crypto: caam/qi - Fix drv_ctx refcount bug

commit b7b39df7e710b0068356e4c696af07aa10e2cd3d upstream.

Ensure refcount is raised before request is enqueued since it could
be dequeued before the call returns.

Reported-by: Sean Anderson <[email protected]>
Cc: <[email protected]>
Fixes: 1114441 ("crypto: caam/qi - optimize frame queue cleanup")
Signed-off-by: Herbert Xu <[email protected]>
Reviewed-by: Horia Geantă <[email protected]>
Tested-by: Sean Anderson <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
(cherry picked from commit 877ee3ba2f78c3cdb3eddd6517e8f9807ea9ceb3)
Signed-off-by: Vijayendra Suman <[email protected]>

Author: herbertx

drivers/crypto/caam/qi.c

@@ -115,12 +115,12 @@ int caam_qi_enqueue(struct device *qidev, struct caam_drv_req *req)
 	qm_fd_addr_set64(&fd, addr);
 
 	do {
+		refcount_inc(&req->drv_ctx->refcnt);
 		ret = qman_enqueue(req->drv_ctx->req_fq, &fd);
-		if (likely(!ret)) {
-			refcount_inc(&req->drv_ctx->refcnt);
+		if (likely(!ret))
 			return 0;
-		}
 
+		refcount_dec(&req->drv_ctx->refcnt);
 		if (ret != -EBUSY)
 			break;
 		num_retries++;