[PATCH] ubifs: Correctly handle 0 value hashes in ubifs_lookup()

From: Richard Weinberger
Date: Mon Apr 24 2017 - 17:31:59 EST


Use fname_name(&nm) == NULL to detect whether a double hash
lookup should be performed instead of checking for nm.hash
being non-zero. zero is a valid hash value.

Fixes: f4f61d2cc6d8 ("ubifs: Implement encrypted filenames")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Richard Weinberger <richard@xxxxxx>
---
fs/ubifs/dir.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index b777bddaa1dd..ff77a0aa2f2b 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -249,9 +249,8 @@ static struct dentry *ubifs_lookup(struct inode *dir, struct dentry *dentry,
goto out_fname;
}

- if (nm.hash) {
+ if (fname_name(&nm) == NULL) {
ubifs_assert(fname_len(&nm) == 0);
- ubifs_assert(fname_name(&nm) == NULL);
dent_key_init_hash(c, &key, dir->i_ino, nm.hash);
err = ubifs_tnc_lookup_dh(c, &key, dent, nm.minor_hash);
} else {
--
2.7.3