tree 0fbfe042ee8472e8abb5230386370628db6af2a6
parent b4880925650b90cedc82b4044571177165448953
author Jens Axboe <axboe@kernel.dk> 1509898428 -0700
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1589955330 +0200

blktrace: fix unlocked access to init/start-stop/teardown

commit 1f2cac107c591c24b60b115d6050adc213d10fc0 upstream.

sg.c calls into the blktrace functions without holding the proper queue
mutex for doing setup, start/stop, or teardown.

Add internal unlocked variants, and export the ones that do the proper
locking.

Fixes: 6da127ad0918 ("blktrace: Add blktrace ioctls to SCSI generic devices")
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>