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blktrace: fix trace mutex deadlock

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commit 2967acbb257a6a9bf912f4778b727e00972eac9b upstream.

A previous commit changed the locking around registration/cleanup,
but direct callers of blk_trace_remove() were missed. This means
that if we hit the error path in setup, we will deadlock on
attempting to re-acquire the queue trace mutex.

Fixes: 1f2cac107c59 ("blktrace: fix unlocked access to init/start-stop/teardown")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jens Axboe 2017-11-19 11:52:55 -07:00 committed by Greg Kroah-Hartman
parent 4e6958563b
commit cd13258a62
1 changed files with 2 additions and 2 deletions
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4
kernel/trace/blktrace.c
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@ -572,7 +572,7 @@ static int __blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
return ret;
if (copy_to_user(arg, &buts, sizeof(buts))) {
blk_trace_remove(q);
__blk_trace_remove(q);
return -EFAULT;
}
return 0;
@ -618,7 +618,7 @@ static int compat_blk_trace_setup(struct request_queue *q, char *name,
return ret;
if (copy_to_user(arg, &buts.name, ARRAY_SIZE(buts.name))) {
blk_trace_remove(q);
__blk_trace_remove(q);
return -EFAULT;
}