Patch "irda: vlsi_ir: fix check for DMA mapping errors" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

irda: vlsi_ir: fix check for DMA mapping errors

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
irda-vlsi_ir-fix-check-for-dma-mapping-errors.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Alexey Khoroshilov <[email protected]>
Date: Sat, 25 Mar 2017 01:48:08 +0300
Subject: irda: vlsi_ir: fix check for DMA mapping errors

From: Alexey Khoroshilov <[email protected]>

[ Upstream commit 6ac3b77a6ffff7513ff86b684aa256ea01c0e5b5 ]

vlsi_alloc_ring() checks for DMA mapping errors by comparing returned address with zero, while pci_dma_mapping_error() should be used.

Found by Linux Driver Verification project (linuxtesting.org).

---
 drivers/net/irda/vlsi_ir.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

@@ -418,8 +418,9 @@ static struct vlsi_ring *vlsi_alloc_ring
 		memset(rd, 0, sizeof(*rd));
 		rd->hw = hwmap + i;
 		rd->buf = kmalloc(len, GFP_KERNEL|GFP_DMA);
-		if (rd->buf == NULL ||
-		    !(busaddr = pci_map_single(pdev, rd->buf, len, dir))) {
+		if (rd->buf)
+			busaddr = pci_map_single(pdev, rd->buf, len, dir);
+		if (rd->buf == NULL || pci_dma_mapping_error(pdev, busaddr)) {
 			if (rd->buf) {
 				net_err_ratelimited("%s: failed to create PCI-MAP for %p\n",
 						    __func__, rd->buf);

@@ -430,8 +431,7 @@ static struct vlsi_ring *vlsi_alloc_ring
 				rd = r->rd + j;
 				busaddr = rd_get_addr(rd);
 				rd_set_addr_status(rd, 0, 0);
-				if (busaddr)
-					pci_unmap_single(pdev, busaddr, len, dir);
+				pci_unmap_single(pdev, busaddr, len, dir);
 				kfree(rd->buf);
 				rd->buf = NULL;
 			}

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/irda-vlsi_ir-fix-check-for-dma-mapping-errors.patch