From: Todd Kjos <tkjos@xxxxxxxxxxx>
commit 1909a671dbc3606685b1daf8b22a16f65ea7edda upstream.
syzkallar found a 32-byte memory leak in a rarely executed error
case. The transaction complete work item was not freed if put_user()
failed when writing the BR_TRANSACTION_COMPLETE to the user command
buffer. Fixed by freeing it before put_user() is called.
Reported-by: syzbot+182ce46596c3f2e1eb24@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Todd Kjos <tkjos@xxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/android/binder.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -3936,6 +3936,8 @@ retry:
case BINDER_WORK_TRANSACTION_COMPLETE: {
binder_inner_proc_unlock(proc);
cmd = BR_TRANSACTION_COMPLETE;
+ kfree(w);
+ binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
if (put_user(cmd, (uint32_t __user *)ptr))
return -EFAULT;
ptr += sizeof(uint32_t);
@@ -3944,8 +3946,6 @@ retry:
binder_debug(BINDER_DEBUG_TRANSACTION_COMPLETE,
"%d:%d BR_TRANSACTION_COMPLETE\n",
proc->pid, thread->pid);
- kfree(w);
- binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
} break;
case BINDER_WORK_NODE: {
struct binder_node *node = container_of(w, struct binder_node, work);
