* [PATCH] ip6_gre: simplify gre header parsing in ip6gre_err @ 2018-09-10 8:25 Haishuang Yan 2018-09-10 15:36 ` Jiri Benc 0 siblings, 1 reply; 4+ messages in thread From: Haishuang Yan @ 2018-09-10 8:25 UTC (permalink / raw) To: David S. Miller, Alexey Kuznetsov; +Cc: netdev, linux-kernel, Haishuang Yan Same as ip_gre, use gre_parse_header to parse gre header in gre error handler code. Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> --- net/ipv6/ip6_gre.c | 29 +++++++---------------------- 1 file changed, 7 insertions(+), 22 deletions(-) diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index 18a3794..505d891 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -427,35 +427,20 @@ static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt, u8 type, u8 code, int offset, __be32 info) { struct net *net = dev_net(skb->dev); - const struct gre_base_hdr *greh; const struct ipv6hdr *ipv6h; - int grehlen = sizeof(*greh); + struct tnl_ptk_info tpi; + bool csum_err = false; struct ip6_tnl *t; - int key_off = 0; - __be16 flags; - __be32 key; - if (!pskb_may_pull(skb, offset + grehlen)) - return; - greh = (const struct gre_base_hdr *)(skb->data + offset); - flags = greh->flags; - if (flags & (GRE_VERSION | GRE_ROUTING)) - return; - if (flags & GRE_CSUM) - grehlen += 4; - if (flags & GRE_KEY) { - key_off = grehlen + offset; - grehlen += 4; + if (gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), + offset) < 0) { + if (!csum_err) /* ignore csum errors. */ + return; } - if (!pskb_may_pull(skb, offset + grehlen)) - return; ipv6h = (const struct ipv6hdr *)skb->data; - greh = (const struct gre_base_hdr *)(skb->data + offset); - key = key_off ? *(__be32 *)(skb->data + key_off) : 0; - t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, - key, greh->protocol); + tpi.key, tpi.proto); if (!t) return; -- 1.8.3.1 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] ip6_gre: simplify gre header parsing in ip6gre_err 2018-09-10 8:25 [PATCH] ip6_gre: simplify gre header parsing in ip6gre_err Haishuang Yan @ 2018-09-10 15:36 ` Jiri Benc 2018-09-11 2:19 ` Haishuang Yan 0 siblings, 1 reply; 4+ messages in thread From: Jiri Benc @ 2018-09-10 15:36 UTC (permalink / raw) To: Haishuang Yan; +Cc: David S. Miller, Alexey Kuznetsov, netdev, linux-kernel On Mon, 10 Sep 2018 16:25:09 +0800, Haishuang Yan wrote: > + if (gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), > + offset) < 0) { > + if (!csum_err) /* ignore csum errors. */ > + return; > } gre_parse_header stops parsing when csum_err is encountered. Which means tpi.key is undefined... > > - if (!pskb_may_pull(skb, offset + grehlen)) > - return; > ipv6h = (const struct ipv6hdr *)skb->data; > - greh = (const struct gre_base_hdr *)(skb->data + offset); > - key = key_off ? *(__be32 *)(skb->data + key_off) : 0; > - > t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, > - key, greh->protocol); > + tpi.key, tpi.proto); ...and can't be used here. Jiri ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] ip6_gre: simplify gre header parsing in ip6gre_err 2018-09-10 15:36 ` Jiri Benc @ 2018-09-11 2:19 ` Haishuang Yan 2018-09-11 6:47 ` Jiri Benc 0 siblings, 1 reply; 4+ messages in thread From: Haishuang Yan @ 2018-09-11 2:19 UTC (permalink / raw) To: Jiri Benc; +Cc: David S. Miller, Alexey Kuznetsov, netdev, linux-kernel > On 2018年9月10日, at 下午11:36, Jiri Benc <jbenc@redhat.com> wrote: > > On Mon, 10 Sep 2018 16:25:09 +0800, Haishuang Yan wrote: >> + if (gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IPV6), >> + offset) < 0) { >> + if (!csum_err) /* ignore csum errors. */ >> + return; >> } > > gre_parse_header stops parsing when csum_err is encountered. Which > means tpi.key is undefined... > >> >> - if (!pskb_may_pull(skb, offset + grehlen)) >> - return; >> ipv6h = (const struct ipv6hdr *)skb->data; >> - greh = (const struct gre_base_hdr *)(skb->data + offset); >> - key = key_off ? *(__be32 *)(skb->data + key_off) : 0; >> - >> t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, >> - key, greh->protocol); >> + tpi.key, tpi.proto); > > ...and can't be used here. > > Jiri > You are right. Thanks for reviewing. So the same problem also arise in ipgre_err code: 187 iph = (const struct iphdr *)(icmp_hdr(skb) + 1); 188 t = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags, 189 iph->daddr, iph->saddr, tpi->key); Since csum_err may not be used outside, how about refactoring gre_parse_header function like this: --- a/net/ipv4/gre_demux.c +++ b/net/ipv4/gre_demux.c @@ -86,7 +86,7 @@ int gre_parse_header(struct sk_buff *skb, struct tnl_ptk_info *tpi, options = (__be32 *)(greh + 1); if (greh->flags & GRE_CSUM) { - if (skb_checksum_simple_validate(skb)) { + if (csum_err && skb_checksum_simple_validate(skb)) { *csum_err = true; return -EINVAL; } And in gre_err function, we can call gre_parse_header(skb, &tpi, NULL, **) like this: --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -234,11 +234,9 @@ static void gre_err(struct sk_buff *skb, u32 info) struct tnl_ptk_info tpi; bool csum_err = false; - if (gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), - iph->ihl * 4) < 0) { - if (!csum_err) /* ignore csum errors. */ + if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IP), + iph->ihl * 4) < 0) return; - } ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] ip6_gre: simplify gre header parsing in ip6gre_err 2018-09-11 2:19 ` Haishuang Yan @ 2018-09-11 6:47 ` Jiri Benc 0 siblings, 0 replies; 4+ messages in thread From: Jiri Benc @ 2018-09-11 6:47 UTC (permalink / raw) To: Haishuang Yan; +Cc: David S. Miller, Alexey Kuznetsov, netdev, linux-kernel On Tue, 11 Sep 2018 10:19:31 +0800, Haishuang Yan wrote: > Since csum_err may not be used outside, how about refactoring gre_parse_header function like this: > > --- a/net/ipv4/gre_demux.c > +++ b/net/ipv4/gre_demux.c > @@ -86,7 +86,7 @@ int gre_parse_header(struct sk_buff *skb, struct tnl_ptk_info *tpi, > > options = (__be32 *)(greh + 1); > if (greh->flags & GRE_CSUM) { > - if (skb_checksum_simple_validate(skb)) { > + if (csum_err && skb_checksum_simple_validate(skb)) { Something like this, yes. Thanks! Jiri ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2018-09-11 6:47 UTC | newest] Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2018-09-10 8:25 [PATCH] ip6_gre: simplify gre header parsing in ip6gre_err Haishuang Yan 2018-09-10 15:36 ` Jiri Benc 2018-09-11 2:19 ` Haishuang Yan 2018-09-11 6:47 ` Jiri Benc
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