[PATCH 4.4 45/78] irda: vlsi_ir: fix check for DMA mapping errors

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Alexey Khoroshilov <khoroshi...@ispras.ru>


[ 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).

Signed-off-by: Alexey Khoroshilov <khoroshi...@ispras.ru>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Sasha Levin <alexander.le...@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 drivers/net/irda/vlsi_ir.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/net/irda/vlsi_ir.c
+++ b/drivers/net/irda/vlsi_ir.c
@@ -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;
                        }