binder: fix atomic sleep when get extended error
binder_inner_proc_lock(thread->proc) is a spin lock, copy_to_user can't
be called with in this lock.
Copy it as a local variable to fix it.
Fixes: bd32889e841c ("binder: add BINDER_GET_EXTENDED_ERROR ioctl")
Reported-by: syzbot+46fff6434a7f968ecb39@syzkaller.appspotmail.com
Reviewed-by: Carlos Llamas <cmllamas@google.com>
Signed-off-by: Schspa Shi <schspa@gmail.com>
Link: https://lore.kernel.org/r/20220518011754.49348-1-schspa@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: I1de3962ef9b29208c97df6379d5bc46942accef1
diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 270182c..7295660 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -5157,19 +5157,16 @@
static int binder_ioctl_get_extended_error(struct binder_thread *thread,
void __user *ubuf)
{
- struct binder_extended_error *ee = &thread->ee;
+ struct binder_extended_error ee;
binder_inner_proc_lock(thread->proc);
- if (copy_to_user(ubuf, ee, sizeof(*ee))) {
- binder_inner_proc_unlock(thread->proc);
- return -EFAULT;
- }
-
- ee->id = 0;
- ee->command = BR_OK;
- ee->param = 0;
+ ee = thread->ee;
+ binder_set_extended_error(&thread->ee, 0, BR_OK, 0);
binder_inner_proc_unlock(thread->proc);
+ if (copy_to_user(ubuf, &ee, sizeof(ee)))
+ return -EFAULT;
+
return 0;
}