| From 7aa135fcf26377f92dc0680a57566b4c7f3e281b Mon Sep 17 00:00:00 2001 |
| From: Martijn Coenen <maco@android.com> |
| Date: Wed, 28 Mar 2018 11:14:50 +0200 |
| Subject: ANDROID: binder: prevent transactions into own process. |
| |
| From: Martijn Coenen <maco@android.com> |
| |
| 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 <maco@android.com> |
| Cc: stable <stable@vger.kernel.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/android/binder.c | 8 ++++++++ |
| 1 file changed, 8 insertions(+) |
| |
| --- a/drivers/android/binder.c |
| +++ b/drivers/android/binder.c |
| @@ -2839,6 +2839,14 @@ 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) { |
| /* |
