[PATCH AUTOSEL for 3.18 19/40] irda: vlsi_ir: fix check for DMA mapping errors

[alexander . levin]

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

diff --git a/drivers/net/irda/vlsi_ir.c b/drivers/net/irda/vlsi_ir.c
index a2e556168286..aceedd7aeb2a 100644
--- a/drivers/net/irda/vlsi_ir.c
+++ b/drivers/net/irda/vlsi_ir.c
@@ -426,8 +426,9 @@ static struct vlsi_ring *vlsi_alloc_ring(struct pci_dev 
*pdev, struct ring_descr
                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) {
                                IRDA_ERROR("%s: failed to create PCI-MAP for 
%p",
                                           __func__, rd->buf);
@@ -438,8 +439,7 @@ static struct vlsi_ring *vlsi_alloc_ring(struct pci_dev 
*pdev, struct ring_descr
                                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;
                        }
-- 
2.11.0