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/signal.c b/kernel/signal.c
index 17afcaf..e2c5d84 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -767,14 +767,14 @@
const struct cred *cred = current_cred();
const struct cred *tcred = __task_cred(t);
- if (cred->user->user_ns == tcred->user->user_ns &&
+ if (cred->user_ns == tcred->user_ns &&
(cred->euid == tcred->suid ||
cred->euid == tcred->uid ||
cred->uid == tcred->suid ||
cred->uid == tcred->uid))
return 1;
- if (ns_capable(tcred->user->user_ns, CAP_KILL))
+ if (ns_capable(tcred->user_ns, CAP_KILL))
return 1;
return 0;