Eric Dumazet c0a7416a54 net: memcg: fix lockdep splat in inet_csk_accept() ... commit 06669ea346 upstream. Locking newsk while still holding the listener lock triggered a lockdep splat [1] We can simply move the memcg code after we release the listener lock, as this can also help if multiple threads are sharing a common listener. Also fix a typo while reading socket sk_rmem_alloc. [1] WARNING: possible recursive locking detected 5.6.0-rc3-syzkaller #0 Not tainted -------------------------------------------- syz-executor598/9524 is trying to acquire lock: ffff88808b5b8b90 (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1541 [inline] ffff88808b5b8b90 (sk_lock-AF_INET6){+.+.}, at: inet_csk_accept+0x69f/0xd30 net/ipv4/inet_connection_sock.c:492 but task is already holding lock: ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1541 [inline] ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: inet_csk_accept+0x8d/0xd30 net/ipv4/inet_connection_sock.c:445 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sk_lock-AF_INET6); lock(sk_lock-AF_INET6); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by syz-executor598/9524: #0: ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: lock_sock include/net/sock.h:1541 [inline] #0: ffff88808b5b9590 (sk_lock-AF_INET6){+.+.}, at: inet_csk_accept+0x8d/0xd30 net/ipv4/inet_connection_sock.c:445 stack backtrace: CPU: 0 PID: 9524 Comm: syz-executor598 Not tainted 5.6.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x188/0x20d lib/dump_stack.c:118 print_deadlock_bug kernel/locking/lockdep.c:2370 [inline] check_deadlock kernel/locking/lockdep.c:2411 [inline] validate_chain kernel/locking/lockdep.c:2954 [inline] __lock_acquire.cold+0x114/0x288 kernel/locking/lockdep.c:3954 lock_acquire+0x197/0x420 kernel/locking/lockdep.c:4484 lock_sock_nested+0xc5/0x110 net/core/sock.c:2947 lock_sock include/net/sock.h:1541 [inline] inet_csk_accept+0x69f/0xd30 net/ipv4/inet_connection_sock.c:492 inet_accept+0xe9/0x7c0 net/ipv4/af_inet.c:734 __sys_accept4_file+0x3ac/0x5b0 net/socket.c:1758 __sys_accept4+0x53/0x90 net/socket.c:1809 __do_sys_accept4 net/socket.c:1821 [inline] __se_sys_accept4 net/socket.c:1818 [inline] __x64_sys_accept4+0x93/0xf0 net/socket.c:1818 do_syscall_64+0xf6/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4445c9 Code: e8 0c 0d 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffc35b37608 EFLAGS: 00000246 ORIG_RAX: 0000000000000120 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004445c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000306777 R09: 0000000000306777 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000004053d0 R14: 0000000000000000 R15: 0000000000000000 Fixes: d752a49865 ("net: memcg: late association of sock to memcg") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Shakeel Butt <shakeelb@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-03-18 07:17:43 +01:00
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bpfilter	…
netfilter	…
Kconfig	…
Makefile	…
af_inet.c	…
ah4.c	…
arp.c	…
cipso_ipv4.c	…
datagram.c	…
devinet.c	…
esp4.c	…
esp4_offload.c	…
fib_frontend.c	…
fib_lookup.h	…
fib_notifier.c	…
fib_rules.c	…
fib_semantics.c	…
fib_trie.c	…
fou.c	…
gre_demux.c	gre: fix uninit-value in __iptunnel_pull_header	2020-03-18 07:17:38 +01:00
gre_offload.c	…
icmp.c	…
igmp.c	…
inet_connection_sock.c	net: memcg: fix lockdep splat in inet_csk_accept()	2020-03-18 07:17:43 +01:00
inet_diag.c	inet_diag: return classid for all socket types	2020-03-18 07:17:38 +01:00
inet_fragment.c	…
inet_hashtables.c	…
inet_timewait_sock.c	…
inetpeer.c	…
ip_forward.c	…
ip_fragment.c	…
ip_gre.c	…
ip_input.c	…
ip_options.c	…
ip_output.c	…
ip_sockglue.c	…
ip_tunnel.c	…
ip_tunnel_core.c	…
ip_vti.c	vti[6]: fix packet tx through bpf_redirect()	2020-02-05 21:22:48 +00:00
ipcomp.c	…
ipconfig.c	…
ipip.c	…
ipmr.c	…
ipmr_base.c	…
metrics.c	…
netfilter.c	…
netlink.c	…
nexthop.c	net: include struct nhmsg size in nh nlmsg size	2020-02-01 09:34:39 +00:00
ping.c	…
proc.c	…
protocol.c	…
raw.c	…
raw_diag.c	inet_diag: return classid for all socket types	2020-03-18 07:17:38 +01:00
route.c	…
syncookies.c	…
sysctl_net_ipv4.c	…
tcp.c	tcp: clear tp->segs_{in|out} in tcp_disconnect()	2020-02-11 04:35:06 -08:00
tcp_bbr.c	…
tcp_bic.c	…
tcp_bpf.c	…
tcp_cdg.c	…
tcp_cong.c	…
tcp_cubic.c	…
tcp_dctcp.c	…
tcp_dctcp.h	…
tcp_diag.c	…
tcp_fastopen.c	…
tcp_highspeed.c	…
tcp_htcp.c	…
tcp_hybla.c	…
tcp_illinois.c	…
tcp_input.c	…
tcp_ipv4.c	…
tcp_lp.c	…
tcp_metrics.c	…
tcp_minisocks.c	…
tcp_nv.c	…
tcp_offload.c	…
tcp_output.c	…
tcp_rate.c	…
tcp_recovery.c	…
tcp_scalable.c	…
tcp_timer.c	…
tcp_ulp.c	…
tcp_vegas.c	…
tcp_vegas.h	…
tcp_veno.c	…
tcp_westwood.c	…
tcp_yeah.c	…
tunnel4.c	…
udp.c	udp: rehash on disconnect	2020-03-05 16:43:33 +01:00
udp_diag.c	inet_diag: return classid for all socket types	2020-03-18 07:17:38 +01:00
udp_impl.h	…
udp_offload.c	…
udp_tunnel.c	…
udplite.c	…
xfrm4_input.c	…
xfrm4_output.c	…
xfrm4_policy.c	…
xfrm4_protocol.c	…
xfrm4_state.c	…
xfrm4_tunnel.c	…