4 files changed, 34 insertions, 16 deletions

diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index d54f73c558f7..19be69fa4d05 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -980,14 +980,19 @@ long keyctl_chown_key(key_serial_t id, uid_t user, gid_t group)
 	ret = -EACCES;
 	down_write(&key->sem);
 
-	if (!capable(CAP_SYS_ADMIN)) {
+	{
+		bool is_privileged_op = false;
+
 		/* only the sysadmin can chown a key to some other UID */
 		if (user != (uid_t) -1 && !uid_eq(key->uid, uid))
-			goto error_put;
+			is_privileged_op = true;
 
 		/* only the sysadmin can set the key's GID to a group other
 		 * than one of those that the current process subscribes to */
 		if (group != (gid_t) -1 && !gid_eq(gid, key->gid) && !in_group_p(gid))
+			is_privileged_op = true;
+
+		if (is_privileged_op && !capable(CAP_SYS_ADMIN))
 			goto error_put;
 	}
 
@@ -1088,7 +1093,7 @@ long keyctl_setperm_key(key_serial_t id, key_perm_t perm)
 	down_write(&key->sem);
 
 	/* if we're not the sysadmin, we can only change a key that we own */
-	if (capable(CAP_SYS_ADMIN) || uid_eq(key->uid, current_fsuid())) {
+	if (uid_eq(key->uid, current_fsuid()) || capable(CAP_SYS_ADMIN)) {
 		key->perm = perm;
 		notify_key(key, NOTIFY_KEY_SETATTR, 0);
 		ret = 0;
diff --git a/security/keys/request_key.c b/security/keys/request_key.c
index 07a0ef2baacd..a7673ad86d18 100644
--- a/security/keys/request_key.c
+++ b/security/keys/request_key.c
@@ -401,17 +401,21 @@ static int construct_alloc_key(struct keyring_search_context *ctx,
 	set_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags);
 
 	if (dest_keyring) {
-		ret = __key_link_lock(dest_keyring, &ctx->index_key);
+		ret = __key_link_lock(dest_keyring, &key->index_key);
 		if (ret < 0)
 			goto link_lock_failed;
-		ret = __key_link_begin(dest_keyring, &ctx->index_key, &edit);
-		if (ret < 0)
-			goto link_prealloc_failed;
 	}
 
-	/* attach the key to the destination keyring under lock, but we do need
+	/*
+	 * Attach the key to the destination keyring under lock, but we do need
 	 * to do another check just in case someone beat us to it whilst we
-	 * waited for locks */
+	 * waited for locks.
+	 *
+	 * The caller might specify a comparison function which looks for keys
+	 * that do not exactly match but are still equivalent from the caller's
+	 * perspective. The __key_link_begin() operation must be done only after
+	 * an actual key is determined.
+	 */
 	mutex_lock(&key_construction_mutex);
 
 	rcu_read_lock();
@@ -420,12 +424,16 @@ static int construct_alloc_key(struct keyring_search_context *ctx,
 	if (!IS_ERR(key_ref))
 		goto key_already_present;
 
-	if (dest_keyring)
+	if (dest_keyring) {
+		ret = __key_link_begin(dest_keyring, &key->index_key, &edit);
+		if (ret < 0)
+			goto link_alloc_failed;
 		__key_link(dest_keyring, key, &edit);
+	}
 
 	mutex_unlock(&key_construction_mutex);
 	if (dest_keyring)
-		__key_link_end(dest_keyring, &ctx->index_key, edit);
+		__key_link_end(dest_keyring, &key->index_key, edit);
 	mutex_unlock(&user->cons_lock);
 	*_key = key;
 	kleave(" = 0 [%d]", key_serial(key));
@@ -438,10 +446,13 @@ key_already_present:
 	mutex_unlock(&key_construction_mutex);
 	key = key_ref_to_ptr(key_ref);
 	if (dest_keyring) {
+		ret = __key_link_begin(dest_keyring, &key->index_key, &edit);
+		if (ret < 0)
+			goto link_alloc_failed_unlocked;
 		ret = __key_link_check_live_key(dest_keyring, key);
 		if (ret == 0)
 			__key_link(dest_keyring, key, &edit);
-		__key_link_end(dest_keyring, &ctx->index_key, edit);
+		__key_link_end(dest_keyring, &key->index_key, edit);
 		if (ret < 0)
 			goto link_check_failed;
 	}
@@ -456,8 +467,10 @@ link_check_failed:
 	kleave(" = %d [linkcheck]", ret);
 	return ret;
 
-link_prealloc_failed:
-	__key_link_end(dest_keyring, &ctx->index_key, edit);
+link_alloc_failed:
+	mutex_unlock(&key_construction_mutex);
+link_alloc_failed_unlocked:
+	__key_link_end(dest_keyring, &key->index_key, edit);
 link_lock_failed:
 	mutex_unlock(&user->cons_lock);
 	key_put(key);
diff --git a/security/keys/sysctl.c b/security/keys/sysctl.c
index b72b82bb20c6..b348e1679d5d 100644
--- a/security/keys/sysctl.c
+++ b/security/keys/sysctl.c
@@ -9,7 +9,7 @@
 #include <linux/sysctl.h>
 #include "internal.h"
 
-struct ctl_table key_sysctls[] = {
+static struct ctl_table key_sysctls[] = {
 	{
 		.procname = "maxkeys",
 		.data = &key_quota_maxkeys,
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index 2b2c8eb258d5..bc700f85f80b 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -186,7 +186,7 @@ int tpm2_key_priv(void *context, size_t hdrlen,
 }
 
 /**
- * tpm_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer.
+ * tpm2_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer.
  *
  * @buf: an allocated tpm_buf instance
  * @session_handle: session handle