FAILED: patch "[PATCH] test_firmware: fix a memory leak with reqs buffer" failed to apply to 5.15-stable tree

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x be37bed754ed90b2655382f93f9724b3c1aae847
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2023060711-daybed-acting-a047@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From be37bed754ed90b2655382f93f9724b3c1aae847 Mon Sep 17 00:00:00 2001
From: Mirsad Goran Todorovac <[email protected]>
Date: Tue, 9 May 2023 10:47:47 +0200
Subject: [PATCH] test_firmware: fix a memory leak with reqs buffer

Dan Carpenter spotted that test_fw_config->reqs will be leaked if trigger_batched_requests_store() is called two or more times. The same appears with trigger_batched_requests_async_store().

This bug wasn't trigger by the tests, but observed by Dan's visual inspection of the code.

The recommended workaround was to return -EBUSY if test_fw_config->reqs is already allocated.

index 35417e0af3f4..91b232ed3161 100644
@@ -913,6 +913,11 @@ static ssize_t trigger_batched_requests_store(struct device *dev,
 
 	mutex_lock(&test_fw_mutex);
 
+	if (test_fw_config->reqs) {
+		rc = -EBUSY;
+		goto out_bail;
+	}
+
 	test_fw_config->reqs =
 		vzalloc(array3_size(sizeof(struct test_batched_req),
 				    test_fw_config->num_requests, 2));

@@ -1011,6 +1016,11 @@ ssize_t trigger_batched_requests_async_store(struct device *dev,
 
 	mutex_lock(&test_fw_mutex);
 
+	if (test_fw_config->reqs) {
+		rc = -EBUSY;
+		goto out_bail;
+	}
+
 	test_fw_config->reqs =
 		vzalloc(array3_size(sizeof(struct test_batched_req),
 				    test_fw_config->num_requests, 2));