Patch "ANDROID: binder: fix transaction leak." has been added to the 4.14-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    ANDROID: binder: fix transaction leak.

to the 4.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     android-binder-fix-transaction-leak.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From fb2c445277e7b0b4ffe10de8114bad4eccaca948 Mon Sep 17 00:00:00 2001
From: Martijn Coenen <maco@android.com>
Date: Mon, 13 Nov 2017 10:06:08 +0100
Subject: ANDROID: binder: fix transaction leak.

From: Martijn Coenen <maco@android.com>

commit fb2c445277e7b0b4ffe10de8114bad4eccaca948 upstream.

If a call to put_user() fails, we failed to
properly free a transaction and send a failed
reply (if necessary).

Signed-off-by: Martijn Coenen <maco@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/android/binder.c |   40 +++++++++++++++++++++++++++++++---------
 1 file changed, 31 insertions(+), 9 deletions(-)

--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -1948,6 +1948,26 @@ static void binder_send_failed_reply(str
 }
 
 /**
+ * binder_cleanup_transaction() - cleans up undelivered transaction
+ * @t:		transaction that needs to be cleaned up
+ * @reason:	reason the transaction wasn't delivered
+ * @error_code:	error to return to caller (if synchronous call)
+ */
+static void binder_cleanup_transaction(struct binder_transaction *t,
+				       const char *reason,
+				       uint32_t error_code)
+{
+	if (t->buffer->target_node && !(t->flags & TF_ONE_WAY)) {
+		binder_send_failed_reply(t, error_code);
+	} else {
+		binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
+			"undelivered transaction %d, %s\n",
+			t->debug_id, reason);
+		binder_free_transaction(t);
+	}
+}
+
+/**
  * binder_validate_object() - checks for a valid metadata object in a buffer.
  * @buffer:	binder_buffer that we're parsing.
  * @offset:	offset in the buffer at which to validate an object.
@@ -4015,12 +4035,20 @@ retry:
 		if (put_user(cmd, (uint32_t __user *)ptr)) {
 			if (t_from)
 				binder_thread_dec_tmpref(t_from);
+
+			binder_cleanup_transaction(t, "put_user failed",
+						   BR_FAILED_REPLY);
+
 			return -EFAULT;
 		}
 		ptr += sizeof(uint32_t);
 		if (copy_to_user(ptr, &tr, sizeof(tr))) {
 			if (t_from)
 				binder_thread_dec_tmpref(t_from);
+
+			binder_cleanup_transaction(t, "copy_to_user failed",
+						   BR_FAILED_REPLY);
+
 			return -EFAULT;
 		}
 		ptr += sizeof(tr);
@@ -4090,15 +4118,9 @@ static void binder_release_work(struct b
 			struct binder_transaction *t;
 
 			t = container_of(w, struct binder_transaction, work);
-			if (t->buffer->target_node &&
-			    !(t->flags & TF_ONE_WAY)) {
-				binder_send_failed_reply(t, BR_DEAD_REPLY);
-			} else {
-				binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
-					"undelivered transaction %d\n",
-					t->debug_id);
-				binder_free_transaction(t);
-			}
+
+			binder_cleanup_transaction(t, "process died.",
+						   BR_DEAD_REPLY);
 		} break;
 		case BINDER_WORK_RETURN_ERROR: {
 			struct binder_error *e = container_of(


Patches currently in stable-queue which might be from maco@android.com are

queue-4.14/android-binder-fix-transaction-leak.patch