linux/net/ipv4
Kuniyuki Iwashima a3f2c083cb arp: Prevent overflow in arp_req_get().
[ Upstream commit a7d6027790 ]

syzkaller reported an overflown write in arp_req_get(). [0]

When ioctl(SIOCGARP) is issued, arp_req_get() looks up an neighbour
entry and copies neigh->ha to struct arpreq.arp_ha.sa_data.

The arp_ha here is struct sockaddr, not struct sockaddr_storage, so
the sa_data buffer is just 14 bytes.

In the splat below, 2 bytes are overflown to the next int field,
arp_flags.  We initialise the field just after the memcpy(), so it's
not a problem.

However, when dev->addr_len is greater than 22 (e.g. MAX_ADDR_LEN),
arp_netmask is overwritten, which could be set as htonl(0xFFFFFFFFUL)
in arp_ioctl() before calling arp_req_get().

To avoid the overflow, let's limit the max length of memcpy().

Note that commit b5f0de6df6 ("net: dev: Convert sa_data to flexible
array in struct sockaddr") just silenced syzkaller.

[0]:
memcpy: detected field-spanning write (size 16) of single field "r->arp_ha.sa_data" at net/ipv4/arp.c:1128 (size 14)
WARNING: CPU: 0 PID: 144638 at net/ipv4/arp.c:1128 arp_req_get+0x411/0x4a0 net/ipv4/arp.c:1128
Modules linked in:
CPU: 0 PID: 144638 Comm: syz-executor.4 Not tainted 6.1.74 #31
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-5 04/01/2014
RIP: 0010:arp_req_get+0x411/0x4a0 net/ipv4/arp.c:1128
Code: fd ff ff e8 41 42 de fb b9 0e 00 00 00 4c 89 fe 48 c7 c2 20 6d ab 87 48 c7 c7 80 6d ab 87 c6 05 25 af 72 04 01 e8 5f 8d ad fb <0f> 0b e9 6c fd ff ff e8 13 42 de fb be 03 00 00 00 4c 89 e7 e8 a6
RSP: 0018:ffffc900050b7998 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff88803a815000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8641a44a RDI: 0000000000000001
RBP: ffffc900050b7a98 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 203a7970636d656d R12: ffff888039c54000
R13: 1ffff92000a16f37 R14: ffff88803a815084 R15: 0000000000000010
FS:  00007f172bf306c0(0000) GS:ffff88805aa00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f172b3569f0 CR3: 0000000057f12005 CR4: 0000000000770ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <TASK>
 arp_ioctl+0x33f/0x4b0 net/ipv4/arp.c:1261
 inet_ioctl+0x314/0x3a0 net/ipv4/af_inet.c:981
 sock_do_ioctl+0xdf/0x260 net/socket.c:1204
 sock_ioctl+0x3ef/0x650 net/socket.c:1321
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x18e/0x220 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x37/0x90 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x64/0xce
RIP: 0033:0x7f172b262b8d
Code: 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f172bf300b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f172b3abf80 RCX: 00007f172b262b8d
RDX: 0000000020000000 RSI: 0000000000008954 RDI: 0000000000000003
RBP: 00007f172b2d3493 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f172b3abf80 R15: 00007f172bf10000
 </TASK>

