userns: Convert ext4 to user kuid/kgid where appropriate

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

1 files changed, 20 insertions, 14 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index c77b0bd2c711..07eaf565fdcb 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3630,6 +3630,8 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
         journal_t *journal = EXT4_SB(sb)->s_journal;
         long ret;
         int block;
+        uid_t i_uid;
+        gid_t i_gid;
 
         inode = iget_locked(sb, ino);
         if (!inode)
@@ -3645,12 +3647,14 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
                 goto bad_inode;
         raw_inode = ext4_raw_inode(&iloc);
         inode->i_mode = le16_to_cpu(raw_inode->i_mode);
-        inode->i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
-        inode->i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
+        i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low);
+        i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low);
         if (!(test_opt(inode->i_sb, NO_UID32))) {
-                inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
-                inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
+                i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
+                i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
         }
+        i_uid_write(inode, i_uid);
+        i_gid_write(inode, i_gid);
         set_nlink(inode, le16_to_cpu(raw_inode->i_links_count));
 
         ext4_clear_state_flags(ei);     /* Only relevant on 32-bit archs */
@@ -3870,6 +3874,8 @@ static int ext4_do_update_inode(handle_t *handle,
         struct ext4_inode_info *ei = EXT4_I(inode);
         struct buffer_head *bh = iloc->bh;
         int err = 0, rc, block;
+        uid_t i_uid;
+        gid_t i_gid;
 
         /* For fields not not tracking in the in-memory inode,
          * initialise them to zero for new inodes. */
@@ -3878,27 +3884,27 @@ static int ext4_do_update_inode(handle_t *handle,
 
         ext4_get_inode_flags(ei);
         raw_inode->i_mode = cpu_to_le16(inode->i_mode);
+        i_uid = i_uid_read(inode);
+        i_gid = i_gid_read(inode);
         if (!(test_opt(inode->i_sb, NO_UID32))) {
-                raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid));
-                raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_gid));
+                raw_inode->i_uid_low = cpu_to_le16(low_16_bits(i_uid));
+                raw_inode->i_gid_low = cpu_to_le16(low_16_bits(i_gid));
 /*
  * Fix up interoperability with old kernels. Otherwise, old inodes get
  * re-used with the upper 16 bits of the uid/gid intact
  */
                 if (!ei->i_dtime) {
                         raw_inode->i_uid_high =
-                                cpu_to_le16(high_16_bits(inode->i_uid));
+                                cpu_to_le16(high_16_bits(i_uid));
                         raw_inode->i_gid_high =
-                                cpu_to_le16(high_16_bits(inode->i_gid));
+                                cpu_to_le16(high_16_bits(i_gid));
                 } else {
                         raw_inode->i_uid_high = 0;
                         raw_inode->i_gid_high = 0;
                 }
         } else {
-                raw_inode->i_uid_low =
-                        cpu_to_le16(fs_high2lowuid(inode->i_uid));
-                raw_inode->i_gid_low =
-                        cpu_to_le16(fs_high2lowgid(inode->i_gid));
+                raw_inode->i_uid_low = cpu_to_le16(fs_high2lowuid(i_uid));
+                raw_inode->i_gid_low = cpu_to_le16(fs_high2lowgid(i_gid));
                 raw_inode->i_uid_high = 0;
                 raw_inode->i_gid_high = 0;
         }
@@ -4084,8 +4090,8 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
 
         if (is_quota_modification(inode, attr))
                 dquot_initialize(inode);
-        if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
-                (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {
+        if ((ia_valid & ATTR_UID && !uid_eq(attr->ia_uid, inode->i_uid)) ||
+            (ia_valid & ATTR_GID && !gid_eq(attr->ia_gid, inode->i_gid))) {
                 handle_t *handle;
 
                 /* (user+group)*(old+new) structure, inode write (sb,