From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 171B2315D4B for ; Wed, 15 Oct 2025 07:58:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760515139; cv=none; b=adFHNXjV9fRss0adGGu7zDxzhclXwn6v7pvrgR1xdqrK73MZbXD3rY0BLVCOc/Z5ohtlNJo6FvlU3UeQovd+ScCno+bADjSOW+D7MBbY4viKv6ipwp+MJ73LAjA/O/WcZot1X+fKYMkheK0OaI/NZzk0tAmilGEG1bkmF14NjZg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760515139; c=relaxed/simple; bh=rH5WK1n1IdbymxLSbKJakRzZaZFt2Qbe6vlpFvpB12M=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=eokTFUqno+ZENj9H4xo2FoVJpVzSf8xjGq3esqJwtjdK6cBrK1bseYPgrqSgxMa0W2CjX8ZQJFH0VRFWc4vW3r9bkqRmYdgvlorCwqCNWtD3OBk8cI93/5sVQbTu7eJ0DBC+UIAO1Snx1VOu85EhQ/AspVy+UJZPT9NMisp/cnY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=dcthY7g1; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="dcthY7g1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 53EDDC4CEF8; Wed, 15 Oct 2025 07:58:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1760515138; bh=rH5WK1n1IdbymxLSbKJakRzZaZFt2Qbe6vlpFvpB12M=; h=From:To:Cc:Subject:Date:Reply-to:From; b=dcthY7g1Ql1nfdkmTkgbZImYa3v/txBPWkL+lZp2J719XVeNfQ1F8h9WASonthZDF fBKUwgzyUjj6Tjl7Nzij+31+OmbxyspO7FTk91Z1KKEuoXu6+H7n0tRZhfFQcG53Ec bM0BnTZ3G7vT1fZn9IFoahj94GRpdQEWcTrWbPs4= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2025-39999: blk-mq: fix blk_mq_tags double free while nr_requests grown Date: Wed, 15 Oct 2025 09:58:36 +0200 Message-ID: <2025101529-CVE-2025-39999-08ff@gregkh> X-Mailer: git-send-email 2.51.0 Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Reply-to: , X-Developer-Signature: v=1; a=openpgp-sha256; l=2640; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=8zuQHg97IYWDwu2tP0zQjjrdKJhNlv3yb9UUerzCykc=; b=owGbwMvMwCRo6H6F97bub03G02pJDBnvQ1RXzv8VI+z5yPx0Ymbr1EXBbNLrvXadT6tdePnn1 y2OD+PbO2JZGASZGGTFFFm+bOM5ur/ikKKXoe1pmDmsTCBDGLg4BWAiZxMYFvT8ZtkwoarZ4YHn h+wPC+J6z9glRzAs2Jlubrde8eF8m2vTHiktep17ONTiHAA= 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: blk-mq: fix blk_mq_tags double free while nr_requests grown In the case user trigger tags grow by queue sysfs attribute nr_requests, hctx->sched_tags will be freed directly and replaced with a new allocated tags, see blk_mq_tag_update_depth(). The problem is that hctx->sched_tags is from elevator->et->tags, while et->tags is still the freed tags, hence later elevator exit will try to free the tags again, causing kernel panic. Fix this problem by replacing et->tags with new allocated tags as well. Noted there are still some long term problems that will require some refactor to be fixed thoroughly[1]. [1] https://lore.kernel.org/all/20250815080216.410665-1-yukuai1@huaweicloud.com/ The Linux kernel CVE team has assigned CVE-2025-39999 to this issue. Affected and fixed versions =========================== Issue introduced in 6.16.4 with commit 58567d8e95c096ad234963df90a2ca518901f4b6 and fixed in 6.16.11 with commit 8faee580d63bc2a54a59dcdb7f9ce4de29384fec Issue introduced in 6.17 with commit f5a6604f7a4405450e4a1f54e5430f47290c500f and fixed in 6.17.1 with commit 392b1d64911f4de8887fe8b68299fa8bd6e5b923 Issue introduced in 6.17 with commit f5a6604f7a4405450e4a1f54e5430f47290c500f and fixed in 6.18-rc1 with commit ba28afbd9eff2a6370f23ef4e6a036ab0cfda409 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-2025-39999 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: block/blk-mq-tag.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/8faee580d63bc2a54a59dcdb7f9ce4de29384fec https://git.kernel.org/stable/c/392b1d64911f4de8887fe8b68299fa8bd6e5b923 https://git.kernel.org/stable/c/ba28afbd9eff2a6370f23ef4e6a036ab0cfda409