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 E0301576ED2; Wed, 9 Sep 2026 14:38:13 +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=1788964695; cv=none; b=PRThPTm7YUThFhjA9rbQKwnVZjRbmqAUl+N9ZvNp2f2vf6d2PajlzOUHW/TlrgCtiaQcraDufOgkCzS8mTY8Z1jSWmr4BxdgYhrmVCU4Irztvcyz7OGX3SY8pVDQxtpPiZZbPaGB5zcsDxOoQtawjJe+AYjYVhTvJxCnkFdzafc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788964695; c=relaxed/simple; bh=los1Y+arljoMV32ak3GGuGtl8atsf7lNL6MJLCCwsvc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=UPoVeAUTBONjSF0Nv/lR84/z7GZxiX8vaCq55qnFI6qY8iHN7lIf7+YqaC+J/fcRGT5uWHd+ZC5n8IkoM2U3HcaRusBUGN2sZzgFRGFw1l8YZRf+uPkIRPRK7YOmNmZ6JikByYBlTOMSYu36aGGzYfOQbcCPgP2m0WcAiWS2Gzk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=L5lRxsy4; 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="L5lRxsy4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4B5E11F00A3A; Wed, 9 Sep 2026 14:38:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788964693; bh=8dewr8rlGJeAHk5yAZEaTVlXECQqdYxjGO/CCN+Af9U=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=L5lRxsy4s8Yhq/CnhCP2qzijPoraCodfbMqI3hsXa9T1YbmyKigcn17w64HC0ress /VAwlmBtCJm2w5kp/opVosZkqYm4UZy4R9K6JCRllmieEq8B4QbocQ+d18U5ahCYOR AB7AKqe5udzJLm9awZR8rfb5+VMWVBoi5cKgFE9U= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Doruk Tan Ozturk , Joseph Qi , Joel Becker , Kees Cook , Mark Fasheh , Junxiao Bi , Changwei Ge , Jun Piao , Heming Zhao , Andrew Morton , Sasha Levin Subject: [PATCH 6.18 510/583] ocfs2: validate directory-index entry counts when reading metadata Date: Wed, 9 Sep 2026 15:43:15 +0200 Message-ID: <20260909134255.419093301@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260909134237.773280130@linuxfoundation.org> References: <20260909134237.773280130@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Doruk Tan Ozturk [ Upstream commit bc70726ddad53c7e9a9a85915bf2415b0d4f42f9 ] ocfs2_validate_dx_leaf() and ocfs2_validate_dx_root() check the ECC and signature of an indexed-directory block before it reaches higher-level callers, but neither validator bounds the ocfs2_dx_entry_list counts against the capacity of the block that holds them. ocfs2_dx_dir_search() then walks for (i = 0; i < le16_to_cpu(entry_list->de_num_used); i++) dx_entry = &entry_list->de_entries[i]; over de_num_used entries with no bounds check. entry_list is either dx_leaf->dl_list (from ocfs2_read_dx_leaf) or, for an inline root, dx_root->dr_entries. A crafted on-disk image can set de_num_used (and de_count, which is the __counted_by_le() bound of de_entries) to 0xffff and make the walk read far past the end of the 4KB metadata block, giving a slab out-of-bounds read reachable from any path lookup, stat() or open() on an indexed directory once the image is mounted. Commit 775c17386a6f ("ocfs2: validate dx_root extent list fields during block read") already bounds dr_list for the non-inline dx_root, but left the inline dr_entries path and the dx_leaf dl_list unchecked. Add the same read-time validation for both entry lists: de_count must equal the capacity of the block (ocfs2_dx_entries_per_leaf()/per_root()) and de_num_used must not exceed de_count, rejecting corrupted metadata with -EFSCORRUPTED before ocfs2_dx_dir_search() can walk an out-of-range entry array. de_count is always written as exactly the block capacity when a leaf or inline root is formatted, so the equality check does not reject any valid image. Found by 0sec automated security-research tooling (https://0sec.ai). Link: https://lore.kernel.org/20260713205625.92391-1-doruk@0sec.ai Fixes: 9b7895efac90 ("ocfs2: Add a name indexed b-tree to directory inodes") Fixes: 4ed8a6bb083b ("ocfs2: Store dir index records inline") Assisted-by: 0sec:claude-opus-4-8 Signed-off-by: Doruk Tan Ozturk Reviewed-by: Joseph Qi Cc: Joel Becker Cc: Kees Cook Cc: Mark Fasheh Cc: Junxiao Bi Cc: Changwei Ge Cc: Jun Piao Cc: Heming Zhao Cc: Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- fs/ocfs2/dir.c | 45 +++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 41 insertions(+), 4 deletions(-) --- a/fs/ocfs2/dir.c +++ b/fs/ocfs2/dir.c @@ -611,6 +611,28 @@ static int ocfs2_validate_dx_root(struct le16_to_cpu(el->l_count)); goto bail; } + } else { + struct ocfs2_dx_entry_list *dl_list = &dx_root->dr_entries; + + if (le16_to_cpu(dl_list->de_count) != + ocfs2_dx_entries_per_root(sb)) { + ret = ocfs2_error(sb, + "Dir Index Root # %llu has invalid de_count %u (expected %u)\n", + (unsigned long long)le64_to_cpu(dx_root->dr_blkno), + le16_to_cpu(dl_list->de_count), + ocfs2_dx_entries_per_root(sb)); + goto bail; + } + + if (le16_to_cpu(dl_list->de_num_used) > + le16_to_cpu(dl_list->de_count)) { + ret = ocfs2_error(sb, + "Dir Index Root # %llu has invalid de_num_used %u (de_count %u)\n", + (unsigned long long)le64_to_cpu(dx_root->dr_blkno), + le16_to_cpu(dl_list->de_num_used), + le16_to_cpu(dl_list->de_count)); + goto bail; + } } bail: @@ -650,10 +672,25 @@ static int ocfs2_validate_dx_leaf(struct return ret; } - if (!OCFS2_IS_VALID_DX_LEAF(dx_leaf)) { - ret = ocfs2_error(sb, "Dir Index Leaf has bad signature %.*s\n", - 7, dx_leaf->dl_signature); - } + if (!OCFS2_IS_VALID_DX_LEAF(dx_leaf)) + return ocfs2_error(sb, "Dir Index Leaf has bad signature %.*s\n", + 7, dx_leaf->dl_signature); + + if (le16_to_cpu(dx_leaf->dl_list.de_count) != + ocfs2_dx_entries_per_leaf(sb)) + return ocfs2_error(sb, + "Dir Index Leaf # %llu has invalid de_count %u (expected %u)\n", + (unsigned long long)le64_to_cpu(dx_leaf->dl_blkno), + le16_to_cpu(dx_leaf->dl_list.de_count), + ocfs2_dx_entries_per_leaf(sb)); + + if (le16_to_cpu(dx_leaf->dl_list.de_num_used) > + le16_to_cpu(dx_leaf->dl_list.de_count)) + return ocfs2_error(sb, + "Dir Index Leaf # %llu has invalid de_num_used %u (de_count %u)\n", + (unsigned long long)le64_to_cpu(dx_leaf->dl_blkno), + le16_to_cpu(dx_leaf->dl_list.de_num_used), + le16_to_cpu(dx_leaf->dl_list.de_count)); return ret; }