[SCSI] ibmvfc: Fix DMA mapping leak on memory allocation failure

There is currently a DMA mapping leak that can occur in the ibmvfc
driver if we fail to allocate a scatterlist. Fix this by unmapping
the scatterlist in the failure path. Additionally, only log an error
for a scatterlist allocation failure if the log level is greater
than the default, since this can occur when running Active Memory
Sharing and this is not considered an error.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index 91ef669d98f6..a1a511bdec8c 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -1322,7 +1322,9 @@ static int ibmvfc_map_sg_data(struct scsi_cmnd *scmd,
                                                &evt->ext_list_token);
 
                 if (!evt->ext_list) {
-                        scmd_printk(KERN_ERR, scmd, "Can't allocate memory for scatterlist\n");
+                        scsi_dma_unmap(scmd);
+                        if (vhost->log_level > IBMVFC_DEFAULT_LOG_LEVEL)
+                                scmd_printk(KERN_ERR, scmd, "Can't allocate memory for scatterlist\n");
                         return -ENOMEM;
                 }
         }