4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Alexander Potapenko <glider@xxxxxxxxxx>
[ Upstream commit d515684d78148884d5fc425ba904c50f03844020 ]
In the case udp_sk(sk)->pending is AF_INET6, udpv6_sendmsg() would
jump to do_append_data, skipping the initialization of sockc.tsflags.
Fix the problem by moving sockc.tsflags initialization earlier.
The bug was detected with KMSAN.
Fixes: c14ac9451c34 ("sock: enable timestamping using control messages")
Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx>
Acked-by: Soheil Hassas Yeganeh <soheil@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv6/udp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1037,6 +1037,7 @@ int udpv6_sendmsg(struct sock *sk, struc
ipc6.hlimit = -1;
ipc6.tclass = -1;
ipc6.dontfrag = -1;
+ sockc.tsflags = sk->sk_tsflags;
/* destination address check */
if (sin6) {
@@ -1156,7 +1157,6 @@ do_udp_sendmsg:
fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
fl6.flowi6_mark = sk->sk_mark;
- sockc.tsflags = sk->sk_tsflags;
if (msg->msg_controllen) {
opt = &opt_space;