mirror of
https://github.com/torvalds/linux.git
synced 2026-09-25 21:21:09 -04:00
Johannes Berg
6736fde967
The code within wait_event_interruptible() is called with
!TASK_RUNNING, so mustn't call any functions that can sleep,
like mutex_lock().
Since we re-check the list_empty() in a loop after the wait,
it's safe to simply use list_empty() without locking.
This bug has existed forever, but was only discovered now
because all userspace implementations, including the default
'rfkill' tool, use poll() or select() to get a readable fd
before attempting to read.
Cc: [email protected]
Fixes: c64fb01627 ("rfkill: create useful userspace interface")
Reported-by: Dmitry Vyukov <[email protected]>
Signed-off-by: Johannes Berg <[email protected]>