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 DDE243624AB for ; Sat, 15 Aug 2026 06:16:20 +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=1786774582; cv=none; b=IXGaXI+UU9/Uy7rEDN1D396snPVzzrsp9lBiF2Csj4niznBOUp17y/pVEiGngNT7itEJRyAPQ5f1HcnjTjm2z48kAKX7uEyHeDPL8Z9OvBqz4P8/MZ2Ys54F7WZL+NDtaqNW9ooBDgBxLxKlOI3tAK7CznkHQeGEuTJ2kiUlkwY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786774582; c=relaxed/simple; bh=4ybMxtRZcz9qAOeCdXVu0172eiHKk8P7x6yVpMgBA+Y=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=drf1c8IEGOG4XgnYqxPtHRRVa2RBjTqis8lCDj4Fbk2Q/7nsPyVv6diiSsxWUTh9DUukLd4SVi2klaC0xB4lE2cZIE3VXGB2jKHrmJYI0T0Fkvc+VBvypd2heh98iZJfrCkogPk2P7QrXjKYW4Al401rOG9a6cE7i2rBlQyomNM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=F2fe3ydI; 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="F2fe3ydI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3818B1F000E9; Sat, 15 Aug 2026 06:16:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786774580; bh=1dMMQUkwLpIG22m81KMMJQWr/FHCGyeYzGUemX4L8wE=; h=From:To:Cc:Subject:Date:Reply-To; b=F2fe3ydIC528svUKmicTUJJinb7huJbQynzXPo6qQDhxf5dSIKN73t+xJTwPAc+oB hfcDghtpAdcHd838QM8ZtkhClMU1nfhGO2VgxsApRmpIWHJlXEnSThQwWPwXO0godI sY6u2DHKEWBs6aln/4hBFencoaOpMlKz9og+OEqU= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-72202: ntfs: avoid heap allocation for free-cluster readahead state Date: Sat, 15 Aug 2026 15:04:41 +0900 Message-ID: <2026081543-CVE-2026-72202-5135@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=2445; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=BtPRii+4wVZkPv/HHIhRuC6UOBCZImCReurLiV+5jrE=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkNDCcmp8s79U5u3L6Od0+nXPrn3+ZW+jE5L1MS5+hc6 Q9x/i7VEcvCIMjEICumyPJlG8/R/RWHFL0MbU/DzGFlAhnCwMUpABPROs0wT+GvV1+b8vXu4Pnq 2o+k9nPtTmvVY5hnNJXl7f5Hs1Mdjncr7TmXpctkH/kfAA== 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: ntfs: avoid heap allocation for free-cluster readahead state get_nr_free_clusters() allocates a temporary file_ra_state before it publishes the precomputed free cluster count, sets NVolFreeClusterKnown(), and wakes vol->free_waitq. If that allocation fails, the worker returns without setting the flag or waking waiters, so callers waiting for the free count can block indefinitely. The readahead state is only used synchronously while scanning the bitmap. Keep it on the stack and pass it by address to the readahead helper. This eliminates the early allocation failure path instead of adding a special case that publishes a conservative count and wakes the waitqueue. Zero-initialize the on-stack state because file_ra_state_init() only sets ra_pages and prev_pos. Apply the same treatment to __get_nr_free_mft_records(), which scans the MFT bitmap with the same short-lived readahead state. The Linux kernel CVE team has assigned CVE-2026-72202 to this issue. Affected and fixed versions =========================== Fixed in 7.1.5 with commit 40ee64e633e5e413f2255bb48c063977d8c86f34 Fixed in 7.2-rc1 with commit c05132077df57a384919f61d7f8a8e76d748a6d4 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-2026-72202 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: fs/ntfs/super.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/40ee64e633e5e413f2255bb48c063977d8c86f34 https://git.kernel.org/stable/c/c05132077df57a384919f61d7f8a8e76d748a6d4