bianbu-linux-6.6/net/ipv6
Eric Dumazet af1dde074e ipv6: prevent UAF in ip6_send_skb()
[ Upstream commit faa389b2fbaaec7fd27a390b4896139f9da662e3 ]

syzbot reported an UAF in ip6_send_skb() [1]

After ip6_local_out() has returned, we no longer can safely
dereference rt, unless we hold rcu_read_lock().

A similar issue has been fixed in commit
a688caa34b ("ipv6: take rcu lock in rawv6_send_hdrinc()")

Another potential issue in ip6_finish_output2() is handled in a
separate patch.

[1]
 BUG: KASAN: slab-use-after-free in ip6_send_skb+0x18d/0x230 net/ipv6/ip6_output.c:1964
Read of size 8 at addr ffff88806dde4858 by task syz.1.380/6530

CPU: 1 UID: 0 PID: 6530 Comm: syz.1.380 Not tainted 6.11.0-rc3-syzkaller-00306-gdf6cbc62cc9b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
  __dump_stack lib/dump_stack.c:93 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
  print_address_description mm/kasan/report.c:377 [inline]
  print_report+0x169/0x550 mm/kasan/report.c:488
  kasan_report+0x143/0x180 mm/kasan/report.c:601
  ip6_send_skb+0x18d/0x230 net/ipv6/ip6_output.c:1964
  rawv6_push_pending_frames+0x75c/0x9e0 net/ipv6/raw.c:588
  rawv6_sendmsg+0x19c7/0x23c0 net/ipv6/raw.c:926
  sock_sendmsg_nosec net/socket.c:730 [inline]
  __sock_sendmsg+0x1a6/0x270 net/socket.c:745
  sock_write_iter+0x2dd/0x400 net/socket.c:1160
 do_iter_readv_writev+0x60a/0x890
  vfs_writev+0x37c/0xbb0 fs/read_write.c:971
  do_writev+0x1b1/0x350 fs/read_write.c:1018
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f936bf79e79
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f936cd7f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f936c115f80 RCX: 00007f936bf79e79
RDX: 0000000000000001 RSI: 0000000020000040 RDI: 0000000000000004
RBP: 00007f936bfe7916 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f936c115f80 R15: 00007fff2860a7a8
 </TASK>

Allocated by task 6530:
  kasan_save_stack mm/kasan/common.c:47 [inline]
  kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
  unpoison_slab_object mm/kasan/common.c:312 [inline]
  __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338
  kasan_slab_alloc include/linux/kasan.h:201 [inline]
  slab_post_alloc_hook mm/slub.c:3988 [inline]
  slab_alloc_node mm/slub.c:4037 [inline]
  kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4044
  dst_alloc+0x12b/0x190 net/core/dst.c:89
  ip6_blackhole_route+0x59/0x340 net/ipv6/route.c:2670
  make_blackhole net/xfrm/xfrm_policy.c:3120 [inline]
  xfrm_lookup_route+0xd1/0x1c0 net/xfrm/xfrm_policy.c:3313
  ip6_dst_lookup_flow+0x13e/0x180 net/ipv6/ip6_output.c:1257
  rawv6_sendmsg+0x1283/0x23c0 net/ipv6/raw.c:898
  sock_sendmsg_nosec net/socket.c:730 [inline]
  __sock_sendmsg+0x1a6/0x270 net/socket.c:745
  ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597
  ___sys_sendmsg net/socket.c:2651 [inline]
  __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2680
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 45:
  kasan_save_stack mm/kasan/common.c:47 [inline]
  kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
  kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
  poison_slab_object+0xe0/0x150 mm/kasan/common.c:240
  __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
  kasan_slab_free include/linux/kasan.h:184 [inline]
  slab_free_hook mm/slub.c:2252 [inline]
  slab_free mm/slub.c:4473 [inline]
  kmem_cache_free+0x145/0x350 mm/slub.c:4548
  dst_destroy+0x2ac/0x460 net/core/dst.c:124
  rcu_do_batch kernel/rcu/tree.c:2569 [inline]
  rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2843
  handle_softirqs+0x2c4/0x970 kernel/softirq.c:554
  __do_softirq kernel/softirq.c:588 [inline]
  invoke_softirq kernel/softirq.c:428 [inline]
  __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637
  irq_exit_rcu+0x9/0x30 kernel/softirq.c:649
  instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
  sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
  asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