Reported-by: syzkaller <syzkaller@googlegroups.com>
Reported-by: Bjoern Doebel <doebel@amazon.de>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240215230516.31330-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2024-03-01 13:35:08 +01:00
..
bpfilter net: Use umd_cleanup_helper() 2023-05-31 13:06:57 +02:00
netfilter netfilter: bridge: replace physindev with physinif in nf_bridge_info 2024-01-25 15:35:59 -08:00
af_inet.c inet: read sk->sk_family once in inet_recv_error() 2024-02-16 19:10:49 +01:00
ah4.c net: ipv4: Remove completion function scaffolding 2023-02-13 18:35:15 +08:00
arp.c arp: Prevent overflow in arp_req_get(). 2024-03-01 13:35:08 +01:00
bpf_tcp_ca.c bpf: Drop useless btf_vmlinux in bpf_tcp_ca 2023-07-18 17:31:10 -07:00
cipso_ipv4.c inet: move inet->is_icsk to inet->inet_flags 2023-08-16 11:09:17 +01:00
datagram.c ipv4: fix data-races around inet->inet_id 2023-08-20 11:40:49 +01:00
devinet.c ipv4: properly combine dev_base_seq and ipv4.dev_addr_genid 2024-03-01 13:35:07 +01:00
esp4.c net: ipv4: fix typo in comments 2023-10-25 10:38:07 +01:00
esp4_offload.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-06-22 18:40:38 -07:00
fib_frontend.c ipv4: Fix incorrect table ID in IOCTL path 2023-03-16 17:26:31 -07:00
fib_lookup.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-02-17 11:44:20 -08:00
fib_notifier.c net: ipv4: remove superfluous header files from fib_notifier.c 2021-09-28 17:32:56 -07:00
fib_rules.c ipv4: remove unnecessary type castings 2022-04-30 15:12:58 +01:00
fib_semantics.c ipv4: fib: annotate races around nh->nh_saddr_genid and nh->nh_saddr 2023-10-18 18:11:31 -07:00
fib_trie.c ipv4/fib: send notify when delete source address routes 2023-10-03 09:00:40 +02:00
fou_bpf.c bpf,fou: Add bpf_skb_{set,get}_fou_encap kfuncs 2023-04-12 16:40:39 -07:00
fou_core.c bpf,fou: Add bpf_skb_{set,get}_fou_encap kfuncs 2023-04-12 16:40:39 -07:00
fou_nl.c net: ynl: prefix uAPI header include with uapi/ 2023-05-26 10:30:14 +01:00
fou_nl.h net: ynl: prefix uAPI header include with uapi/ 2023-05-26 10:30:14 +01:00
gre_demux.c net: Remove the member netns_ok 2021-05-17 15:29:35 -07:00
gre_offload.c net: move gso declarations and functions to their own files 2023-06-10 00:11:41 -07:00
icmp.c icmp: guard against too small mtu 2023-03-31 21:37:06 -07:00
igmp.c ipv4: igmp: fix refcnt uaf issue when receiving igmp query packet 2023-12-08 08:52:21 +01:00
inet_connection_sock.c tcp: make sure init the accept_queue's spinlocks once 2024-01-31 16:19:00 -08:00
inet_diag.c inet: move inet->defer_connect to inet->inet_flags 2023-08-16 11:09:18 +01:00
inet_fragment.c net: dropreason: add SKB_DROP_REASON_FRAG_REASM_TIMEOUT 2022-10-31 20:14:27 -07:00
inet_hashtables.c dccp/tcp: Unhash sk from ehash for tb2 alloc failure after check_estalblished(). 2024-03-01 13:35:06 +01:00
inet_timewait_sock.c inet: move inet->transparent to inet->inet_flags 2023-08-16 11:09:17 +01:00
inetpeer.c inetpeer: Fix data-races around sysctl. 2022-07-08 12:10:33 +01:00
ip_forward.c net: ipv4, ipv6: fix IPSTATS_MIB_OUTOCTETS increment duplicated 2023-08-30 09:44:09 +01:00
ip_fragment.c networking: Update to register_net_sysctl_sz 2023-08-15 15:26:18 -07:00
ip_gre.c ipv4: ip_gre: Avoid skb_pull() failure in ipgre_xmit() 2023-12-13 18:45:07 +01:00
ip_input.c ipv4: ignore dst hint for multipath routes 2023-09-01 08:11:51 +01:00
ip_options.c ipv4: drop fragmentation code from ip_options_build() 2022-01-29 17:53:07 +00:00
ip_output.c net: ipv4: fix a memleak in ip_setup_cork 2024-02-05 20:14:36 +00:00
ip_sockglue.c ipmr: fix kernel panic when forwarding mcast packets 2024-02-05 20:14:35 +00:00
ip_tunnel.c bpf-next-for-netdev 2023-04-13 16:43:38 -07:00
ip_tunnel_core.c tunnels: fix out of bounds access when building IPv6 PMTU error 2024-02-16 19:10:48 +01:00
ip_vti.c ip_vti: fix potential slab-use-after-free in decode_session6 2023-07-11 11:06:08 +02:00
ipcomp.c xfrm: ipcomp: add extack to ipcomp{4,6}_init_state 2022-09-29 07:18:00 +02:00
ipconfig.c net: ipconfig: move ic_nameservers_fallback into #ifdef block 2023-05-22 11:17:55 +01:00
ipip.c ipip,ip_tunnel,sit: Add FOU support for externally controlled ipip devices 2023-04-12 16:40:39 -07:00
ipmr.c ipmr: fix kernel panic when forwarding mcast packets 2024-02-05 20:14:35 +00:00
ipmr_base.c ipmr: adopt rcu_read_lock() in mr_dump() 2022-06-24 11:34:38 +01:00
Kconfig tcp: configurable source port perturb table size 2022-11-16 13:02:04 +00:00
Makefile bpf,fou: Add bpf_skb_{set,get}_fou_encap kfuncs 2023-04-12 16:40:39 -07:00
metrics.c ipv4: prevent potential spectre v1 gadget in ip_metrics_convert() 2023-01-23 21:37:25 -08:00
netfilter.c netfilter: Use l3mdev flow key when re-routing mangled packets 2022-05-16 13:03:29 +02:00
netlink.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
