[PATCH] move smp_rmb() after load of status

From: humbabek
Date: Sat Jul 07 2018 - 15:23:44 EST


Signed-off-by: humbabek <humbabek@xxxxxxxxx>
---
net/packet/af_packet.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 57634bc3da74..91830ef07c48 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -394,25 +394,30 @@ static void __packet_set_status(struct packet_sock *po, void *frame, int status)
static int __packet_get_status(struct packet_sock *po, void *frame)
{
union tpacket_uhdr h;
-
- smp_rmb();
+ int status;

h.raw = frame;
switch (po->tp_version) {
case TPACKET_V1:
flush_dcache_page(pgv_to_page(&h.h1->tp_status));
- return h.h1->tp_status;
+ status = h.h1->tp_status;
+ break;
case TPACKET_V2:
flush_dcache_page(pgv_to_page(&h.h2->tp_status));
- return h.h2->tp_status;
+ status = h.h2->tp_status;
+ break;
case TPACKET_V3:
flush_dcache_page(pgv_to_page(&h.h3->tp_status));
- return h.h3->tp_status;
+ status = h.h3->tp_status;
+ break;
default:
WARN(1, "TPACKET version not supported.\n");
BUG();
- return 0;
+ status = 0;
+ break;
}
+ smp_rmb();
+ return status;
}

static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
--
2.17.1