Eric Dumazet 3b52569152 ipv6: fix suspicious RCU usage in rt6_dump_route() ... syzbot reminded us that rt6_nh_dump_exceptions() needs to be called with rcu_read_lock() net/ipv6/route.c:1593 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 2 locks held by syz-executor609/8966: #0: 00000000b7dbe288 (rtnl_mutex){+.+.}, at: netlink_dump+0xe7/0xfb0 net/netlink/af_netlink.c:2199 #1: 00000000f2d87c21 (&(&tb->tb6_lock)->rlock){+...}, at: spin_lock_bh include/linux/spinlock.h:343 [inline] #1: 00000000f2d87c21 (&(&tb->tb6_lock)->rlock){+...}, at: fib6_dump_table.isra.0+0x37e/0x570 net/ipv6/ip6_fib.c:533 stack backtrace: CPU: 0 PID: 8966 Comm: syz-executor609 Not tainted 5.2.0-rc5+ #43 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5250 fib6_nh_get_excptn_bucket+0x18e/0x1b0 net/ipv6/route.c:1593 rt6_nh_dump_exceptions+0x45/0x4d0 net/ipv6/route.c:5541 rt6_dump_route+0x904/0xc50 net/ipv6/route.c:5640 fib6_dump_node+0x168/0x280 net/ipv6/ip6_fib.c:467 fib6_walk_continue+0x4a9/0x8e0 net/ipv6/ip6_fib.c:1986 fib6_walk+0x9d/0x100 net/ipv6/ip6_fib.c:2034 fib6_dump_table.isra.0+0x38a/0x570 net/ipv6/ip6_fib.c:534 inet6_dump_fib+0x93c/0xb00 net/ipv6/ip6_fib.c:624 rtnl_dump_all+0x295/0x490 net/core/rtnetlink.c:3445 netlink_dump+0x558/0xfb0 net/netlink/af_netlink.c:2244 __netlink_dump_start+0x5b1/0x7d0 net/netlink/af_netlink.c:2352 netlink_dump_start include/linux/netlink.h:226 [inline] rtnetlink_rcv_msg+0x73d/0xb00 net/core/rtnetlink.c:5182 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5237 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:665 sock_write_iter+0x27c/0x3e0 net/socket.c:994 call_write_iter include/linux/fs.h:1872 [inline] new_sync_write+0x4d3/0x770 fs/read_write.c:483 __vfs_write+0xe1/0x110 fs/read_write.c:496 vfs_write+0x20c/0x580 fs/read_write.c:558 ksys_write+0x14f/0x290 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write fs/read_write.c:620 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:620 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4401b9 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffc8e134978 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401b9 RDX: 000000000000001c RSI: 0000000020000000 RDI: 00 Fixes: 1e47b4837f ("ipv6: Dump route exceptions if requested") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Stefano Brivio <sbrivio@redhat.com> Cc: David Ahern <dsahern@gmail.com> Reviewed-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2019-06-26 09:07:50 -07:00
..
ila
netfilter	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2019-06-25 01:32:59 +02:00
addrconf_core.c
addrconf.c
addrlabel.c
af_inet6.c
ah6.c
anycast.c
calipso.c
datagram.c
esp6_offload.c
esp6.c
exthdrs_core.c
exthdrs_offload.c
exthdrs.c
fib6_notifier.c
fib6_rules.c	ipv6: honor RT6_LOOKUP_F_DST_NOREF in rule lookup logic	2019-06-23 13:24:17 -07:00
fou6.c
icmp.c
inet6_connection_sock.c
inet6_hashtables.c
ip6_checksum.c
ip6_fib.c	ip6_fib: Don't discard nodes with valid routing information in fib6_locate_1()	2019-06-24 10:18:49 -07:00
ip6_flowlabel.c
ip6_gre.c
ip6_icmp.c
ip6_input.c
ip6_offload.c
ip6_offload.h
ip6_output.c
ip6_tunnel.c
ip6_udp_tunnel.c
ip6_vti.c
ip6mr.c
ipcomp6.c
ipv6_sockglue.c
Kconfig
Makefile
mcast_snoop.c
mcast.c
mip6.c
ndisc.c
netfilter.c
output_core.c
ping.c
proc.c
protocol.c
raw.c
reassembly.c
route.c	ipv6: fix suspicious RCU usage in rt6_dump_route()	2019-06-26 09:07:50 -07:00
seg6_hmac.c
seg6_iptunnel.c
seg6_local.c
seg6.c
sit.c
syncookies.c
sysctl_net_ipv6.c
tcp_ipv6.c
tcpv6_offload.c
tunnel6.c
udp_impl.h
udp_offload.c
udp.c
udplite.c
xfrm6_input.c
xfrm6_output.c
xfrm6_policy.c
xfrm6_protocol.c
xfrm6_state.c
xfrm6_tunnel.c