Taehee Yoo 71a8508402 net: bpfilter: disallow to remove bpfilter module while being used ... The bpfilter.ko module can be removed while functions of the bpfilter.ko are executing. so panic can occurred. in order to protect that, locks can be used. a bpfilter_lock protects routines in the __bpfilter_process_sockopt() but it's not enough because __exit routine can be executed concurrently. Now, the bpfilter_umh can not run in parallel. So, the module do not removed while it's being used and it do not double-create UMH process. The members of the umh_info and the bpfilter_umh_ops are protected by the bpfilter_umh_ops.lock. test commands: while : do iptables -I FORWARD -m string --string ap --algo kmp & modprobe -rv bpfilter & done splat looks like: [ 298.623435] BUG: unable to handle kernel paging request at fffffbfff807440b [ 298.628512] #PF error: [normal kernel read fault] [ 298.633018] PGD 124327067 P4D 124327067 PUD 11c1a3067 PMD 119eb2067 PTE 0 [ 298.638859] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI [ 298.638859] CPU: 0 PID: 2997 Comm: iptables Not tainted 4.20.0+ #154 [ 298.638859] RIP: 0010:__mutex_lock+0x6b9/0x16a0 [ 298.638859] Code: c0 00 00 e8 89 82 ff ff 80 bd 8f fc ff ff 00 0f 85 d9 05 00 00 48 8b 85 80 fc ff ff 48 bf 00 00 00 00 00 fc ff df 48 c1 e8 03 <80> 3c 38 00 0f 85 1d 0e 00 00 48 8b 85 c8 fc ff ff 49 39 47 58 c6 [ 298.638859] RSP: 0018:ffff88810e7777a0 EFLAGS: 00010202 [ 298.638859] RAX: 1ffffffff807440b RBX: ffff888111bd4d80 RCX: 0000000000000000 [ 298.638859] RDX: 1ffff110235ff806 RSI: ffff888111bd5538 RDI: dffffc0000000000 [ 298.638859] RBP: ffff88810e777b30 R08: 0000000080000002 R09: 0000000000000000 [ 298.638859] R10: 0000000000000000 R11: 0000000000000000 R12: fffffbfff168a42c [ 298.638859] R13: ffff888111bd4d80 R14: ffff8881040e9a05 R15: ffffffffc03a2000 [ 298.638859] FS: 00007f39e3758700(0000) GS:ffff88811ae00000(0000) knlGS:0000000000000000 [ 298.638859] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 298.638859] CR2: fffffbfff807440b CR3: 000000011243e000 CR4: 00000000001006f0 [ 298.638859] Call Trace: [ 298.638859] ? mutex_lock_io_nested+0x1560/0x1560 [ 298.638859] ? kasan_kmalloc+0xa0/0xd0 [ 298.638859] ? kmem_cache_alloc+0x1c2/0x260 [ 298.638859] ? __alloc_file+0x92/0x3c0 [ 298.638859] ? alloc_empty_file+0x43/0x120 [ 298.638859] ? alloc_file_pseudo+0x220/0x330 [ 298.638859] ? sock_alloc_file+0x39/0x160 [ 298.638859] ? __sys_socket+0x113/0x1d0 [ 298.638859] ? __x64_sys_socket+0x6f/0xb0 [ 298.638859] ? do_syscall_64+0x138/0x560 [ 298.638859] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 298.638859] ? __alloc_file+0x92/0x3c0 [ 298.638859] ? init_object+0x6b/0x80 [ 298.638859] ? cyc2ns_read_end+0x10/0x10 [ 298.638859] ? cyc2ns_read_end+0x10/0x10 [ 298.638859] ? hlock_class+0x140/0x140 [ 298.638859] ? sched_clock_local+0xd4/0x140 [ 298.638859] ? sched_clock_local+0xd4/0x140 [ 298.638859] ? check_flags.part.37+0x440/0x440 [ 298.638859] ? __lock_acquire+0x4f90/0x4f90 [ 298.638859] ? set_rq_offline.part.89+0x140/0x140 [ ... ] Fixes: d2ba09c17a ("net: add skeleton of bpfilter kernel module") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2019-01-11 18:05:41 -08:00
..
