[PATCH] binder: fix offset calculation in debug log

[Carlos Llamas]

The vma start address should be substracted from the buffer's user data
address and not the other way around.

Cc: Tiffany Y. Yang <ynaffit@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 162c79731448 ("binder: avoid user addresses in debug logs")
Signed-off-by: Carlos Llamas <cmllamas@xxxxxxxxxx>
---
 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 76052006bd87..5fc2c8ee61b1 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -6373,7 +6373,7 @@ static void print_binder_transaction_ilocked(struct seq_file *m,
 		seq_printf(m, " node %d", buffer->target_node->debug_id);
 	seq_printf(m, " size %zd:%zd offset %lx\n",
 		   buffer->data_size, buffer->offsets_size,
-		   proc->alloc.vm_start - buffer->user_data);
+		   buffer->user_data - proc->alloc.vm_start);
 }
 
 static void print_binder_work_ilocked(struct seq_file *m,
-- 
2.49.0.395.g12beb8f557-goog