kernel/linux.git/net/ipv6/icmp.c, branch linux-4.16.y

ipv6: mark expected switch fall-throughs

2017-10-18T13:13:08+00:00

In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. Notice that in some cases I placed the "fall through" comment on its own line, which is what GCC is expecting to find. Signed-off-by: Gustavo A. R. Silva Signed-off-by: David S. Miller

net/ipv6: Convert icmpv6_push_pending_frames to void

2017-10-06T16:52:31+00:00

commit cc71b7b07119 ("net/ipv6: remove unused err variable on icmpv6_push_pending_frames") exposed icmpv6_push_pending_frames return value not being used. Remove now unnecessary int err declarations and uses. Miscellanea: o Remove unnecessary goto and out: labels o Realign arguments Signed-off-by: Joe Perches Signed-off-by: David S. Miller

net/ipv6: remove unused err variable on icmpv6_push_pending_frames

2017-10-06T04:56:26+00:00

int err is unused by icmpv6_push_pending_frames(), this patch returns removes the variable and returns the function with 0. git bisect shows this variable has been around since linux has been in git in commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2. This was found by running make coccicheck M=net/ipv6/ on linus' tree on commit 77ede3a014a32746002f7889211f0cecf4803163 (current HEAD as of this patch). Signed-off-by: Tim Hansen Signed-off-by: David S. Miller

ipv6: Use rt6i_idev index for echo replies to a local address

2017-08-29T22:32:25+00:00

Tariq repored local pings to linklocal address is failing: $ ifconfig ens8 ens8: flags=4163 mtu 1500 inet 11.141.16.6 netmask 255.255.0.0 broadcast 11.141.255.255 inet6 fe80::7efe:90ff:fecb:7502 prefixlen 64 scopeid 0x20 ether 7c:fe:90:cb:75:02 txqueuelen 1000 (Ethernet) RX packets 12 bytes 1164 (1.1 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 30 bytes 2484 (2.4 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 $ /bin/ping6 -c 3 fe80::7efe:90ff:fecb:7502%ens8 PING fe80::7efe:90ff:fecb:7502%ens8(fe80::7efe:90ff:fecb:7502) 56 data bytes Signed-off-by: David S. Miller

ipv6: Compute multipath hash for ICMP errors from offending packet

2017-08-25T01:21:17+00:00

When forwarding or sending out an ICMPv6 error, look at the embedded packet that triggered the error and compute a flow hash over its headers. This let's us route the ICMP error together with the flow it belongs to when multipath (ECMP) routing is in use, which in turn makes Path MTU Discovery work in ECMP load-balanced or anycast setups (RFC 7690). Granted, end-hosts behind the ECMP router (aka servers) need to reflect the IPv6 Flow Label for PMTUD to work. The code is organized to be in parallel with ipv4 stack: ip_multipath_l3_keys -> ip6_multipath_l3_keys fib_multipath_hash -> rt6_multipath_hash Signed-off-by: Jakub Sitnicki Signed-off-by: David S. Miller

net: ipv6: put host and anycast routes on device with address

2017-08-21T17:40:17+00:00

One nagging difference between ipv4 and ipv6 is host routes for ipv6 addresses are installed using the loopback device or VRF / L3 Master device. e.g., 2001:db8:1::/120 dev veth0 proto kernel metric 256 pref medium local 2001:db8:1::1 dev lo table local proto kernel metric 0 pref medium Using the loopback device is convenient -- necessary for local tx, but has some nasty side effects, most notably setting the 'lo' device down causes all host routes for all local IPv6 address to be removed from the FIB and completely breaks IPv6 networking across all interfaces. This patch puts FIB entries for IPv6 routes against the device. This simplifies the routes in the FIB, for example by making dst->dev and rt6i_idev->dev the same (a future patch can look at removing the device reference taken for rt6i_idev for FIB entries). When copies are made on FIB lookups, the cloned route has dst->dev set to loopback (or the L3 master device). This is needed for the local Tx of packets to local addresses. With fib entries allocated against the real network device, the addrconf code that reinserts host routes on admin up of 'lo' is no longer needed. Signed-off-by: David Ahern Signed-off-by: David S. Miller

net: don't global ICMP rate limit packets originating from loopback

2017-06-14T19:33:58+00:00

Florian Weimer seems to have a glibc test-case which requires that loopback interfaces does not get ICMP ratelimited. This was broken by commit c0303efeab73 ("net: reduce cycles spend on ICMP replies that gets rate limited"). An ICMP response will usually be routed back-out the same incoming interface. Thus, take advantage of this and skip global ICMP ratelimit when the incoming device is loopback. In the unlikely event that the outgoing it not loopback, due to strange routing policy rules, ICMP rate limiting still works via peer ratelimiting via icmpv4_xrlim_allow(). Thus, we should still comply with RFC1812 (section 4.3.2.8 "Rate Limiting"). This seems to fix the reproducer given by Florian. While still avoiding to perform expensive and unneeded outgoing route lookup for rate limited packets (in the non-loopback case). Fixes: c0303efeab73 ("net: reduce cycles spend on ICMP replies that gets rate limited") Reported-by: Florian Weimer Reported-by: "H.J. Lu" Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller

net: for rate-limited ICMP replies save one atomic operation

2017-01-09T20:49:12+00:00

It is possible to avoid the atomic operation in icmp{v6,}_xmit_lock, by checking the sysctl_icmp_msgs_per_sec ratelimit before these calls, as pointed out by Eric Dumazet, but the BH disabled state must be correct. The icmp_global_allow() call states it must be called with BH disabled. This protection was given by the calls icmp_xmit_lock and icmpv6_xmit_lock. Thus, split out local_bh_disable/enable from these functions and maintain it explicitly at callers. Suggested-by: Eric Dumazet Signed-off-by: Jesper Dangaard Brouer Acked-by: Eric Dumazet Signed-off-by: David S. Miller

net: reduce cycles spend on ICMP replies that gets rate limited

2017-01-09T20:49:12+00:00

This patch split the global and per (inet)peer ICMP-reply limiter code, and moves the global limit check to earlier in the packet processing path. Thus, avoid spending cycles on ICMP replies that gets limited/suppressed anyhow. The global ICMP rate limiter icmp_global_allow() is a good solution, it just happens too late in the process. The kernel goes through the full route lookup (return path) for the ICMP message, before taking the rate limit decision of not sending the ICMP reply. Details: The kernels global rate limiter for ICMP messages got added in commit 4cdf507d5452 ("icmp: add a global rate limitation"). It is a token bucket limiter with a global lock. It brilliantly avoids locking congestion by only updating when 20ms (HZ/50) were elapsed. It can then avoids taking lock when credit is exhausted (when under pressure) and time constraint for refill is not yet meet. Signed-off-by: Jesper Dangaard Brouer Acked-by: Eric Dumazet Signed-off-by: David S. Miller

Replace with globally

2016-12-24T19:46:01+00:00

This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*' sed -i -e "s!$PATT!#include !" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro Signed-off-by: Linus Torvalds