kernel/linux.git/net/ipv6, branch linux-5.9.y

net: ip6_gre: set dev->hard_header_len when using header_ops

2020-12-08T09:42:02+00:00

[ Upstream commit 832ba596494b2c9eac7760259eff2d8b7dcad0ee ] syzkaller managed to crash the kernel using an NBMA ip6gre interface. I could reproduce it creating an NBMA ip6gre interface and forwarding traffic to it: skbuff: skb_under_panic: text:ffffffff8250e927 len:148 put:44 head:ffff8c03c7a33 ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:109! Call Trace: skb_push+0x10/0x10 ip6gre_header+0x47/0x1b0 neigh_connected_output+0xae/0xf0 ip6gre tunnel provides its own header_ops->create, and sets it conditionally when initializing the tunnel in NBMA mode. When header_ops->create is used, dev->hard_header_len should reflect the length of the header created. Otherwise, when not used, dev->needed_headroom should be used. Fixes: eb95f52fc72d ("net: ipv6_gre: Fix GRO to work on IPv6 over GRE tap") Cc: Maria Pasechnik Signed-off-by: Antoine Tenart Link: https://lore.kernel.org/r/20201130161911.464106-1-atenart@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

ipv6: addrlabel: fix possible memory leak in ip6addrlbl_net_init

2020-12-08T09:41:59+00:00

[ Upstream commit e255e11e66da8281e337e4e352956e8a4999fca4 ] kmemleak report a memory leak as follows: unreferenced object 0xffff8880059c6a00 (size 64): comm "ip", pid 23696, jiffies 4296590183 (age 1755.384s) hex dump (first 32 bytes): 20 01 00 10 00 00 00 00 00 00 00 00 00 00 00 00 ............... 1c 00 00 00 00 00 00 00 00 00 00 00 07 00 00 00 ................ backtrace: [<00000000aa4e7a87>] ip6addrlbl_add+0x90/0xbb0 [<0000000070b8d7f1>] ip6addrlbl_net_init+0x109/0x170 [<000000006a9ca9d4>] ops_init+0xa8/0x3c0 [<000000002da57bf2>] setup_net+0x2de/0x7e0 [<000000004e52d573>] copy_net_ns+0x27d/0x530 [<00000000b07ae2b4>] create_new_namespaces+0x382/0xa30 [<000000003b76d36f>] unshare_nsproxy_namespaces+0xa1/0x1d0 [<0000000030653721>] ksys_unshare+0x3a4/0x780 [<0000000007e82e40>] __x64_sys_unshare+0x2d/0x40 [<0000000031a10c08>] do_syscall_64+0x33/0x40 [<0000000099df30e7>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 We should free all rules when we catch an error in ip6addrlbl_net_init(). otherwise a memory leak will occur. Fixes: 2a8cc6c89039 ("[IPV6] ADDRCONF: Support RFC3484 configurable address selection policy table.") Reported-by: Hulk Robot Signed-off-by: Wang Hai Link: https://lore.kernel.org/r/20201124071728.8385-1-wanghai38@huawei.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

ipv6: Fix error path to cancel the meseage

2020-11-24T12:38:46+00:00

[ Upstream commit ceb736e1d45c253f5e86b185ca9b497cdd43063f ] genlmsg_cancel() needs to be called in the error path of inet6_fill_ifmcaddr and inet6_fill_ifacaddr to cancel the message. Fixes: 6ecf4c37eb3e ("ipv6: enable IFA_TARGET_NETNSID for RTM_GETADDR") Reported-by: Hulk Robot Signed-off-by: Zhang Qilong Link: https://lore.kernel.org/r/20201112080950.1476302-1-zhangqilong3@huawei.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

Exempt multicast addresses from five-second neighbor lifetime

2020-11-24T12:38:46+00:00

[ Upstream commit 8cf8821e15cd553339a5b48ee555a0439c2b2742 ] Commit 58956317c8de ("neighbor: Improve garbage collection") guarantees neighbour table entries a five-second lifetime. Processes which make heavy use of multicast can fill the neighour table with multicast addresses in five seconds. At that point, neighbour entries can't be GC-ed because they aren't five seconds old yet, the kernel log starts to fill up with "neighbor table overflow!" messages, and sends start to fail. This patch allows multicast addresses to be thrown out before they've lived out their five seconds. This makes room for non-multicast addresses and makes messages to all addresses more reliable in these circumstances. Fixes: 58956317c8de ("neighbor: Improve garbage collection") Signed-off-by: Jeff Dike Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20201113015815.31397-1-jdike@akamai.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

ah6: fix error return code in ah6_input()

2020-11-24T12:38:46+00:00

[ Upstream commit a5ebcbdf34b65fcc07f38eaf2d60563b42619a59 ] Fix to return a negative error code from the error handling case instead of 0, as done elsewhere in this function. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Hulk Robot Signed-off-by: Zhang Changzhong Link: https://lore.kernel.org/r/1605581105-35295-1-git-send-email-zhangchangzhong@huawei.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

net: Update window_clamp if SOCK_RCVBUF is set

2020-11-18T18:22:31+00:00

[ Upstream commit 909172a149749242990a6e64cb55d55460d4e417 ] When net.ipv4.tcp_syncookies=1 and syn flood is happened, cookie_v4_check or cookie_v6_check tries to redo what tcp_v4_send_synack or tcp_v6_send_synack did, rsk_window_clamp will be changed if SOCK_RCVBUF is set, which will make rcv_wscale is different, the client still operates with initial window scale and can overshot granted window, the client use the initial scale but local server use new scale to advertise window value, and session work abnormally. Fixes: e88c64f0a425 ("tcp: allow effective reduction of TCP's rcv-buffer via setsockopt") Signed-off-by: Mao Wenan Signed-off-by: Eric Dumazet Link: https://lore.kernel.org/r/1604967391-123737-1-git-send-email-wenan.mao@linux.alibaba.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

