Vitaly Mayatskikh 30842f2989 udp: Wrong locking code in udp seq_file infrastructure ... Reading zero bytes from /proc/net/udp or other similar files which use the same seq_file udp infrastructure panics kernel in that way: ===================================== [ BUG: bad unlock balance detected! ] ------------------------------------- read/1985 is trying to release lock (&table->hash[i].lock) at: [<ffffffff81321d83>] udp_seq_stop+0x27/0x29 but there are no more locks to release! other info that might help us debug this: 1 lock held by read/1985: #0: (&p->lock){--..}, at: [<ffffffff810eefb6>] seq_read+0x38/0x348 stack backtrace: Pid: 1985, comm: read Not tainted 2.6.29-rc8 #9 Call Trace: [<ffffffff81321d83>] ? udp_seq_stop+0x27/0x29 [<ffffffff8106dab9>] print_unlock_inbalance_bug+0xd6/0xe1 [<ffffffff8106db62>] lock_release_non_nested+0x9e/0x1c6 [<ffffffff810ef030>] ? seq_read+0xb2/0x348 [<ffffffff8106bdba>] ? mark_held_locks+0x68/0x86 [<ffffffff81321d83>] ? udp_seq_stop+0x27/0x29 [<ffffffff8106dde7>] lock_release+0x15d/0x189 [<ffffffff8137163c>] _spin_unlock_bh+0x1e/0x34 [<ffffffff81321d83>] udp_seq_stop+0x27/0x29 [<ffffffff810ef239>] seq_read+0x2bb/0x348 [<ffffffff810eef7e>] ? seq_read+0x0/0x348 [<ffffffff8111aedd>] proc_reg_read+0x90/0xaf [<ffffffff810d878f>] vfs_read+0xa6/0x103 [<ffffffff8106bfac>] ? trace_hardirqs_on_caller+0x12f/0x153 [<ffffffff810d88a2>] sys_read+0x45/0x69 [<ffffffff8101123a>] system_call_fastpath+0x16/0x1b BUG: scheduling while atomic: read/1985/0xffffff00 INFO: lockdep is turned off. Modules linked in: cpufreq_ondemand acpi_cpufreq freq_table dm_multipath kvm ppdev snd_hda_codec_analog snd_hda_intel snd_hda_codec snd_hwdep snd_seq_dummy snd_seq_oss snd_seq_midi_event arc4 snd_s eq ecb thinkpad_acpi snd_seq_device iwl3945 hwmon sdhci_pci snd_pcm_oss sdhci rfkill mmc_core snd_mixer_oss i2c_i801 mac80211 yenta_socket ricoh_mmc i2c_core iTCO_wdt snd_pcm iTCO_vendor_support rs rc_nonstatic snd_timer snd lib80211 cfg80211 soundcore snd_page_alloc video parport_pc output parport e1000e [last unloaded: scsi_wait_scan] Pid: 1985, comm: read Not tainted 2.6.29-rc8 #9 Call Trace: [<ffffffff8106b456>] ? __debug_show_held_locks+0x1b/0x24 [<ffffffff81043660>] __schedule_bug+0x7e/0x83 [<ffffffff8136ede9>] schedule+0xce/0x838 [<ffffffff810d7972>] ? fsnotify_access+0x5f/0x67 [<ffffffff810112d0>] ? sysret_careful+0xb/0x37 [<ffffffff8106be9c>] ? trace_hardirqs_on_caller+0x1f/0x153 [<ffffffff8137127b>] ? trace_hardirqs_on_thunk+0x3a/0x3f [<ffffffff810112f6>] sysret_careful+0x31/0x37 read[1985]: segfault at 7fffc479bfe8 ip 0000003e7420a180 sp 00007fffc479bfa0 error 6 Kernel panic - not syncing: Aiee, killing interrupt handler! udp_seq_stop() tries to unlock not yet locked spinlock. The lock was lost during splitting global udp_hash_lock to subsequent spinlocks. Signed-off by: Vitaly Mayatskikh <v.mayatskih@gmail.com> Acked-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2009-03-23 15:22:33 -07:00
..
