userns: Convert quota netlink aka quota_send_warning

Modify quota_send_warning to take struct kqid instead a type and
identifier pair.

When sending netlink broadcasts always convert uids and quota
identifiers into the intial user namespace.  There is as yet no way to
send a netlink broadcast message with different contents to receivers
in different namespaces, so for the time being just map all of the
identifiers into the initial user namespace which preserves the
current behavior.

Change the callers of quota_send_warning in gfs2, xfs and dquot
to generate a struct kqid to pass to quota send warning.  When
all of the user namespaces convesions are complete a struct kqid
values will be availbe without need for conversion, but a conversion
is needed now to avoid needing to convert everything at once.

Cc: Ben Myers <bpm@sgi.com>
Cc: Alex Elder <elder@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

2 files changed, 7 insertions, 5 deletions

diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index 7714b169d646..80d337822462 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -1236,7 +1236,7 @@ static void flush_warnings(struct dquot_warn *warn)
 #ifdef CONFIG_PRINT_QUOTA_WARNING
                 print_warning(&warn[i]);
 #endif
-                quota_send_warning(warn[i].w_dq_type, warn[i].w_dq_id,
+                quota_send_warning(make_kqid(&init_user_ns, warn[i].w_dq_type, warn[i].w_dq_id),
                                    warn[i].w_sb->s_dev, warn[i].w_type);
         }
 }
diff --git a/fs/quota/netlink.c b/fs/quota/netlink.c
index d67908b407d9..16e8abb7709b 100644
--- a/fs/quota/netlink.c
+++ b/fs/quota/netlink.c
@@ -30,7 +30,7 @@ static struct genl_family quota_genl_family = {
  *
  */
 
-void quota_send_warning(short type, unsigned int id, dev_t dev,
+void quota_send_warning(struct kqid qid, dev_t dev,
                         const char warntype)
 {
         static atomic_t seq;
@@ -56,10 +56,11 @@ void quota_send_warning(short type, unsigned int id, dev_t dev,
                   "VFS: Cannot store netlink header in quota warning.\n");
                 goto err_out;
         }
-        ret = nla_put_u32(skb, QUOTA_NL_A_QTYPE, type);
+        ret = nla_put_u32(skb, QUOTA_NL_A_QTYPE, qid.type);
         if (ret)
                 goto attr_err_out;
-        ret = nla_put_u64(skb, QUOTA_NL_A_EXCESS_ID, id);
+        ret = nla_put_u64(skb, QUOTA_NL_A_EXCESS_ID,
+                          from_kqid_munged(&init_user_ns, qid));
         if (ret)
                 goto attr_err_out;
         ret = nla_put_u32(skb, QUOTA_NL_A_WARNING, warntype);
@@ -71,7 +72,8 @@ void quota_send_warning(short type, unsigned int id, dev_t dev,
         ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MINOR, MINOR(dev));
         if (ret)
                 goto attr_err_out;
-        ret = nla_put_u64(skb, QUOTA_NL_A_CAUSED_ID, current_uid());
+        ret = nla_put_u64(skb, QUOTA_NL_A_CAUSED_ID,
+                          from_kuid_munged(&init_user_ns, current_uid()));
         if (ret)
                 goto attr_err_out;
         genlmsg_end(skb, msg_head);