[PATCH] snic: Fix use-after-free in case of a dma mapping error

From: Johannes Thumshirn
Date: Thu Jun 23 2016 - 08:37:37 EST


If there is a dma mapping error snic kfree()s buf right before printing it.
Change the order to not accidently trip on memory that's not owned by us
anymore.

Signed-off-by: Johannes Thumshirn <jthumshirn@xxxxxxx>
---
drivers/scsi/snic/snic_disc.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/snic/snic_disc.c b/drivers/scsi/snic/snic_disc.c
index b0fefd6..b106596 100644
--- a/drivers/scsi/snic/snic_disc.c
+++ b/drivers/scsi/snic/snic_disc.c
@@ -113,11 +113,11 @@ snic_queue_report_tgt_req(struct snic *snic)

pa = pci_map_single(snic->pdev, buf, buf_len, PCI_DMA_FROMDEVICE);
if (pci_dma_mapping_error(snic->pdev, pa)) {
- kfree(buf);
- snic_req_free(snic, rqi);
SNIC_HOST_ERR(snic->shost,
"Rpt-tgt rspbuf %p: PCI DMA Mapping Failed\n",
buf);
+ kfree(buf);
+ snic_req_free(snic, rqi);
ret = -EINVAL;

goto error;
--
2.8.4