Re: net/netlink: null-ptr-deref in netlink_dump/lock_acquire
From: Andrey Konovalov <hidden>
Date: 2016-11-03 17:21:30
Also in:
lkml
Hi,
Another report that looks related:
[ INFO: possible circular locking dependency detected ]
4.9.0-rc3+ #344 Not tainted
-------------------------------------------------------
syz-executor/25526 is trying to acquire lock:
([ 950.351060] &table[i].mutex
[<ffffffff82dcf798>] nfnl_lock+0x28/0x30 net/netfilter/nfnetlink.c:61
but task is already holding lock:
([ 950.351060] rtnl_mutex
[< inline >] rtnl_lock net/core/rtnetlink.c:70
[<ffffffff82c15efb>] rtnetlink_rcv+0x1b/0x40 net/core/rtnetlink.c:4032
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
:
[ 950.351060] [<ffffffff8120c52e>] lock_acquire+0x17e/0x340
kernel/locking/lockdep.c:3746
[ 950.351060] [< inline >] __mutex_lock_common
kernel/locking/mutex.c:521
[ 950.351060] [<ffffffff83fb7221>]
mutex_lock_nested+0xb1/0x890 kernel/locking/mutex.c:621
[ 950.351060] [<ffffffff82c11297>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:70
[ 950.351060] [<ffffffff839fe31f>]
nl80211_get_reg_dump+0x5f/0x400 net/wireless/nl80211.c:6171
[ 950.351060] [<ffffffff82dc18d8>] genl_lock_dumpit+0x68/0x90
net/netlink/genetlink.c:517
[ 950.351060] [<ffffffff82db6947>] netlink_dump+0x397/0xac0
net/netlink/af_netlink.c:2110
[ 950.351060] [<ffffffff82db99b1>]
__netlink_dump_start+0x501/0x770 net/netlink/af_netlink.c:2200
[ 950.351060] [<ffffffff82dc2cb8>]
genl_family_rcv_msg+0xad8/0xc80 net/netlink/genetlink.c:584
[ 950.351060] [<ffffffff82dc3016>] genl_rcv_msg+0x1b6/0x270
net/netlink/genetlink.c:658
[ 950.351060] [<ffffffff82dc10a0>] netlink_rcv_skb+0x2c0/0x3b0
net/netlink/af_netlink.c:2281
[ 950.351060] [<ffffffff82dc21c8>] genl_rcv+0x28/0x40
net/netlink/genetlink.c:669
[ 950.351060] [< inline >] netlink_unicast_kernel
net/netlink/af_netlink.c:1214
[ 950.351060] [<ffffffff82dbf959>] netlink_unicast+0x5a9/0x880
net/netlink/af_netlink.c:1240
[ 950.351060] [<ffffffff82dc05e7>] netlink_sendmsg+0x9b7/0xce0
net/netlink/af_netlink.c:1786
[ 950.351060] [< inline >] sock_sendmsg_nosec net/socket.c:606
[ 950.351060] [<ffffffff82b6f75c>] sock_sendmsg+0xcc/0x110
net/socket.c:616
[ 950.351060] [<ffffffff82b6f9c1>] sock_write_iter+0x221/0x3b0
net/socket.c:814
[ 950.351060] [< inline >] new_sync_write fs/read_write.c:499
[ 950.351060] [<ffffffff8151bd44>] __vfs_write+0x334/0x570
fs/read_write.c:512
[ 950.351060] [<ffffffff8151f85b>] vfs_write+0x17b/0x500
fs/read_write.c:560
[ 950.351060] [< inline >] SYSC_write fs/read_write.c:607
[ 950.351060] [<ffffffff81523184>] SyS_write+0xd4/0x1a0
fs/read_write.c:599
[ 950.351060] [<ffffffff83fc0281>] entry_SYSCALL_64_fastpath+0x1f/0xc2
:
[ 950.351060] [<ffffffff8120c52e>] lock_acquire+0x17e/0x340
kernel/locking/lockdep.c:3746
[ 950.351060] [< inline >] __mutex_lock_common
kernel/locking/mutex.c:521
[ 950.351060] [<ffffffff83fb7221>]
mutex_lock_nested+0xb1/0x890 kernel/locking/mutex.c:621
[ 950.351060] [< inline >] genl_lock net/netlink/genetlink.c:31
[ 950.351060] [<ffffffff82dc18b1>] genl_lock_dumpit+0x41/0x90
net/netlink/genetlink.c:516
[ 950.351060] [<ffffffff82db6947>] netlink_dump+0x397/0xac0
