From 2248b8145053eb2ae35ca4cf694b885a086719bb Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Wed, 29 Jan 2025 19:15:18 -0800 Subject: [PATCH] net: ipv6: fix dst refleaks in rpl, seg6 and ioam6 lwtunnels commit c71a192976ded2f2f416d03c4f595cdd4478b825 upstream. dst_cache_get() gives us a reference, we need to release it. Discovered by the ioam6.sh test, kmemleak was recently fixed to catch per-cpu memory leaks. Fixes: 985ec6f5e623 ("net: ipv6: rpl_iptunnel: mitigate 2-realloc issue") Fixes: 40475b63761a ("net: ipv6: seg6_iptunnel: mitigate 2-realloc issue") Fixes: dce525185bc9 ("net: ipv6: ioam6_iptunnel: mitigate 2-realloc issue") Reviewed-by: Justin Iurman Reviewed-by: Simon Horman Link: https://patch.msgid.link/20250130031519.2716843-1-kuba@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/ipv6/ioam6_iptunnel.c | 5 +++-- net/ipv6/rpl_iptunnel.c | 6 ++++-- net/ipv6/seg6_iptunnel.c | 6 ++++-- 3 files changed, 11 insertions(+), 6 deletions(-) diff --git a/net/ipv6/ioam6_iptunnel.c b/net/ipv6/ioam6_iptunnel.c index fb6cb540cd1bc..4215cebe7d85a 100644 --- a/net/ipv6/ioam6_iptunnel.c +++ b/net/ipv6/ioam6_iptunnel.c @@ -338,7 +338,7 @@ static int ioam6_do_encap(struct net *net, struct sk_buff *skb, static int ioam6_output(struct net *net, struct sock *sk, struct sk_buff *skb) { - struct dst_entry *dst = skb_dst(skb), *cache_dst; + struct dst_entry *dst = skb_dst(skb), *cache_dst = NULL; struct in6_addr orig_daddr; struct ioam6_lwt *ilwt; int err = -EINVAL; @@ -409,7 +409,6 @@ do_encap: cache_dst = ip6_route_output(net, NULL, &fl6); if (cache_dst->error) { err = cache_dst->error; - dst_release(cache_dst); goto drop; } @@ -431,8 +430,10 @@ do_encap: return dst_output(net, sk, skb); } out: + dst_release(cache_dst); return dst->lwtstate->orig_output(net, sk, skb); drop: + dst_release(cache_dst); kfree_skb(skb); return err; } diff --git a/net/ipv6/rpl_iptunnel.c b/net/ipv6/rpl_iptunnel.c index be084089ec783..0ac4283acdf20 100644 --- a/net/ipv6/rpl_iptunnel.c +++ b/net/ipv6/rpl_iptunnel.c @@ -232,7 +232,6 @@ static int rpl_output(struct net *net, struct sock *sk, struct sk_buff *skb) dst = ip6_route_output(net, NULL, &fl6); if (dst->error) { err = dst->error; - dst_release(dst); goto drop; } @@ -254,6 +253,7 @@ static int rpl_output(struct net *net, struct sock *sk, struct sk_buff *skb) return dst_output(net, sk, skb); drop: + dst_release(dst); kfree_skb(skb); return err; } @@ -272,8 +272,10 @@ static int rpl_input(struct sk_buff *skb) local_bh_enable(); err = rpl_do_srh(skb, rlwt, dst); - if (unlikely(err)) + if (unlikely(err)) { + dst_release(dst); goto drop; + } if (!dst) { ip6_route_input(skb); diff --git a/net/ipv6/seg6_iptunnel.c b/net/ipv6/seg6_iptunnel.c index 316dbc2694f2a..33833b2064c07 100644 --- a/net/ipv6/seg6_iptunnel.c +++ b/net/ipv6/seg6_iptunnel.c @@ -482,8 +482,10 @@ static int seg6_input_core(struct net *net, struct sock *sk, local_bh_enable(); err = seg6_do_srh(skb, dst); - if (unlikely(err)) + if (unlikely(err)) { + dst_release(dst); goto drop; + } if (!dst) { ip6_route_input(skb); @@ -571,7 +573,6 @@ static int seg6_output_core(struct net *net, struct sock *sk, dst = ip6_route_output(net, NULL, &fl6); if (dst->error) { err = dst->error; - dst_release(dst); goto drop; } @@ -596,6 +597,7 @@ static int seg6_output_core(struct net *net, struct sock *sk, return dst_output(net, sk, skb); drop: + dst_release(dst); kfree_skb(skb); return err; } -- 2.47.3