linux/net/sctp
Xin Long 312434617c sctp: cache netns in sctp_ep_common
This patch is to fix a data-race reported by syzbot:

  BUG: KCSAN: data-race in sctp_assoc_migrate / sctp_hash_obj

  write to 0xffff8880b67c0020 of 8 bytes by task 18908 on cpu 1:
    sctp_assoc_migrate+0x1a6/0x290 net/sctp/associola.c:1091
    sctp_sock_migrate+0x8aa/0x9b0 net/sctp/socket.c:9465
    sctp_accept+0x3c8/0x470 net/sctp/socket.c:4916
    inet_accept+0x7f/0x360 net/ipv4/af_inet.c:734
    __sys_accept4+0x224/0x430 net/socket.c:1754
    __do_sys_accept net/socket.c:1795 [inline]
    __se_sys_accept net/socket.c:1792 [inline]
    __x64_sys_accept+0x4e/0x60 net/socket.c:1792
    do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
    entry_SYSCALL_64_after_hwframe+0x44/0xa9

  read to 0xffff8880b67c0020 of 8 bytes by task 12003 on cpu 0:
    sctp_hash_obj+0x4f/0x2d0 net/sctp/input.c:894
    rht_key_get_hash include/linux/rhashtable.h:133 [inline]
    rht_key_hashfn include/linux/rhashtable.h:159 [inline]
    rht_head_hashfn include/linux/rhashtable.h:174 [inline]
    head_hashfn lib/rhashtable.c:41 [inline]
    rhashtable_rehash_one lib/rhashtable.c:245 [inline]
    rhashtable_rehash_chain lib/rhashtable.c:276 [inline]
    rhashtable_rehash_table lib/rhashtable.c:316 [inline]
    rht_deferred_worker+0x468/0xab0 lib/rhashtable.c:420
    process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
    worker_thread+0xa0/0x800 kernel/workqueue.c:2415
    kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
    ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

It was caused by rhashtable access asoc->base.sk when sctp_assoc_migrate
is changing its value. However, what rhashtable wants is netns from asoc
base.sk, and for an asoc, its netns won't change once set. So we can
simply fix it by caching netns since created.

Fixes: d6c0256a60 ("sctp: add the rhashtable apis for sctp global transport hashtable")
Reported-by: syzbot+e3b35fe7918ff0ee474e@syzkaller.appspotmail.com
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-11-23 18:26:14 -08:00
..
associola.c sctp: cache netns in sctp_ep_common 2019-11-23 18:26:14 -08:00
auth.c sctp: add sctp_auth_init and sctp_auth_free 2019-08-19 18:27:29 -07:00
bind_addr.c sctp: remove rcu_read_lock from sctp_bind_addr_state 2019-07-08 20:18:11 -07:00
chunk.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
debug.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
diag.c net: silence KCSAN warnings about sk->sk_backlog.len reads 2019-10-09 21:43:00 -07:00
endpointola.c sctp: cache netns in sctp_ep_common 2019-11-23 18:26:14 -08:00
input.c sctp: cache netns in sctp_ep_common 2019-11-23 18:26:14 -08:00
inqueue.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
ipv6.c ipv6: add priority parameter to ip6_xmit() 2019-09-27 12:05:02 +02:00
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile sctp: rename sctp_diag.c as diag.c 2018-02-13 13:56:31 -05:00
objcnt.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
offload.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-07 11:00:14 -07:00
output.c sctp: count data bundling sack chunk for outctrlchunks 2019-07-03 11:41:24 -07:00
outqueue.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
primitive.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
proc.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
protocol.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-09-15 14:17:27 +02:00
sm_make_chunk.c net: sctp: Rename fallthrough label to unhandled 2019-10-11 09:26:05 -07:00
sm_sideeffect.c sctp: use transport pf_retrans in sctp_do_8_2_transport_strike 2019-09-05 00:29:21 +02:00
sm_statefuns.c sctp: Fix memory leak in sctp_sf_do_5_2_4_dupcook 2019-11-23 18:20:17 -08:00
sm_statetable.c sctp: remove net sctp.x_enable working as a global switch 2019-08-19 18:27:29 -07:00
socket.c inet: stop leaking jiffies on the wire 2019-11-01 14:57:52 -07:00
stream_interleave.c sctp: rename asoc intl_enable to asoc peer.intl_capable 2019-07-08 20:16:25 -07:00
stream_sched_prio.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
stream_sched_rr.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
stream_sched.c sctp: rename asoc intl_enable to asoc peer.intl_capable 2019-07-08 20:16:25 -07:00
stream.c sctp: fix memleak in sctp_send_reset_streams 2019-08-13 20:45:01 -07:00
sysctl.c sctp: allow users to set netns ecn flag with sysctl 2019-08-27 20:54:14 -07:00
transport.c sctp: only copy the available addr data in sctp_transport_init 2019-07-30 14:18:14 -07:00
tsnmap.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
ulpevent.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
ulpqueue.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00