gfs2: Call unlock_new_inode before d_instantiate

As Neil Brown describes in detail in the link referenced below, new
inodes must be unlocked before they can be instantiated.

An even better fix is to use d_instantiate_new(), which combines
d_instantiate() and unlock_new_inode().

Fixes: 3d36e57ff768 ("gfs2: gfs2_create_inode rework")
Reported-by: syzbot+0ea5108a1f5fb4fcc2d8@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-fsdevel/177153754005.8396.8777398743501764194@noble.neil.brown.name/
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 8344040ecaf79e1391c15e579e135ba495ce663f..e9bf4879c07f7335f8e53938b44be21209fee4fd 100644 (file)
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -892,7 +892,7 @@ retry:
                goto fail_gunlock4;
 
        mark_inode_dirty(inode);
-       d_instantiate(dentry, inode);
+       d_instantiate_new(dentry, inode);
        /* After instantiate, errors should result in evict which will destroy
         * both inode and iopen glocks properly. */
        if (file) {
@@ -904,7 +904,6 @@ retry:
        gfs2_glock_dq_uninit(&gh);
        gfs2_glock_put(io_gl);
        gfs2_qa_put(dip);
-       unlock_new_inode(inode);
        return error;
 
 fail_gunlock4: