[Cluster-devel] [PATCH] GFS2: Set s_mode before parsing mount options

[Cluster-devel] [PATCH] GFS2: Set s_mode before parsing mount options

[Andrew Price]

In the generic mount_bdev() function, deactivate_locked_super() is
called after the fill_super() call fails, at which point s_mode has been
set. kill_block_super() expects this and dumps a warning when
FMODE_EXCL is not set in s_mode.

In gfs2_mount() we call deactivate_locked_super() on failure of
gfs2_mount_args(), at which point s_mode has not yet been set. This
causes kill_block_super() to dump a stack trace when gfs2 fails to mount
with invalid options. Set s_mode earlier in gfs2_mount() to avoid that.

Signed-off-by: Andrew Price <anprice@redhat.com>
---
 fs/gfs2/ops_fstype.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 02586e7..baab99b 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -1291,6 +1291,9 @@ static struct dentry *gfs2_mount(struct file_system_type *fs_type, int flags,
 		up_write(&s->s_umount);
 		blkdev_put(bdev, mode);
 		down_write(&s->s_umount);
+	} else {
+		/* s_mode must be set before deactivate_locked_super calls */
+		s->s_mode = mode;
 	}
 
 	memset(&args, 0, sizeof(args));
@@ -1314,7 +1317,6 @@ static struct dentry *gfs2_mount(struct file_system_type *fs_type, int flags,
 	} else {
 		char b[BDEVNAME_SIZE];
 
-		s->s_mode = mode;
 		strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id));
 		sb_set_blocksize(s, block_size(bdev));
 		error = fill_super(s, &args, flags & MS_SILENT ? 1 : 0);
-- 
2.4.3

[Cluster-devel] [PATCH] GFS2: Set s_mode before parsing mount options

[Bob Peterson]

----- Original Message -----
> In the generic mount_bdev() function, deactivate_locked_super() is
> called after the fill_super() call fails, at which point s_mode has been
> set. kill_block_super() expects this and dumps a warning when
> FMODE_EXCL is not set in s_mode.
> 
> In gfs2_mount() we call deactivate_locked_super() on failure of
> gfs2_mount_args(), at which point s_mode has not yet been set. This
> causes kill_block_super() to dump a stack trace when gfs2 fails to mount
> with invalid options. Set s_mode earlier in gfs2_mount() to avoid that.
> 
> Signed-off-by: Andrew Price <anprice@redhat.com>
> ---
>  fs/gfs2/ops_fstype.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
> index 02586e7..baab99b 100644
> --- a/fs/gfs2/ops_fstype.c
> +++ b/fs/gfs2/ops_fstype.c
> @@ -1291,6 +1291,9 @@ static struct dentry *gfs2_mount(struct
> file_system_type *fs_type, int flags,
>  		up_write(&s->s_umount);
>  		blkdev_put(bdev, mode);
>  		down_write(&s->s_umount);
> +	} else {
> +		/* s_mode must be set before deactivate_locked_super calls */
> +		s->s_mode = mode;
>  	}
>  
>  	memset(&args, 0, sizeof(args));
> @@ -1314,7 +1317,6 @@ static struct dentry *gfs2_mount(struct
> file_system_type *fs_type, int flags,
>  	} else {
>  		char b[BDEVNAME_SIZE];
>  
> -		s->s_mode = mode;
>  		strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id));
>  		sb_set_blocksize(s, block_size(bdev));
>  		error = fill_super(s, &args, flags & MS_SILENT ? 1 : 0);
> --
> 2.4.3
> 

Hi,

Thanks. This is now applied to the for-next branch of the linux-gfs2 tree:

https://git.kernel.org/cgit/linux/kernel/git/gfs2/linux-gfs2.git/commit/fs/gfs2?h=for-next&id=6de20eb0dee4c802d9d228d6c08d00386e172e52

Regards,

Bob Peterson
Red Hat File Systems