FAILED: patch "[PATCH] scsi: qla2xxx: Fix use-after-free of qpair work on queue" failed to apply to 6.12-stable tree

FAILED: patch "[PATCH] scsi: qla2xxx: Fix use-after-free of qpair work on queue" failed to apply to 6.12-stable tree

[gregkh]

The patch below does not apply to the 6.12-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 <stable@vger.kernel.org>.

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-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 19788a55cab61d78e33e0914a5a31d27843e8a4a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026090919-divided-onion-9b49@gregkh' --subject-prefix 'PATCH 6.12.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

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

From 19788a55cab61d78e33e0914a5a31d27843e8a4a Mon Sep 17 00:00:00 2001
From: Nilesh Javali <njavali@marvell.com>
Date: Thu, 30 Jul 2026 21:28:09 +0530
Subject: [PATCH] scsi: qla2xxx: Fix use-after-free of qpair work on queue
 teardown

The response queue MSI-X handler qla2xxx_msix_rsp_q() schedules
qla_do_work() via queue_work(ha->wq, &qpair->q_work). qla_do_work()
dereferences the qpair (vha, rsp) and takes qpair->qp_lock.

During teardown, qla2xxx_delete_qpair() deletes the response queue, which
calls free_irq() in qla25xx_free_rsp_que(), and then frees the queue and
the qpair. free_irq() waits for running hardirq handlers but does not
cancel work already placed on ha->wq. A still-pending q_work then runs
qla_do_work() against the freed qpair and response queue, causing a
use-after-free. This is especially likely during full adapter teardown,
where destroy_workqueue(ha->wq) forces pending work to run after the queue
pairs have been freed.

Flush the work item with cancel_work_sync() in qla25xx_free_rsp_que()
after free_irq() has released the interrupt (so no new work can be
queued) and before the response queue and qpair memory are freed (so the
flushed handler still sees valid memory). Guard on rsp->qpair and ha->wq
to match the INIT_WORK() condition and avoid operating on an
uninitialized work_struct.

Fixes: 68ca949cdb04 ("[SCSI] qla2xxx: Add CPU affinity support.")
Reported-by: Sashiko <sashiko-dev@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Link: https://patch.msgid.link/20260730155838.2119230-5-njavali@marvell.com
Signed-off-by: Martin K. Petersen (Oracle) <mkp@kernel.org>

diff --git a/drivers/scsi/qla2xxx/qla_mid.c b/drivers/scsi/qla2xxx/qla_mid.c
index b7d9c1a53f3c..33bfc61d8165 100644
--- a/drivers/scsi/qla2xxx/qla_mid.c
+++ b/drivers/scsi/qla2xxx/qla_mid.c
@@ -606,6 +606,10 @@ qla25xx_free_rsp_que(struct scsi_qla_host *vha, struct rsp_que *rsp)
 		rsp->msix->handle = NULL;
 	}
 
+	/* Flush any queued response work before freeing the queue/qpair. */
+	if (rsp->qpair && ha->wq)
+		cancel_work_sync(&rsp->qpair->q_work);
+
 	if (rsp->ring)
 		dma_free_coherent(&ha->pdev->dev,
 				  (rsp->length + 1) * rsp_entry_size,

[PATCH 6.12.y 1/2] scsi: qla2xxx: Fix queue teardown NULL dma_free and bitmap locking

[Sasha Levin]

From: Nilesh Javali <njavali@marvell.com>

[ Upstream commit 34a40e0dff940ac5eba494a69b553ea571e24873 ]

qla25xx_free_req_que() and qla25xx_free_rsp_que() have two pre-existing
bugs exposed on the error path of qla25xx_create_{req,rsp}_que():

 1. When dma_alloc_coherent() fails during queue creation, the error
    path calls the free function with req->ring / rsp->ring still NULL
    (from kzalloc).  The unconditional dma_free_coherent() with a NULL
    cpu_addr is undefined behavior and can panic.

