-80923: xhci: dbgtty: Fix unregister on tty_register_driver() failure Date: Wed, 9 Sep 2026 18:19:45 +0200 Message-ID: <2026090943-CVE-2026-80923-3fb0@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=4004; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=4KQgGdPSq+6wXEEV180TqKzw0cV+t05+SMI+J0lsmxM=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkL2+XvsLDfFlmp9CfX4IfE79N99Z0urQwM3VOezQmPS lW90LWkI5aFQZCJQVZMkeXLNp6j+ysOKXoZ2p6GmcPKBDKEgYtTACYSUMmwYMe874VHtCf9+njR c2FbZeGf7N2tyxjml1T1hM2sm60slp/Xp5PHfdVufvFcAA== 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: xhci: dbgtty: Fix unregister on tty_register_driver() failure If tty_register_driver() fails, it drops the reference, but fails to set the global dbc_tty_driver to NULL, causing the unregister to be called again when module exits. On module unload dbc_tty_exit() only gates its cleanup on the driver pointer being non-NULL, so it operates on the already-freed driver: module_init(xhci_hcd_init) xhci_hcd_init() xhci_dbc_init() [return value ignored] dbc_tty_init() tty_register_driver() fails tty_driver_kref_put() -> driver freed (dbc_tty_driver left dangling) ... module_exit(xhci_hcd_fini) xhci_hcd_fini() xhci_dbc_exit() dbc_tty_exit() if (dbc_tty_driver) -> true (dangling) tty_unregister_driver() -> use-after-free The Linux kernel CVE team has assigned CVE-2026-80923 to this issue. Affected and fixed versions =========================== Issue introduced in 5.9 with commit 4521f16139409cdf9462c7325d43454462cff6c3 and fixed in 5.15.220 with commit 01b7bc0938061f2fd46e0094f6483d8c6c02f7d3 Issue introduced in 5.9 with commit 4521f16139409cdf9462c7325d43454462cff6c3 and fixed in 6.1.187 with commit 43635ff6401ca0e0ed21875379eeded921321525 Issue introduced in 5.9 with commit 4521f16139409cdf9462c7325d43454462cff6c3 and fixed in 6.6.156 with commit eaca2814f32b9872a332326324b9e83e01f156d2 Issue introduced in 5.9 with commit 4521f16139409cdf9462c7325d43454462cff6c3 and fixed in 6.12.108 with commit 943f976c93e70563b132f5585ff68b08c89641a2 Issue introduced in 5.9 with commit 4521f16139409cdf9462c7325d43454462cff6c3 and fixed in 6.18.49 with commit 0d0faf3cc44c4d86fc6faf5cea972c0fbe00b922 Issue introduced in 5.9 with commit 4521f16139409cdf9462c7325d43454462cff6c3 and fixed in 7.1.13 with commit 33ed35ca629477f57e0dd1d77d6df96cf5a9eb55 Issue introduced in 5.9 with commit 4521f16139409cdf9462c7325d43454462cff6c3 and fixed in 7.2.3 with commit 0e469b94fbba8eb03666da41dd1082b793c50c1a Issue introduced in 5.9 with commit 4521f16139409cdf9462c7325d43454462cff6c3 and fixed in 7.3-rc1 with commit a916fa66a43e10f63198b6ce978badffc678821a 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-2026-80923 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/usb/host/xhci-dbgtty.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/01b7bc0938061f2fd46e0094f6483d8c6c02f7d3 https://git.kernel.org/stable/c/43635ff6401ca0e0ed21875379eeded921321525 https://git.kernel.org/stable/c/eaca2814f32b9872a332326324b9e83e01f156d2 https://git.kernel.org/stable/c/943f976c93e70563b132f5585ff68b08c89641a2 https://git.kernel.org/stable/c/0d0faf3cc44c4d86fc6faf5cea972c0fbe00b922 https://git.kernel.org/stable/c/33ed35ca629477f57e0dd1d77d6df96cf5a9eb55 https://git.kernel.org/stable/c/0e469b94fbba8eb03666da41dd1082b793c50c1a https://git.kernel.org/stable/c/a916fa66a43e10f63198b6ce978badffc678821a