userns: Convert hugetlbfs to use kuid/kgid where appropriate

Note sysctl_hugetlb_shm_group can only be written in the root user
in the initial user namespace, so we can assume sysctl_hugetlb_shm_group
is in the initial user namespace.

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

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 8349a89..6e572c4 100644 (file)
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -42,8 +42,8 @@ static const struct inode_operations hugetlbfs_dir_inode_operations;
 static const struct inode_operations hugetlbfs_inode_operations;
 
 struct hugetlbfs_config {
-       uid_t   uid;
-       gid_t   gid;
+       kuid_t   uid;
+       kgid_t   gid;
        umode_t mode;
        long    nr_blocks;
        long    nr_inodes;
@@ -785,13 +785,17 @@ hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig)
                case Opt_uid:
                        if (match_int(&args[0], &option))
                                goto bad_val;
-                       pconfig->uid = option;
+                       pconfig->uid = make_kuid(current_user_ns(), option);
+                       if (!uid_valid(pconfig->uid))
+                               goto bad_val;
                        break;
 
                case Opt_gid:
                        if (match_int(&args[0], &option))
                                goto bad_val;
-                       pconfig->gid = option;
+                       pconfig->gid = make_kgid(current_user_ns(), option);
+                       if (!gid_valid(pconfig->gid))
+                               goto bad_val;
                        break;
 
                case Opt_mode:
@@ -924,7 +928,9 @@ static struct vfsmount *hugetlbfs_vfsmount;
 
 static int can_do_hugetlb_shm(void)
 {
-       return capable(CAP_IPC_LOCK) || in_group_p(sysctl_hugetlb_shm_group);
+       kgid_t shm_group;
+       shm_group = make_kgid(&init_user_ns, sysctl_hugetlb_shm_group);
+       return capable(CAP_IPC_LOCK) || in_group_p(shm_group);
 }
 
 struct file *hugetlb_file_setup(const char *name, unsigned long addr,

diff --git a/init/Kconfig b/init/Kconfig
index 96007af..7ee6e19 100644 (file)
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -954,7 +954,6 @@ config UIDGID_CONVERTED
        depends on HFS_FS = n
        depends on HFSPLUS_FS = n
        depends on HPFS_FS = n
-       depends on HUGETLBFS = n
        depends on ISO9660_FS = n
        depends on JFFS2_FS = n
        depends on JFS_FS = n