Last potentially related work creation:
  kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
  __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541
  __call_rcu_common kernel/rcu/tree.c:3106 [inline]
  call_rcu+0x167/0xa70 kernel/rcu/tree.c:3210
  refdst_drop include/net/dst.h:263 [inline]
  skb_dst_drop include/net/dst.h:275 [inline]
  nf_ct_frag6_queue net/ipv6/netfilter/nf_conntrack_reasm.c:306 [inline]
  nf_ct_frag6_gather+0xb9a/0x2080 net/ipv6/netfilter/nf_conntrack_reasm.c:485
  ipv6_defrag+0x2c8/0x3c0 net/ipv6/netfilter/nf_defrag_ipv6_hooks.c:67
  nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
  nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626
  nf_hook include/linux/netfilter.h:269 [inline]
  __ip6_local_out+0x6fa/0x800 net/ipv6/output_core.c:143
  ip6_local_out+0x26/0x70 net/ipv6/output_core.c:153
  ip6_send_skb+0x112/0x230 net/ipv6/ip6_output.c:1959
  rawv6_push_pending_frames+0x75c/0x9e0 net/ipv6/raw.c:588
  rawv6_sendmsg+0x19c7/0x23c0 net/ipv6/raw.c:926
  sock_sendmsg_nosec net/socket.c:730 [inline]
  __sock_sendmsg+0x1a6/0x270 net/socket.c:745
  sock_write_iter+0x2dd/0x400 net/socket.c:1160
 do_iter_readv_writev+0x60a/0x890

