aboutsummaryrefslogtreecommitdiff
path: root/drivers/block/xen-blkfront.c
diff options
context:
space:
mode:
authorRoger Pau Monne <roger.pau@citrix.com>2012-12-04 15:21:53 +0100
committerKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>2012-12-17 21:55:56 -0500
commitebb351cf78ee6bf3262e6b4b6906f456c05e6d5e (patch)
tree103c6133d51f266b16c8b6f71fddf4992c57dc8f /drivers/block/xen-blkfront.c
parent7dc341175af5e7361af81499ea192c7b274b6357 (diff)
downloadlinux-ebb351cf78ee6bf3262e6b4b6906f456c05e6d5e.tar.gz
llist/xen-blkfront: implement safe version of llist_for_each_entry
Implement a safe version of llist_for_each_entry, and use it in blkif_free. Previously grants where freed while iterating the list, which lead to dereferences when trying to fetch the next item. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> [v2: Move the llist_for_each_entry_safe in llist.h] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'drivers/block/xen-blkfront.c')
-rw-r--r--drivers/block/xen-blkfront.c3
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 96e9b00db08..cfdb033c710 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -792,6 +792,7 @@ static void blkif_free(struct blkfront_info *info, int suspend)
{
struct llist_node *all_gnts;
struct grant *persistent_gnt;
+ struct llist_node *n;
/* Prevent new requests being issued until we fix things up. */
spin_lock_irq(&info->io_lock);
@@ -804,7 +805,7 @@ static void blkif_free(struct blkfront_info *info, int suspend)
/* Remove all persistent grants */
if (info->persistent_gnts_c) {
all_gnts = llist_del_all(&info->persistent_gnts);
- llist_for_each_entry(persistent_gnt, all_gnts, node) {
+ llist_for_each_entry_safe(persistent_gnt, n, all_gnts, node) {
gnttab_end_foreign_access(persistent_gnt->gref, 0, 0UL);
__free_page(pfn_to_page(persistent_gnt->pfn));
kfree(persistent_gnt);