The current algorithm sanity checks do not properly apply to new encoded extents.
Unify the algorithm format check with Z_EROFS_COMPRESSION_MAX and ensure consistency with sbi->available_compr_algs. Reported-by: syzbot+5a398eb460ddaa6f2...@syzkaller.appspotmail.com Closes: https://lore.kernel.org/r/68a8bd20.050a0220.37038e.005a....@google.com Fixes: 1d191b4ca51d ("erofs: implement encoded extent metadata") Thanks-to: Edward Adam Davis <eada...@qq.com> Signed-off-by: Gao Xiang <hsiang...@linux.alibaba.com> --- fs/erofs/zmap.c | 66 +++++++++++++++++++++++++++---------------------- 1 file changed, 36 insertions(+), 30 deletions(-) diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c index a93efd95c555..d5755da33235 100644 --- a/fs/erofs/zmap.c +++ b/fs/erofs/zmap.c @@ -394,10 +394,10 @@ static int z_erofs_map_blocks_fo(struct inode *inode, .map = map, .in_mbox = erofs_inode_in_metabox(inode), }; - int err = 0; - unsigned int endoff, afmt; + unsigned int endoff; unsigned long initial_lcn; unsigned long long ofs, end; + int err; ofs = flags & EROFS_GET_BLOCKS_FINDTAIL ? inode->i_size - 1 : map->m_la; if (fragment && !(flags & EROFS_GET_BLOCKS_FINDTAIL) && @@ -482,20 +482,15 @@ static int z_erofs_map_blocks_fo(struct inode *inode, err = -EFSCORRUPTED; goto unmap_out; } - afmt = vi->z_advise & Z_EROFS_ADVISE_INTERLACED_PCLUSTER ? - Z_EROFS_COMPRESSION_INTERLACED : - Z_EROFS_COMPRESSION_SHIFTED; + if (vi->z_advise & Z_EROFS_ADVISE_INTERLACED_PCLUSTER) + map->m_algorithmformat = Z_EROFS_COMPRESSION_INTERLACED; + else + map->m_algorithmformat = Z_EROFS_COMPRESSION_SHIFTED; + } else if (m.headtype == Z_EROFS_LCLUSTER_TYPE_HEAD2) { + map->m_algorithmformat = vi->z_algorithmtype[1]; } else { - afmt = m.headtype == Z_EROFS_LCLUSTER_TYPE_HEAD2 ? - vi->z_algorithmtype[1] : vi->z_algorithmtype[0]; - if (!(EROFS_I_SB(inode)->available_compr_algs & (1 << afmt))) { - erofs_err(sb, "inconsistent algorithmtype %u for nid %llu", - afmt, vi->nid); - err = -EFSCORRUPTED; - goto unmap_out; - } + map->m_algorithmformat = vi->z_algorithmtype[0]; } - map->m_algorithmformat = afmt; if ((flags & EROFS_GET_BLOCKS_FIEMAP) || ((flags & EROFS_GET_BLOCKS_READMORE) && @@ -626,9 +621,9 @@ static int z_erofs_fill_inode(struct inode *inode, struct erofs_map_blocks *map) { struct erofs_inode *const vi = EROFS_I(inode); struct super_block *const sb = inode->i_sb; - int err, headnr; - erofs_off_t pos; struct z_erofs_map_header *h; + erofs_off_t pos; + int err = 0; if (test_bit(EROFS_I_Z_INITED_BIT, &vi->flags)) { /* @@ -642,7 +637,6 @@ static int z_erofs_fill_inode(struct inode *inode, struct erofs_map_blocks *map) if (wait_on_bit_lock(&vi->flags, EROFS_I_BL_Z_BIT, TASK_KILLABLE)) return -ERESTARTSYS; - err = 0; if (test_bit(EROFS_I_Z_INITED_BIT, &vi->flags)) goto out_unlock; @@ -679,15 +673,6 @@ static int z_erofs_fill_inode(struct inode *inode, struct erofs_map_blocks *map) else if (vi->z_advise & Z_EROFS_ADVISE_INLINE_PCLUSTER) vi->z_idata_size = le16_to_cpu(h->h_idata_size); - headnr = 0; - if (vi->z_algorithmtype[0] >= Z_EROFS_COMPRESSION_MAX || - vi->z_algorithmtype[++headnr] >= Z_EROFS_COMPRESSION_MAX) { - erofs_err(sb, "unknown HEAD%u format %u for nid %llu, please upgrade kernel", - headnr + 1, vi->z_algorithmtype[headnr], vi->nid); - err = -EOPNOTSUPP; - goto out_unlock; - } - if (!erofs_sb_has_big_pcluster(EROFS_SB(sb)) && vi->z_advise & (Z_EROFS_ADVISE_BIG_PCLUSTER_1 | Z_EROFS_ADVISE_BIG_PCLUSTER_2)) { @@ -726,6 +711,29 @@ static int z_erofs_fill_inode(struct inode *inode, struct erofs_map_blocks *map) return err; } +static int z_erofs_map_sanity_check(struct inode *inode, + struct erofs_map_blocks *map) +{ + struct erofs_sb_info *sbi = EROFS_I_SB(inode); + + if (!(map->m_flags & EROFS_MAP_ENCODED)) + return 0; + if (unlikely(map->m_algorithmformat >= Z_EROFS_COMPRESSION_MAX)) { + erofs_err(inode->i_sb, "unknown algorithm %d @ pos %llu for nid %llu, please upgrade kernel", + map->m_algorithmformat, map->m_la, EROFS_I(inode)->nid); + return -EOPNOTSUPP; + } + if (unlikely(!(sbi->available_compr_algs & (1 << map->m_algorithmformat)))) { + erofs_err(inode->i_sb, "inconsistent algorithmtype %u for nid %llu", + map->m_algorithmformat, EROFS_I(inode)->nid); + return -EFSCORRUPTED; + } + if (unlikely(map->m_plen > Z_EROFS_PCLUSTER_MAX_SIZE || + map->m_llen > Z_EROFS_PCLUSTER_MAX_DSIZE)) + return -EOPNOTSUPP; + return 0; +} + int z_erofs_map_blocks_iter(struct inode *inode, struct erofs_map_blocks *map, int flags) { @@ -746,10 +754,8 @@ int z_erofs_map_blocks_iter(struct inode *inode, struct erofs_map_blocks *map, else err = z_erofs_map_blocks_fo(inode, map, flags); } - if (!err && (map->m_flags & EROFS_MAP_ENCODED) && - unlikely(map->m_plen > Z_EROFS_PCLUSTER_MAX_SIZE || - map->m_llen > Z_EROFS_PCLUSTER_MAX_DSIZE)) - err = -EOPNOTSUPP; + if (!err) + err = z_erofs_map_sanity_check(inode, map); if (err) map->m_llen = 0; } -- 2.43.5
