[PATCH 4.19 19/49] Revert "rapidio: fix a NULL pointer dereference when create_workqueue() fails"

Greg Kroah-Hartman
2021-05-24T15:49:08Z

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 5e68b86c7b7c059c0f0ec4bf8adabe63f84a61eb upstream.

This reverts commit 23015b22e47c5409620b1726a677d69e5cd032ba.

Because of recent interactions with developers from @umn.edu, all
commits from them have been recently re-reviewed to ensure if they were
correct or not.

Upon review, this commit was found to be incorrect for the reasons
below, so it must be reverted. It will be fixed up "correctly" in a
later kernel change.

The original commit has a memory leak on the error path here, it does
not clean up everything properly.

Cc: Kangjie Lu <kjlu@umn.edu>
Cc: Alexandre Bounine <alex.bou9@gmail.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Fixes: 23015b22e47c ("rapidio: fix a NULL pointer dereference when create_workqueue() fails")
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210503115736.2104747-45-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/rapidio/rio_cm.c | 8 --------
1 file changed, 8 deletions(-)

--- a/drivers/rapidio/rio_cm.c
+++ b/drivers/rapidio/rio_cm.c
@@ -2147,14 +2147,6 @@ static int riocm_add_mport(struct device
mutex_init(&cm->rx_lock);
riocm_rx_fill(cm, RIOCM_RX_RING_SIZE);
cm->rx_wq = create_workqueue(DRV_NAME "/rxq");
- if (!cm->rx_wq) {
- riocm_error("failed to allocate IBMBOX_%d on %s",
- cmbox, mport->name);
- rio_release_outb_mbox(mport, cmbox);
- kfree(cm);
- return -ENOMEM;
- }
-
INIT_WORK(&cm->rx_work, rio_ibmsg_handler);

cm->tx_slot = 0;