From 36268983e90316b37000a005642af42234dabb36 Mon Sep 17 00:00:00 2001 From: Guillaume Nault Date: Wed, 26 Jan 2022 16:38:52 +0100 Subject: Revert "ipv6: Honor all IPv6 PIO Valid Lifetime values" This reverts commit b75326c201242de9495ff98e5d5cff41d7fc0d9d. This commit breaks Linux compatibility with USGv6 tests. The RFC this commit was based on is actually an expired draft: no published RFC currently allows the new behaviour it introduced. Without full IETF endorsement, the flash renumbering scenario this patch was supposed to enable is never going to work, as other IPv6 equipements on the same LAN will keep the 2 hours limit. Fixes: b75326c20124 ("ipv6: Honor all IPv6 PIO Valid Lifetime values") Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller --- include/net/addrconf.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/net') diff --git a/include/net/addrconf.h b/include/net/addrconf.h index 78ea3e332688..e7ce719838b5 100644 --- a/include/net/addrconf.h +++ b/include/net/addrconf.h @@ -6,6 +6,8 @@ #define RTR_SOLICITATION_INTERVAL (4*HZ) #define RTR_SOLICITATION_MAX_INTERVAL (3600*HZ) /* 1 hour */ +#define MIN_VALID_LIFETIME (2*3600) /* 2 hours */ + #define TEMP_VALID_LIFETIME (7*86400) #define TEMP_PREFERRED_LIFETIME (86400) #define REGEN_MAX_RETRY (3) -- cgit v1.2.3-59-g8ed1b From 23f57406b82de51809d5812afd96f210f8b627f3 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 26 Jan 2022 17:10:22 -0800 Subject: ipv4: avoid using shared IP generator for connected sockets ip_select_ident_segs() has been very conservative about using the connected socket private generator only for packets with IP_DF set, claiming it was needed for some VJ compression implementations. As mentioned in this referenced document, this can be abused. (Ref: Off-Path TCP Exploits of the Mixed IPID Assignment) Before switching to pure random IPID generation and possibly hurt some workloads, lets use the private inet socket generator. Not only this will remove one vulnerability, this will also improve performance of TCP flows using pmtudisc==IP_PMTUDISC_DONT Fixes: 73f156a6e8c1 ("inetpeer: get rid of ip_id_count") Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Reported-by: Ray Che Cc: Willy Tarreau Signed-off-by: Jakub Kicinski --- include/net/ip.h | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) (limited to 'include/net') diff --git a/include/net/ip.h b/include/net/ip.h index 81e23a102a0d..b51bae43b0dd 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -525,19 +525,18 @@ static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb, { struct iphdr *iph = ip_hdr(skb); + /* We had many attacks based on IPID, use the private + * generator as much as we can. + */ + if (sk && inet_sk(sk)->inet_daddr) { + iph->id = htons(inet_sk(sk)->inet_id); + inet_sk(sk)->inet_id += segs; + return; + } if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) { - /* This is only to work around buggy Windows95/2000 - * VJ compression implementations. If the ID field - * does not change, they drop every other packet in - * a TCP stream using header compression. - */ - if (sk && inet_sk(sk)->inet_daddr) { - iph->id = htons(inet_sk(sk)->inet_id); - inet_sk(sk)->inet_id += segs; - } else { - iph->id = 0; - } + iph->id = 0; } else { + /* Unfortunately we need the big hammer to get a suitable IPID */ __ip_select_ident(net, iph, segs); } } -- cgit v1.2.3-59-g8ed1b From 3c42b2019863b327caa233072c50739d4144dd16 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 26 Jan 2022 17:34:04 -0800 Subject: ipv4: remove sparse error in ip_neigh_gw4() ./include/net/route.h:373:48: warning: incorrect type in argument 2 (different base types) ./include/net/route.h:373:48: expected unsigned int [usertype] key ./include/net/route.h:373:48: got restricted __be32 [usertype] daddr Fixes: 5c9f7c1dfc2e ("ipv4: Add helpers for neigh lookup for nexthop") Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20220127013404.1279313-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski --- include/net/route.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/net') diff --git a/include/net/route.h b/include/net/route.h index 4c858dcf1aa8..25404fc2b483 100644 --- a/include/net/route.h +++ b/include/net/route.h @@ -370,7 +370,7 @@ static inline struct neighbour *ip_neigh_gw4(struct net_device *dev, { struct neighbour *neigh; - neigh = __ipv4_neigh_lookup_noref(dev, daddr); + neigh = __ipv4_neigh_lookup_noref(dev, (__force u32)daddr); if (unlikely(!neigh)) neigh = __neigh_create(&arp_tbl, &daddr, dev, false); -- cgit v1.2.3-59-g8ed1b