[PATCH AUTOSEL 4.19 04/83] pvcalls-front: don't try to free unallocated rings

Sasha Levin
2019-02-13T02:57:24Z

From: Stefano Stabellini <sstabellini@kernel.org>

[ Upstream commit 96283f9a084e23d7cda2d3c5d1ffa6df6cf1ecec ]

inflight_req_id is 0 when initialized. If inflight_req_id is 0, there is
no accept_map to free. Fix the check in pvcalls_front_release.

Signed-off-by: Stefano Stabellini <stefanos@xilinx.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/xen/pvcalls-front.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c
index e5d95aab2cb8..4f3d664b3f39 100644
--- a/drivers/xen/pvcalls-front.c
+++ b/drivers/xen/pvcalls-front.c
@@ -1030,8 +1030,8 @@ int pvcalls_front_release(struct socket *sock)
spin_lock(&bedata->socket_lock);
list_del(&map->list);
spin_unlock(&bedata->socket_lock);
- if (READ_ONCE(map->passive.inflight_req_id) !=
- PVCALLS_INVALID_ID) {
+ if (READ_ONCE(map->passive.inflight_req_id) != PVCALLS_INVALID_ID &&
+ READ_ONCE(map->passive.inflight_req_id) != 0) {
pvcalls_front_free_map(bedata,
map->passive.accept_map);
}
--
2.19.1