[f2fs-dev] [PATCH] f2fs: fix a bug when using namehash to locate dentry bucket

From: Shuoran Liu
Date: Thu Aug 25 2016 - 08:42:36 EST


In the following scenario,

1) we don't have the key and doing a lookup for encrypted file,
2) and the encrypted filename is big name

we should use fname->hash as name hash value instead of what is
calculated by fname->disk_name. Because in such case,
fname->disk_name is empty.
---
fs/f2fs/dir.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index 9054aea..b3e6f7f 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -172,7 +172,10 @@ static struct f2fs_dir_entry *find_in_level(struct inode *dir,
int max_slots;
f2fs_hash_t namehash;

- namehash = f2fs_dentry_hash(&name);
+ if(fname->hash)
+ namehash = cpu_to_le32(fname->hash);
+ else
+ namehash = f2fs_dentry_hash(&name);

nbucket = dir_buckets(level, F2FS_I(dir)->i_dir_level);
nblock = bucket_blocks(level);
--
1.9.1