1 files changed, 34 insertions, 23 deletions

diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index 217a0bef3c8..4d9825f9962 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -67,7 +67,8 @@ struct key root_session_keyring = {
 /*
  * allocate the keyrings to be associated with a UID
  */
-int alloc_uid_keyring(struct user_struct *user)
+int alloc_uid_keyring(struct user_struct *user,
+		      struct task_struct *ctx)
 {
 	struct key *uid_keyring, *session_keyring;
 	char buf[20];
@@ -76,7 +77,7 @@ int alloc_uid_keyring(struct user_struct *user)
 	/* concoct a default session keyring */
 	sprintf(buf, "_uid_ses.%u", user->uid);
 
-	session_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, 0, NULL);
+	session_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, ctx, 0, NULL);
 	if (IS_ERR(session_keyring)) {
 		ret = PTR_ERR(session_keyring);
 		goto error;
@@ -86,7 +87,7 @@ int alloc_uid_keyring(struct user_struct *user)
 	 * keyring */
 	sprintf(buf, "_uid.%u", user->uid);
 
-	uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, 0,
+	uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1, ctx, 0,
 				    session_keyring);
 	if (IS_ERR(uid_keyring)) {
 		key_put(session_keyring);
@@ -143,7 +144,7 @@ int install_thread_keyring(struct task_struct *tsk)
 
 	sprintf(buf, "_tid.%u", tsk->pid);
 
-	keyring = keyring_alloc(buf, tsk->uid, tsk->gid, 1, NULL);
+	keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, 1, NULL);
 	if (IS_ERR(keyring)) {
 		ret = PTR_ERR(keyring);
 		goto error;
@@ -177,7 +178,7 @@ int install_process_keyring(struct task_struct *tsk)
 	if (!tsk->signal->process_keyring) {
 		sprintf(buf, "_pid.%u", tsk->tgid);
 
-		keyring = keyring_alloc(buf, tsk->uid, tsk->gid, 1, NULL);
+		keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, 1, NULL);
 		if (IS_ERR(keyring)) {
 			ret = PTR_ERR(keyring);
 			goto error;
@@ -217,7 +218,7 @@ static int install_session_keyring(struct task_struct *tsk,
 	if (!keyring) {
 		sprintf(buf, "_ses.%u", tsk->tgid);
 
-		keyring = keyring_alloc(buf, tsk->uid, tsk->gid, 1, NULL);
+		keyring = keyring_alloc(buf, tsk->uid, tsk->gid, tsk, 1, NULL);
 		if (IS_ERR(keyring))
 			return PTR_ERR(keyring);
 	}
@@ -390,6 +391,8 @@ key_ref_t search_process_keyrings(struct key_type *type,
 	struct request_key_auth *rka;
 	key_ref_t key_ref, ret, err;
 
+	might_sleep();
+
 	/* we want to return -EAGAIN or -ENOKEY if any of the keyrings were
 	 * searchable, but we failed to find a key or we found a negative key;
 	 * otherwise we want to return a sample error (probably -EACCES) if
@@ -495,27 +498,35 @@ key_ref_t search_process_keyrings(struct key_type *type,
 	 */
 	if (context->request_key_auth &&
 	    context == current &&
-	    type != &key_type_request_key_auth &&
-	    key_validate(context->request_key_auth) == 0
+	    type != &key_type_request_key_auth
 	    ) {
-		rka = context->request_key_auth->payload.data;
+		/* defend against the auth key being revoked */
+		down_read(&context->request_key_auth->sem);
 
-		key_ref = search_process_keyrings(type, description, match,
-						  rka->context);
+		if (key_validate(context->request_key_auth) == 0) {
+			rka = context->request_key_auth->payload.data;
 
-		if (!IS_ERR(key_ref))
-			goto found;
+			key_ref = search_process_keyrings(type, description,
+							  match, rka->context);
 
-		switch (PTR_ERR(key_ref)) {
-		case -EAGAIN: /* no key */
-			if (ret)
+			up_read(&context->request_key_auth->sem);
+
+			if (!IS_ERR(key_ref))
+				goto found;
+
+			switch (PTR_ERR(key_ref)) {
+			case -EAGAIN: /* no key */
+				if (ret)
+					break;
+			case -ENOKEY: /* negative key */
+				ret = key_ref;
 				break;
-		case -ENOKEY: /* negative key */
-			ret = key_ref;
-			break;
-		default:
-			err = key_ref;
-			break;
+			default:
+				err = key_ref;
+				break;
+			}
+		} else {
+			up_read(&context->request_key_auth->sem);
 		}
 	}
 
@@ -717,7 +728,7 @@ long join_session_keyring(const char *name)
 	keyring = find_keyring_by_name(name, 0);
 	if (PTR_ERR(keyring) == -ENOKEY) {
 		/* not found - try and create a new one */
-		keyring = keyring_alloc(name, tsk->uid, tsk->gid, 0, NULL);
+		keyring = keyring_alloc(name, tsk->uid, tsk->gid, tsk, 0, NULL);
 		if (IS_ERR(keyring)) {
 			ret = PTR_ERR(keyring);
 			goto error2;