staging: erofs: fix vle_decompressed_index_clusterofs

This patch adds error handing code, and fixes a missing
endian conversion in vle_decompressed_index_clusterofs.

Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/erofs/unzip_vle.c b/drivers/staging/erofs/unzip_vle.c
index f597f07..e31393a 100644 (file)
--- a/drivers/staging/erofs/unzip_vle.c
+++ b/drivers/staging/erofs/unzip_vle.c
@@ -1419,24 +1419,24 @@ const struct address_space_operations z_erofs_vle_normalaccess_aops = {
 #define vle_cluster_type(di)   \
        __vle_cluster_type((di)->di_advise)
 
-static inline unsigned
-vle_compressed_index_clusterofs(unsigned clustersize,
-       struct z_erofs_vle_decompressed_index *di)
+static int
+vle_decompressed_index_clusterofs(unsigned int *clusterofs,
+                                 unsigned int clustersize,
+                                 struct z_erofs_vle_decompressed_index *di)
 {
-       debugln("%s, vle=%pK, advise=%x (type %u), clusterofs=%x blkaddr=%x",
-               __func__, di, di->di_advise, vle_cluster_type(di),
-               di->di_clusterofs, di->di_u.blkaddr);
-
        switch (vle_cluster_type(di)) {
        case Z_EROFS_VLE_CLUSTER_TYPE_NONHEAD:
+               *clusterofs = clustersize;
                break;
        case Z_EROFS_VLE_CLUSTER_TYPE_PLAIN:
        case Z_EROFS_VLE_CLUSTER_TYPE_HEAD:
-               return di->di_clusterofs;
+               *clusterofs = le16_to_cpu(di->di_clusterofs);
+               break;
        default:
-               BUG_ON(1);
+               DBG_BUGON(1);
+               return -EIO;
        }
-       return clustersize;
+       return 0;
 }
 
 static inline erofs_blk_t
@@ -1581,7 +1581,11 @@ int z_erofs_map_blocks_iter(struct inode *inode,
        debugln("%s, lcn %u e_blkaddr %u e_blkoff %u", __func__, lcn,
                e_blkaddr, vle_extent_blkoff(inode, lcn));
 
-       logical_cluster_ofs = vle_compressed_index_clusterofs(clustersize, di);
+       err = vle_decompressed_index_clusterofs(&logical_cluster_ofs,
+                                               clustersize, di);
+       if (unlikely(err))
+               goto unmap_out;
+
        if (!initial) {
                /* [walking mode] 'map' has been already initialized */
                map->m_llen += logical_cluster_ofs;