From: Niels Dossche dossche.niels@gmail.com
[ Upstream commit 6c0d8833a605e195ae219b5042577ce52bf71fff ]
valid_lft, prefered_lft and tstamp are always accessed under the lock "lock" in other places. Reading these without taking the lock may result in inconsistencies regarding the calculation of the valid and preferred variables since decisions are taken on these fields for those variables.
Signed-off-by: Niels Dossche dossche.niels@gmail.com Reviewed-by: David Ahern dsahern@kernel.org Signed-off-by: Niels Dossche niels.dossche@ugent.be Link: https://lore.kernel.org/r/20220223131954.6570-1-niels.dossche@ugent.be Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv6/addrconf.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 6652d96329a0c..ec9b8de5dd88a 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -4998,6 +4998,7 @@ static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa, nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) goto error;
+ spin_lock_bh(&ifa->lock); if (!((ifa->flags&IFA_F_PERMANENT) && (ifa->prefered_lft == INFINITY_LIFE_TIME))) { preferred = ifa->prefered_lft; @@ -5019,6 +5020,7 @@ static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa, preferred = INFINITY_LIFE_TIME; valid = INFINITY_LIFE_TIME; } + spin_unlock_bh(&ifa->lock);
if (!ipv6_addr_any(&ifa->peer_addr)) { if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||