linux/net
Eric Dumazet 9b0a8da8c4 net/ipv6: respect rcu grace period before freeing fib6_info
syzbot reported use after free that is caused by fib6_info being
freed without a proper RCU grace period.

CPU: 0 PID: 1407 Comm: udevd Not tainted 4.17.0+ #39
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 __read_once_size include/linux/compiler.h:188 [inline]
 find_rr_leaf net/ipv6/route.c:705 [inline]
 rt6_select net/ipv6/route.c:761 [inline]
 fib6_table_lookup+0x12b7/0x14d0 net/ipv6/route.c:1823
 ip6_pol_route+0x1c2/0x1020 net/ipv6/route.c:1856
 ip6_pol_route_output+0x54/0x70 net/ipv6/route.c:2082
 fib6_rule_lookup+0x211/0x6d0 net/ipv6/fib6_rules.c:122
 ip6_route_output_flags+0x2c5/0x350 net/ipv6/route.c:2110
 ip6_route_output include/net/ip6_route.h:82 [inline]
 icmpv6_xrlim_allow net/ipv6/icmp.c:211 [inline]
 icmp6_send+0x147c/0x2da0 net/ipv6/icmp.c:535
 icmpv6_send+0x17a/0x300 net/ipv6/ip6_icmp.c:43
 ip6_link_failure+0xa5/0x790 net/ipv6/route.c:2244
 dst_link_failure include/net/dst.h:427 [inline]
 ndisc_error_report+0xd1/0x1c0 net/ipv6/ndisc.c:695
 neigh_invalidate+0x246/0x550 net/core/neighbour.c:892
 neigh_timer_handler+0xaf9/0xde0 net/core/neighbour.c:978
 call_timer_fn+0x230/0x940 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0x79e/0xc50 kernel/time/timer.c:1666
 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692
 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:284
 invoke_softirq kernel/softirq.c:364 [inline]
 irq_exit+0x1d1/0x200 kernel/softirq.c:404
 exiting_irq arch/x86/include/asm/apic.h:527 [inline]
 smp_apic_timer_interrupt+0x17e/0x710 arch/x86/kernel/apic/apic.c:1052
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863
 </IRQ>
RIP: 0010:strlen+0x5e/0xa0 lib/string.c:482
Code: 24 00 74 3b 48 bb 00 00 00 00 00 fc ff df 4c 89 e0 48 83 c0 01 48 89 c2 48 89 c1 48 c1 ea 03 83 e1 07 0f b6 14 1a 38 ca 7f 04 <84> d2 75 23 80 38 00 75 de 48 83 c4 08 4c 29 e0 5b 41 5c 5d c3 48
RSP: 0018:ffff8801af117850 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: ffff880197f53bd0 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81c5b06c RDI: ffff880197f53bc0
RBP: ffff8801af117868 R08: ffff88019a976540 R09: 0000000000000000
R10: ffff88019a976540 R11: 0000000000000000 R12: ffff880197f53bc0
R13: ffff880197f53bc0 R14: ffffffff899e4e90 R15: ffff8801d91c6a00
 strlen include/linux/string.h:267 [inline]
 getname_kernel+0x24/0x370 fs/namei.c:218
 open_exec+0x17/0x70 fs/exec.c:882
 load_elf_binary+0x968/0x5610 fs/binfmt_elf.c:780
 search_binary_handler+0x17d/0x570 fs/exec.c:1653
 exec_binprm fs/exec.c:1695 [inline]
 __do_execve_file.isra.35+0x16fe/0x2710 fs/exec.c:1819
 do_execveat_common fs/exec.c:1866 [inline]
 do_execve fs/exec.c:1883 [inline]
 __do_sys_execve fs/exec.c:1964 [inline]
 __se_sys_execve fs/exec.c:1959 [inline]
 __x64_sys_execve+0x8f/0xc0 fs/exec.c:1959
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f1576a46207
Code: 77 19 f4 48 89 d7 44 89 c0 0f 05 48 3d 00 f0 ff ff 76 e0 f7 d8 64 41 89 01 eb d8 f7 d8 64 41 89 01 eb df b8 3b 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 02 f3 c3 48 8b 15 00 8c 2d 00 f7 d8 64 89 02
RSP: 002b:00007ffff2784568 EFLAGS: 00000202 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f1576a46207
RDX: 0000000001215b10 RSI: 00007ffff2784660 RDI: 00007ffff2785670
RBP: 0000000000625500 R08: 000000000000589c R09: 000000000000589c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000001215b10
R13: 0000000000000007 R14: 0000000001204250 R15: 0000000000000005

