Eric W. Biederman b9f75f45a6 netns: Don't receive new packets in a dead network namespace. ... Alexey Dobriyan <adobriyan@gmail.com> writes: > Subject: ICMP sockets destruction vs ICMP packets oops > After icmp_sk_exit() nuked ICMP sockets, we get an interrupt. > icmp_reply() wants ICMP socket. > > Steps to reproduce: > > launch shell in new netns > move real NIC to netns > setup routing > ping -i 0 > exit from shell > > BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 > IP: [<ffffffff803fce17>] icmp_sk+0x17/0x30 > PGD 17f3cd067 PUD 17f3ce067 PMD 0 > Oops: 0000 [1] PREEMPT SMP DEBUG_PAGEALLOC > CPU 0 > Modules linked in: usblp usbcore > Pid: 0, comm: swapper Not tainted 2.6.26-rc6-netns-ct #4 > RIP: 0010:[<ffffffff803fce17>] [<ffffffff803fce17>] icmp_sk+0x17/0x30 > RSP: 0018:ffffffff8057fc30 EFLAGS: 00010286 > RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff81017c7db900 > RDX: 0000000000000034 RSI: ffff81017c7db900 RDI: ffff81017dc41800 > RBP: ffffffff8057fc40 R08: 0000000000000001 R09: 000000000000a815 > R10: 0000000000000000 R11: 0000000000000001 R12: ffffffff8057fd28 > R13: ffffffff8057fd00 R14: ffff81017c7db938 R15: ffff81017dc41800 > FS: 0000000000000000(0000) GS:ffffffff80525000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b > CR2: 0000000000000000 CR3: 000000017fcda000 CR4: 00000000000006e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > Process swapper (pid: 0, threadinfo ffffffff8053a000, task ffffffff804fa4a0) > Stack: 0000000000000000 ffff81017c7db900 ffffffff8057fcf0 ffffffff803fcfe4 > ffffffff804faa38 0000000000000246 0000000000005a40 0000000000000246 > 000000000001ffff ffff81017dd68dc0 0000000000005a40 0000000055342436 > Call Trace: > <IRQ> [<ffffffff803fcfe4>] icmp_reply+0x44/0x1e0 > [<ffffffff803d3a0a>] ? ip_route_input+0x23a/0x1360 > [<ffffffff803fd645>] icmp_echo+0x65/0x70 > [<ffffffff803fd300>] icmp_rcv+0x180/0x1b0 > [<ffffffff803d6d84>] ip_local_deliver+0xf4/0x1f0 > [<ffffffff803d71bb>] ip_rcv+0x33b/0x650 > [<ffffffff803bb16a>] netif_receive_skb+0x27a/0x340 > [<ffffffff803be57d>] process_backlog+0x9d/0x100 > [<ffffffff803bdd4d>] net_rx_action+0x18d/0x250 > [<ffffffff80237be5>] __do_softirq+0x75/0x100 > [<ffffffff8020c97c>] call_softirq+0x1c/0x30 > [<ffffffff8020f085>] do_softirq+0x65/0xa0 > [<ffffffff80237af7>] irq_exit+0x97/0xa0 > [<ffffffff8020f198>] do_IRQ+0xa8/0x130 > [<ffffffff80212ee0>] ? mwait_idle+0x0/0x60 > [<ffffffff8020bc46>] ret_from_intr+0x0/0xf > <EOI> [<ffffffff80212f2c>] ? mwait_idle+0x4c/0x60 > [<ffffffff80212f23>] ? mwait_idle+0x43/0x60 > [<ffffffff8020a217>] ? cpu_idle+0x57/0xa0 > [<ffffffff8040f380>] ? rest_init+0x70/0x80 > Code: 10 5b 41 5c 41 5d 41 5e c9 c3 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 53 > 48 83 ec 08 48 8b 9f 78 01 00 00 e8 2b c7 f1 ff 89 c0 <48> 8b 04 c3 48 83 c4 08 > 5b c9 c3 66 66 66 66 66 2e 0f 1f 84 00 > RIP [<ffffffff803fce17>] icmp_sk+0x17/0x30 > RSP <ffffffff8057fc30> > CR2: 0000000000000000 > ---[ end trace ea161157b76b33e8 ]--- > Kernel panic - not syncing: Aiee, killing interrupt handler! Receiving packets while we are cleaning up a network namespace is a racy proposition. It is possible when the packet arrives that we have removed some but not all of the state we need to fully process it. We have the choice of either playing wack-a-mole with the cleanup routines or simply dropping packets when we don't have a network namespace to handle them. Since the check looks inexpensive in netif_receive_skb let's just drop the incoming packets. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2008-06-20 22:16:51 -07:00
..
