[PATCH 34/43] userns: Convert devpts to use kuid/kgid where appropriate

"Eric W. Beiderman
2012-04-08T05:17:44Z

From: Eric W. Biederman <ebiederm@xmission.com>

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
---
fs/devpts/inode.c | 24 ++++++++++++++++--------
1 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c
index 10f5e0b..979c1e3 100644
--- a/fs/devpts/inode.c
+++ b/fs/devpts/inode.c
@@ -98,8 +98,8 @@ static struct vfsmount *devpts_mnt;
struct pts_mount_opts {
int setuid;
int setgid;
- uid_t uid;
- gid_t gid;
+ kuid_t uid;
+ kgid_t gid;
umode_t mode;
umode_t ptmxmode;
int newinstance;
@@ -158,11 +158,13 @@ static inline struct super_block *pts_sb_from_inode(struct inode *inode)
static int parse_mount_options(char *data, int op, struct pts_mount_opts *opts)
{
char *p;
+ kuid_t uid;
+ kgid_t gid;

opts->setuid = 0;
opts->setgid = 0;
- opts->uid = 0;
- opts->gid = 0;
+ opts->uid = GLOBAL_ROOT_UID;
+ opts->gid = GLOBAL_ROOT_GID;
opts->mode = DEVPTS_DEFAULT_MODE;
opts->ptmxmode = DEVPTS_DEFAULT_PTMX_MODE;
opts->max = NR_UNIX98_PTY_MAX;
@@ -184,13 +186,19 @@ static int parse_mount_options(char *data, int op, struct pts_mount_opts *opts)
case Opt_uid:
if (match_int(&args[0], &option))
return -EINVAL;
- opts->uid = option;
+ uid = make_kuid(current_user_ns(), option);
+ if (!uid_valid(uid))
+ return -EINVAL;
+ opts->uid = uid;
opts->setuid = 1;
break;
case Opt_gid:
if (match_int(&args[0], &option))
return -EINVAL;
- opts->gid = option;
+ gid = make_kgid(current_user_ns(), option);
+ if (!gid_valid(gid))
+ return -EINVAL;
+ opts->gid = gid;
opts->setgid = 1;
break;
case Opt_mode:
@@ -315,9 +323,9 @@ static int devpts_show_options(struct seq_file *seq, struct dentry *root)
struct pts_mount_opts *opts = &fsi->mount_opts;

if (opts->setuid)
- seq_printf(seq, ",uid=%u", opts->uid);
+ seq_printf(seq, ",uid=%u", from_kuid_munged(&init_user_ns, opts->uid));
if (opts->setgid)
- seq_printf(seq, ",gid=%u", opts->gid);
+ seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, opts->gid));
seq_printf(seq, ",mode=%03o", opts->mode);
#ifdef CONFIG_DEVPTS_MULTIPLE_INSTANCES
seq_printf(seq, ",ptmxmode=%03o", opts->ptmxmode);
--
1.7.2.5