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| author | Eric Dumazet <edumazet@google.com> | 2016-06-15 16:24:00 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-06-16 08:15:21 +0300 |
| commit | e582615ad33dbd39623084a02e95567b116e1eea (patch) | |
| tree | 16f807a602e42f6918f9991b0725bc6e26847025 /net/ipv4 | |
| parent | daddef76c3deaaa7922f9d7b18edbf0a061215c3 (diff) | |
| download | linux-e582615ad33dbd39623084a02e95567b116e1eea.tar.xz | |
gre: fix error handler
1) gre_parse_header() can be called from gre_err()
At this point transport header points to ICMP header, not the inner
header.
2) We can not really change transport header as ipgre_err() will later
assume transport header still points to ICMP header (using icmp_hdr())
3) pskb_may_pull() logic in gre_parse_header() really works
if we are interested at zone pointed by skb->data
4) As Jiri explained in commit b7f8fe251e46 ("gre: do not pull header in
ICMP error processing") we should not pull headers in error handler.
So this fix :
A) changes gre_parse_header() to use skb->data instead of
skb_transport_header()
B) Adds a nhs parameter to gre_parse_header() so that we can skip the
not pulled IP header from error path.
This offset is 0 for normal receive path.
C) remove obsolete IPV6 includes
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/gre_demux.c | 10 | ||||
| -rw-r--r-- | net/ipv4/ip_gre.c | 12 |
2 files changed, 9 insertions, 13 deletions
diff --git a/net/ipv4/gre_demux.c b/net/ipv4/gre_demux.c index 4c39f4fd332a..de1d119a4497 100644 --- a/net/ipv4/gre_demux.c +++ b/net/ipv4/gre_demux.c @@ -62,26 +62,26 @@ EXPORT_SYMBOL_GPL(gre_del_protocol); /* Fills in tpi and returns header length to be pulled. */ int gre_parse_header(struct sk_buff *skb, struct tnl_ptk_info *tpi, - bool *csum_err, __be16 proto) + bool *csum_err, __be16 proto, int nhs) { const struct gre_base_hdr *greh; __be32 *options; int hdr_len; - if (unlikely(!pskb_may_pull(skb, sizeof(struct gre_base_hdr)))) + if (unlikely(!pskb_may_pull(skb, nhs + sizeof(struct gre_base_hdr)))) return -EINVAL; - greh = (struct gre_base_hdr *)skb_transport_header(skb); + greh = (struct gre_base_hdr *)(skb->data + nhs); if (unlikely(greh->flags & (GRE_VERSION | GRE_ROUTING))) return -EINVAL; tpi->flags = gre_flags_to_tnl_flags(greh->flags); hdr_len = gre_calc_hlen(tpi->flags); - if (!pskb_may_pull(skb, hdr_len)) + if (!pskb_may_pull(skb, nhs + hdr_len)) return -EINVAL; - greh = (struct gre_base_hdr *)skb_transport_header(skb); + greh = (struct gre_base_hdr *)(skb->data + nhs); tpi->proto = greh->protocol; options = (__be32 *)(greh + 1); diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 07c5cf1838d8..1d000af7f561 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -49,12 +49,6 @@ #include <net/gre.h> #include <net/dst_metadata.h> -#if IS_ENABLED(CONFIG_IPV6) -#include <net/ipv6.h> -#include <net/ip6_fib.h> -#include <net/ip6_route.h> -#endif - /* Problems & solutions -------------------- @@ -217,12 +211,14 @@ static void gre_err(struct sk_buff *skb, u32 info) * by themselves??? */ + const struct iphdr *iph = (struct iphdr *)skb->data; const int type = icmp_hdr(skb)->type; const int code = icmp_hdr(skb)->code; struct tnl_ptk_info tpi; bool csum_err = false; - if (gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP)) < 0) { + if (gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), + iph->ihl * 4) < 0) { if (!csum_err) /* ignore csum errors. */ return; } @@ -338,7 +334,7 @@ static int gre_rcv(struct sk_buff *skb) } #endif - hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP)); + hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), 0); if (hdr_len < 0) goto drop; |