bpfilter	net: bpfilter: disallow to remove bpfilter module while being used	2019-01-11 18:05:41 -08:00
netfilter	Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next	2018-12-20 18:20:26 -08:00
af_inet.c	net: use indirect call wrappers at GRO transport layer	2018-12-15 13:23:02 -08:00
ah4.c	net-ipv4: remove 2 always zero parameters from ipv4_redirect()	2018-09-26 20:30:55 -07:00
arp.c	net: Evict neighbor entries on carrier down	2018-10-12 09:47:39 -07:00
cipso_ipv4.c	net/ipv4: defensive cipso option parsing	2018-09-17 19:37:46 -07:00
datagram.c	ipv4: Allow sending multicast packets on specific i/f using VRF socket	2018-10-02 22:28:17 -07:00
devinet.c	netlink: fixup regression in RTM_GETADDR	2019-01-04 12:47:06 -08:00
esp4_offload.c	net: use skb_sec_path helper in more places	2018-12-19 11:21:37 -08:00
esp4.c	net: use skb_sec_path helper in more places	2018-12-19 11:21:37 -08:00
fib_frontend.c	net: Don't return invalid table id error when dumping all families	2018-10-24 14:06:25 -07:00
fib_lookup.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
fib_notifier.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
fib_rules.c	ipv4: fib_rules: Fix possible infinite loop in fib_empty_table	2018-12-30 12:57:04 -08:00
fib_semantics.c	net: Add extack argument to ip_fib_metrics_init	2018-11-06 15:00:45 -08:00
fib_trie.c	net/ipv4: Plumb support for filtering route dumps	2018-10-16 00:13:12 -07:00
fou.c	fou: Prevent unbounded recursion in GUE error handler also with UDP-Lite	2019-01-04 13:06:07 -08:00
gre_demux.c	net: Convert protocol error handlers from void to int	2018-11-08 17:13:08 -08:00
gre_offload.c	Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net	2018-07-03 10:29:26 +09:00
icmp.c	net: Convert protocol error handlers from void to int	2018-11-08 17:13:08 -08:00
igmp.c	ipv4/igmp: fix v1/v2 switchback timeout based on rfc3376, 8.12	2018-10-29 20:26:06 -07:00
inet_connection_sock.c	inet: minor optimization for backlog setting in listen(2)	2018-11-07 22:31:07 -08:00
inet_diag.c	tcp: fix a race in inet_diag_dump_icsk()	2018-12-20 19:23:22 -08:00
inet_fragment.c	inet: frags: better deal with smp races	2018-11-08 18:40:30 -08:00
inet_hashtables.c	net: dccp: fix kernel crash on module load	2018-12-24 15:27:56 -08:00
inet_timewait_sock.c	soreuseport: initialise timewait reuseport field	2018-04-07 22:32:32 -04:00
inetpeer.c	inetpeer: fix uninit-value in inet_getpeer	2018-04-09 10:57:35 -04:00
ip_forward.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2018-12-20 11:53:36 -08:00
ip_fragment.c	net: ipv4: do not handle duplicate fragments as overlapping	2018-12-15 11:50:40 -08:00
ip_gre.c	ip: validate header length on virtual device xmit	2019-01-01 12:05:02 -08:00
ip_input.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2018-12-09 21:43:31 -08:00
ip_options.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
ip_output.c	sk_buff: add skb extension infrastructure	2018-12-19 11:21:37 -08:00
ip_sockglue.c	ip: on queued skb use skb_header_pointer instead of pskb_may_pull	2019-01-10 09:27:20 -05:00
