linux/net
Eric Dumazet 39f13ea2f6 net: avoid potential infinite loop in tc_ctl_action()
tc_ctl_action() has the ability to loop forever if tcf_action_add()
returns -EAGAIN.

This special case has been done in case a module needed to be loaded,
but it turns out that tcf_add_notify() could also return -EAGAIN
if the socket sk_rcvbuf limit is hit.

We need to separate the two cases, and only loop for the module
loading case.

While we are at it, add a limit of 10 attempts since unbounded
loops are always scary.

syzbot repro was something like :

socket(PF_NETLINK, SOCK_RAW|SOCK_NONBLOCK, NETLINK_ROUTE) = 3
write(3, ..., 38) = 38
setsockopt(3, SOL_SOCKET, SO_RCVBUF, [0], 4) = 0
sendmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{..., 388}], msg_controllen=0, msg_flags=0x10}, ...)

NMI backtrace for cpu 0
CPU: 0 PID: 1054 Comm: khungtaskd Not tainted 5.4.0-rc1+ #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+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline]
 watchdog+0x9d0/0xef0 kernel/hung_task.c:289
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8859 Comm: syz-executor910 Not tainted 5.4.0-rc1+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:arch_local_save_flags arch/x86/include/asm/paravirt.h:751 [inline]
RIP: 0010:lockdep_hardirqs_off+0x1df/0x2e0 kernel/locking/lockdep.c:3453
Code: 5c 08 00 00 5b 41 5c 41 5d 5d c3 48 c7 c0 58 1d f3 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 d3 00 00 00 <48> 83 3d 21 9e 99 07 00 0f 84 b9 00 00 00 9c 58 0f 1f 44 00 00 f6
RSP: 0018:ffff8880a6f3f1b8 EFLAGS: 00000046
RAX: 1ffffffff11e63ab RBX: ffff88808c9c6080 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff88808c9c6914
RBP: ffff8880a6f3f1d0 R08: ffff88808c9c6080 R09: fffffbfff16be5d1
R10: fffffbfff16be5d0 R11: 0000000000000003 R12: ffffffff8746591f
R13: ffff88808c9c6080 R14: ffffffff8746591f R15: 0000000000000003
FS:  00000000011e4880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 00000000a8920000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 trace_hardirqs_off+0x62/0x240 kernel/trace/trace_preemptirq.c:45
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline]
 _raw_spin_lock_irqsave+0x6f/0xcd kernel/locking/spinlock.c:159
 __wake_up_common_lock+0xc8/0x150 kernel/sched/wait.c:122
 __wake_up+0xe/0x10 kernel/sched/wait.c:142
 netlink_unlock_table net/netlink/af_netlink.c:466 [inline]
 netlink_unlock_table net/netlink/af_netlink.c:463 [inline]
 netlink_broadcast_filtered+0x705/0xb80 net/netlink/af_netlink.c:1514
 netlink_broadcast+0x3a/0x50 net/netlink/af_netlink.c:1534
 rtnetlink_send+0xdd/0x110 net/core/rtnetlink.c:714
 tcf_add_notify net/sched/act_api.c:1343 [inline]
 tcf_action_add+0x243/0x370 net/sched/act_api.c:1362
 tc_ctl_action+0x3b5/0x4bc net/sched/act_api.c:1410
 rtnetlink_rcv_msg+0x463/0xb00 net/core/rtnetlink.c:5386
 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5404
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:657
 ___sys_sendmsg+0x803/0x920 net/socket.c:2311
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2356
 __do_sys_sendmsg net/socket.c:2365 [inline]
 __se_sys_sendmsg net/socket.c:2363 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2363
 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440939

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot+cf0adbb9c28c8866c788@syzkaller.appspotmail.com
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-15 20:20:22 -07:00
..
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 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-09-15 14:17:27 +02:00
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 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 53 2019-05-24 17:36:42 +02:00
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: sja1105: Fix sleeping while atomic in .port_hwtstamp_set 2019-10-02 12:19:53 -04:00
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 tcp: fix a possible lockdep splat in tcp_done() 2019-10-15 20:13:33 -07:00
ipv6 blackhole_netdev: fix syzkaller reported issue 2019-10-15 10:35:23 -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 netfilter: conntrack: avoid possible false sharing 2019-10-09 21:22:06 -07:00
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/sched: fix corrupted L2 header with MPLS 'push' and 'pop' actions 2019-10-15 17:14:48 -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: Fix possible NULL pointer access in ICMP handling 2019-10-11 21:20:23 -07:00
sched net: avoid potential infinite loop in tc_ctl_action() 2019-10-15 20:20:22 -07:00
sctp net: silence KCSAN warnings about sk->sk_backlog.len reads 2019-10-09 21:43:00 -07:00
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 Highlights: 2019-09-27 17:00:27 -07:00
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: Fix a lockdep warning in __vsock_release() 2019-10-01 21:23:35 -04:00
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
compat.c uio: make import_iovec()/compat_import_iovec() return bytes on success 2019-05-31 15:30:03 -06:00
Kconfig devlink: Add packet trap infrastructure 2019-08-17 12:40:08 -07:00
Makefile
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 treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00