linux/net/core
Eric Dumazet a443c55d96 bpf, sockmap: fix race in sock_map_free()
[ Upstream commit 0a182f8d60 ]

sock_map_free() calls release_sock(sk) without owning a reference
on the socket. This can cause use-after-free as syzbot found [1]

Jakub Sitnicki already took care of a similar issue
in sock_hash_free() in commit 75e68e5bf2 ("bpf, sockhash:
Synchronize delete from bucket list on map free")

[1]
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 0 PID: 3785 at lib/refcount.c:31 refcount_warn_saturate+0x17c/0x1a0 lib/refcount.c:31
Modules linked in:
CPU: 0 PID: 3785 Comm: kworker/u4:6 Not tainted 6.1.0-rc7-syzkaller-00103-gef4d3ea40565 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Workqueue: events_unbound bpf_map_free_deferred
RIP: 0010:refcount_warn_saturate+0x17c/0x1a0 lib/refcount.c:31
Code: 68 8b 31 c0 e8 75 71 15 fd 0f 0b e9 64 ff ff ff e8 d9 6e 4e fd c6 05 62 9c 3d 0a 01 48 c7 c7 80 bb 68 8b 31 c0 e8 54 71 15 fd <0f> 0b e9 43 ff ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c a2 fe ff
RSP: 0018:ffffc9000456fb60 EFLAGS: 00010246
RAX: eae59bab72dcd700 RBX: 0000000000000004 RCX: ffff8880207057c0
RDX: 0000000000000000 RSI: 0000000000000201 RDI: 0000000000000000
RBP: 0000000000000004 R08: ffffffff816fdabd R09: fffff520008adee5
R10: fffff520008adee5 R11: 1ffff920008adee4 R12: 0000000000000004
R13: dffffc0000000000 R14: ffff88807b1c6c00 R15: 1ffff1100f638dcf
FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30c30000 CR3: 000000000d08e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__refcount_dec include/linux/refcount.h:344 [inline]
refcount_dec include/linux/refcount.h:359 [inline]
__sock_put include/net/sock.h:779 [inline]
tcp_release_cb+0x2d0/0x360 net/ipv4/tcp_output.c:1092
release_sock+0xaf/0x1c0 net/core/sock.c:3468
sock_map_free+0x219/0x2c0 net/core/sock_map.c:356
process_one_work+0x81c/0xd10 kernel/workqueue.c:2289
worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
kthread+0x266/0x300 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>