nexthop.c nexthop: Do not increment dump sentinel at the end of the dump 2023-08-15 18:54:53 -07:00
ping.c bpf: Propagate modified uaddrlen from cgroup sockaddr programs 2024-01-31 16:19:04 -08:00
proc.c icmp: Add counters for rate limits 2023-01-26 10:52:18 +01:00
protocol.c net: Remove the member netns_ok 2021-05-17 15:29:35 -07:00
raw.c ipmr: fix kernel panic when forwarding mcast packets 2024-02-05 20:14:35 +00:00
raw_diag.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-04-06 12:01:20 -07:00
route.c ipv4: Correct/silence an endian warning in __ip_do_redirect 2023-12-03 07:33:04 +01:00
syncookies.c tcp: fix cookie_init_timestamp() overflows 2023-11-20 11:59:01 +01:00
sysctl_net_ipv4.c networking: Update to register_net_sysctl_sz 2023-08-15 15:26:18 -07:00
tcp.c tcp: add sanity checks to rx zerocopy 2024-02-05 20:14:35 +00:00
tcp_bbr.c bpf: Add __bpf_kfunc tag to all kfuncs 2023-02-02 00:25:14 +01:00
tcp_bic.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_bpf.c tcp_bpf: properly release resources on error paths 2023-10-18 18:09:31 -07:00
tcp_cdg.c Random number generator fixes for Linux 6.1-rc1. 2022-10-16 15:27:07 -07:00
tcp_cong.c net: Update an existing TCP congestion control algorithm. 2023-03-22 22:53:00 -07:00
tcp_cubic.c bpf: Add __bpf_kfunc tag to all kfuncs 2023-02-02 00:25:14 +01:00
tcp_dctcp.c bpf: Add __bpf_kfunc tag to all kfuncs 2023-02-02 00:25:14 +01:00
tcp_dctcp.h tcp: refactor DCTCP ECN ACK handling 2018-10-10 22:26:00 -07:00
tcp_diag.c tcp: Access &tcp_hashinfo via net. 2022-09-20 10:21:49 -07:00
tcp_fastopen.c inet: move inet->defer_connect to inet->inet_flags 2023-08-16 11:09:18 +01:00
tcp_highspeed.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_htcp.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_hybla.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_illinois.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_input.c tcp: do not accept ACK of bytes we never sent 2023-12-13 18:45:10 +01:00
tcp_ipv4.c bpf: Propagate modified uaddrlen from cgroup sockaddr programs 2024-01-31 16:19:04 -08:00
tcp_lp.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_metrics.c tcp_metrics: do not create an entry from tcp_init_metrics() 2023-11-20 11:58:59 +01:00
tcp_minisocks.c inet: move inet->transparent to inet->inet_flags 2023-08-16 11:09:17 +01:00
tcp_nv.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_offload.c net: move gso declarations and functions to their own files 2023-06-10 00:11:41 -07:00
tcp_output.c tcp: derive delack_max from rto_min 2024-01-10 17:16:54 +01:00
tcp_plb.c prandom: remove prandom_u32_max() 2022-12-20 03:13:45 +01:00
tcp_rate.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-04-28 13:02:01 -07:00
tcp_recovery.c tcp: fix excessive TLP and RACK timeouts from HZ rounding 2023-10-17 17:25:42 -07:00
tcp_scalable.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_timer.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-08-18 12:44:56 -07:00
tcp_ulp.c net/ulp: use consistent error code when blocking ULP 2023-01-19 09:26:16 -08:00
tcp_vegas.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_vegas.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tcp_veno.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_westwood.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tcp_yeah.c tcp: add accessors to read/set tp->snd_cwnd 2022-04-06 12:05:41 -07:00
tunnel4.c net: Remove the member netns_ok 2021-05-17 15:29:35 -07:00
udp.c ipmr: fix kernel panic when forwarding mcast packets 2024-02-05 20:14:35 +00:00
udp_bpf.c bpf, sockmap: Fix an infinite loop error when len is 0 in tcp_bpf_recvmsg_parser() 2023-03-03 17:25:15 +01:00
udp_diag.c udp: Access &udp_table via net. 2022-11-16 09:43:35 +00:00
udp_impl.h sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES) 2023-06-24 15:50:13 -07:00
udp_offload.c udp: move udp->gro_enabled to udp->udp_flags 2023-11-20 11:58:56 +01:00
udp_tunnel_core.c udp: lockless UDP_ENCAP_L2TPINUDP / UDP_GRO 2023-11-20 11:58:56 +01:00
udp_tunnel_nic.c udp_tunnel: Add checks for nla_nest_start() in __udp_tunnel_nic_dump_write() 2022-11-29 08:44:24 -08:00
udp_tunnel_stub.c udp_tunnel: add central NIC RX port offload infrastructure 2020-07-10 13:54:00 -07:00
udplite.c udplite: remove UDPLITE_BIT 2023-11-20 11:58:56 +01:00
xfrm4_input.c udp: annotate data-races around udp->encap_type 2023-11-20 11:58:56 +01:00
xfrm4_output.c xfrm: fix unused variable warning if CONFIG_NETFILTER=n 2020-05-11 15:12:27 +02:00
xfrm4_policy.c sysctl-6.6-rc1 2023-08-29 17:39:15 -07:00
xfrm4_protocol.c net: xfrm: unexport __init-annotated xfrm4_protocol_init() 2022-06-08 10:10:13 -07:00
xfrm4_state.c xfrm: remove output_finish indirection from xfrm_state_afinfo 2020-05-06 09:40:08 +02:00
xfrm4_tunnel.c xfrm: tunnel: add extack to ipip_init_state, xfrm6_tunnel_init_state 2022-09-29 07:18:00 +02:00