linux/net
Davide Caratti 62931f59ce ipvs: don't ignore errors in case refcounting ip_vs module fails
if the IPVS module is removed while the sync daemon is starting, there is
a small gap where try_module_get() might fail getting the refcount inside
ip_vs_use_count_inc(). Then, the refcounts of IPVS module are unbalanced,
and the subsequent call to stop_sync_thread() causes the following splat:

 WARNING: CPU: 0 PID: 4013 at kernel/module.c:1146 module_put.part.44+0x15b/0x290
  Modules linked in: ip_vs(-) nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 veth ip6table_filter ip6_tables iptable_filter binfmt_misc intel_rapl_msr intel_rapl_common crct10dif_pclmul crc32_pclmul ext4 mbcache jbd2 ghash_clmulni_intel snd_hda_codec_generic ledtrig_audio snd_hda_intel snd_intel_nhlt snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm aesni_intel crypto_simd cryptd glue_helper joydev pcspkr snd_timer virtio_balloon snd soundcore i2c_piix4 nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c ata_generic pata_acpi virtio_net net_failover virtio_blk failover virtio_console qxl drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ata_piix ttm crc32c_intel serio_raw drm virtio_pci libata virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod [last unloaded: nf_defrag_ipv6]
  CPU: 0 PID: 4013 Comm: modprobe Tainted: G        W         5.4.0-rc1.upstream+ #741
  Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
  RIP: 0010:module_put.part.44+0x15b/0x290
  Code: 04 25 28 00 00 00 0f 85 18 01 00 00 48 83 c4 68 5b 5d 41 5c 41 5d 41 5e 41 5f c3 89 44 24 28 83 e8 01 89 c5 0f 89 57 ff ff ff <0f> 0b e9 78 ff ff ff 65 8b 1d 67 83 26 4a 89 db be 08 00 00 00 48
  RSP: 0018:ffff888050607c78 EFLAGS: 00010297
  RAX: 0000000000000003 RBX: ffffffffc1420590 RCX: ffffffffb5db0ef9
  RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffffc1420590
  RBP: 00000000ffffffff R08: fffffbfff82840b3 R09: fffffbfff82840b3
  R10: 0000000000000001 R11: fffffbfff82840b2 R12: 1ffff1100a0c0f90
  R13: ffffffffc1420200 R14: ffff88804f533300 R15: ffff88804f533ca0
  FS:  00007f8ea9720740(0000) GS:ffff888053800000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f3245abe000 CR3: 000000004c28a006 CR4: 00000000001606f0
  Call Trace:
   stop_sync_thread+0x3a3/0x7c0 [ip_vs]
   ip_vs_sync_net_cleanup+0x13/0x50 [ip_vs]
   ops_exit_list.isra.5+0x94/0x140
   unregister_pernet_operations+0x29d/0x460
   unregister_pernet_device+0x26/0x60
   ip_vs_cleanup+0x11/0x38 [ip_vs]
   __x64_sys_delete_module+0x2d5/0x400
   do_syscall_64+0xa5/0x4e0
   entry_SYSCALL_64_after_hwframe+0x49/0xbe
  RIP: 0033:0x7f8ea8bf0db7
  Code: 73 01 c3 48 8b 0d b9 80 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 b0 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 89 80 2c 00 f7 d8 64 89 01 48
  RSP: 002b:00007ffcd38d2fe8 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
  RAX: ffffffffffffffda RBX: 0000000002436240 RCX: 00007f8ea8bf0db7
  RDX: 0000000000000000 RSI: 0000000000000800 RDI: 00000000024362a8
  RBP: 0000000000000000 R08: 00007f8ea8eba060 R09: 00007f8ea8c658a0
  R10: 00007ffcd38d2a60 R11: 0000000000000206 R12: 0000000000000000
  R13: 0000000000000001 R14: 00000000024362a8 R15: 0000000000000000
  irq event stamp: 4538
  hardirqs last  enabled at (4537): [<ffffffffb6193dde>] quarantine_put+0x9e/0x170
  hardirqs last disabled at (4538): [<ffffffffb5a0556a>] trace_hardirqs_off_thunk+0x1a/0x20
  softirqs last  enabled at (4522): [<ffffffffb6f8ebe9>] sk_common_release+0x169/0x2d0
  softirqs last disabled at (4520): [<ffffffffb6f8eb3e>] sk_common_release+0xbe/0x2d0

Check the return value of ip_vs_use_count_inc() and let its caller return
proper error. Inside do_ip_vs_set_ctl() the module is already refcounted,
we don't need refcount/derefcount there. Finally, in register_ip_vs_app()
and start_sync_thread(), take the module refcount earlier and ensure it's
released in the error path.

Change since v1:
 - better return values in case of failure of ip_vs_use_count_inc(),
   thanks to Julian Anastasov
 - no need to increase/decrease the module refcount in ip_vs_set_ctl(),
   thanks to Julian Anastasov

Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
2019-10-24 11:53:19 +02:00
..
6lowpan 6lowpan: no need to check return value of debugfs_create functions 2019-07-06 12:50:01 +02:00
9p 9p pull request for inclusion in 5.4 2019-09-27 15:10:34 -07:00
802 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
8021q Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-22 08:59:24 -04:00
appletalk appletalk: enforce CAP_NET_RAW for raw sockets 2019-09-24 16:37:18 +02:00
atm pppoatm: use %*ph to print small buffer 2019-09-05 12:33:28 +02:00
ax25 ax25: enforce CAP_NET_RAW for raw sockets 2019-09-24 16:37:18 +02:00
batman-adv netfilter: drop bridge nf reset from nf_reset 2019-10-01 18:42:15 +02:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2019-09-18 12:34:53 -07:00
bpf bpf/flow_dissector: support flags in BPF_PROG_TEST_RUN 2019-07-25 18:00:41 -07:00
bpfilter Kbuild updates for v5.3 2019-07-12 16:03:16 -07:00
bridge ipv4: fix IPSKB_FRAG_PMTU handling with fragmentation 2019-10-21 10:46:42 -07:00
caif treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 194 2019-05-30 11:29:22 -07:00
can can: add support of SAE J1939 protocol 2019-09-04 14:22:33 +02:00
ceph libceph: use ceph_kvmalloc() for osdmap arrays 2019-09-16 12:06:25 +02:00
core net/sched: fix corrupted L2 header with MPLS 'push' and 'pop' actions 2019-10-15 17:14:48 -07:00
dcb treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201 2019-05-30 11:29:52 -07:00
dccp netfilter: drop bridge nf reset from nf_reset 2019-10-01 18:42:15 +02:00
decnet
dns_resolver Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs" 2019-07-10 18:43:43 -07:00
dsa net: dsa: fix switch tree list 2019-10-19 12:19:41 -07:00
ethernet Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-07 11:00:14 -07:00
hsr hsr: switch ->dellink() to ->ndo_uninit() 2019-07-11 14:37:45 -07:00
ieee802154 ieee802154: enforce CAP_NET_RAW for raw sockets 2019-09-24 16:37:18 +02:00
ife net: Fix Kconfig indentation 2019-09-26 08:56:17 +02:00
ipv4 ipv4: fix IPSKB_FRAG_PMTU handling with fragmentation 2019-10-21 10:46:42 -07:00
ipv6 ipv6: include <net/addrconf.h> for missing declarations 2019-10-22 15:17:03 -07:00
iucv net/af_iucv: mark expected switch fall-throughs 2019-07-29 10:26:14 -07:00
kcm kcm: disable preemption in kcm_parse_func_strparser() 2019-09-27 10:27:14 +02:00
key Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-07-08 19:48:57 -07:00
l2tp netfilter: drop bridge nf reset from nf_reset 2019-10-01 18:42:15 +02:00
l3mdev ipv6: convert major tx path to use RT6_LOOKUP_F_DST_NOREF 2019-06-23 13:24:17 -07:00
lapb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-17 20:20:36 -07:00
llc net: silence KCSAN warnings around sk_add_backlog() calls 2019-10-09 21:42:59 -07:00
mac80211 mac80211: fix scan when operating on DFS channels in ETSI domains 2019-10-07 22:10:50 +02:00
mac802154 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174 2019-05-30 11:26:41 -07:00
mpls ipv4: mpls: fix mpls_xmit for iptunnel 2019-08-25 14:34:08 -07:00
ncsi net/ncsi: Disable global multicast filter 2019-09-19 18:04:40 -07:00
netfilter ipvs: don't ignore errors in case refcounting ip_vs module fails 2019-10-24 11:53:19 +02:00
netlabel netlabel: remove redundant assignment to pointer iter 2019-09-01 11:45:02 -07:00
netlink net: remove empty netlink_tap_exit_net 2019-06-14 19:50:33 -07:00
netrom netrom: hold sock when setting skb->destructor 2019-07-24 15:49:05 -07:00
nfc nfc: fix memory leak in llcp_sock_bind() 2019-10-04 18:31:36 -07:00
nsh treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
openvswitch net: openvswitch: free vport unless register_netdevice() succeeds 2019-10-22 14:45:08 -07:00
packet netfilter: drop bridge nf reset from nf_reset 2019-10-01 18:42:15 +02:00
phonet treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 336 2019-06-05 17:37:07 +02:00
psample net: sched: take reference to psample group in flow_action infra 2019-09-16 09:18:03 +02:00
qrtr net: qrtr: Stop rx_worker before freeing node 2019-09-21 18:45:46 -07:00
rds net/rds: Fix error handling in rds_ib_add_one() 2019-10-02 12:16:57 -04:00
rfkill treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
rose treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
rxrpc rxrpc: use rcu protection while reading sk->sk_user_data 2019-10-16 12:20:17 -07:00
sched net: sched: taprio: fix -Wmissing-prototypes warnings 2019-10-22 13:35:07 -07:00
sctp Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-10-19 17:09:11 -04:00
smc net/smc: receive pending data after RCV_SHUTDOWN 2019-10-10 19:08:41 -07:00
strparser Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-22 08:59:24 -04:00
sunrpc SUNRPC: fix race to sk_err after xs_error_report 2019-10-10 16:14:28 -04:00
switchdev treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
tipc net: silence KCSAN warnings about sk->sk_backlog.len reads 2019-10-09 21:43:00 -07:00
tls net/tls: align non temporal copy to cache lines 2019-09-07 18:10:34 +02:00
unix Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-07 11:00:14 -07:00
vmw_vsock vsock/virtio: discard packets if credit is not respected 2019-10-18 10:19:43 -07:00
wimax wimax: no need to check return value of debugfs_create functions 2019-08-10 15:25:47 -07:00
wireless mac80211: fix scan when operating on DFS channels in ETSI domains 2019-10-07 22:10:50 +02:00
x25 net: silence KCSAN warnings around sk_add_backlog() calls 2019-10-09 21:42:59 -07:00
xdp xsk: Fix crash in poll when device does not support ndo_xsk_wakeup 2019-10-03 16:34:27 +02:00
xfrm netfilter: drop bridge nf reset from nf_reset 2019-10-01 18:42:15 +02:00
Kconfig devlink: Add packet trap infrastructure 2019-08-17 12:40:08 -07:00
Makefile
compat.c uio: make import_iovec()/compat_import_iovec() return bytes on success 2019-05-31 15:30:03 -06:00
socket.c Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
sysctl_net.c