[PATCH v2 3/8] staging: erofs: complete error handing of z_erofs_map_blocks_iter

From: Gao Xiang
Date: Tue Sep 18 2018 - 10:26:38 EST


This patch completes error handing of z_erofs_map_blocks_iter
and vle_get_logical_extent_head, including no memory and
io error cases.

Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx>
---
drivers/staging/erofs/unzip_vle.c | 35 ++++++++++++++++++++++++++---------
1 file changed, 26 insertions(+), 9 deletions(-)

diff --git a/drivers/staging/erofs/unzip_vle.c b/drivers/staging/erofs/unzip_vle.c
index 1e89ff6..94c35b8 100644
--- a/drivers/staging/erofs/unzip_vle.c
+++ b/drivers/staging/erofs/unzip_vle.c
@@ -1500,7 +1500,11 @@ struct vle_map_blocks_iter_ctx {
unlock_page(mpage);
put_page(mpage);

- mpage = erofs_get_meta_page_nofail(ctx->sb, mblk, false);
+ mpage = erofs_get_meta_page(ctx->sb, mblk, false);
+ if (IS_ERR(mpage)) {
+ *ctx->mpage_ret = NULL;
+ return PTR_ERR(mpage);
+ }
*ctx->mpage_ret = mpage;
*ctx->kaddr_ret = kmap_atomic(mpage);
}
@@ -1511,9 +1515,12 @@ struct vle_map_blocks_iter_ctx {
switch (cluster_type) {
case Z_EROFS_VLE_CLUSTER_TYPE_NONHEAD:
delta0 = le16_to_cpu(di->di_u.delta[0]);
- DBG_BUGON(!delta0);
- DBG_BUGON(lcn < delta0);
-
+ if (unlikely(!delta0 || delta0 > lcn)) {
+ errln("invalid NONHEAD dl0 %u at lcn %u of nid %llu",
+ delta0, lcn, EROFS_V(ctx->inode)->nid);
+ DBG_BUGON(1);
+ return -EIO;
+ }
return vle_get_logical_extent_head(ctx,
lcn - delta0, ofs, pblk, flags);
case Z_EROFS_VLE_CLUSTER_TYPE_PLAIN:
@@ -1526,7 +1533,10 @@ struct vle_map_blocks_iter_ctx {
*pblk = le32_to_cpu(di->di_u.blkaddr);
break;
default:
- BUG_ON(1);
+ errln("unknown cluster type %u at lcn %u of nid %llu",
+ cluster_type, lcn, EROFS_V(ctx->inode)->nid);
+ DBG_BUGON(1);
+ return -EIO;
}
return 0;
}
@@ -1583,7 +1593,11 @@ int z_erofs_map_blocks_iter(struct inode *inode,
if (mpage != NULL)
put_page(mpage);

- mpage = erofs_get_meta_page_nofail(ctx.sb, mblk, false);
+ mpage = erofs_get_meta_page(ctx.sb, mblk, false);
+ if (IS_ERR(mpage)) {
+ err = PTR_ERR(mpage);
+ goto out;
+ }
*mpage_ret = mpage;
} else {
lock_page(mpage);
@@ -1646,8 +1660,11 @@ int z_erofs_map_blocks_iter(struct inode *inode,
&pblk, &map->m_flags);
mpage = *mpage_ret;

- if (unlikely(err))
- goto unmap_out;
+ if (unlikely(err)) {
+ if (mpage)
+ goto unmap_out;
+ goto out;
+ }
break;
default:
errln("unknown cluster type %u at offset %llu of nid %llu",
@@ -1671,7 +1688,7 @@ int z_erofs_map_blocks_iter(struct inode *inode,
map->m_llen, map->m_plen, map->m_flags);

/* aggressively BUG_ON iff CONFIG_EROFS_FS_DEBUG is on */
- DBG_BUGON(err < 0);
+ DBG_BUGON(err < 0 && err != -ENOMEM);
return err;
}

--
1.9.1