2 files changed, 25 insertions, 10 deletions

diff --git a/net/core/scm.c b/net/core/scm.c
index 8f6ccfd68ef4..5472ae7a0657 100644
--- a/net/core/scm.c
+++ b/net/core/scm.c
@@ -45,12 +45,17 @@
 static __inline__ int scm_check_creds(struct ucred *creds)
 {
         const struct cred *cred = current_cred();
+        kuid_t uid = make_kuid(cred->user_ns, creds->uid);
+        kgid_t gid = make_kgid(cred->user_ns, creds->gid);
+
+        if (!uid_valid(uid) || !gid_valid(gid))
+                return -EINVAL;
 
         if ((creds->pid == task_tgid_vnr(current) || capable(CAP_SYS_ADMIN)) &&
-            ((creds->uid == cred->uid   || creds->uid == cred->euid ||
-              creds->uid == cred->suid) || capable(CAP_SETUID)) &&
-            ((creds->gid == cred->gid   || creds->gid == cred->egid ||
-              creds->gid == cred->sgid) || capable(CAP_SETGID))) {
+            ((uid_eq(uid, cred->uid)   || uid_eq(uid, cred->euid) ||
+              uid_eq(uid, cred->suid)) || capable(CAP_SETUID)) &&
+            ((gid_eq(gid, cred->gid)   || gid_eq(gid, cred->egid) ||
+              gid_eq(gid, cred->sgid)) || capable(CAP_SETGID))) {
                return 0;
         }
         return -EPERM;
@@ -149,6 +154,9 @@ int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *p)
                                 goto error;
                         break;
                 case SCM_CREDENTIALS:
+                {
+                        kuid_t uid;
+                        kgid_t gid;
                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct ucred)))
                                 goto error;
                         memcpy(&p->creds, CMSG_DATA(cmsg), sizeof(struct ucred));
@@ -166,22 +174,29 @@ int __scm_send(struct socket *sock, struct msghdr *msg, struct scm_cookie *p)
                                 p->pid = pid;
                         }
 
+                        err = -EINVAL;
+                        uid = make_kuid(current_user_ns(), p->creds.uid);
+                        gid = make_kgid(current_user_ns(), p->creds.gid);
+                        if (!uid_valid(uid) || !gid_valid(gid))
+                                goto error;
+
                         if (!p->cred ||
-                            (p->cred->euid != p->creds.uid) ||
-                            (p->cred->egid != p->creds.gid)) {
+                            !uid_eq(p->cred->euid, uid) ||
+                            !gid_eq(p->cred->egid, gid)) {
                                 struct cred *cred;
                                 err = -ENOMEM;
                                 cred = prepare_creds();
                                 if (!cred)
                                         goto error;
 
-                                cred->uid = cred->euid = p->creds.uid;
-                                cred->gid = cred->egid = p->creds.gid;
+                                cred->uid = cred->euid = uid;
+                                cred->gid = cred->egid = gid;
                                 if (p->cred)
                                         put_cred(p->cred);
                                 p->cred = cred;
                         }
                         break;
+                }
                 default:
                         goto error;
                 }
diff --git a/net/core/sock.c b/net/core/sock.c
index 6b654b3ddfda..9c7fe4ff30fc 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -868,8 +868,8 @@ void cred_to_ucred(struct pid *pid, const struct cred *cred,
         if (cred) {
                 struct user_namespace *current_ns = current_user_ns();
 
-                ucred->uid = from_kuid(current_ns, cred->euid);
-                ucred->gid = from_kgid(current_ns, cred->egid);
+                ucred->uid = from_kuid_munged(current_ns, cred->euid);
+                ucred->gid = from_kgid_munged(current_ns, cred->egid);
         }
 }
 EXPORT_SYMBOL_GPL(cred_to_ucred);