From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Biggers , David Howells , James Morris , Sasha Levin Subject: [PATCH 4.4 019/114] KEYS: put keyring if install_session_keyring_to_cred() fails Date: Thu, 8 Nov 2018 13:50:34 -0800 Message-Id: <20181108215100.897428351@linuxfoundation.org> In-Reply-To: <20181108215059.051093652@linuxfoundation.org> References: <20181108215059.051093652@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit d636bd9f12a66ea3775c9fabbf3f8e118253467a ] In join_session_keyring(), if install_session_keyring_to_cred() were to fail, we would leak the keyring reference, just like in the bug fixed by commit 23567fd052a9 ("KEYS: Fix keyring ref leak in join_session_keyring()"). Fortunately this cannot happen currently, but we really should be more careful. Do this by adding and using a new error label at which the keyring reference is dropped. Signed-off-by: Eric Biggers Signed-off-by: David Howells Signed-off-by: James Morris Signed-off-by: Sasha Levin --- security/keys/process_keys.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c index ac1d5b2b1626..a7095372701e 100644 --- a/security/keys/process_keys.c +++ b/security/keys/process_keys.c @@ -808,15 +808,14 @@ long join_session_keyring(const char *name) ret = PTR_ERR(keyring); goto error2; } else if (keyring == new->session_keyring) { - key_put(keyring); ret = 0; - goto error2; + goto error3; } /* we've got a keyring - now to install it */ ret = install_session_keyring_to_cred(new, keyring); if (ret < 0) - goto error2; + goto error3; commit_creds(new); mutex_unlock(&key_session_mutex); @@ -826,6 +825,8 @@ long join_session_keyring(const char *name) okay: return ret; +error3: + key_put(keyring); error2: mutex_unlock(&key_session_mutex); error: -- 2.17.1