From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-133.freemail.mail.aliyun.com (out30-133.freemail.mail.aliyun.com [115.124.30.133]) (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 ABFF724816D; Wed, 15 Jan 2025 09:50:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736934661; cv=none; b=LVixlPYaIXcIbE4j6Ej/wwMthUi+7bTM7mkcT4fvz5hNWjqUQEGUkaolVS/rmU+cLCD+1Q5nXGvILGtxw+l3FlyohzlBJbRNnFQwY98WyxHLyc/EhKzGL5//ry2KaseEpaspSXoqiGLSexd/yqf4oGVqFb7wpGrt0Polyn+lIPc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736934661; c=relaxed/simple; bh=nwfePTRPoRRFuCBUWXql9E3sSf2NsBtmCiTBH1uwAFM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AyyrPNMgt8Hn8HvLdtkRgjPR8raIWqduRfsHOfoB8/vVIxSVKaOWN9vHDvHYlMLHv5oZ7ez8PN2uzIh32iHUMHqQ5eKLAV4iDypZJBWcaPnA/0X8uyNwCR/ENd1wo/v/GQNy+mKWP0yICmBKlnI2Gda3cgIAKmRfojZ01z0UsHg= 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=vVDmYlN2; arc=none smtp.client-ip=115.124.30.133 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="vVDmYlN2" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1736934657; h=From:To:Subject:Date:Message-ID:MIME-Version; bh=3Rjkjm8Jq5H24ooOjCp1xVDbTvFXijBEgngWFzUKsAM=; b=vVDmYlN2tahMlHPeP60CtIwrDs8H9NpZ2v/95+7YXWZ+PAq8z0JL2qqMo1O4nRv5TSQZNQyRfA2BsvJrBZigNGg2EhxgSFL6bAWLtrkVTMlgtC9ksYcHebJQnCNYkeo07dbIEgSjRuthuRmPt1Ug9EQWiBlOXoPAANt8nQKIkqI= Received: from x31i01179.sqa.na131.tbsite.net(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0WNi9tts_1736934655 cluster:ay36) by smtp.aliyun-inc.com; Wed, 15 Jan 2025 17:50:57 +0800 From: Gao Xiang To: stable@vger.kernel.org, Greg Kroah-Hartman , Sasha Levin Cc: linux-erofs@lists.ozlabs.org, LKML Subject: [PATCH 6.1.y 2/2] erofs: handle NONHEAD !delta[1] lclusters gracefully Date: Wed, 15 Jan 2025 17:50:48 +0800 Message-ID: <20250115095048.2845612-2-hsiangkao@linux.alibaba.com> X-Mailer: git-send-email 2.43.5 In-Reply-To: <20250115095048.2845612-1-hsiangkao@linux.alibaba.com> References: <20250115095048.2845612-1-hsiangkao@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 commit 0bc8061ffc733a0a246b8689b2d32a3e9204f43c upstream. syzbot reported a WARNING in iomap_iter_done: iomap_fiemap+0x73b/0x9b0 fs/iomap/fiemap.c:80 ioctl_fiemap fs/ioctl.c:220 [inline] Generally, NONHEAD lclusters won't have delta[1]==0, except for crafted images and filesystems created by pre-1.0 mkfs versions. Previously, it would immediately bail out if delta[1]==0, which led to inadequate decompressed lengths (thus FIEMAP is impacted). Treat it as delta[1]=1 to work around these legacy mkfs versions. `lclusterbits > 14` is illegal for compact indexes, error out too. Reported-by: syzbot+6c0b301317aa0156f9eb@syzkaller.appspotmail.com Closes: https://lore.kernel.org/r/67373c0c.050a0220.2a2fcc.0079.GAE@google.com Tested-by: syzbot+6c0b301317aa0156f9eb@syzkaller.appspotmail.com Fixes: d95ae5e25326 ("erofs: add support for the full decompressed length") Fixes: 001b8ccd0650 ("erofs: fix compact 4B support for 16k block size") CVE: CVE-2024-53234 Link: https://lore.kernel.org/r/20241115173651.3339514-1-hsiangkao@linux.alibaba.com Signed-off-by: Gao Xiang --- fs/erofs/zmap.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c index 046eaaf16dad..2cd70cf4c8b2 100644 --- a/fs/erofs/zmap.c +++ b/fs/erofs/zmap.c @@ -256,7 +256,7 @@ static int compacted_load_cluster_from_disk(struct z_erofs_maprecorder *m, unsigned int amortizedshift; erofs_off_t pos; - if (lcn >= totalidx) + if (lcn >= totalidx || vi->z_logical_clusterbits > 14) return -EINVAL; m->lcn = lcn; @@ -441,7 +441,7 @@ static int z_erofs_get_extent_decompressedlen(struct z_erofs_maprecorder *m) u64 lcn = m->lcn, headlcn = map->m_la >> lclusterbits; int err; - do { + while (1) { /* handle the last EOF pcluster (no next HEAD lcluster) */ if ((lcn << lclusterbits) >= inode->i_size) { map->m_llen = inode->i_size - map->m_la; @@ -453,14 +453,16 @@ static int z_erofs_get_extent_decompressedlen(struct z_erofs_maprecorder *m) return err; if (m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD) { - DBG_BUGON(!m->delta[1] && - m->clusterofs != 1 << lclusterbits); + /* work around invalid d1 generated by pre-1.0 mkfs */ + if (unlikely(!m->delta[1])) { + m->delta[1] = 1; + DBG_BUGON(1); + } } else if (m->type == Z_EROFS_LCLUSTER_TYPE_PLAIN || m->type == Z_EROFS_LCLUSTER_TYPE_HEAD1 || m->type == Z_EROFS_LCLUSTER_TYPE_HEAD2) { - /* go on until the next HEAD lcluster */ if (lcn != headlcn) - break; + break; /* ends at the next HEAD lcluster */ m->delta[1] = 1; } else { erofs_err(inode->i_sb, "unknown type %u @ lcn %llu of nid %llu", @@ -469,8 +471,7 @@ static int z_erofs_get_extent_decompressedlen(struct z_erofs_maprecorder *m) return -EOPNOTSUPP; } lcn += m->delta[1]; - } while (m->delta[1]); - + } map->m_llen = (lcn << lclusterbits) + m->clusterofs - map->m_la; return 0; } -- 2.43.5