1 files changed, 24 insertions, 23 deletions

diff --git a/kernel/sys.c b/kernel/sys.c
index e7dc0e10a485..37f458e6882a 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -559,7 +559,7 @@ error:
         abort_creds(new);
         return retval;
 }
-  
+
 /*
  * change the user struct in a credentials set to match the new UID
  */
@@ -571,6 +571,11 @@ static int set_user(struct cred *new)
         if (!new_user)
                 return -EAGAIN;
 
+        if (!task_can_switch_user(new_user, current)) {
+                free_uid(new_user);
+                return -EINVAL;
+        }
+
         if (atomic_read(&new_user->processes) >=
                                 current->signal->rlim[RLIMIT_NPROC].rlim_cur &&
                         new_user != INIT_USER) {
@@ -631,10 +636,11 @@ SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid)
                         goto error;
         }
 
-        retval = -EAGAIN;
-        if (new->uid != old->uid && set_user(new) < 0)
-                goto error;
-
+        if (new->uid != old->uid) {
+                retval = set_user(new);
+                if (retval < 0)
+                        goto error;
+        }
         if (ruid != (uid_t) -1 ||
             (euid != (uid_t) -1 && euid != old->uid))
                 new->suid = new->euid;
@@ -680,9 +686,10 @@ SYSCALL_DEFINE1(setuid, uid_t, uid)
         retval = -EPERM;
         if (capable(CAP_SETUID)) {
                 new->suid = new->uid = uid;
-                if (uid != old->uid && set_user(new) < 0) {
-                        retval = -EAGAIN;
-                        goto error;
+                if (uid != old->uid) {
+                        retval = set_user(new);
+                        if (retval < 0)
+                                goto error;
                 }
         } else if (uid != old->uid && uid != new->suid) {
                 goto error;
@@ -734,11 +741,13 @@ SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid)
                         goto error;
         }
 
-        retval = -EAGAIN;
         if (ruid != (uid_t) -1) {
                 new->uid = ruid;
-                if (ruid != old->uid && set_user(new) < 0)
-                        goto error;
+                if (ruid != old->uid) {
+                        retval = set_user(new);
+                        if (retval < 0)
+                                goto error;
+                }
         }
         if (euid != (uid_t) -1)
                 new->euid = euid;
@@ -1525,22 +1534,14 @@ SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim)
                 return -EINVAL;
         if (copy_from_user(&new_rlim, rlim, sizeof(*rlim)))
                 return -EFAULT;
+        if (new_rlim.rlim_cur > new_rlim.rlim_max)
+                return -EINVAL;
         old_rlim = current->signal->rlim + resource;
         if ((new_rlim.rlim_max > old_rlim->rlim_max) &&
             !capable(CAP_SYS_RESOURCE))
                 return -EPERM;
-
-        if (resource == RLIMIT_NOFILE) {
-                if (new_rlim.rlim_max == RLIM_INFINITY)
-                        new_rlim.rlim_max = sysctl_nr_open;
-                if (new_rlim.rlim_cur == RLIM_INFINITY)
-                        new_rlim.rlim_cur = sysctl_nr_open;
-                if (new_rlim.rlim_max > sysctl_nr_open)
-                        return -EPERM;
-        }
-
-        if (new_rlim.rlim_cur > new_rlim.rlim_max)
-                return -EINVAL;
+        if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > sysctl_nr_open)
+                return -EPERM;
 
         retval = security_task_setrlimit(resource, &new_rlim);
         if (retval)