[PATCH 4.20 023/183] pvcalls-front: properly allocate sk

From: Greg Kroah-Hartman
Date: Mon Feb 25 2019 - 16:43:57 EST


4.20-stable review patch. If anyone has any objections, please let me know.

------------------

[ Upstream commit beee1fbe8f7d57d6ebaa5188f9f4db89c2077196 ]

Don't use kzalloc: it ends up leaving sk->sk_prot not properly
initialized. Use sk_alloc instead and define our own trivial struct
proto.

Signed-off-by: Stefano Stabellini <stefanos@xxxxxxxxxx>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/xen/pvcalls-front.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c
index 4f3d664b3f39e..01588582ae663 100644
--- a/drivers/xen/pvcalls-front.c
+++ b/drivers/xen/pvcalls-front.c
@@ -31,6 +31,12 @@
#define PVCALLS_NR_RSP_PER_RING __CONST_RING_SIZE(xen_pvcalls, XEN_PAGE_SIZE)
#define PVCALLS_FRONT_MAX_SPIN 5000

+static struct proto pvcalls_proto = {
+ .name = "PVCalls",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct sock),
+};
+
struct pvcalls_bedata {
struct xen_pvcalls_front_ring ring;
grant_ref_t ref;
@@ -837,7 +843,7 @@ int pvcalls_front_accept(struct socket *sock, struct socket *newsock, int flags)

received:
map2->sock = newsock;
- newsock->sk = kzalloc(sizeof(*newsock->sk), GFP_KERNEL);
+ newsock->sk = sk_alloc(sock_net(sock->sk), PF_INET, GFP_KERNEL, &pvcalls_proto, false);
if (!newsock->sk) {
bedata->rsp[req_id].req_id = PVCALLS_INVALID_ID;
map->passive.inflight_req_id = PVCALLS_INVALID_ID;
--
2.19.1