Allocated by task 12188:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
 kmem_cache_alloc_trace+0x152/0x780 mm/slab.c:3620
 kmalloc include/linux/slab.h:513 [inline]
 kzalloc include/linux/slab.h:706 [inline]
 fib6_info_alloc+0xbb/0x280 net/ipv6/ip6_fib.c:152
 ip6_route_info_create+0x782/0x2b50 net/ipv6/route.c:3013
 ip6_route_add+0x23/0xb0 net/ipv6/route.c:3154
 ipv6_route_ioctl+0x5a5/0x760 net/ipv6/route.c:3660
 inet6_ioctl+0x100/0x1f0 net/ipv6/af_inet6.c:546
 sock_do_ioctl+0xe4/0x3e0 net/socket.c:973
 sock_ioctl+0x30d/0x680 net/socket.c:1097
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1cf/0x16f0 fs/ioctl.c:684
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701
 __do_sys_ioctl fs/ioctl.c:708 [inline]
 __se_sys_ioctl fs/ioctl.c:706 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:706
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 1402:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xd9/0x260 mm/slab.c:3813
 fib6_info_destroy+0x29b/0x350 net/ipv6/ip6_fib.c:207
 fib6_info_release include/net/ip6_fib.h:286 [inline]
 __ip6_del_rt_siblings net/ipv6/route.c:3235 [inline]
 ip6_route_del+0x11c4/0x13b0 net/ipv6/route.c:3316
 ipv6_route_ioctl+0x616/0x760 net/ipv6/route.c:3663
 inet6_ioctl+0x100/0x1f0 net/ipv6/af_inet6.c:546
 sock_do_ioctl+0xe4/0x3e0 net/socket.c:973
 sock_ioctl+0x30d/0x680 net/socket.c:1097
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1cf/0x16f0 fs/ioctl.c:684
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701
 __do_sys_ioctl fs/ioctl.c:708 [inline]
 __se_sys_ioctl fs/ioctl.c:706 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:706
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8801b5df2580
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 8 bytes inside of
 256-byte region [ffff8801b5df2580, ffff8801b5df2680)
The buggy address belongs to the page:
page:ffffea0006d77c80 count:1 mapcount:0 mapping:ffff8801da8007c0 index:0xffff8801b5df2e40
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffffea0006c5cc48 ffffea0007363308 ffff8801da8007c0
raw: ffff8801b5df2e40 ffff8801b5df2080 0000000100000006 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801b5df2480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801b5df2500: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
> ffff8801b5df2580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff8801b5df2600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801b5df2680: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb

Fixes: a64efe142f ("net/ipv6: introduce fib6_info struct and helpers")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Ahern <dsahern@gmail.com>
Reported-by: syzbot+9e6d75e3edef427ee888@syzkaller.appspotmail.com
Acked-by: David Ahern <dsahern@gmail.com>
Tested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-20 07:57:23 +09:00
..
6lowpan
9p treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
802
8021q Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
appletalk Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
atm atm: Preserve value of skb->truesize when accounting to vcc 2018-06-17 08:27:01 +09:00
ax25 Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
batman-adv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-05-26 19:46:15 -04:00
bluetooth treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
bpf bpf: making bpf_prog_test run aware of possible data_end ptr change 2018-04-18 23:34:16 +02:00
bpfilter bpfilter: fix race in pipe access 2018-06-07 20:07:28 -04:00
bridge Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-06-16 07:39:34 +09:00
caif net/caif: convert to ->poll_mask 2018-05-26 09:16:44 +02:00
can treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
ceph The main piece is a set of libceph changes that revamps how OSD 2018-06-15 07:24:58 +09:00
core Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2018-06-17 07:54:24 +09:00
dcb treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
dccp treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
decnet Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
dns_resolver KEYS: DNS: limit the length of option strings 2018-04-17 15:17:41 -04:00
dsa net: dsa: add error handling for pskb_trim_rcsum 2018-06-11 14:19:38 -07:00
ethernet net: core: rework basic flow dissection helper 2018-05-08 00:02:36 -04:00
hsr
ieee802154 treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
ife net: sched: ife: check on metadata length 2018-04-22 21:12:00 -04:00
ipv4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-06-16 07:39:34 +09:00
ipv6 net/ipv6: respect rcu grace period before freeing fib6_info 2018-06-20 07:57:23 +09:00
iucv net/iucv: convert to ->poll_mask 2018-05-26 09:16:44 +02:00
kcm Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
key Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
l2tp l2tp: filter out non-PPP sessions in pppol2tp_tunnel_ioctl() 2018-06-15 09:12:37 -07:00
l3mdev
lapb
llc Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
mac80211 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-06-16 07:39:34 +09:00
mac802154 net/mac802154: disambiguate mac80215 vs mac802154 trace events 2018-03-28 22:55:18 +02:00
mpls net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
ncsi net/ncsi: Use netdev_dbg for debug messages 2018-06-20 07:26:58 +09:00
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-06-16 07:39:34 +09:00
netlabel audit: use inline function to get audit context 2018-05-14 17:24:18 -04:00
netlink treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
netrom treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
nfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
nsh nsh: fix infinite loop 2018-05-04 12:54:38 -04:00
openvswitch treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
packet treewide: Use array_size() in vzalloc() 2018-06-12 16:19:22 -07:00
phonet Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
psample
qrtr Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
rds Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-06-16 07:39:34 +09:00
rfkill rfkill: Create rfkill-none LED trigger 2018-05-23 11:26:45 +02:00
rose treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
rxrpc treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
sched net_sched: blackhole: tell upper qdisc about dropped packets 2018-06-17 08:42:33 +09:00
sctp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-06-16 07:39:34 +09:00
smc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-06-16 07:39:34 +09:00
strparser strparser: Add __strp_unpause and use it in ktls. 2018-06-06 14:07:53 -04:00
sunrpc - Error path bug fix for overflow tests (Dan) 2018-06-12 18:28:00 -07:00
switchdev
tipc treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
tls tls: fix waitall behavior in tls_sw_recvmsg 2018-06-15 09:14:30 -07:00
unix Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
vmw_vsock net/vmw_vsock: convert to ->poll_mask 2018-05-26 09:16:44 +02:00
wimax
wireless Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-06-16 07:39:34 +09:00
x25 Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
xdp xsk: re-add queue id check for XDP_SKB path 2018-06-12 12:19:04 +02:00
xfrm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
compat.c net: support compat 64-bit time in {s,g}etsockopt 2018-04-27 19:46:06 -04:00
Kconfig net: Introduce generic failover module 2018-05-28 22:59:54 -04:00
Makefile bpfilter: switch to CC from HOSTCC 2018-06-05 10:21:18 -04:00
socket.c socket: close race condition between sock_close() and sockfs_setattr() 2018-06-10 12:25:53 -07:00
sysctl_net.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00