[PATCH] f2fs: fix to avoid corruption during inline conversion

From: Chao Yu
Date: Tue Aug 20 2019 - 10:35:26 EST


From: Chao Yu <yuchao0@xxxxxxxxxx>

- f2fs_setattr
- truncate_setsize (expand i_size)
- f2fs_convert_inline_inode
- f2fs_convert_inline_page
- f2fs_reserve_block
- f2fs_get_node_info failed

Once we fail in above path, inline flag will remain, however
- we've reserved one block at inode.i_addr[0]
- i_size has expanded

Fix error path to avoid inode corruption.

Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
---
fs/f2fs/file.c | 8 ++++++--
fs/f2fs/inline.c | 1 +
2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 2284ec706a40..05d60082da3a 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -812,7 +812,8 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
}

if (attr->ia_valid & ATTR_SIZE) {
- bool to_smaller = (attr->ia_size <= i_size_read(inode));
+ loff_t old_size = i_size_read(inode);
+ bool to_smaller = (attr->ia_size <= old_size);

down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
down_write(&F2FS_I(inode)->i_mmap_sem);
@@ -835,8 +836,11 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
/* should convert inline inode here */
if (!f2fs_may_inline_data(inode)) {
err = f2fs_convert_inline_inode(inode);
- if (err)
+ if (err) {
+ /* recover old i_size */
+ i_size_write(inode, old_size);
return err;
+ }
}
inode->i_mtime = inode->i_ctime = current_time(inode);
}
diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
index 78d6ebe165cd..16ebdd4d1f2c 100644
--- a/fs/f2fs/inline.c
+++ b/fs/f2fs/inline.c
@@ -131,6 +131,7 @@ int f2fs_convert_inline_page(struct dnode_of_data *dn, struct page *page)

err = f2fs_get_node_info(fio.sbi, dn->nid, &ni);
if (err) {
+ f2fs_truncate_data_blocks_range(dn, 1);
f2fs_put_dnode(dn);
return err;
}
--
2.22.0