9p	9p: fix error path during early mount	2008-05-14 19:23:27 -05:00
802
8021q	vlan: Use bitmask of feature flags instead of seperate feature bits	2008-05-23 00:27:50 -07:00
appletalk
atm	atm: [br2864] fix routed vcmux support	2008-06-16 17:18:18 -07:00
ax25	ax25: Fix NULL pointer dereference and lockup.	2008-06-03 14:53:46 -07:00
bluetooth	bluetooth: rfcomm_dev_state_change deadlock fix	2008-06-03 14:27:17 -07:00
bridge	bridge: Consolidate error paths in br_add_bridge().	2008-05-04 17:58:07 -07:00
can	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6	2008-05-08 19:03:26 -07:00
core	netns: Don't receive new packets in a dead network namespace.	2008-06-20 22:16:51 -07:00
dccp	dccp: Bug in initial acknowledgment number assignment	2008-06-11 11:19:10 +01:00
decnet	ip: Use inline function dst_metric() instead of direct access to dst->metric[]	2008-05-04 22:14:42 -07:00
econet	net: Allow netdevices to specify needed head/tailroom	2008-05-12 20:48:31 -07:00
ethernet
ieee80211
ipv4	xfrm: fix fragmentation for ipv4 xfrm tunnel	2008-06-17 16:38:23 -07:00
ipv6	ipv6: Drop packets for loopback address from outside of the box.	2008-06-19 16:33:57 -07:00
ipx
irda	irda: Sock leak on error path in irda_create.	2008-06-03 15:18:36 -07:00
iucv
key	ipsec: pfkey should ignore events when no listeners	2008-06-10 14:25:34 -07:00
lapb
llc	llc: Fix double accounting of received packets	2008-05-30 02:57:29 -07:00
mac80211	mac80211: detect driver tx bugs	2008-06-18 15:39:48 -07:00
netfilter	netfilter: nf_conntrack_h323: fix module unload crash	2008-06-17 15:52:32 -07:00
netlabel
netlink	netlink: genl: fix circular locking	2008-06-18 02:07:07 -07:00
netrom
packet	net: Allow netdevices to specify needed head/tailroom	2008-05-12 20:48:31 -07:00
rfkill
rose
rxrpc
sched	pkt_sched: Change HTB_HYSTERESIS to a runtime parameter htb_hysteresis.	2008-06-16 16:39:32 -07:00
sctp	sctp: Make sure N * sizeof(union sctp_addr) does not overflow.	2008-06-20 22:04:34 -07:00
sunrpc	Merge branch 'for-2.6.26' of git://linux-nfs.org/~bfields/linux	2008-05-20 19:30:54 -07:00
tipc	tipc: Increase buffer header to support worst-case device	2008-05-08 21:38:24 -07:00
unix	af_unix: fix 'poll for write'/ connected DGRAM sockets	2008-06-17 22:28:05 -07:00
wanrouter
wireless	netlink: Improve returned error codes	2008-06-03 16:36:54 -07:00
x25
xfrm	xfrm: xfrm_algo: correct usage of RIPEMD-160	2008-06-04 12:04:55 -07:00
compat.c
Kconfig
Makefile
nonet.c
socket.c
sysctl_net.c
TUNABLE