linux/net/ipv6
Maxime Bizon 418a73074d net: dst: fix missing initialization of rt_uncached
xfrm_alloc_dst() followed by xfrm4_dst_destroy(), without a
xfrm4_fill_dst() call in between, causes the following BUG:

 BUG: spinlock bad magic on CPU#0, fbxhostapd/732
  lock: 0x890b7668, .magic: 890b7668, .owner: <none>/-1, .owner_cpu: 0
 CPU: 0 PID: 732 Comm: fbxhostapd Not tainted 6.3.0-rc6-next-20230414-00613-ge8de66369925-dirty #9
 Hardware name: Marvell Kirkwood (Flattened Device Tree)
  unwind_backtrace from show_stack+0x10/0x14
  show_stack from dump_stack_lvl+0x28/0x30
  dump_stack_lvl from do_raw_spin_lock+0x20/0x80
  do_raw_spin_lock from rt_del_uncached_list+0x30/0x64
  rt_del_uncached_list from xfrm4_dst_destroy+0x3c/0xbc
  xfrm4_dst_destroy from dst_destroy+0x5c/0xb0
  dst_destroy from rcu_process_callbacks+0xc4/0xec
  rcu_process_callbacks from __do_softirq+0xb4/0x22c
  __do_softirq from call_with_stack+0x1c/0x24
  call_with_stack from do_softirq+0x60/0x6c
  do_softirq from __local_bh_enable_ip+0xa0/0xcc

Patch "net: dst: Prevent false sharing vs. dst_entry:: __refcnt" moved
rt_uncached and rt_uncached_list fields from rtable struct to dst
struct, so they are more zeroed by memset_after(xdst, 0, u.dst) in
xfrm_alloc_dst().

Note that rt_uncached (list_head) was never properly initialized at
alloc time, but xfrm[46]_dst_destroy() is written in such a way that
it was not an issue thanks to the memset:

	if (xdst->u.rt.dst.rt_uncached_list)
		rt_del_uncached_list(&xdst->u.rt);

The route code does it the other way around: rt_uncached_list is
assumed to be valid IIF rt_uncached list_head is not empty:

void rt_del_uncached_list(struct rtable *rt)
{
        if (!list_empty(&rt->dst.rt_uncached)) {
                struct uncached_list *ul = rt->dst.rt_uncached_list;

                spin_lock_bh(&ul->lock);
                list_del_init(&rt->dst.rt_uncached);
                spin_unlock_bh(&ul->lock);
        }
}

This patch adds mandatory rt_uncached list_head initialization in
generic dst_init(), and adapt xfrm[46]_dst_destroy logic to match the
rest of the code.

