userns: Convert group_info values from gid_t to kgid_t.
As a first step to converting struct cred to be all kuid_t and kgid_t
values convert the group values stored in group_info to always be
kgid_t values. Unless user namespaces are used this change should
have no effect.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
diff --git a/arch/s390/kernel/compat_linux.c b/arch/s390/kernel/compat_linux.c
index ab64bdb..f0273ed 100644
--- a/arch/s390/kernel/compat_linux.c
+++ b/arch/s390/kernel/compat_linux.c
@@ -173,11 +173,14 @@
static int groups16_to_user(u16 __user *grouplist, struct group_info *group_info)
{
+ struct user_namespace *user_ns = current_user_ns();
int i;
u16 group;
+ kgid_t kgid;
for (i = 0; i < group_info->ngroups; i++) {
- group = (u16)GROUP_AT(group_info, i);
+ kgid = GROUP_AT(group_info, i);
+ group = (u16)from_kgid_munged(user_ns, kgid);
if (put_user(group, grouplist+i))
return -EFAULT;
}
@@ -187,13 +190,20 @@
static int groups16_from_user(struct group_info *group_info, u16 __user *grouplist)
{
+ struct user_namespace *user_ns = current_user_ns();
int i;
u16 group;
+ kgid_t kgid;
for (i = 0; i < group_info->ngroups; i++) {
if (get_user(group, grouplist+i))
return -EFAULT;
- GROUP_AT(group_info, i) = (gid_t)group;
+
+ kgid = make_kgid(user_ns, (gid_t)group);
+ if (!gid_valid(kgid))
+ return -EINVAL;
+
+ GROUP_AT(group_info, i) = kgid;
}
return 0;