[PATCH 5.10.y] scsi: ufs: core: Improve SCSI abort handling

[Vasiliy Kovalev <kovalev@altlinux.org>]

From: Bart Van Assche <bvanassche@acm.org>

commit 3ff1f6b6ba6f97f50862aa50e79959cc8ddc2566 upstream.

The following has been observed on a test setup:

WARNING: CPU: 4 PID: 250 at drivers/scsi/ufs/ufshcd.c:2737 ufshcd_queuecommand+0x468/0x65c
Call trace:
 ufshcd_queuecommand+0x468/0x65c
 scsi_send_eh_cmnd+0x224/0x6a0
 scsi_eh_test_devices+0x248/0x418
 scsi_eh_ready_devs+0xc34/0xe58
 scsi_error_handler+0x204/0x80c
 kthread+0x150/0x1b4
 ret_from_fork+0x10/0x30

That warning is triggered by the following statement:

	WARN_ON(lrbp->cmd);

Fix this warning by clearing lrbp->cmd from the abort handler.

Link: https://lore.kernel.org/r/20211104181059.4129537-1-bvanassche@acm.org
Fixes: 7a3e97b0dc4b ("[SCSI] ufshcd: UFS Host controller driver")
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
[ kovalev: bp to fix CVE-2021-47188; adapted placement of
  lrbp->cmd = NULL for 5.10 function structure ]
Signed-off-by: Vasiliy Kovalev <kovalev@altlinux.org>
---
 drivers/scsi/ufs/ufshcd.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index c7bf0e6bc303..1b8072f47e7e 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -6788,6 +6788,7 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
 		__ufshcd_transfer_req_compl(hba, (1UL << tag));
 		spin_unlock_irqrestore(host->host_lock, flags);
 out:
+		lrbp->cmd = NULL;
 		err = SUCCESS;
 	} else {
 		dev_err(hba->dev, "%s: failed with err %d\n", __func__, err);
-- 
2.50.1