Fixes: 0625491493 ("ipv6: ip6_push_pending_frames() should increment IPSTATS_MIB_OUTDISCARDS")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20240820160859.3786976-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-08-29 17:33:49 +02:00
..
ila ila: block BH in ila_output() 2024-07-25 09:50:43 +02:00
netfilter netfilter: allow ipv6 fragments to arrive on different devices 2024-08-29 17:33:19 +02:00
addrconf.c ipv6: take care of scope when choosing the src addr 2024-08-03 08:54:13 +02:00
addrconf_core.c ipv6: Ensure natural alignment of const ipv6 loopback and router addresses 2024-02-05 20:14:36 +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 bpf: Derive source IP addr via bpf_*_fib_lookup() 2024-03-01 13:35:04 +01:00
ah6.c net: ipv6: Remove completion function scaffolding 2023-02-13 18:35:15 +08:00
anycast.c IPv6: add extack info for IPv6 address add/delete 2023-07-28 11:01:56 +01:00
calipso.c cipso,calipso: resolve a number of problems with the DOI refcounts 2021-03-04 15:26:57 -08:00
datagram.c inet: introduce inet->inet_flags 2023-08-16 11:09:16 +01:00
esp6.c net: esp: cleanup esp_output_tail_tcp() in case of unsupported ESPINTCP 2024-08-03 08:53:36 +02:00
esp6_offload.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-06-22 18:40:38 -07:00
exthdrs.c Fix write to cloned skb in ipv6_hop_ioam() 2024-03-01 13:35:10 +01:00
exthdrs_core.c ipv6: Fix out-of-bounds access in ipv6_find_tlv() 2023-05-24 08:43:39 +01:00
exthdrs_offload.c
fib6_notifier.c net: fib_notifier: propagate extack down to the notifier block callback 2019-10-04 11:10:56 -07:00
fib6_rules.c ipv6: fib6_rules: avoid possible NULL dereference in fib6_rule_action() 2024-05-17 12:02:23 +02:00
fou6.c net: Add MODULE_DESCRIPTION entries to network modules 2020-06-20 21:33:57 -07:00
icmp.c sysctl-6.6-rc1 2023-08-29 17:39:15 -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 net: remove duplicate INDIRECT_CALLABLE_DECLARE of udp[6]_ehashfn 2023-07-31 13:53:10 -07:00
ioam6.c genetlink: start to validate reserved header bytes 2022-08-29 12:47:15 +01:00
ioam6_iptunnel.c ipv6: ioam: block BH from ioam6_output() 2024-06-21 14:38:15 +02:00
ip6_checksum.c
ip6_fib.c ipv6: fix possible race in __fib6_drop_pcpu_from() 2024-06-21 14:38:20 +02:00
ip6_flowlabel.c ipv6: flowlabel: do not disable BH where not needed 2023-03-21 21:32:18 -07:00
ip6_gre.c net: add netdev_lockdep_set_classes() to virtual drivers 2024-04-13 13:07:30 +02:00
ip6_icmp.c net: icmp: pass zeroed opts from icmp{,v6}_ndo_send before sending 2021-02-23 11:29:52 -08:00
ip6_input.c ipv6: annotate data-races around cnf.disable_ipv6 2024-05-17 12:02:24 +02:00
ip6_offload.c net: gro: fix udp bad offset in socket lookup by adding {inner_}network_offset to napi_gro_cb 2024-05-17 12:02:07 +02:00
ip6_offload.h
ip6_output.c ipv6: prevent UAF in ip6_send_skb() 2024-08-29 17:33:49 +02:00
ip6_tunnel.c ip6_tunnel: Fix broken GRO 2024-08-29 17:33:47 +02:00
ip6_udp_tunnel.c net: Make locking in sock_bindtoindex optional 2020-06-01 14:57:14 -07:00
ip6_vti.c net: add netdev_lockdep_set_classes() to virtual drivers 2024-04-13 13:07:30 +02:00
ip6mr.c net: ipv4, ipv6: fix IPSTATS_MIB_OUTOCTETS increment duplicated 2023-08-30 09:44:09 +01:00
ipcomp6.c xfrm: ipcomp: add extack to ipcomp{4,6}_init_state 2022-09-29 07:18:00 +02:00
ipv6_sockglue.c net: selectively purge error queue in IP_RECVERR / IPV6_RECVERR 2023-08-20 15:17:47 +01:00
Kconfig ipv6: fix indentation of a config attribute 2023-08-16 10:03:08 +01:00
Makefile net: ipv6: use ipv6-y directly instead of ipv6-objs 2021-09-28 13:13:40 +01:00
mcast.c net: fix IPSTATS_MIB_OUTPKGS increment in OutForwDatagrams. 2024-04-03 15:28:39 +02:00
mcast_snoop.c net: bridge: mcast: fix broken length + header check for MRDv6 Adv. 2021-04-27 14:02:06 -07:00
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 ipv6: fix ndisc_is_useropt() handling for PIO 2024-08-11 12:47:23 +02:00
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 bpf: Propagate modified uaddrlen from cgroup sockaddr programs 2024-01-31 16:19:04 -08:00
proc.c net: fix IPSTATS_MIB_OUTPKGS increment in OutForwDatagrams. 2024-04-03 15:28:39 +02:00
protocol.c
raw.c net: fix IPSTATS_MIB_OUTPKGS increment in OutForwDatagrams. 2024-04-03 15:28:39 +02:00
reassembly.c net: ipv6: fix wrong start position when receive hop-by-hop fragment 2024-06-12 11:11:51 +02:00
route.c ipv6: fix source address selection with route leak 2024-08-14 13:59:03 +02:00
rpl.c ipv6: rpl: Remove pskb(_may)?_pull() in ipv6_rpl_srh_rcv(). 2023-06-19 11:32:58 -07:00
rpl_iptunnel.c net: ipv6: rpl_iptunnel: block BH in rpl_output() and rpl_input() 2024-07-25 09:50:43 +02:00
seg6.c ipv6: sr: fix invalid unregister error path 2024-06-12 11:11:53 +02:00
seg6_hmac.c ipv6: sr: fix memleak in seg6_hmac_init_algo 2024-06-12 11:12:48 +02:00
seg6_iptunnel.c ipv6: sr: block BH in seg6_output_core() and seg6_input_core() 2024-06-21 14:38:16 +02:00
seg6_local.c seg6: fix parameter passing when calling NF_HOOK() in End.DX4 and End.DX6 behaviors 2024-06-27 13:49:08 +02:00
sit.c net: add netdev_lockdep_set_classes() to virtual drivers 2024-04-13 13:07:30 +02:00
syncookies.c tcp: annotate data-races around tp->window_clamp 2024-08-11 12:47:19 +02:00
sysctl_net_ipv6.c networking: Update to register_net_sysctl_sz 2023-08-15 15:26:18 -07:00
tcp_ipv6.c tcp/dccp: do not care about families in inet_twsk_purge() 2024-08-29 17:33:46 +02:00
tcpv6_offload.c net: Make gro complete function to return void 2023-05-31 09:50:17 +01:00
tunnel6.c tunnel6: add tunnel6_input_afinfo for ipip and ipv6 tunnels 2020-07-09 12:52:37 +02:00
udp.c udp: Avoid call to compute_score on multiple sites 2024-06-12 11:11:42 +02:00
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 net: gro: fix udp bad offset in socket lookup by adding {inner_}network_offset to napi_gro_cb 2024-05-17 12:02:07 +02:00
udplite.c udplite: remove UDPLITE_BIT 2023-11-20 11:58:56 +01:00
xfrm6_input.c xfrm: Preserve vlan tags for transport mode software GRO 2024-05-17 12:02:20 +02:00
xfrm6_output.c xfrm: fix tunnel model fragmentation behavior 2022-03-01 12:08:40 +01:00
xfrm6_policy.c xfrm6: check ip6_dst_idev() return value in xfrm6_get_saddr() 2024-06-27 13:49:06 +02:00
xfrm6_protocol.c xfrm: add support for UDPv6 encapsulation of ESP 2020-04-28 11:28:36 +02:00
xfrm6_state.c xfrm: remove output_finish indirection from xfrm_state_afinfo 2020-05-06 09:40:08 +02:00
xfrm6_tunnel.c xfrm: tunnel: add extack to ipip_init_state, xfrm6_tunnel_init_state 2022-09-29 07:18:00 +02:00