Re: [PATCH review 22/85] ocfs2: convert between kuids and kgids andDLM locks

From: Joel Becker
Date: Thu Feb 14 2013 - 03:34:31 EST


On Wed, Feb 13, 2013 at 09:51:11AM -0800, Eric W. Biederman wrote:
> From: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
>
> Convert between uid and gids stored in the on the wire format of dlm
> locks aka struct ocfs2_meta_lvb and kuids and kgids stored in
> inode->i_uid and inode->i_gid.
>
> Cc: Mark Fasheh <mfasheh@xxxxxxxx>
> Cc: Joel Becker <jlbec@xxxxxxxxxxxx>
> Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
> ---
> fs/ocfs2/dlmglue.c | 8 ++++----
> 1 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
> index 4f7795f..f99af1c 100644
> --- a/fs/ocfs2/dlmglue.c
> +++ b/fs/ocfs2/dlmglue.c
> @@ -2045,8 +2045,8 @@ static void __ocfs2_stuff_meta_lvb(struct inode *inode)
> lvb->lvb_version = OCFS2_LVB_VERSION;
> lvb->lvb_isize = cpu_to_be64(i_size_read(inode));
> lvb->lvb_iclusters = cpu_to_be32(oi->ip_clusters);
> - lvb->lvb_iuid = cpu_to_be32(inode->i_uid);
> - lvb->lvb_igid = cpu_to_be32(inode->i_gid);
> + lvb->lvb_iuid = cpu_to_be32(i_uid_read(inode));
> + lvb->lvb_igid = cpu_to_be32(i_gid_read(inode));
> lvb->lvb_imode = cpu_to_be16(inode->i_mode);
> lvb->lvb_inlink = cpu_to_be16(inode->i_nlink);
> lvb->lvb_iatime_packed =
> @@ -2095,8 +2095,8 @@ static void ocfs2_refresh_inode_from_lvb(struct inode *inode)
> else
> inode->i_blocks = ocfs2_inode_sector_count(inode);
>
> - inode->i_uid = be32_to_cpu(lvb->lvb_iuid);
> - inode->i_gid = be32_to_cpu(lvb->lvb_igid);
> + i_uid_write(inode, be32_to_cpu(lvb->lvb_iuid));
> + i_gid_write(inode, be32_to_cpu(lvb->lvb_igid));
> inode->i_mode = be16_to_cpu(lvb->lvb_imode);
> set_nlink(inode, be16_to_cpu(lvb->lvb_inlink));
> ocfs2_unpack_timespec(&inode->i_atime,

What does this do if two machines with different user namespaces
communicate. I think that things go very wrong. Perhaps right now,
when ocfs2 is tied to init_user_namespace, we're OK. But as soon as two
systems can be in different namespaces, we are broken.

Joel

> --
> 1.7.5.4
>

--

"I think it would be a good idea."
- Mahatma Ghandi, when asked what he thought of Western
civilization

http://www.jlbec.org/
jlbec@xxxxxxxxxxxx
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