kernel_samsung_a53x/net/ipv6
Jiri Benc 4b6fb836c2 ipv6: fix race condition between ipv6_get_ifaddr and ipv6_del_addr
[ Upstream commit 7633c4da919ad51164acbf1aa322cc1a3ead6129 ]

Although ipv6_get_ifaddr walks inet6_addr_lst under the RCU lock, it
still means hlist_for_each_entry_rcu can return an item that got removed
from the list. The memory itself of such item is not freed thanks to RCU
but nothing guarantees the actual content of the memory is sane.

In particular, the reference count can be zero. This can happen if
ipv6_del_addr is called in parallel. ipv6_del_addr removes the entry
from inet6_addr_lst (hlist_del_init_rcu(&ifp->addr_lst)) and drops all
references (__in6_ifa_put(ifp) + in6_ifa_put(ifp)). With bad enough
timing, this can happen:

1. In ipv6_get_ifaddr, hlist_for_each_entry_rcu returns an entry.

2. Then, the whole ipv6_del_addr is executed for the given entry. The
   reference count drops to zero and kfree_rcu is scheduled.

3. ipv6_get_ifaddr continues and tries to increments the reference count
   (in6_ifa_hold).

4. The rcu is unlocked and the entry is freed.

5. The freed entry is returned.

Prevent increasing of the reference count in such case. The name
in6_ifa_hold_safe is chosen to mimic the existing fib6_info_hold_safe.

[   41.506330] refcount_t: addition on 0; use-after-free.
[   41.506760] WARNING: CPU: 0 PID: 595 at lib/refcount.c:25 refcount_warn_saturate+0xa5/0x130
[   41.507413] Modules linked in: veth bridge stp llc
[   41.507821] CPU: 0 PID: 595 Comm: python3 Not tainted 6.9.0-rc2.main-00208-g49563be82afa #14
[   41.508479] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
[   41.509163] RIP: 0010:refcount_warn_saturate+0xa5/0x130
[   41.509586] Code: ad ff 90 0f 0b 90 90 c3 cc cc cc cc 80 3d c0 30 ad 01 00 75 a0 c6 05 b7 30 ad 01 01 90 48 c7 c7 38 cc 7a 8c e8 cc 18 ad ff 90 <0f> 0b 90 90 c3 cc cc cc cc 80 3d 98 30 ad 01 00 0f 85 75 ff ff ff
[   41.510956] RSP: 0018:ffffbda3c026baf0 EFLAGS: 00010282
[   41.511368] RAX: 0000000000000000 RBX: ffff9e9c46914800 RCX: 0000000000000000
[   41.511910] RDX: ffff9e9c7ec29c00 RSI: ffff9e9c7ec1c900 RDI: ffff9e9c7ec1c900
[   41.512445] RBP: ffff9e9c43660c9c R08: 0000000000009ffb R09: 00000000ffffdfff
[   41.512998] R10: 00000000ffffdfff R11: ffffffff8ca58a40 R12: ffff9e9c4339a000
[   41.513534] R13: 0000000000000001 R14: ffff9e9c438a0000 R15: ffffbda3c026bb48
[   41.514086] FS:  00007fbc4cda1740(0000) GS:ffff9e9c7ec00000(0000) knlGS:0000000000000000
[   41.514726] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   41.515176] CR2: 000056233b337d88 CR3: 000000000376e006 CR4: 0000000000370ef0
[   41.515713] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   41.516252] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   41.516799] Call Trace:
[   41.517037]  <TASK>
[   41.517249]  ? __warn+0x7b/0x120
[   41.517535]  ? refcount_warn_saturate+0xa5/0x130
[   41.517923]  ? report_bug+0x164/0x190
[   41.518240]  ? handle_bug+0x3d/0x70
[   41.518541]  ? exc_invalid_op+0x17/0x70
[   41.520972]  ? asm_exc_invalid_op+0x1a/0x20
[   41.521325]  ? refcount_warn_saturate+0xa5/0x130
[   41.521708]  ipv6_get_ifaddr+0xda/0xe0
[   41.522035]  inet6_rtm_getaddr+0x342/0x3f0
[   41.522376]  ? __pfx_inet6_rtm_getaddr+0x10/0x10
[   41.522758]  rtnetlink_rcv_msg+0x334/0x3d0
[   41.523102]  ? netlink_unicast+0x30f/0x390
[   41.523445]  ? __pfx_rtnetlink_rcv_msg+0x10/0x10
[   41.523832]  netlink_rcv_skb+0x53/0x100
[   41.524157]  netlink_unicast+0x23b/0x390
[   41.524484]  netlink_sendmsg+0x1f2/0x440
[   41.524826]  __sys_sendto+0x1d8/0x1f0
[   41.525145]  __x64_sys_sendto+0x1f/0x30
[   41.525467]  do_syscall_64+0xa5/0x1b0
[   41.525794]  entry_SYSCALL_64_after_hwframe+0x72/0x7a
[   41.526213] RIP: 0033:0x7fbc4cfcea9a
[   41.526528] Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 7e c3 0f 1f 44 00 00 41 54 48 83 ec 30 44 89
[   41.527942] RSP: 002b:00007ffcf54012a8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[   41.528593] RAX: ffffffffffffffda RBX: 00007ffcf5401368 RCX: 00007fbc4cfcea9a
[   41.529173] RDX: 000000000000002c RSI: 00007fbc4b9d9bd0 RDI: 0000000000000005
[   41.529786] RBP: 00007fbc4bafb040 R08: 00007ffcf54013e0 R09: 000000000000000c
[   41.530375] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
[   41.530977] R13: ffffffffc4653600 R14: 0000000000000001 R15: 00007fbc4ca85d1b
[   41.531573]  </TASK>

