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 0472F3A7590 for ; Sun, 19 Jul 2026 15:42:40 +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=1784475761; cv=none; b=BJBzgXdwJV6NhMBgB/78Jv7aIqj+SnJ83RqsuWIwBZtg4I27u4wPZlmn5g3SmoDXaIuXJmqqFsAOi/lWPkrZuf25/nx8E2Dij64CqsXH2Iu5Aas6lxTeQlJJMbeKMYbID3pOfRqRTjDbgzr0zYvqzkoMFDIkZIOWf+N64FWEH9U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784475761; c=relaxed/simple; bh=+N2CVQ/iO/XBbLUX0mTtmuOeoSVvpyRHJjlzXvOBqCw=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=gn6/K4qZH1cDg6soZTNV0fOZGAL/VGWar3S/nhtOuDqryD6cO2GuC8v9q+atWYe7eC2hc/1DEeX1uT7dQ840O1ZY19E2uUghpW6NKMtxaAEnMZr5w5jL/N7wA+K6P/WXqBk5uges70skTuvu1B3b/gS82xrOy/aeu4wMbQhe8RM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=wx5HrZug; 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="wx5HrZug" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6361A1F000E9; Sun, 19 Jul 2026 15:42:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784475759; bh=V+aDlbGmTpepTkLr3fwIdG7Nu8LUNZ4irLpYZ4tNrok=; h=From:To:Cc:Subject:Date:Reply-To; b=wx5HrZugYHlpWJRoe6h/RJLPuRmqAHeC7XEhGPqsSTSPRPlSHoqJK9HZ7ovLpiaxF 0QsmuyCPJ0MN4zADaCIllvjg2/egjrTX7UwbN55wzKc7TjkjyHQAlLkjHRMYAm0NeF fz4hV6gZoPaMwUE+qIJHOgpNreVXsNdVcSclO9fk= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-64074: fs/statmount: fix slab out-of-bounds write in statmount_mnt_idmap Date: Sun, 19 Jul 2026 17:38:56 +0200 Message-ID: <2026071913-CVE-2026-64074-06ce@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=2588; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=BB6liglV5spymksLjeoaeRCrE/n2tPkU5r6FUyl4ihM=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkx79MMFf0mfWOOehcxtczI7rvyd3lOPj7F4Kd7Vu8K+ bqmmC+5I5aFQZCJQVZMkeXLNp6j+ysOKXoZ2p6GmcPKBDKEgYtTACbCZMIwm2Xes+gphy22HI8X X5y1c2XzbC/eeIZ5lnNrH/jtsC7d4yOb9caGp9/wCUMkAA== 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: fs/statmount: fix slab out-of-bounds write in statmount_mnt_idmap statmount_mnt_idmap() writes one mapping with seq_printf() and then manually advances seq->count to include the NUL separator. If seq_printf() overflows, seq_set_overflow() sets seq->count to seq->size. The manual seq->count++ changes this to seq->size + 1. seq_has_overflowed() then no longer detects the overflow. The corrupted count returns to statmount_string(), which later executes: seq->buf[seq->count++] = '\0'; This causes a 1-byte NULL out-of-bounds write on the dynamically allocated seq buffer. Fix this by checking for overflow immediately after seq_printf(). The Linux kernel CVE team has assigned CVE-2026-64074 to this issue. Affected and fixed versions =========================== Issue introduced in 6.15 with commit 37c4a9590e1efcae7749682239fc22a330d2d325 and fixed in 6.18.34 with commit e37ea2c6f17f273813ea4e8e94c102591d598ce1 Issue introduced in 6.15 with commit 37c4a9590e1efcae7749682239fc22a330d2d325 and fixed in 7.0.11 with commit 93614949dc86f068e3c32c32cf1ee2a2323177a7 Issue introduced in 6.15 with commit 37c4a9590e1efcae7749682239fc22a330d2d325 and fixed in 7.1 with commit a3bf0f28d4ba16e1f35f8c983bb04426b87e2a78 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-2026-64074 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/mnt_idmapping.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/e37ea2c6f17f273813ea4e8e94c102591d598ce1 https://git.kernel.org/stable/c/93614949dc86f068e3c32c32cf1ee2a2323177a7 https://git.kernel.org/stable/c/a3bf0f28d4ba16e1f35f8c983bb04426b87e2a78