Fixes: 7e81a35302 ("bpf: Sockmap, ensure sock lock held during tear down")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Jakub Sitnicki <jakub@cloudflare.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Song Liu <songliubraving@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20221202111640.2745533-1-edumazet@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2022-12-31 13:14:16 +01:00
..
bpf_sk_storage.c net: Fix data-races around sysctl_optmem_max. 2022-08-31 17:16:43 +02:00
datagram.c tcp: TX zerocopy should not sense pfmemalloc status 2022-09-15 11:30:05 +02:00
datagram.h net/core: Allow the compiler to verify declaration and definition consistency 2019-03-27 13:49:44 -07:00
dev.c bpf: Don't redirect packets with invalid pkt_len 2022-09-05 10:30:07 +02:00
dev_addr_lists.c net: dev_addr_list: handle first address in __hw_addr_add_ex 2021-09-30 13:29:09 +01:00
dev_ioctl.c net: core: don't call SIOCBRADD/DELIF for non-bridge devices 2021-08-05 11:36:59 +01:00
devlink.c devlink: Fix use-after-free after a failed reload 2022-08-25 11:40:06 +02:00
drop_monitor.c net: skb: introduce kfree_skb_reason() 2022-07-29 17:25:15 +02:00
dst.c net: Remove redundant if statements 2021-08-05 13:27:50 +01:00
dst_cache.c wireguard: device: reset peer src endpoint when netns exits 2021-12-08 09:04:46 +01:00
failover.c failover: allow name change on IFF_UP slave interfaces 2019-04-10 22:12:26 -07:00
fib_notifier.c net: fib_notifier: propagate extack down to the notifier block callback 2019-10-04 11:10:56 -07:00
fib_rules.c ipv6: fix memory leak in fib6_rule_suppress 2021-12-08 09:04:43 +01:00
filter.c bpf: Move skb->len == 0 checks into __bpf_redirect 2022-12-31 13:14:11 +01:00
flow_dissector.c netfilter: conntrack: Fix data-races around ct mark 2022-12-02 17:41:04 +01:00
flow_offload.c netfilter: nf_tables: bail out early if hardware offload is not supported 2022-06-14 18:36:17 +02:00
gen_estimator.c net_sched: gen_estimator: support large ewma log 2021-01-15 18:11:06 -08:00
gen_stats.c docs: networking: convert gen_stats.txt to ReST 2020-04-28 14:39:46 -07:00
gro_cells.c net: Fix data-races around netdev_max_backlog. 2022-08-31 17:16:42 +02:00
hwbm.c net: hwbm: Make the hwbm_pool lock a mutex 2019-06-09 19:40:10 -07:00
link_watch.c net: Write lock dev_base_lock without disabling bottom halves. 2022-06-29 09:03:22 +02:00
lwt_bpf.c bpf, lwt: Fix crash when using bpf_skb_set_tunnel_key() from bpf_xmit lwt hook 2022-05-09 09:14:35 +02:00
lwtunnel.c lwtunnel: Validate RTA_ENCAP_TYPE attribute length 2022-01-11 15:35:14 +01:00
Makefile of: net: move of_net under net/ 2022-03-08 19:12:41 +01:00
neighbour.c net, neigh: Fix null-ptr-deref in neigh_table_clear() 2022-11-10 18:15:31 +01:00
net-procfs.c net-procfs: show net devices bound packet types 2022-02-01 17:27:08 +01:00
net-sysfs.c net: fix data-race in dev_isalive() 2022-06-29 09:03:22 +02:00
net-sysfs.h net-sysfs: add netdev_change_owner() 2020-02-26 20:07:25 -08:00
net-traces.c tcp: add tracepoint for checksum errors 2021-05-14 15:26:03 -07:00
net_namespace.c net: fix UAF issue in nfqnl_nf_hook_drop() when ops_init() failed 2022-11-03 23:59:16 +09:00
netclassid_cgroup.c bpf, cgroups: Fix cgroup v2 fallback on v1/v2 mixed mode 2021-09-13 16:35:58 -07:00
netevent.c net: core: Correct function name netevent_unregister_notifier() in the kerneldoc 2021-03-28 17:56:56 -07:00
netpoll.c asm-generic/unaligned: Unify asm/unaligned.h around struct helper 2021-07-02 12:43:40 -07:00
netprio_cgroup.c bpf, cgroups: Fix cgroup v2 fallback on v1/v2 mixed mode 2021-09-13 16:35:58 -07:00
of_net.c of: net: move of_net under net/ 2022-03-08 19:12:41 +01:00
page_pool.c page_pool: use relaxed atomic for release side accounting 2021-08-24 10:46:31 +01:00
pktgen.c pktgen: remove unused variable 2021-09-03 11:48:28 +01:00
ptp_classifier.c bpf: Refactor BPF_PROG_RUN into a function 2021-08-17 00:45:07 +02:00
request_sock.c tcp: add rcu protection around tp->fastopen_rsk 2019-10-13 10:13:08 -07:00
rtnetlink.c net: Write lock dev_base_lock without disabling bottom halves. 2022-06-29 09:03:22 +02:00
scm.c memcg: enable accounting for scm_fp_list objects 2021-07-20 06:00:38 -07:00
secure_seq.c tcp: Fix data-races around sysctl knobs related to SYN option. 2022-07-29 17:25:22 +02:00
selftests.c net: selftests: add MTU test 2021-07-22 00:52:04 -07:00
skbuff.c net: gso: fix panic on frag_list with mixed head alloc types 2022-11-16 09:58:16 +01:00
skmsg.c bpf, sockmap: Fix missing BPF_F_INGRESS flag when using apply_bytes 2022-12-31 13:14:14 +01:00
sock.c soreuseport: Fix socket selection for SO_INCOMING_CPU. 2022-12-31 13:14:07 +01:00
sock_destructor.h skb_expand_head() adjust skb->truesize incorrectly 2021-10-22 12:35:51 -07:00
sock_diag.c bpf, net: Rework cookie generator as per-cpu one 2020-09-30 11:50:35 -07:00
sock_map.c bpf, sockmap: fix race in sock_map_free() 2022-12-31 13:14:16 +01:00
sock_reuseport.c soreuseport: Fix socket selection for SO_INCOMING_CPU. 2022-12-31 13:14:07 +01:00
stream.c net: If sock is dead don't access sock's sk_wq in sk_stream_wait_memory 2022-10-26 12:35:37 +02:00
sysctl_net_core.c net: Fix data-races around weight_p and dev_weight_[rt]x_bias. 2022-08-31 17:16:42 +02:00
timestamping.c net: Introduce a new MII time stamping interface. 2019-12-25 19:51:33 -08:00
tso.c net: tso: add UDP segmentation support 2020-06-18 20:46:23 -07:00
utils.c net: Fix skb->csum update in inet_proto_csum_replace16(). 2020-01-24 20:54:30 +01:00
xdp.c xdp: Move the rxq_info.mem clearing to unreg_mem_model() 2021-06-28 23:07:59 +02:00