net: udp: fix IP header access and skb lookup on Fast/frag0 UDP GRO

2020-11-18T18:22:31+00:00

[ Upstream commit 55e729889bb07d68ab071660ce3f5e7a7872ebe8 ] udp{4,6}_lib_lookup_skb() use ip{,v6}_hdr() to get IP header of the packet. While it's probably OK for non-frag0 paths, this helpers will also point to junk on Fast/frag0 GRO when all headers are located in frags. As a result, sk/skb lookup may fail or give wrong results. To support both GRO modes, skb_gro_network_header() might be used. To not modify original functions, add private versions of udp{4,6}_lib_lookup_skb() only to perform correct sk lookups on GRO. Present since the introduction of "application-level" UDP GRO in 4.7-rc1. Misc: replace totally unneeded ternaries with plain ifs. Fixes: a6024562ffd7 ("udp: Add GRO functions to UDP socket") Suggested-by: Willem de Bruijn Cc: Eric Dumazet Signed-off-by: Alexander Lobakin Acked-by: Willem de Bruijn Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

IPv6: Set SIT tunnel hard_header_len to zero

2020-11-18T18:22:31+00:00

[ Upstream commit 8ef9ba4d666614497a057d09b0a6eafc1e34eadf ] Due to the legacy usage of hard_header_len for SIT tunnels while already using infrastructure from net/ipv4/ip_tunnel.c the calculation of the path MTU in tnl_update_pmtu is incorrect. This leads to unnecessary creation of MTU exceptions for any flow going over a SIT tunnel. As SIT tunnels do not have a header themsevles other than their transport (L3, L2) headers we're leaving hard_header_len set to zero as tnl_update_pmtu is already taking care of the transport headers sizes. This will also help avoiding unnecessary IPv6 GC runs and spinlock contention seen when using SIT tunnels and for more than net.ipv6.route.gc_thresh flows. Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.") Signed-off-by: Oliver Herms Acked-by: Willem de Bruijn Link: https://lore.kernel.org/r/20201103104133.GA1573211@tws Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

netfilter: use actual socket sk rather than skb sk when routing harder

2020-11-18T18:22:02+00:00

[ Upstream commit 46d6c5ae953cc0be38efd0e469284df7c4328cf8 ] If netfilter changes the packet mark when mangling, the packet is rerouted using the route_me_harder set of functions. Prior to this commit, there's one big difference between route_me_harder and the ordinary initial routing functions, described in the comment above __ip_queue_xmit(): /* Note: skb->sk can be different from sk, in case of tunnels */ int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, That function goes on to correctly make use of sk->sk_bound_dev_if, rather than skb->sk->sk_bound_dev_if. And indeed the comment is true: a tunnel will receive a packet in ndo_start_xmit with an initial skb->sk. It will make some transformations to that packet, and then it will send the encapsulated packet out of a *new* socket. That new socket will basically always have a different sk_bound_dev_if (otherwise there'd be a routing loop). So for the purposes of routing the encapsulated packet, the routing information as it pertains to the socket should come from that socket's sk, rather than the packet's original skb->sk. For that reason __ip_queue_xmit() and related functions all do the right thing. One might argue that all tunnels should just call skb_orphan(skb) before transmitting the encapsulated packet into the new socket. But tunnels do *not* do this -- and this is wisely avoided in skb_scrub_packet() too -- because features like TSQ rely on skb->destructor() being called when that buffer space is truely available again. Calling skb_orphan(skb) too early would result in buffers filling up unnecessarily and accounting info being all wrong. Instead, additional routing must take into account the new sk, just as __ip_queue_xmit() notes. So, this commit addresses the problem by fishing the correct sk out of state->sk -- it's already set properly in the call to nf_hook() in __ip_local_out(), which receives the sk as part of its normal functionality. So we make sure to plumb state->sk through the various route_me_harder functions, and then make correct use of it following the example of __ip_queue_xmit(). Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Jason A. Donenfeld Reviewed-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin

xfrm: interface: fix the priorities for ipip and ipv6 tunnels

2020-11-18T18:21:59+00:00

[ Upstream commit 7fe94612dd4cfcd35fe0ec87745fb31ad2be71f8 ] As Nicolas noticed in his case, when xfrm_interface module is installed the standard IP tunnels will break in receiving packets. This is caused by the IP tunnel handlers with a higher priority in xfrm interface processing incoming packets by xfrm_input(), which would drop the packets and return 0 instead when anything wrong happens. Rather than changing xfrm_input(), this patch is to adjust the priority for the IP tunnel handlers in xfrm interface, so that the packets would go to xfrmi's later than the others', as the others' would not drop the packets when the handlers couldn't process them. Note that IPCOMP also defines its own IPIP tunnel handler and it calls xfrm_input() as well, so we must make its priority lower than xfrmi's, which means having xfrmi loaded would still break IPCOMP. We may seek another way to fix it in xfrm_input() in the future. Reported-by: Nicolas Dichtel Tested-by: Nicolas Dichtel Fixes: da9bbf0598c9 ("xfrm: interface: support IPIP and IPIP6 tunnels processing with .cb_handler") FIxes: d7b360c2869f ("xfrm: interface: support IP6IP6 and IP6IP tunnels processing with .cb_handler") Signed-off-by: Xin Long Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin