4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
commit 11d49e9d089ccec81be87c2386dfdd010d7f7f6e upstream.
we are advancing sg as we go, so the pages we need to drop in
case of error are *before* the current sg.
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/vhost/scsi.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -693,6 +693,7 @@ vhost_scsi_iov_to_sgl(struct vhost_scsi_
struct scatterlist *sg, int sg_count)
{
size_t off = iter->iov_offset;
+ struct scatterlist *p = sg;
int i, ret;
for (i = 0; i < iter->nr_segs; i++) {
@@ -701,8 +702,8 @@ vhost_scsi_iov_to_sgl(struct vhost_scsi_
ret = vhost_scsi_map_to_sgl(cmd, base, len, sg, write);
if (ret < 0) {
- for (i = 0; i < sg_count; i++) {
- struct page *page = sg_page(&sg[i]);
+ while (p < sg) {
+ struct page *page = sg_page(p++);
if (page)
put_page(page);
}