GFS2: Fix permissions checking for setflags ioctl()

We should be checking for the ownership of the file for which
flags are being set, rather than just for write access.

Reported-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index e6dd2ae..b20bfcc 100644 (file)
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -218,6 +218,11 @@ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask)
        if (error)
                goto out_drop_write;
 
+       error = -EACCES;
+       if (!is_owner_or_cap(inode))
+               goto out;
+
+       error = 0;
        flags = ip->i_diskflags;
        new_flags = (flags & ~mask) | (reqflags & mask);
        if ((new_flags ^ flags) == 0)
@@ -275,8 +280,10 @@ static int gfs2_set_flags(struct file *filp, u32 __user *ptr)
 {
        struct inode *inode = filp->f_path.dentry->d_inode;
        u32 fsflags, gfsflags;
+
        if (get_user(fsflags, ptr))
                return -EFAULT;
+
        gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags);
        if (!S_ISDIR(inode->i_mode)) {
                if (gfsflags & GFS2_DIF_INHERIT_JDATA)