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 3E66E385D7B for ; Wed, 9 Sep 2026 10:19:05 +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=1788949147; cv=none; b=MiUY5RfLZifjglkghbuJIWlpR7LLVlLaDNZaKx8U0MJPq5ohQWtPd6h6tUEzfDxuYvb7nS3g5hE9Y82ui0JyESpya3tuIplFtOwjuXXaVJt91O29m7gp8OTdRSYu0G2gj1atzPZkPdCX0xMI06ayBIVAUtS7KQyg1oc5fdCiIvs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788949147; c=relaxed/simple; bh=ms9OR/xlVMR07Jxo6mS34a1cLOBS0QDUgTLcIl8b1fA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=n6iJCGfjDxzpaOGGmmB1OU083TG0dSUIsiWn3hDJuS5wkvaMT9W11xl3GzNF++lRchrlVEWGF7+YMZsjIdQXZkrhHnzDM1ZKRlP/OrtWir/SVUQ2D76QHSweIMnE2S4RyETEJkfcV6wnf9c63Azc7aVBopzAC8bdZ33HcrNFF5M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=OmuP3ZDR; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="OmuP3ZDR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ACC291F00A3A; Wed, 9 Sep 2026 10:19:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788949145; bh=x6Xab70ESD9t/6pmYeLscjnLA0tFxN5sjfKwNytDYIc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=OmuP3ZDRmjh9QeIt2hTq1tPG7pye+BBIeOQMi93xR5B1ZjQv+YAXFascxVZ3zwW70 hsOIXd+NZitSIXRMvpy2zQ5F1dQzioKAcVEUqfjOpV3+4n6n2Pjp01wqU/L0+MUopt fSaEep1/nVOKYT5oCwqEVf7lAsJA5TecnwJn66lF4DjnB/D74cbY9WOIPNTBbX/PRf 8V60TojPzeYvChY7i5ql+d7WGD9a8d3z7KDzSqVdMxFxA44ooBw6nl+aDvukKZ53/V PvPly6OW1VslsfDEnWJ1u0XpISiSvfA2hRTS3chKsIzfE48DSshBFx4p2NM+UjJw3j eJCLIjLVwd1NA== From: Sasha Levin To: stable@vger.kernel.org Cc: Joseph Qi , Heming Zhao , Mark Fasheh , Joel Becker , Junxiao Bi , Changwei Ge , Jun Piao , Andrew Morton , Sasha Levin Subject: [PATCH 6.12.y 1/2] ocfs2: validate dx_root extent list fields during block read Date: Wed, 9 Sep 2026 06:19:02 -0400 Message-ID: <20260909101903.1491952-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026090340-backside-dangling-fd8e@gregkh> References: <2026090340-backside-dangling-fd8e@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Joseph Qi [ Upstream commit 775c17386a6fd695f999d4cda90e3931386570dd ] Patch series "ocfs2: consolidate extent list validation into block read callbacks". ocfs2 validates extent list fields (l_count, l_next_free_rec) at various points during extent tree traversal. This is fragile because each caller must remember to check for corrupted on-disk data before using it. This series moves those checks into the block read validation callbacks (ocfs2_validate_dx_root and ocfs2_validate_extent_block), so corrupted fields are caught early at block read time. Redundant post-read checks are then removed. This patch (of 4): Move the extent list l_count validation from ocfs2_dx_dir_lookup_rec() into ocfs2_validate_dx_root(), so that corrupted on-disk fields are caught early at block read time rather than during directory lookups. Additionally, add a l_next_free_rec <= l_count check to prevent out-of-bounds access when iterating over extent records. Both checks are skipped for inline dx roots (OCFS2_DX_FLAG_INLINE), which use dr_entries instead of dr_list. Link: https://lkml.kernel.org/r/20260403090803.3860971-1-joseph.qi@linux.alibaba.com Link: https://lkml.kernel.org/r/20260403090803.3860971-2-joseph.qi@linux.alibaba.com Signed-off-by: Joseph Qi Reviewed-by: Heming Zhao Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Cc: Changwei Ge Cc: Jun Piao Signed-off-by: Andrew Morton Stable-dep-of: bc70726ddad5 ("ocfs2: validate directory-index entry counts when reading metadata") Signed-off-by: Sasha Levin --- fs/ocfs2/dir.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c index 119771c4a2ed3..6b9f6890c6090 100644 --- a/fs/ocfs2/dir.c +++ b/fs/ocfs2/dir.c @@ -580,7 +580,7 @@ static int ocfs2_validate_dx_root(struct super_block *sb, mlog(ML_ERROR, "Checksum failed for dir index root block %llu\n", (unsigned long long)bh->b_blocknr); - return ret; + goto bail; } if (!OCFS2_IS_VALID_DX_ROOT(dx_root)) { @@ -588,8 +588,32 @@ static int ocfs2_validate_dx_root(struct super_block *sb, "Dir Index Root # %llu has bad signature %.*s\n", (unsigned long long)le64_to_cpu(dx_root->dr_blkno), 7, dx_root->dr_signature); + goto bail; + } + + if (!(dx_root->dr_flags & OCFS2_DX_FLAG_INLINE)) { + struct ocfs2_extent_list *el = &dx_root->dr_list; + + if (le16_to_cpu(el->l_count) != ocfs2_extent_recs_per_dx_root(sb)) { + ret = ocfs2_error(sb, + "Dir Index Root # %llu has invalid l_count %u (expected %u)\n", + (unsigned long long)le64_to_cpu(dx_root->dr_blkno), + le16_to_cpu(el->l_count), + ocfs2_extent_recs_per_dx_root(sb)); + goto bail; + } + + if (le16_to_cpu(el->l_next_free_rec) > le16_to_cpu(el->l_count)) { + ret = ocfs2_error(sb, + "Dir Index Root # %llu has invalid l_next_free_rec %u (l_count %u)\n", + (unsigned long long)le64_to_cpu(dx_root->dr_blkno), + le16_to_cpu(el->l_next_free_rec), + le16_to_cpu(el->l_count)); + goto bail; + } } +bail: return ret; } -- 2.53.0