 2. The free functions clear req_qid_map / rsp_qid_map under vport_lock,
    but the create functions protect the same bitmaps with mq_lock.
    This provides no mutual exclusion.  Additionally, the create error
    path clears the bit and releases mq_lock before calling the free
    function, creating a window where another thread can allocate the
    same que_id and have its ha->req_q_map entry clobbered by the
    subsequent lockless NULL assignment in the free function.

Fix by:

 - Guarding dma_free_coherent() with a NULL check on the ring pointer.

 - Using mq_lock (the lock held by all creators) in the free functions
   to atomically NULL the map entry and clear the bitmap bit.

 - Removing the now-redundant clear_bit blocks from the create error
   paths since the free functions handle it atomically.

Signed-off-by: Nilesh Javali <njavali@marvell.com>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Link: https://patch.msgid.link/20260723050413.3897522-41-njavali@marvell.com
Signed-off-by: Martin K. Petersen (Oracle) <mkp@kernel.org>

Backport adaptation for the stable tree: the 29xx IOCB size-selection
helpers are absent, and queue creation still allocates fixed-size entries.
Initialize the local req_entry_size and rsp_entry_size values with
sizeof(request_t) and sizeof(response_t), respectively, so DMA freeing
continues to match allocation without adding helper functions or 29xx
support. Retain all NULL-ring guards, mq_lock protection, and removal of
the premature bitmap clears.

Keep the response-ring cleanup layout used by upstream so target commit
19788a55cab61d78e33e0914a5a31d27843e8a4a applies unchanged.

Stable-dep-of: 19788a55cab6 ("scsi: qla2xxx: Fix use-after-free of qpair work on queue teardown")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/scsi/qla2xxx/qla_mid.c | 29 +++++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/drivers/scsi/qla2xxx/qla_mid.c b/drivers/scsi/qla2xxx/qla_mid.c
index 9946899dd83b8..61570f032a8ac 100644
--- a/drivers/scsi/qla2xxx/qla_mid.c
+++ b/drivers/scsi/qla2xxx/qla_mid.c
@@ -574,16 +574,19 @@ qla25xx_free_req_que(struct scsi_qla_host *vha, struct req_que *req)
 {
 	struct qla_hw_data *ha = vha->hw;
 	uint16_t que_id = req->id;
+	size_t req_entry_size = sizeof(request_t);
 
-	dma_free_coherent(&ha->pdev->dev, (req->length + 1) *
-		sizeof(request_t), req->ring, req->dma);
+	if (req->ring)
+		dma_free_coherent(&ha->pdev->dev,
+				  (req->length + 1) * req_entry_size,
+				  req->ring, req->dma);
 	req->ring = NULL;
 	req->dma = 0;
 	if (que_id) {
+		mutex_lock(&ha->mq_lock);
 		ha->req_q_map[que_id] = NULL;
-		mutex_lock(&ha->vport_lock);
 		clear_bit(que_id, ha->req_qid_map);
-		mutex_unlock(&ha->vport_lock);
+		mutex_unlock(&ha->mq_lock);
 	}
 	kfree(req->outstanding_cmds);
 	kfree(req);
@@ -594,6 +597,7 @@ qla25xx_free_rsp_que(struct scsi_qla_host *vha, struct rsp_que *rsp)
 {
 	struct qla_hw_data *ha = vha->hw;
 	uint16_t que_id = rsp->id;
+	size_t rsp_entry_size = sizeof(response_t);
 
