From: Chao Yu Date: Tue, 8 Jul 2025 11:09:28 +0000 (+0800) Subject: erofs: do sanity check on m->type in z_erofs_load_compact_lcluster() X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1a5223c182fdb3bb3c0ca85cec101c740f685ab6;p=thirdparty%2Fkernel%2Flinux.git erofs: do sanity check on m->type in z_erofs_load_compact_lcluster() All below functions will do sanity check on m->type, let's move sanity check to z_erofs_load_compact_lcluster() for cleanup. - z_erofs_map_blocks_fo - z_erofs_get_extent_compressedlen - z_erofs_get_extent_decompressedlen - z_erofs_extent_lookback Reviewed-by: Hongbo Li Signed-off-by: Chao Yu Reviewed-by: Gao Xiang Link: https://lore.kernel.org/r/20250708110928.3110375-1-chao@kernel.org Signed-off-by: Gao Xiang --- diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c index f1a15ff22147b..312ec54668aac 100644 --- a/fs/erofs/zmap.c +++ b/fs/erofs/zmap.c @@ -240,6 +240,13 @@ static int z_erofs_load_compact_lcluster(struct z_erofs_maprecorder *m, static int z_erofs_load_lcluster_from_disk(struct z_erofs_maprecorder *m, unsigned int lcn, bool lookahead) { + if (m->type >= Z_EROFS_LCLUSTER_TYPE_MAX) { + erofs_err(m->inode->i_sb, "unknown type %u @ lcn %u of nid %llu", + m->type, lcn, EROFS_I(m->inode)->nid); + DBG_BUGON(1); + return -EOPNOTSUPP; + } + switch (EROFS_I(m->inode)->datalayout) { case EROFS_INODE_COMPRESSED_FULL: return z_erofs_load_full_lcluster(m, lcn); @@ -265,12 +272,7 @@ static int z_erofs_extent_lookback(struct z_erofs_maprecorder *m, if (err) return err; - if (m->type >= Z_EROFS_LCLUSTER_TYPE_MAX) { - erofs_err(sb, "unknown type %u @ lcn %lu of nid %llu", - m->type, lcn, vi->nid); - DBG_BUGON(1); - return -EOPNOTSUPP; - } else if (m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD) { + if (m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD) { lookback_distance = m->delta[0]; if (!lookback_distance) break; @@ -325,25 +327,18 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m, DBG_BUGON(lcn == initial_lcn && m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD); - if (m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD) { - if (m->delta[0] != 1) { - erofs_err(sb, "bogus CBLKCNT @ lcn %lu of nid %llu", lcn, vi->nid); - DBG_BUGON(1); - return -EFSCORRUPTED; - } - if (m->compressedblks) - goto out; - } else if (m->type < Z_EROFS_LCLUSTER_TYPE_MAX) { - /* - * if the 1st NONHEAD lcluster is actually PLAIN or HEAD type - * rather than CBLKCNT, it's a 1 block-sized pcluster. - */ - m->compressedblks = 1; - goto out; + if (m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD && m->delta[0] != 1) { + erofs_err(sb, "bogus CBLKCNT @ lcn %lu of nid %llu", lcn, vi->nid); + DBG_BUGON(1); + return -EFSCORRUPTED; } - erofs_err(sb, "cannot found CBLKCNT @ lcn %lu of nid %llu", lcn, vi->nid); - DBG_BUGON(1); - return -EFSCORRUPTED; + + /* + * if the 1st NONHEAD lcluster is actually PLAIN or HEAD type rather + * than CBLKCNT, it's a 1 block-sized pcluster. + */ + if (m->type != Z_EROFS_LCLUSTER_TYPE_NONHEAD || !m->compressedblks) + m->compressedblks = 1; out: m->map->m_plen = erofs_pos(sb, m->compressedblks); return 0; @@ -379,11 +374,6 @@ static int z_erofs_get_extent_decompressedlen(struct z_erofs_maprecorder *m) if (lcn != headlcn) 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", - m->type, lcn, vi->nid); - DBG_BUGON(1); - return -EOPNOTSUPP; } lcn += m->delta[1]; } @@ -428,44 +418,33 @@ static int z_erofs_map_blocks_fo(struct inode *inode, map->m_flags = EROFS_MAP_MAPPED | EROFS_MAP_ENCODED; end = (m.lcn + 1ULL) << lclusterbits; - switch (m.type) { - case Z_EROFS_LCLUSTER_TYPE_PLAIN: - case Z_EROFS_LCLUSTER_TYPE_HEAD1: - case Z_EROFS_LCLUSTER_TYPE_HEAD2: - if (endoff >= m.clusterofs) { - m.headtype = m.type; - map->m_la = (m.lcn << lclusterbits) | m.clusterofs; - /* - * For ztailpacking files, in order to inline data more - * effectively, special EOF lclusters are now supported - * which can have three parts at most. - */ - if (ztailpacking && end > inode->i_size) - end = inode->i_size; - break; - } - /* m.lcn should be >= 1 if endoff < m.clusterofs */ - if (!m.lcn) { - erofs_err(sb, "invalid logical cluster 0 at nid %llu", - vi->nid); - err = -EFSCORRUPTED; - goto unmap_out; + if (m.type != Z_EROFS_LCLUSTER_TYPE_NONHEAD && endoff >= m.clusterofs) { + m.headtype = m.type; + map->m_la = (m.lcn << lclusterbits) | m.clusterofs; + /* + * For ztailpacking files, in order to inline data more + * effectively, special EOF lclusters are now supported + * which can have three parts at most. + */ + if (ztailpacking && end > inode->i_size) + end = inode->i_size; + } else { + if (m.type != Z_EROFS_LCLUSTER_TYPE_NONHEAD) { + /* m.lcn should be >= 1 if endoff < m.clusterofs */ + if (!m.lcn) { + erofs_err(sb, "invalid logical cluster 0 at nid %llu", + vi->nid); + err = -EFSCORRUPTED; + goto unmap_out; + } + end = (m.lcn << lclusterbits) | m.clusterofs; + map->m_flags |= EROFS_MAP_FULL_MAPPED; + m.delta[0] = 1; } - end = (m.lcn << lclusterbits) | m.clusterofs; - map->m_flags |= EROFS_MAP_FULL_MAPPED; - m.delta[0] = 1; - fallthrough; - case Z_EROFS_LCLUSTER_TYPE_NONHEAD: /* get the corresponding first chunk */ err = z_erofs_extent_lookback(&m, m.delta[0]); if (err) goto unmap_out; - break; - default: - erofs_err(sb, "unknown type %u @ offset %llu of nid %llu", - m.type, ofs, vi->nid); - err = -EOPNOTSUPP; - goto unmap_out; } if (m.partialref) map->m_flags |= EROFS_MAP_PARTIAL_REF;