[PATCH] fs/ntfs3: reject FS_IOC_SETFSLABEL on readonly mounts

From: Baolin Liu <[email protected]>

FS_IOC_SETFSLABEL does not check for readonly mounts and
can report success without persisting the label change.

Return -EROFS on readonly mounts.

Fixes: 21dc07ac9c25 ("ntfs3: add FS_IOC_SETFSLABEL ioctl")
Signed-off-by: Baolin Liu <[email protected]>
---
 fs/ntfs3/file.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c
index b041639ab406..f43baa46ec5c 100644
--- a/fs/ntfs3/file.c
+++ b/fs/ntfs3/file.c
@@ -105,6 +105,9 @@ static int ntfs_ioctl_set_volume_label(struct ntfs_sb_info *sbi, u8 __user *buf)
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
 
+	if (sb_rdonly(sbi->sb))
+		return -EROFS;
+
 	if (copy_from_user(user, buf, FSLABEL_MAX))
 		return -EFAULT;
 
-- 
2.51.0