userns: Convert ptrace, kill, set_priority permission checks to work with kuids and kgids

Update the permission checks to use the new uid_eq and gid_eq helpers
and remove the now unnecessary user_ns equality comparison.

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

1 files changed, 8 insertions, 10 deletions

diff --git a/kernel/sys.c b/kernel/sys.c
index aff09f2..f484077 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -131,9 +131,8 @@ static bool set_one_prio_perm(struct task_struct *p)
 {
 	const struct cred *cred = current_cred(), *pcred = __task_cred(p);
 
-	if (pcred->user_ns == cred->user_ns &&
-	    (pcred->uid  == cred->euid ||
-	     pcred->euid == cred->euid))
+	if (uid_eq(pcred->uid,  cred->euid) ||
+	    uid_eq(pcred->euid, cred->euid))
 		return true;
 	if (ns_capable(pcred->user_ns, CAP_SYS_NICE))
 		return true;
@@ -1582,13 +1581,12 @@ static int check_prlimit_permission(struct task_struct *task)
 		return 0;
 
 	tcred = __task_cred(task);
-	if (cred->user_ns == tcred->user_ns &&
-	    (cred->uid == tcred->euid &&
-	     cred->uid == tcred->suid &&
-	     cred->uid == tcred->uid &&
-	     cred->gid == tcred->egid &&
-	     cred->gid == tcred->sgid &&
-		    cred->gid == tcred->gid))
+	if (uid_eq(cred->uid, tcred->euid) &&
+	    uid_eq(cred->uid, tcred->suid) &&
+	    uid_eq(cred->uid, tcred->uid)  &&
+	    gid_eq(cred->gid, tcred->egid) &&
+	    gid_eq(cred->gid, tcred->sgid) &&
+	    gid_eq(cred->gid, tcred->gid))
 		return 0;
 	if (ns_capable(tcred->user_ns, CAP_SYS_RESOURCE))
 		return 0;