Fixes: 5c578aedcb21d ("IPv6: convert addrconf hash list to RCU")
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Link: https://lore.kernel.org/r/8ab821e36073a4a406c50ec83c9e8dc586c539e4.1712585809.git.jbenc@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 11:32:19 +01:00
..
ila Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
netfilter netfilter: validate user input for expected length 2024-11-19 09:22:46 +01:00
addrconf.c ipv6: fix race condition between ipv6_get_ifaddr and ipv6_del_addr 2024-11-19 11:32:19 +01:00
addrconf_core.c ipv6: Ensure natural alignment of const ipv6 loopback and router addresses 2024-11-18 12:13:22 +01:00
addrlabel.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
af_inet6.c ipv6: init the accept_queue's spinlocks in inet6_create 2024-11-18 12:13:01 +01:00
ah6.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
anycast.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
calipso.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
datagram.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
esp6.c net: ipv6: fix return value check in esp_remove_trailer 2024-11-08 11:26:10 +01:00
esp6_offload.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
exthdrs.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
exthdrs_core.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
exthdrs_offload.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
fib6_notifier.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
fib6_rules.c ipv6: fib6_rules: flush route cache when rule is changed 2024-11-19 08:44:49 +01:00
fou6.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
icmp.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
inet6_connection_sock.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
inet6_hashtables.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ip6_checksum.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ip6_fib.c ipv6: fib: hide unused 'pn' variable 2024-11-19 11:32:19 +01:00
ip6_flowlabel.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ip6_gre.c erspan: make sure erspan_base_hdr is present in skb->head 2024-11-19 09:22:47 +01:00
ip6_icmp.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ip6_input.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ip6_offload.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ip6_offload.h Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ip6_output.c ipv6: avoid atomic fragment on GSO packets 2024-11-18 11:42:50 +01:00
ip6_tunnel.c Revert "ip6_tunnel: fix NEXTHDR_FRAGMENT handling in ip6_tnl_parse_tlv_enc_lim()" 2024-11-18 20:12:45 +01:00
ip6_udp_tunnel.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ip6_vti.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ip6mr.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ipcomp6.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ipv6_sockglue.c net/ipv4/ipv6: Replace one-element arraya with flexible-array members 2024-11-19 08:44:49 +01:00
Kconfig Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
Makefile Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
mcast.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
mcast_snoop.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
mip6.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ndisc.c net: change accept_ra_min_rtr_lft to affect all RA lifetimes 2024-11-08 11:25:47 +01:00
netfilter.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
output_core.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
ping.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
proc.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
protocol.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
raw.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
reassembly.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
route.c net/ipv6: avoid possible UAF in ip6_route_mpath_notify() 2024-11-18 23:19:34 +01:00
rpl.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
rpl_iptunnel.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
seg6.c ipv6: sr: fix possible use-after-free and null-ptr-deref 2024-11-18 22:25:41 +01:00
seg6_hmac.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
seg6_iptunnel.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
seg6_local.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
sit.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
syncookies.c dccp/tcp: Call security_inet_conn_request() after setting IPv6 addresses. 2024-11-18 11:43:07 +01:00
sysctl_net_ipv6.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
tcp_ipv6.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
tcpv6_offload.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
tunnel6.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
udp.c udp: do not accept non-tunnel GSO skbs landing in a tunnel 2024-11-19 09:22:49 +01:00
udp_impl.h Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
udp_offload.c udp: do not transition UDP GRO fraglist partial checksums to unnecessary 2024-11-19 09:22:47 +01:00
udplite.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
xfrm6_input.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
xfrm6_output.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
xfrm6_policy.c Revert "xfrm6: fix inet6_dev refcount underflow problem" 2024-11-17 19:38:30 +01:00
xfrm6_protocol.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
xfrm6_state.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00
xfrm6_tunnel.c Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00