From b60bb6e2bfc192091b8f792781b83b5e0f9324f6 Mon Sep 17 00:00:00 2001

From: Dave Jiang <dave.jiang@intel.com>

Date: Thu, 22 Jul 2021 13:10:51 -0700

Subject: [PATCH] dmaengine: idxd: fix abort status check

Git-commit: b60bb6e2bfc192091b8f792781b83b5e0f9324f6

Patch-mainline: v5.15-rc1

References: git-fixes stable-5.14.8

Coverity static analysis of linux-next found issue.

The check (status == IDXD_COMP_DESC_ABORT) is always false since status

was previously masked with 0x7f and IDXD_COMP_DESC_ABORT is 0xff.

Fixes: 6b4b87f2c31a ("dmaengine: idxd: fix submission race window")

Reported-by: Colin Ian King <colin.king@canonical.com>

Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Link: https://lore.kernel.org/r/162698465160.3560828.18173186265683415384.stgit@djiang5-desk3.ch.intel.com

Signed-off-by: Vinod Koul <vkoul@kernel.org>

Acked-by: Takashi Iwai <tiwai@suse.de>

---

 drivers/dma/idxd/irq.c | 12 ++++++++++--

 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/idxd/irq.c b/drivers/dma/idxd/irq.c

index e018459b534f..65dc7bbb0a13 100644

--- a/drivers/dma/idxd/irq.c

+++ b/drivers/dma/idxd/irq.c

@@ -194,7 +194,11 @@ static int irq_process_pending_llist(struct idxd_irq_entry *irq_entry,

 		u8 status = desc->completion->status & DSA_COMP_STATUS_MASK;

 		if (status) {

-			if (unlikely(status == IDXD_COMP_DESC_ABORT)) {

+			/*

+			 * Check against the original status as ABORT is software defined

+			 * and 0xff, which DSA_COMP_STATUS_MASK can mask out.

+			 */

+			if (unlikely(desc->completion->status == IDXD_COMP_DESC_ABORT)) {

 				complete_desc(desc, IDXD_COMPLETE_ABORT);

 				(*processed)++;

 				continue;

@@ -250,7 +254,11 @@ static int irq_process_work_list(struct idxd_irq_entry *irq_entry,

 	list_for_each_entry(desc, &flist, list) {

 		u8 status = desc->completion->status & DSA_COMP_STATUS_MASK;

-		if (unlikely(status == IDXD_COMP_DESC_ABORT)) {

+		/*

+		 * Check against the original status as ABORT is software defined

+		 * and 0xff, which DSA_COMP_STATUS_MASK can mask out.

+		 */

+		if (unlikely(desc->completion->status == IDXD_COMP_DESC_ABORT)) {

 			complete_desc(desc, IDXD_COMPLETE_ABORT);

 			continue;

 		}

-- 

2.26.2