[PATCH] drivers/staging/exfat: Ensure we unlock upon error in ffsReadFile

[Davidlohr Bueso]

The call was not releasing the mutex upon error.

Reported-by: kbuild test robot <lkp at intel.com>
Reported-by: Julia Lawall <julia.lawall at lip6.fr>
Signed-off-by: Davidlohr Bueso <dave at stgolabs.net>
---
 drivers/staging/exfat/exfat_super.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/exfat/exfat_super.c b/drivers/staging/exfat/exfat_super.c
index e9e9868cae85..02dcfe06fc4f 100644
--- a/drivers/staging/exfat/exfat_super.c
+++ b/drivers/staging/exfat/exfat_super.c
@@ -742,8 +742,10 @@ static int ffsReadFile(struct inode *inode, struct file_id_t *fid, void *buffer,
 
 			while (clu_offset > 0) {
 				/* clu = FAT_read(sb, clu); */
-				if (FAT_read(sb, clu, &clu) == -1)
-					return FFS_MEDIAERR;
+				if (FAT_read(sb, clu, &clu) == -1) {
+					ret = FFS_MEDIAERR;
+					goto out;
+				}
 
 				clu_offset--;
 			}
-- 
2.16.4