[Devel] [PATCH vz7] ploop: fix typo in ploop_pb_get_first_req_from_tree

[Maxim Patlasov]

Due to a typo, local pointer was defined as static leading to a nasty race:

1. Thread A (handling ploopN) initializes that pointer
2. Thread B (handling ploopM) re-initialize the same pointer
3. Thread A proceeds with using the pointer that currently points to
some request belonging to ploopM.

Hence data (ploop requests) leaked from one ploop device to another
leading to list corruption.

https://jira.sw.ru/browse/PSBM-67513

Signed-off-by: Maxim Patlasov <mpatlasov at virtuozzo.com>
---
 drivers/block/ploop/push_backup.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/ploop/push_backup.c b/drivers/block/ploop/push_backup.c
index ade5fa5..032706e 100644
--- a/drivers/block/ploop/push_backup.c
+++ b/drivers/block/ploop/push_backup.c
@@ -598,7 +598,7 @@ ploop_pb_get_first_req_from_tree(struct pb_set *pbs,
 				 unsigned old_owner)
 {
 	struct rb_root *tree = &pbs->tree;
-	static struct ploop_request *p;
+	struct ploop_request *p;
 	struct rb_node *n = rb_first(tree);
 
 	if (!n)