userns: Use cred->user_ns instead of cred->user->user_ns
Optimize performance and prepare for the removal of the user_ns reference
from user_struct. Remove the slow long walk through cred->user->user_ns and
instead go straight to cred->user_ns.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
diff --git a/kernel/sys.c b/kernel/sys.c
index f7a4351..82d8714 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -133,11 +133,11 @@
{
const struct cred *cred = current_cred(), *pcred = __task_cred(p);
- if (pcred->user->user_ns == cred->user->user_ns &&
+ if (pcred->user_ns == cred->user_ns &&
(pcred->uid == cred->euid ||
pcred->euid == cred->euid))
return true;
- if (ns_capable(pcred->user->user_ns, CAP_SYS_NICE))
+ if (ns_capable(pcred->user_ns, CAP_SYS_NICE))
return true;
return false;
}
@@ -1498,7 +1498,7 @@
return 0;
tcred = __task_cred(task);
- if (cred->user->user_ns == tcred->user->user_ns &&
+ if (cred->user_ns == tcred->user_ns &&
(cred->uid == tcred->euid &&
cred->uid == tcred->suid &&
cred->uid == tcred->uid &&
@@ -1506,7 +1506,7 @@
cred->gid == tcred->sgid &&
cred->gid == tcred->gid))
return 0;
- if (ns_capable(tcred->user->user_ns, CAP_SYS_RESOURCE))
+ if (ns_capable(tcred->user_ns, CAP_SYS_RESOURCE))
return 0;
return -EPERM;