From: Arve Hjønnevåg <arve@android.com>
Date: Mon, 6 Apr 2009 22:12:59 +0000 (-0700)
Subject: Staging: binder: Prevent the wrong thread from adding a transaction to the stack.
X-Git-Tag: v2.6.30-rc3~58^2~23
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=0cf24a7dc9123ddf63c413b6d4b38017b19db713;p=profile%2Fcommon%2Fkernel-common.git

Staging: binder: Prevent the wrong thread from adding a transaction to the stack.

If a thread is part of a transaction stack, it is only allowed to make
another call if it was the target of the top transaction on the stack.

Signed-off-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/staging/android/binder.c b/drivers/staging/android/binder.c
index 91a9629..b0127a3 100644
--- a/drivers/staging/android/binder.c
+++ b/drivers/staging/android/binder.c
@@ -1343,6 +1343,17 @@ binder_transaction(struct binder_proc *proc, struct binder_thread *thread,
 		if (!(tr->flags & TF_ONE_WAY) && thread->transaction_stack) {
 			struct binder_transaction *tmp;
 			tmp = thread->transaction_stack;
+			if (tmp->to_thread != thread) {
+				binder_user_error("binder: %d:%d got new "
+					"transaction with bad transaction stack"
+					", transaction %d has target %d:%d\n",
+					proc->pid, thread->pid, tmp->debug_id,
+					tmp->to_proc ? tmp->to_proc->pid : 0,
+					tmp->to_thread ?
+					tmp->to_thread->pid : 0);
+				return_error = BR_FAILED_REPLY;
+				goto err_bad_call_stack;
+			}
 			while (tmp) {
 				if (tmp->from && tmp->from->proc == target_proc)
 					target_thread = tmp->from;