io_uring/tctx: check for setup tctx->io_wq before teardown

As with the idling code before it, the error exit path should check for
a NULL tctx->io_wq before calling io_wq_put_and_exit().

Fixes: 7880174 ("io_uring/tctx: clean up __io_uring_add_tctx_node() error handling")
Reported-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Clément Léger <cleger@meta.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Author: axboe

io_uring/tctx.c

@@ -171,7 +171,8 @@ int __io_uring_add_tctx_node(struct io_ring_ctx *ctx)
 	}
 	if (!current->io_uring) {
 err_free:
-		io_wq_put_and_exit(tctx->io_wq);
+		if (tctx->io_wq)
+			io_wq_put_and_exit(tctx->io_wq);
 		percpu_counter_destroy(&tctx->inflight);
 		kfree(tctx);
 	}