From: Gao Xiang <gaoxiang25@xxxxxxxxxx> This patch fixes integer overflow on multiplication of 32-bit `lcn' in z_erofs_map_blocks_iter. Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx> Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx> Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx> --- drivers/staging/erofs/unzip_vle.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/staging/erofs/unzip_vle.c b/drivers/staging/erofs/unzip_vle.c index e31393a14e0d..dab892157e51 100644 --- a/drivers/staging/erofs/unzip_vle.c +++ b/drivers/staging/erofs/unzip_vle.c @@ -1513,7 +1513,7 @@ static erofs_off_t vle_get_logical_extent_head( *flags ^= EROFS_MAP_ZIPPED; case Z_EROFS_VLE_CLUSTER_TYPE_HEAD: /* clustersize should be a power of two */ - ofs = ((unsigned long long)lcn << clusterbits) + + ofs = ((u64)lcn << clusterbits) + (le16_to_cpu(di->di_clusterofs) & (clustersize - 1)); *pcn = le32_to_cpu(di->di_u.blkaddr); break; @@ -1595,7 +1595,7 @@ int z_erofs_map_blocks_iter(struct inode *inode, /* by default, compressed */ map->m_flags |= EROFS_MAP_ZIPPED; - end = (u64)(lcn + 1) * clustersize; + end = ((u64)lcn + 1) * clustersize; cluster_type = vle_cluster_type(di); @@ -1611,7 +1611,7 @@ int z_erofs_map_blocks_iter(struct inode *inode, } if (ofs_rem > logical_cluster_ofs) { - ofs = lcn * clustersize | logical_cluster_ofs; + ofs = (u64)lcn * clustersize | logical_cluster_ofs; pcn = le32_to_cpu(di->di_u.blkaddr); break; } @@ -1623,7 +1623,7 @@ int z_erofs_map_blocks_iter(struct inode *inode, err = -EIO; goto unmap_out; } - end = (lcn-- * clustersize) | logical_cluster_ofs; + end = ((u64)lcn-- * clustersize) | logical_cluster_ofs; /* fallthrough */ case Z_EROFS_VLE_CLUSTER_TYPE_NONHEAD: /* get the correspoinding first chunk */ -- 2.18.0 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel