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drbd: null dereference bug

PATCH In review Dan Carpenter 2 participants 2 messages Jan 23, 2010 – Jan 25, 2010

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Dan Carpenter

author
#0 lore raw

PATCH 1/1 drbd: null dereference bug

epoch is always NULL here.

Signed-off-by Dan Carpenter <[email protected]>

---
This patch has only been compile tested. Sorry. :/

drivers/block/drbd/drbd_receiver.c +1 -1
@@ -1224,7 +1224,7 @@ static int receive_Barrier(struct drbd_c
 	epoch = kmalloc(sizeof(struct drbd_epoch), GFP_NOIO);
 	if (!epoch) {
 		dev_warn(DEV, "Allocation of an epoch failed, slowing down\n");
-		issue_flush = !test_and_set_bit(DE_BARRIER_IN_NEXT_EPOCH_ISSUED, &epoch->flags);
+		issue_flush = !test_and_set_bit(DE_BARRIER_IN_NEXT_EPOCH_ISSUED, &mdev->current_epoch->flags);
 		drbd_wait_ee_list_empty(mdev, &mdev->active_ee);
 		if (issue_flush) {
 			rv = drbd_flush_after_epoch(mdev, mdev->current_epoch);
maintainer
#1 lore raw

Am Samstag, 23. Januar 2010 13:45:22 schrieb Dan Carpenter:

Quoted 11 lines

epoch is always NULL here.

Signed-off-by Dan Carpenter <[email protected]>

---
This patch has only been compile tested. Sorry. :/

--- orig/drivers/block/drbd/drbd_receiver.c 2010-01-23 10:53:13.000000000
+0300 +++ devel/drivers/block/drbd/drbd_receiver.c 2010-01-23
10:54:19.000000000 +0300 @@ -1224,7 +1224,7 @@ static int receive_Barrier(struct drbd_c

drivers/block/drbd/drbd_receiver.c static int receive_Barrier(struct drbd_c · line 1230

Quoted 8 lines
drivers/block/drbd/drbd_receiver.c +1 -1
 	epoch = kmalloc(sizeof(struct drbd_epoch), GFP_NOIO);
 	if (!epoch) {
 		dev_warn(DEV, "Allocation of an epoch failed, slowing down\n");
-		issue_flush = !test_and_set_bit(DE_BARRIER_IN_NEXT_EPOCH_ISSUED, &epoch->flags);
+		issue_flush = !test_and_set_bit(DE_BARRIER_IN_NEXT_EPOCH_ISSUED, &mdev->current_epoch->flags);
 		drbd_wait_ee_list_empty(mdev, &mdev->active_ee);
 		if (issue_flush) {
 			rv = drbd_flush_after_epoch(mdev, mdev->current_epoch);

The patch is correct. It is going upstream though the DRBD tree. See:
http://git.drbd.org/?p=linux-2.6-drbd.git;a=commit;h=d3db7b485ad7c467a61279d6a8ef51a3c83352df

-Phil

Signature · 6 lines
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