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, syzbot+09e05aba06723a94d43d@syzkaller.appspotmail.com, Martijn Coenen Subject: [PATCH 4.14 59/91] ANDROID: binder: prevent transactions into own process. Date: Mon, 30 Apr 2018 12:24:41 -0700 Message-Id: <20180430184007.246412352@linuxfoundation.org> In-Reply-To: <20180430184004.216234025@linuxfoundation.org> References: <20180430184004.216234025@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Martijn Coenen commit 7aa135fcf26377f92dc0680a57566b4c7f3e281b upstream. This can't happen with normal nodes (because you can't get a ref to a node you own), but it could happen with the context manager; to make the behavior consistent with regular nodes, reject transactions into the context manager by the process owning it. Reported-by: syzbot+09e05aba06723a94d43d@syzkaller.appspotmail.com Signed-off-by: Martijn Coenen Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/android/binder.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -2785,6 +2785,14 @@ static void binder_transaction(struct bi else return_error = BR_DEAD_REPLY; mutex_unlock(&context->context_mgr_node_lock); + if (target_node && target_proc == proc) { + binder_user_error("%d:%d got transaction to context manager from process owning it\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_invalid_target_handle; + } } if (!target_node) { /*