Fixes: d288a162dd ("net: dst: Prevent false sharing vs. dst_entry:: __refcnt")
Reported-by: kernel test robot <oliver.sang@intel.com>
Link: https://lore.kernel.org/oe-lkp/202304162125.18b7bcdd-oliver.sang@intel.com
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
CC: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Link: https://lore.kernel.org/r/20230420182508.2417582-1-mbizon@freebox.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-21 20:26:56 -07:00
..
ila ila: do not generate empty messages in ila_xlat_nl_cmd_get_mapping() 2023-03-01 08:48:46 +00:00
netfilter xtables: move icmp/icmpv6 logic to xt_tcpudp 2023-03-22 21:48:59 +01:00
addrconf_core.c net: rename reference+tracking helpers 2022-06-09 21:52:55 -07:00
addrconf.c ipv6: prevent router_solicitations for team port 2023-03-24 08:57:06 +00:00
addrlabel.c ipv6: addrlabel: fix infoleak when sending struct ifaddrlblmsg to network 2022-11-07 12:26:15 +00:00
af_inet6.c ipv6: add icmpv6_error_anycast_as_unicast for ICMPv6 2023-04-20 20:07:50 -07:00
ah6.c net: ipv6: Remove completion function scaffolding 2023-02-13 18:35:15 +08:00
anycast.c
calipso.c
datagram.c ipv6: Fix datagram socket connection with DSCP. 2023-02-09 22:49:04 -08:00
esp6_offload.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2022-11-29 20:50:51 -08:00
esp6.c net: ipv6: Remove completion function scaffolding 2023-02-13 18:35:15 +08:00
exthdrs_core.c
exthdrs_offload.c
exthdrs.c net: ipv6: add skb drop reasons to TLV parse 2022-04-13 13:09:57 +01:00
fib6_notifier.c
fib6_rules.c ipv6: change fib6_rules_net_exit() to batch mode 2022-02-08 20:41:34 -08:00
fou6.c
icmp.c ipv6: add icmpv6_error_anycast_as_unicast for ICMPv6 2023-04-20 20:07:50 -07:00
inet6_connection_sock.c net: annotate lockless accesses to sk->sk_err_soft 2023-03-17 08:25:05 +00:00
inet6_hashtables.c tcp: Access &tcp_hashinfo via net. 2022-09-20 10:21:49 -07:00
ioam6_iptunnel.c ipv6: ioam: Insertion frequency in lwtunnel output 2022-02-04 20:24:45 -08:00
ioam6.c genetlink: start to validate reserved header bytes 2022-08-29 12:47:15 +01:00
ip6_checksum.c
ip6_fib.c ipv6: fib6_new_sernum() optimization 2022-11-16 12:42:00 +00:00
ip6_flowlabel.c ipv6: flowlabel: do not disable BH where not needed 2023-03-21 21:32:18 -07:00
ip6_gre.c erspan: do not use skb_mac_header() in ndo_start_xmit() 2023-03-21 21:16:26 -07:00
ip6_icmp.c
ip6_input.c netfilter: keep conntrack reference until IPsecv6 policy checks are done 2023-03-22 21:50:23 +01:00
ip6_offload.c IPv6/GRO: generic helper to remove temporary HBH/jumbo header in driver 2022-12-12 15:41:44 -08:00
ip6_offload.h
ip6_output.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-04-06 12:01:20 -07:00
ip6_tunnel.c net: tunnels: annotate lockless accesses to dev->needed_headroom 2023-03-15 00:04:04 -07:00
ip6_udp_tunnel.c
ip6_vti.c ipv6: tunnels: use DEV_STATS_INC() 2022-11-16 12:48:44 +00:00
ip6mr.c treewide: Convert del_timer*() to timer_shutdown*() 2022-12-25 13:38:09 -08:00
ipcomp6.c xfrm: ipcomp: add extack to ipcomp{4,6}_init_state 2022-09-29 07:18:00 +02:00
ipv6_sockglue.c net/ipv6: Initialise msg_control_is_user 2023-04-14 11:09:27 +01:00
Kconfig crypto: lib - make the sha1 library optional 2022-07-15 16:43:59 +08:00
Makefile net: ipv6: use ipv6-y directly instead of ipv6-objs 2021-09-28 13:13:40 +01:00
mcast_snoop.c net: bridge: mcast: fix broken length + header check for MRDv6 Adv. 2021-04-27 14:02:06 -07:00
mcast.c ipv6: constify inet6_mc_check() 2023-03-17 08:56:37 +00:00
mip6.c xfrm: mip6: add extack to mip6_destopt_init_state, mip6_rthdr_init_state 2022-09-29 07:18:01 +02:00
ndisc.c neighbour: annotate lockless accesses to n->nud_state 2023-03-15 00:37:32 -07:00
netfilter.c netfilter: Use l3mdev flow key when re-routing mangled packets 2022-05-16 13:03:29 +02:00
output_core.c treewide: use get_random_u32_{above,below}() instead of manual loop 2022-11-18 02:15:22 +01:00
ping.c inet: preserve const qualifier in inet_sk() 2023-03-17 08:56:37 +00:00
proc.c icmp: Add counters for rate limits 2023-01-26 10:52:18 +01:00
protocol.c
raw.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-04-06 12:01:20 -07:00
reassembly.c net: dropreason: add SKB_DROP_REASON_DUP_FRAG 2022-10-31 20:14:26 -07:00
route.c net: dst: fix missing initialization of rt_uncached 2023-04-21 20:26:56 -07:00
rpl_iptunnel.c net: ipv6: rpl_iptunnel: Replace 0-length arrays with flexible arrays 2023-01-06 19:28:01 -08:00
rpl.c net: rpl: fix rpl header size calculation 2023-04-19 09:04:16 +01:00
seg6_hmac.c net: ipv6: unexport __init-annotated seg6_hmac_net_init() 2022-06-28 21:23:30 -07:00
seg6_iptunnel.c seg6: add support for SRv6 H.L2Encaps.Red behavior 2022-07-29 12:14:03 +01:00
seg6_local.c seg6: add PSP flavor support for SRv6 End behavior 2023-02-16 13:18:06 +01:00
seg6.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-09-08 18:38:30 +02:00
sit.c ipip,ip_tunnel,sit: Add FOU support for externally controlled ipip devices 2023-04-12 16:40:39 -07:00
syncookies.c tcp: Fix data-races around sysctl_tcp_syncookies. 2022-07-18 12:21:54 +01:00
sysctl_net_ipv6.c net: sysctl: introduce sysctl SYSCTL_THREE 2022-05-03 10:15:06 +02:00
tcp_ipv6.c netfilter: keep conntrack reference until IPsecv6 policy checks are done 2023-03-22 21:50:23 +01:00
tcpv6_offload.c net: move gro definitions to include/net/gro.h 2021-11-16 13:16:54 +00:00
tunnel6.c
udp_impl.h tcp/udp: Call inet6_destroy_sock() in IPv6 sk->sk_destruct(). 2022-10-12 17:50:37 -07:00
udp_offload.c udp: allow header check for dodgy GSO_UDP_L4 packets. 2022-12-12 09:29:56 +00:00
udp.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-04-13 16:04:28 -07:00
udplite.c tcp/udp: Call inet6_destroy_sock() in IPv6 sk->sk_destruct(). 2022-10-12 17:50:37 -07:00
xfrm6_input.c
xfrm6_output.c xfrm: fix tunnel model fragmentation behavior 2022-03-01 12:08:40 +01:00
xfrm6_policy.c net: dst: fix missing initialization of rt_uncached 2023-04-21 20:26:56 -07:00
xfrm6_protocol.c
xfrm6_state.c
xfrm6_tunnel.c xfrm: tunnel: add extack to ipip_init_state, xfrm6_tunnel_init_state 2022-09-29 07:18:00 +02:00