diff mbox

[5/7] scsi: storvsc: Fix a bug in copy_from_bounce_buffer()

Message ID 1427144801-11920-5-git-send-email-kys@microsoft.com (mailing list archive)
State New, archived
Headers show

Commit Message

KY Srinivasan March 23, 2015, 9:06 p.m. UTC
We may exit this function without properly freeing up the maapings
we may have acquired. Fix the bug.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
---
 drivers/scsi/storvsc_drv.c |   15 ++++++++-------
 1 files changed, 8 insertions(+), 7 deletions(-)

Comments

Long Li March 23, 2015, 8:52 p.m. UTC | #1
> -----Original Message-----
> From: devel [mailto:driverdev-devel-bounces@linuxdriverproject.org] On
> Behalf Of K. Y. Srinivasan
> Sent: Monday, March 23, 2015 2:07 PM
> To: gregkh@linuxfoundation.org; linux-kernel@vger.kernel.org;
> devel@linuxdriverproject.org; ohering@suse.com; jbottomley@parallels.com;
> hch@infradead.org; linux-scsi@vger.kernel.org; apw@canonical.com;
> vkuznets@redhat.com; jasowang@redhat.com
> Cc: stable@vger.kernel.org
> Subject: [PATCH 5/7] scsi: storvsc: Fix a bug in copy_from_bounce_buffer()
> 
> We may exit this function without properly freeing up the maapings we may
> have acquired. Fix the bug.
> 
> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Long Li <longli@microsoft.com>

> Cc: <stable@vger.kernel.org>
> ---
>  drivers/scsi/storvsc_drv.c |   15 ++++++++-------
>  1 files changed, 8 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index
> 5c13eec..88f5d79 100644
> --- a/drivers/scsi/storvsc_drv.c
> +++ b/drivers/scsi/storvsc_drv.c
> @@ -754,21 +754,22 @@ static unsigned int copy_to_bounce_buffer(struct
> scatterlist *orig_sgl,
>  			if (bounce_sgl[j].length == PAGE_SIZE) {
>  				/* full..move to next entry */
>  				sg_kunmap_atomic(bounce_addr);
> +				bounce_addr = 0;
>  				j++;
> +			}
> 
> -				/* if we need to use another bounce buffer */
> -				if (srclen || i != orig_sgl_count - 1)
> -					bounce_addr =
> sg_kmap_atomic(bounce_sgl,j);
> +			/* if we need to use another bounce buffer */
> +			if (srclen && bounce_addr == 0)
> +				bounce_addr = sg_kmap_atomic(bounce_sgl,
> j);
> 
> -			} else if (srclen == 0 && i == orig_sgl_count - 1) {
> -				/* unmap the last bounce that is < PAGE_SIZE
> */
> -				sg_kunmap_atomic(bounce_addr);
> -			}
>  		}
> 
>  		sg_kunmap_atomic(src_addr - orig_sgl[i].offset);
>  	}
> 
> +	if (bounce_addr)
> +		sg_kunmap_atomic(bounce_addr);
> +
>  	local_irq_restore(flags);
> 
>  	return total_copied;
> --
> 1.7.4.1
> 
> _______________________________________________
> devel mailing list
> devel@linuxdriverproject.org
> http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index 5c13eec..88f5d79 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -754,21 +754,22 @@  static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl,
 			if (bounce_sgl[j].length == PAGE_SIZE) {
 				/* full..move to next entry */
 				sg_kunmap_atomic(bounce_addr);
+				bounce_addr = 0;
 				j++;
+			}
 
-				/* if we need to use another bounce buffer */
-				if (srclen || i != orig_sgl_count - 1)
-					bounce_addr = sg_kmap_atomic(bounce_sgl,j);
+			/* if we need to use another bounce buffer */
+			if (srclen && bounce_addr == 0)
+				bounce_addr = sg_kmap_atomic(bounce_sgl, j);
 
-			} else if (srclen == 0 && i == orig_sgl_count - 1) {
-				/* unmap the last bounce that is < PAGE_SIZE */
-				sg_kunmap_atomic(bounce_addr);
-			}
 		}
 
 		sg_kunmap_atomic(src_addr - orig_sgl[i].offset);
 	}
 
+	if (bounce_addr)
+		sg_kunmap_atomic(bounce_addr);
+
 	local_irq_restore(flags);
 
 	return total_copied;