netfilter	netfilter 06/09: nf_conntrack: fix ICMP/ICMPv6 timeout sysctls on big-endian	2009-01-12 21:18:35 -08:00
af_inet.c	netns: igmp: allow IPPROTO_IGMP sockets in netns	2008-12-25 16:42:23 -08:00
ah4.c	netns xfrm: AH/ESP in netns!	2008-11-25 17:59:27 -08:00
arp.c	ipv4: Fix ARP behavior with many mac-vlans	2008-11-16 19:19:38 -08:00
cipso_ipv4.c	cipso: Fix documentation comment	2009-02-23 10:05:54 +11:00
datagram.c
devinet.c
esp4.c	netns xfrm: AH/ESP in netns!	2008-11-25 17:59:27 -08:00
fib_frontend.c
fib_hash.c
fib_lookup.h
fib_rules.c
fib_semantics.c
fib_trie.c
icmp.c	netns: Fix icmp shutdown.	2009-03-03 01:14:15 -08:00
igmp.c	netns: igmp: make /proc/net/{igmp,mcfilter} per netns	2008-12-25 16:42:51 -08:00
inet_connection_sock.c	net: Fix percpu counters deadlock	2008-12-29 23:04:08 -08:00
inet_diag.c	net: Convert TCP/DCCP listening hash tables to use RCU	2008-11-23 17:22:55 -08:00
inet_fragment.c
inet_hashtables.c	net: Make sure BHs are disabled in sock_prot_inuse_add()	2008-11-24 00:09:29 -08:00
inet_lro.c	include/net net/ - csum_partial - remove unnecessary casts	2008-11-19 15:44:53 -08:00
inet_timewait_sock.c	net: convert TCP/DCCP ehash rwlocks to spinlocks	2008-11-20 20:39:09 -08:00
inetpeer.c
ip_forward.c
ip_fragment.c	netns: oops in ip[6]_frag_reasm incrementing stats	2009-03-18 23:26:11 -07:00
ip_gre.c	net: fix tunnels in netns after ndo_ changes	2008-11-23 17:26:26 -08:00
ip_input.c	Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6	2008-11-18 23:38:23 -08:00
ip_options.c
ip_output.c	net: avoid a pair of dst_hold()/dst_release() in ip_push_pending_frames()	2008-11-24 16:07:50 -08:00
ip_sockglue.c	net: ip_sockglue.c add static, annotate ports' endianness	2008-11-20 01:54:27 -08:00
ipcomp.c	netns xfrm: state lookup in netns	2008-11-25 17:30:50 -08:00
ipconfig.c	ipv4: fix infinite retry loop in IP-Config	2009-01-29 16:19:13 -08:00
ipip.c	net: fix tunnels in netns after ndo_ changes	2008-11-23 17:26:26 -08:00
ipmr.c	ipmr: merge common code	2008-12-16 01:15:11 -08:00
Kconfig
Makefile
netfilter.c	Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6	2008-11-28 02:19:15 -08:00
proc.c	net: Fix percpu counters deadlock	2008-12-29 23:04:08 -08:00
protocol.c
raw.c	net: avoid a pair of dst_hold()/dst_release() in ip_append_data()	2008-11-24 15:52:46 -08:00
route.c	cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits: net	2008-12-29 22:44:47 -08:00
syncookies.c
sysctl_net_ipv4.c
tcp_bic.c
tcp_cong.c
tcp_cubic.c
tcp_diag.c	net: inet_diag_handler structs can be const	2008-11-19 15:43:27 -08:00
tcp_highspeed.c
tcp_htcp.c	tcp_htcp: last_cong bug fix	2008-11-12 01:41:09 -08:00
tcp_hybla.c
tcp_illinois.c
tcp_input.c	tcp: fix retrans_out leaks	2009-03-01 00:21:36 -08:00
tcp_ipv4.c	tcp: Like icmp use register_pernet_subsys	2009-03-03 01:14:21 -08:00
tcp_lp.c
tcp_minisocks.c
tcp_output.c	tcp: remove obsoleted comment about different passes	2009-02-18 17:45:44 -08:00
tcp_probe.c
tcp_scalable.c	tcp_scalable: Update malformed & dead url	2009-02-24 16:40:16 -08:00
tcp_timer.c	tcp: Stop scaring users with "treason uncloaked!"	2008-12-18 22:27:42 -08:00
tcp_vegas.c	tcp: tcp_vegas cong avoid fix	2008-12-09 00:13:04 -08:00
tcp_vegas.h
tcp_veno.c
tcp_westwood.c
tcp_yeah.c
tcp.c	tcp: Fix length tcp_splice_data_recv passes to skb_splice_bits.	2009-01-26 22:15:31 -08:00
tunnel4.c
udp_impl.h
udp.c	udp: Wrong locking code in udp seq_file infrastructure	2009-03-23 15:22:33 -07:00
udplite.c
xfrm4_input.c	ipsec: Remove useless ret variable	2008-12-26 01:31:18 -08:00
xfrm4_mode_beet.c
xfrm4_mode_transport.c
xfrm4_mode_tunnel.c
xfrm4_output.c
xfrm4_policy.c	netns xfrm: ->get_saddr in netns	2008-11-25 17:56:49 -08:00
xfrm4_state.c	xfrm: remove useless forward declarations	2008-11-25 01:05:54 -08:00
xfrm4_tunnel.c