ip_tunnel_core.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2018-12-24 16:19:56 -08:00
ip_tunnel.c	ip: validate header length on virtual device xmit	2019-01-01 12:05:02 -08:00
ip_vti.c	ip: validate header length on virtual device xmit	2019-01-01 12:05:02 -08:00
ipcomp.c	net-ipv4: remove 2 always zero parameters from ipv4_redirect()	2018-09-26 20:30:55 -07:00
ipconfig.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2018-12-20 11:53:36 -08:00
ipip.c	net: Convert protocol error handlers from void to int	2018-11-08 17:13:08 -08:00
ipmr_base.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2018-10-19 11:03:06 -07:00
ipmr.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2018-12-20 11:53:36 -08:00
Kconfig	net: remove blank lines at end of file	2018-07-24 14:10:43 -07:00
Makefile	bpf, sockmap: convert to generic sk_msg interface	2018-10-15 12:23:19 -07:00
metrics.c	net: Add extack argument to ip_fib_metrics_init	2018-11-06 15:00:45 -08:00
netfilter.c	netfilter: utils: move nf_ip_checksum* from ipv4 to utils	2018-07-16 17:51:48 +02:00
netlink.c	ipv4: support sport, dport and ip_proto in RTM_GETROUTE	2018-05-23 15:14:12 -04:00
ping.c	ipv4: Allow sending multicast packets on specific i/f using VRF socket	2018-10-02 22:28:17 -07:00
proc.c	tcp: implement coalescing on backlog queue	2018-11-30 13:26:54 -08:00
protocol.c	fou, fou6: ICMP error handlers for FoU and GUE	2018-11-08 17:13:08 -08:00
raw_diag.c	net: ipv6: add second dif to raw socket lookups	2017-08-07 11:39:22 -07:00
raw.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2018-12-20 11:53:36 -08:00
route.c	net: ipv4: Set skb->dev for output route resolution	2018-12-20 16:42:39 -08:00
syncookies.c	tcp: provide earliest departure time in skb->tstamp	2018-09-21 19:37:59 -07:00
sysctl_net_ipv4.c	net: provide a sysctl raw_l3mdev_accept for raw socket lookup with VRFs	2018-11-07 16:12:38 -08:00
tcp_bbr.c	tcp_bbr: update comments to reflect pacing_margin_percent	2018-11-08 20:46:17 -08:00
tcp_bic.c	tcp: consolidate congestion control undo functions	2017-08-06 21:25:10 -07:00
tcp_bpf.c	bpf: sk_msg, sock{map|hash} redirect through ULP	2018-12-20 23:47:09 +01:00
tcp_cdg.c	tcp: cdg: use tcp high resolution clock cache	2018-10-15 22:56:42 -07:00
tcp_cong.c	tcp: Namespace-ify sysctl_tcp_default_congestion_control	2017-11-15 14:09:52 +09:00
tcp_cubic.c	tcp: consolidate congestion control undo functions	2017-08-06 21:25:10 -07:00
tcp_dctcp.c	tcp: refactor DCTCP ECN ACK handling	2018-10-10 22:26:00 -07:00
tcp_dctcp.h	tcp: refactor DCTCP ECN ACK handling	2018-10-10 22:26:00 -07:00
tcp_diag.c	net: sock: replace sk_state_load with inet_sk_state_load and remove sk_state_store	2017-12-20 14:00:25 -05:00
tcp_fastopen.c	tcp: pause Fast Open globally after third consecutive timeout	2017-12-13 15:51:12 -05:00
tcp_highspeed.c	tcp: consolidate congestion control undo functions	2017-08-06 21:25:10 -07:00
tcp_htcp.c	tcp: fix cwnd undo in Reno and HTCP congestion controls	2017-08-06 21:25:10 -07:00
tcp_hybla.c
