X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=kernel%2Fuser.c;h=220e586127a0ca9cd65b3ccfd6b01c4620fef2e7;hb=bd3c97a7c718bfb9f1e4f31c16c383a5c6f815eb;hp=d9deae43a9abbb0f8dfaeeb078e8fb83311bc481;hpb=fab8d6ddf6dee2608869005d45fe97f70e4f5bdd;p=powerpc.git

diff --git a/kernel/user.c b/kernel/user.c
index d9deae43a9..220e586127 100644
--- a/kernel/user.c
+++ b/kernel/user.c
@@ -105,15 +105,19 @@ void free_uid(struct user_struct *up)
 {
 	unsigned long flags;
 
+	if (!up)
+		return;
+
 	local_irq_save(flags);
-	if (up && atomic_dec_and_lock(&up->__count, &uidhash_lock)) {
+	if (atomic_dec_and_lock(&up->__count, &uidhash_lock)) {
 		uid_hash_remove(up);
+		spin_unlock_irqrestore(&uidhash_lock, flags);
 		key_put(up->uid_keyring);
 		key_put(up->session_keyring);
 		kmem_cache_free(uid_cachep, up);
-		spin_unlock(&uidhash_lock);
+	} else {
+		local_irq_restore(flags);
 	}
-	local_irq_restore(flags);
 }
 
 struct user_struct * alloc_uid(uid_t uid)
@@ -136,7 +140,7 @@ struct user_struct * alloc_uid(uid_t uid)
 		atomic_set(&new->processes, 0);
 		atomic_set(&new->files, 0);
 		atomic_set(&new->sigpending, 0);
-#ifdef CONFIG_INOTIFY
+#ifdef CONFIG_INOTIFY_USER
 		atomic_set(&new->inotify_watches, 0);
 		atomic_set(&new->inotify_devs, 0);
 #endif
@@ -144,7 +148,7 @@ struct user_struct * alloc_uid(uid_t uid)
 		new->mq_bytes = 0;
 		new->locked_shm = 0;
 
-		if (alloc_uid_keyring(new) < 0) {
+		if (alloc_uid_keyring(new, current) < 0) {
 			kmem_cache_free(uid_cachep, new);
 			return NULL;
 		}
@@ -183,6 +187,17 @@ void switch_uid(struct user_struct *new_user)
 	atomic_dec(&old_user->processes);
 	switch_uid_keyring(new_user);
 	current->user = new_user;
+
+	/*
+	 * We need to synchronize with __sigqueue_alloc()
+	 * doing a get_uid(p->user).. If that saw the old
+	 * user value, we need to wait until it has exited
+	 * its critical region before we can free the old
+	 * structure.
+	 */
+	smp_mb();
+	spin_unlock_wait(&current->sighand->siglock);
+
 	free_uid(old_user);
 	suid_keys(current);
 }