[PATCH] r/o bind mounts: elevate write count for ioctls()
Some ioctl()s can cause writes to the filesystem. Take these, and make them
use mnt_want/drop_write() instead.
[AV: updated]
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/ocfs2/ioctl.c b/fs/ocfs2/ioctl.c
index b413166..7b142f0 100644
--- a/fs/ocfs2/ioctl.c
+++ b/fs/ocfs2/ioctl.c
@@ -60,10 +60,6 @@
goto bail;
}
- status = -EROFS;
- if (IS_RDONLY(inode))
- goto bail_unlock;
-
status = -EACCES;
if (!is_owner_or_cap(inode))
goto bail_unlock;
@@ -134,8 +130,13 @@
if (get_user(flags, (int __user *) arg))
return -EFAULT;
- return ocfs2_set_inode_attr(inode, flags,
+ status = mnt_want_write(filp->f_path.mnt);
+ if (status)
+ return status;
+ status = ocfs2_set_inode_attr(inode, flags,
OCFS2_FL_MODIFIABLE);
+ mnt_drop_write(filp->f_path.mnt);
+ return status;
case OCFS2_IOC_RESVSP:
case OCFS2_IOC_RESVSP64:
case OCFS2_IOC_UNRESVSP: