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 A234E51615B for ; Thu, 17 Sep 2026 16:21:43 +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=1789662104; cv=none; b=uX6VMWRcobQHk9mnvefpys8RIM3yk8zoeotf2o+Eg+9cvqyFwy5sqAX7jkQwumAU9oI2RGd/UIxV4IVDUv+KQQ6/Fccw6gEFdYYq7V7x4WjzGpzImM0BlDivzVDORym578pxwbFKaHdu01gKen35+i6nkYlFeGEr9/8R0DeNj7g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789662104; c=relaxed/simple; bh=T60i8lKhm4C1O54aCosQO5NJzddcVEpw8H9A7flfEXw=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=EcORZ0RjuMeSpPlpEl8qIUTFK0zvbpXlUmN0mDzVQCgoo0aJRWUbameLsRXQc1blacbpyNVp0yC8i7XR908Ygw/lLbDd7nkTQoXrKlmWs8E8CELP6TuNvIvErAgLvVJcpP6bNd6RYJx4L7IMpsmeSzkizlD+5r3b6l2GsY87VTM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=HzBxtiV7; 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="HzBxtiV7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 052BA1F000FF; Thu, 17 Sep 2026 16:21:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789662103; bh=pThNY3XFnsV2kz4sO8mAwXUQvyJfbPIUR/Mx9Kv4JBU=; h=From:To:Cc:Subject:Date:Reply-To; b=HzBxtiV71Kd2m/3a6kw6fsmP11SLWvnFYj6OwkBuMCP+OdDDC4tXqpTD1z66X3jBw uVhe3BJQ1xCwX0OsqrIPFol3TS1NuyG/YFrRjuV08z3T0AhKQv1EnLNlsSvfAzV9Yv stK5WAAyrelFE9NT6KUIGdfTGsOvkxCB4r8hLHFQ= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-90206: nvmet: fix max_qid race between configfs and controller allocation Date: Thu, 17 Sep 2026 17:10:36 +0100 Message-ID: <2026091735-CVE-2026-90206-e629@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=3334; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=1Qk3jomoYdu4mUuPsLbKd4y5hMgu34yFDuLG6gfzAag=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlrBJpr3nyo2S4sfWmmhyzrlNfC52dvM97/+Xj8Pp/yi +pLSxkmd8SyMAgyMciKKbJ82cZzdH/FIUUvQ9vTMHNYmUCGMHBxCsBEbr9nWLDg7e+TevVXsywv HT3isuCewL3+Cx4MCw4/+CJ0yabsaNFj5yNGnlsuBahYfQMA 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: nvmet: fix max_qid race between configfs and controller allocation The function nvmet_subsys_attr_qid_max_store() can race against nvmet_alloc_ctrl() when a subsystem's max_qid limit is modified. Suppose max_qid is currently 64. If nvmet_alloc_ctrl() executes: ctrl->sqs = kzalloc_objs(struct nvmet_sq *, subsys->max_qid + 1); and at this exact point, a userspace process changes max_qid to 128, nvmet_subsys_attr_qid_max_store() will set the new max_qid value. It attempts to delete active controllers to force a reconnect, but the new controller won't be deleted because it hasn't been added to the subsys->ctrls list yet. nvmet_alloc_ctrl() then proceeds and adds the new controller to the subsys->ctrls list. Later, when nvmet_install_queue() is called, it will see max_qid set to 128, but the memory allocated for sqs is only sized for 64 entries. This results in a KASAN out-of-bounds warning and potential memory corruptions. Fix this by protecting the queue allocations and list insertion in nvmet_alloc_ctrl() with down_read(&nvmet_config_sem). Because nvmet_subsys_attr_qid_max_store() acquires down_write(&nvmet_config_sem) to modify the attribute, this safely prevents the configfs writer from modifying max_qid during controller creation. Copy the max_qid from the subsystem to the controller's structure during the allocation; ctrl->max_qid never changes as long as the controller remains in LIVE state, so this will prevent similar race conditions. The Linux kernel CVE team has assigned CVE-2026-90206 to this issue. Affected and fixed versions =========================== Issue introduced in 6.1 with commit 3e980f5995e0bb4d86fef873a9c9ad66721580d0 and fixed in 7.2.6 with commit 2c23fc91789dfd9db746edb3ae9b90d65fabd410 Issue introduced in 6.1 with commit 3e980f5995e0bb4d86fef873a9c9ad66721580d0 and fixed in 7.3-rc1 with commit f1a8846e06388113dfdbb89dee005083fa9afdf9 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-2026-90206 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/nvme/target/admin-cmd.c drivers/nvme/target/core.c drivers/nvme/target/fabrics-cmd.c drivers/nvme/target/nvmet.h drivers/nvme/target/pci-epf.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/2c23fc91789dfd9db746edb3ae9b90d65fabd410 https://git.kernel.org/stable/c/f1a8846e06388113dfdbb89dee005083fa9afdf9