tcp_illinois.c	net/tcp/illinois: replace broken algorithm reference link	2018-02-28 12:03:47 -05:00
tcp_input.c	tcp: take care of compressed acks in tcp_add_reno_sack()	2018-11-30 13:26:53 -08:00
tcp_ipv4.c	tcp: md5: add tcp_md5_needed jump label	2018-11-30 13:28:03 -08:00
tcp_lp.c
tcp_metrics.c	mm: convert totalram_pages and totalhigh_pages variables to atomic	2018-12-28 12:11:47 -08:00
tcp_minisocks.c	tcp: do not restart timewait timer on rst reception	2018-08-31 23:10:35 -07:00
tcp_nv.c	tcp_nv: fix potential integer overflow in tcpnv_acked	2018-01-31 10:26:30 -05:00
tcp_offload.c	net: use indirect call wrappers at GRO transport layer	2018-12-15 13:23:02 -08:00
tcp_output.c	tcp: handle EOR and FIN conditions the same in tcp_tso_should_defer()	2018-12-10 12:09:15 -08:00
tcp_rate.c	tcp: introduce tcp_skb_timestamp_us() helper	2018-09-21 19:37:59 -07:00
tcp_recovery.c	tcp: introduce tcp_skb_timestamp_us() helper	2018-09-21 19:37:59 -07:00
tcp_scalable.c	tcp: consolidate congestion control undo functions	2017-08-06 21:25:10 -07:00
tcp_timer.c	tcp: change txhash on SYN-data timeout	2019-01-10 16:55:41 -05:00
tcp_ulp.c	tcp, ulp: remove socket lock assertion on ULP cleanup	2018-10-16 12:38:41 -07:00
tcp_vegas.c	tcp: fix under-evaluated ssthresh in TCP Vegas	2017-09-29 06:07:00 +01:00
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: consolidate congestion control undo functions	2017-08-06 21:25:10 -07:00
tcp_westwood.c	tcp: Revert "tcp: remove CA_ACK_SLOWPATH"	2017-08-30 11:20:08 -07:00
tcp_yeah.c	tcp: consolidate congestion control undo functions	2017-08-06 21:25:10 -07:00
tcp.c	tcp: fix code style in tcp_recvmsg()	2018-12-06 12:19:47 -08:00
tunnel4.c	net: Convert protocol error handlers from void to int	2018-11-08 17:13:08 -08:00
udp_diag.c	net: diag: document swapped src/dst in udp_dump_one.	2018-10-28 19:27:21 -07:00
udp_impl.h	net: Convert protocol error handlers from void to int	2018-11-08 17:13:08 -08:00
udp_offload.c	udp: use indirect call wrappers for GRO socket lookup	2018-12-15 13:23:02 -08:00
udp_tunnel.c	udp_tunnel: add config option to bind to a device	2018-12-03 14:15:26 -08:00
udp.c	net: udp: prefer listeners bound to an address	2018-12-14 15:55:20 -08:00
udplite.c	net: Convert protocol error handlers from void to int	2018-11-08 17:13:08 -08:00
xfrm4_input.c	xfrm: reset transport header back to network header after all input transforms ahave been applied	2018-09-04 10:26:30 +02:00
xfrm4_mode_beet.c
xfrm4_mode_transport.c	xfrm: reset transport header back to network header after all input transforms ahave been applied	2018-09-04 10:26:30 +02:00
xfrm4_mode_tunnel.c	xfrm: Verify MAC header exists before overwriting eth_hdr(skb)->h_proto	2018-03-07 10:54:29 +01:00
xfrm4_output.c	net: xfrm: use skb_gso_validate_network_len() to check gso sizes	2018-03-04 17:49:17 -05:00
xfrm4_policy.c	net: Drop pernet_operations::async	2018-03-27 13:18:09 -04:00
xfrm4_protocol.c	net: Convert protocol error handlers from void to int	2018-11-08 17:13:08 -08:00
xfrm4_state.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
xfrm4_tunnel.c