 	if (rsp->msix && rsp->msix->have_irq) {
 		free_irq(rsp->msix->vector, rsp->msix->handle);
@@ -601,15 +605,18 @@ qla25xx_free_rsp_que(struct scsi_qla_host *vha, struct rsp_que *rsp)
 		rsp->msix->in_use = 0;
 		rsp->msix->handle = NULL;
 	}
-	dma_free_coherent(&ha->pdev->dev, (rsp->length + 1) *
-		sizeof(response_t), rsp->ring, rsp->dma);
+
+	if (rsp->ring)
+		dma_free_coherent(&ha->pdev->dev,
+				  (rsp->length + 1) * rsp_entry_size,
+				  rsp->ring, rsp->dma);
 	rsp->ring = NULL;
 	rsp->dma = 0;
 	if (que_id) {
+		mutex_lock(&ha->mq_lock);
 		ha->rsp_q_map[que_id] = NULL;
-		mutex_lock(&ha->vport_lock);
 		clear_bit(que_id, ha->rsp_qid_map);
-		mutex_unlock(&ha->vport_lock);
+		mutex_unlock(&ha->mq_lock);
 	}
 	kfree(rsp);
 }
@@ -794,9 +801,6 @@ qla25xx_create_req_que(struct qla_hw_data *ha, uint16_t options,
 		if (ret != QLA_SUCCESS) {
 			ql_log(ql_log_fatal, base_vha, 0x00df,
 			    "%s failed.\n", __func__);
-			mutex_lock(&ha->mq_lock);
-			clear_bit(que_id, ha->req_qid_map);
-			mutex_unlock(&ha->mq_lock);
 			goto que_failed;
 		}
 		vha->flags.qpairs_req_created = 1;
@@ -908,9 +912,6 @@ qla25xx_create_rsp_que(struct qla_hw_data *ha, uint16_t options,
 		if (ret != QLA_SUCCESS) {
 			ql_log(ql_log_fatal, base_vha, 0x00e7,
 			    "%s failed.\n", __func__);
-			mutex_lock(&ha->mq_lock);
-			clear_bit(que_id, ha->rsp_qid_map);
-			mutex_unlock(&ha->mq_lock);
 			goto que_failed;
 		}
 		vha->flags.qpairs_rsp_created = 1;
-- 
2.53.0

[PATCH 6.12.y 2/2] scsi: qla2xxx: Fix use-after-free of qpair work on queue teardown

[Sasha Levin]

From: Nilesh Javali <njavali@marvell.com>

[ Upstream commit 19788a55cab61d78e33e0914a5a31d27843e8a4a ]

The response queue MSI-X handler qla2xxx_msix_rsp_q() schedules
qla_do_work() via queue_work(ha->wq, &qpair->q_work). qla_do_work()
dereferences the qpair (vha, rsp) and takes qpair->qp_lock.

During teardown, qla2xxx_delete_qpair() deletes the response queue, which
calls free_irq() in qla25xx_free_rsp_que(), and then frees the queue and
the qpair. free_irq() waits for running hardirq handlers but does not
cancel work already placed on ha->wq. A still-pending q_work then runs
qla_do_work() against the freed qpair and response queue, causing a
use-after-free. This is especially likely during full adapter teardown,
where destroy_workqueue(ha->wq) forces pending work to run after the queue
pairs have been freed.

Flush the work item with cancel_work_sync() in qla25xx_free_rsp_que()
after free_irq() has released the interrupt (so no new work can be
queued) and before the response queue and qpair memory are freed (so the
flushed handler still sees valid memory). Guard on rsp->qpair and ha->wq
to match the INIT_WORK() condition and avoid operating on an
uninitialized work_struct.

Fixes: 68ca949cdb04 ("[SCSI] qla2xxx: Add CPU affinity support.")
Reported-by: Sashiko <sashiko-dev@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Link: https://patch.msgid.link/20260730155838.2119230-5-njavali@marvell.com
Signed-off-by: Martin K. Petersen (Oracle) <mkp@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/scsi/qla2xxx/qla_mid.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/scsi/qla2xxx/qla_mid.c b/drivers/scsi/qla2xxx/qla_mid.c
index 61570f032a8ac..44dd9373bfb12 100644
--- a/drivers/scsi/qla2xxx/qla_mid.c
+++ b/drivers/scsi/qla2xxx/qla_mid.c
@@ -606,6 +606,10 @@ qla25xx_free_rsp_que(struct scsi_qla_host *vha, struct rsp_que *rsp)
 		rsp->msix->handle = NULL;
 	}
 
+	/* Flush any queued response work before freeing the queue/qpair. */
+	if (rsp->qpair && ha->wq)
+		cancel_work_sync(&rsp->qpair->q_work);
+
 	if (rsp->ring)
 		dma_free_coherent(&ha->pdev->dev,
 				  (rsp->length + 1) * rsp_entry_size,
-- 
2.53.0