[PATCH] ext4: fix to check return value of freeze_bdev() in ext4_shutdown()

[Chao Yu]

freeze_bdev() can fail due to a lot of reasons, it needs to check its
reason before later process.

Fixes: 783d94854499 ("ext4: add EXT4_IOC_GOINGDOWN ioctl")
Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
---
 fs/ext4/ioctl.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index f9a430152063..55be1b8a6360 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -797,6 +797,7 @@ static int ext4_shutdown(struct super_block *sb, unsigned long arg)
 {
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
 	__u32 flags;
+	int ret;
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
@@ -815,7 +816,9 @@ static int ext4_shutdown(struct super_block *sb, unsigned long arg)
 
 	switch (flags) {
 	case EXT4_GOING_FLAGS_DEFAULT:
-		freeze_bdev(sb->s_bdev);
+		ret = freeze_bdev(sb->s_bdev);
+		if (ret)
+			return ret;
 		set_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
 		thaw_bdev(sb->s_bdev);
 		break;
-- 
2.40.1