From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-118.freemail.mail.aliyun.com (out30-118.freemail.mail.aliyun.com [115.124.30.118]) (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 7CACD3AC0D9 for ; Mon, 31 Aug 2026 06:34:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.118 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788158050; cv=none; b=HT9g4Nq4piUovu8LZZnhPLz2f9TZCSyRS4gY6j2BF2QrKy9uvSx5q7al5LHAFzZcA7Y0jZ9+ii2/iQuEHMHOXZKy0ndxERM/4cAaA6PP3Z6cBvqrj8p5Jm5mTjhxGXCdv9LOW7U95jYT/iUW4zNBCJbVuG0bNieFGwY2qSFhrxo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788158050; c=relaxed/simple; bh=eGEpIjWJqdf8UYbb2QkQk0bxAPkQ7us4f4toxIOYLMQ=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=MbXi/4Vnlsx04L9g2cWOiiKSJvRdWKZZ+aMdupNkTNcCeX3Djcf2C1hEqWm2d0vCx6raa74Uorl/YQIeDaticc3y4PGyqE+7mFKHN+BNifMcGsZkj4j2sXpDnpVkSOZDsvlf7oQGGfCgeQn+AIPUikiDmkSIjQMs9+BZLdkk/1E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=FpTlJB3h; arc=none smtp.client-ip=115.124.30.118 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="FpTlJB3h" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1788158044; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=EIZTiLjzMsj8zvXrmlEKp70ozCBmN/0RJICpv67UVnE=; b=FpTlJB3hUBqD6bYwIwwDWXuQ0hx48NXuSeHfx60GrEq5qLp7K/oGGCXeyHqe/EeqGfRWUywuSrv69DfFNnQB6zH8axsVzeLySa4+MCr9MNT7kuj+U7cevtv6hVKJpxuLZsa8XW2syeMwSxaL3taxZQ9lVp4xF7glktN6pV0QOLM= X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R171e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033032089153;MF=joseph.qi@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0X9tzGpc_1788157731; Received: from localhost(mailfrom:joseph.qi@linux.alibaba.com fp:SMTPD_---0X9tzGpc_1788157731 cluster:ay36) by smtp.aliyun-inc.com; Mon, 31 Aug 2026 14:28:52 +0800 From: Joseph Qi To: Andrew Morton , Heming Zhao Cc: Mark Fasheh , Joel Becker , ocfs2-devel@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH 3/4] ocfs2: validate suballoc slot of xattr and dir index blocks Date: Mon, 31 Aug 2026 14:28:47 +0800 Message-Id: <20260831062848.2743436-4-joseph.qi@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20260831062848.2743436-1-joseph.qi@linux.alibaba.com> References: <20260831062848.2743436-1-joseph.qi@linux.alibaba.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit ocfs2_validate_xattr_block() and ocfs2_validate_dx_root() do not validate xb_suballoc_slot and dr_suballoc_slot against the mounted filesystem's slot range. Since xattr blocks and dir index root blocks are allocated from a per-slot suballocator at runtime, their suballoc slots must be within range. Otherwise a corrupted image can carry an out-of-range slot. When the xattr block or dir index is removed, ocfs2_xattr_block_remove() or ocfs2_dx_dir_remove_index() passes the unvalidated slot to ocfs2_get_system_file_inode() and get_local_system_inode() will either hit BUG_ON(slot == OCFS2_INVALID_SLOT) or compute an out-of-bounds index into the local_system_inodes array. Reject out-of-range suballoc slots during validation. Signed-off-by: Joseph Qi --- fs/ocfs2/dir.c | 14 ++++++++++++++ fs/ocfs2/xattr.c | 13 +++++++++++++ 2 files changed, 27 insertions(+) diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c index 0075e1624310..eb9850610ba3 100644 --- a/fs/ocfs2/dir.c +++ b/fs/ocfs2/dir.c @@ -605,6 +605,20 @@ static int ocfs2_validate_dx_root(struct super_block *sb, goto bail; } + /* + * Dir index root blocks are allocated from a per-slot suballocator, + * so the slot must be in range. Otherwise removing the index passes + * it to get_local_system_inode(), which hits BUG_ON() for + * OCFS2_INVALID_SLOT or computes an out-of-bounds index otherwise. + */ + if ((u32)le16_to_cpu(dx_root->dr_suballoc_slot) >= OCFS2_SB(sb)->max_slots) { + ret = ocfs2_error(sb, + "Dir Index Root # %llu has invalid dr_suballoc_slot %u\n", + (unsigned long long)le64_to_cpu(dx_root->dr_blkno), + le16_to_cpu(dx_root->dr_suballoc_slot)); + goto bail; + } + if (!(dx_root->dr_flags & OCFS2_DX_FLAG_INLINE)) { struct ocfs2_extent_list *el = &dx_root->dr_list; diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c index 0062cbeb1e8b..5acc8091d06f 100644 --- a/fs/ocfs2/xattr.c +++ b/fs/ocfs2/xattr.c @@ -517,6 +517,19 @@ static int ocfs2_validate_xattr_block(struct super_block *sb, le32_to_cpu(xb->xb_fs_generation)); } + /* + * Xattr blocks are allocated from a per-slot suballocator, so the + * slot must be in range. Otherwise freeing the block passes it to + * get_local_system_inode(), which hits BUG_ON() for + * OCFS2_INVALID_SLOT or computes an out-of-bounds index otherwise. + */ + if ((u32)le16_to_cpu(xb->xb_suballoc_slot) >= OCFS2_SB(sb)->max_slots) { + return ocfs2_error(sb, + "Extended attribute block #%llu has an invalid xb_suballoc_slot of %u\n", + (unsigned long long)bh->b_blocknr, + le16_to_cpu(xb->xb_suballoc_slot)); + } + if (!(le16_to_cpu(xb->xb_flags) & OCFS2_XATTR_INDEXED)) { size_t region_offset = offsetof(struct ocfs2_xattr_block, xb_attrs.xb_header); -- 2.39.3