[PATCH 2/2] binder: fix is_failure flag for superseded transaction cleanup

[Tomer Pomeranc]

When a TF_UPDATE_TXN transaction supersedes a pending async transaction,
binder_release_entire_buffer() is called with is_failure=false. Since the
superseded transaction was never delivered, binder_apply_fd_fixups() was
never called and no fds were installed in the target process.

With is_failure=false, the BINDER_TYPE_FDA cleanup handler interprets
stale buffer contents as installed fd numbers and passes them to
binder_deferred_fd_close(), closing unrelated file descriptors.

Pass is_failure=true since the transaction was never delivered to the
target, matching the semantics of all other undelivered-transaction
cleanup paths.

Fixes: 9864bb480133 ("binder: add TF_UPDATE_TXN to replace outdated txn")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Tomer Pomeranc <tomerpo@xxxxxxxxx>
---
 drivers/android/binder.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index f70aeb63a..bc8bc9ee4 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -2930,7 +2930,7 @@ static int binder_proc_transaction(struct binder_transaction *t,
 		t_outdated->buffer = NULL;
 		buffer->transaction = NULL;
 		trace_binder_transaction_update_buffer_release(buffer);
-		binder_release_entire_buffer(proc, NULL, buffer, false);
+		binder_release_entire_buffer(proc, NULL, buffer, true);
 		binder_alloc_free_buf(&proc->alloc, buffer);
 		binder_free_txn_fixups(t_outdated);
 		kfree(t_outdated);
-- 
2.34.1