net/netlink/af_netlink.c:2110
[ 950.351060] [<ffffffff82db99b1>]
__netlink_dump_start+0x501/0x770 net/netlink/af_netlink.c:2200
[ 950.351060] [<ffffffff82dc2cb8>]
genl_family_rcv_msg+0xad8/0xc80 net/netlink/genetlink.c:584
[ 950.351060] [<ffffffff82dc3016>] genl_rcv_msg+0x1b6/0x270
net/netlink/genetlink.c:658
[ 950.351060] [<ffffffff82dc10a0>] netlink_rcv_skb+0x2c0/0x3b0
net/netlink/af_netlink.c:2281
[ 950.351060] [<ffffffff82dc21c8>] genl_rcv+0x28/0x40
net/netlink/genetlink.c:669
[ 950.351060] [< inline >] netlink_unicast_kernel
net/netlink/af_netlink.c:1214
[ 950.351060] [<ffffffff82dbf959>] netlink_unicast+0x5a9/0x880
net/netlink/af_netlink.c:1240
[ 950.351060] [<ffffffff82dc05e7>] netlink_sendmsg+0x9b7/0xce0
net/netlink/af_netlink.c:1786
[ 950.351060] [< inline >] sock_sendmsg_nosec net/socket.c:606
[ 950.351060] [<ffffffff82b6f75c>] sock_sendmsg+0xcc/0x110
net/socket.c:616
[ 950.351060] [<ffffffff82b6f9c1>] sock_write_iter+0x221/0x3b0
net/socket.c:814
[ 950.351060] [< inline >] new_sync_write fs/read_write.c:499
[ 950.351060] [<ffffffff8151bd44>] __vfs_write+0x334/0x570
fs/read_write.c:512
[ 950.351060] [<ffffffff8151f85b>] vfs_write+0x17b/0x500
fs/read_write.c:560
[ 950.351060] [< inline >] SYSC_write fs/read_write.c:607
[ 950.351060] [<ffffffff81523184>] SyS_write+0xd4/0x1a0
fs/read_write.c:599
[ 950.351060] [<ffffffff83fc0281>] entry_SYSCALL_64_fastpath+0x1f/0xc2
:
[ 950.351060] [<ffffffff8120c52e>] lock_acquire+0x17e/0x340
kernel/locking/lockdep.c:3746
[ 950.351060] [< inline >] __mutex_lock_common
kernel/locking/mutex.c:521
[ 950.351060] [<ffffffff83fb7221>]
mutex_lock_nested+0xb1/0x890 kernel/locking/mutex.c:621
[ 950.351060] [<ffffffff82db95aa>]
__netlink_dump_start+0xfa/0x770 net/netlink/af_netlink.c:2170
[ 950.351060] [< inline >] netlink_dump_start
include/linux/netlink.h:165
[ 950.351060] [<ffffffff82e19309>]
ctnetlink_stat_ct_cpu+0xd9/0x130
net/netfilter/nf_conntrack_netlink.c:2045
[ 950.351060] [<ffffffff82dd1d80>]
nfnetlink_rcv_msg+0xa10/0xc10 net/netfilter/nfnetlink.c:212
[ 950.351060] [<ffffffff82dc10a0>] netlink_rcv_skb+0x2c0/0x3b0
net/netlink/af_netlink.c:2281
[ 950.351060] [<ffffffff82dd07e8>] nfnetlink_rcv+0x848/0x1170
net/netfilter/nfnetlink.c:474
[ 950.351060] [< inline >] netlink_unicast_kernel
net/netlink/af_netlink.c:1214
[ 950.351060] [<ffffffff82dbf959>] netlink_unicast+0x5a9/0x880
net/netlink/af_netlink.c:1240
[ 950.351060] [<ffffffff82dc05e7>] netlink_sendmsg+0x9b7/0xce0
net/netlink/af_netlink.c:1786
[ 950.351060] [< inline >] sock_sendmsg_nosec net/socket.c:606
[ 950.351060] [<ffffffff82b6f75c>] sock_sendmsg+0xcc/0x110
net/socket.c:616
[ 950.351060] [<ffffffff82b6f9c1>] sock_write_iter+0x221/0x3b0
net/socket.c:814
[ 950.351060] [< inline >] new_sync_write fs/read_write.c:499
[ 950.351060] [<ffffffff8151bd44>] __vfs_write+0x334/0x570
fs/read_write.c:512
[ 950.351060] [<ffffffff8151f85b>] vfs_write+0x17b/0x500
fs/read_write.c:560
[ 950.351060] [< inline >] SYSC_write fs/read_write.c:607
[ 950.351060] [<ffffffff81523184>] SyS_write+0xd4/0x1a0
fs/read_write.c:599
[ 950.351060] [<ffffffff83fc0281>] entry_SYSCALL_64_fastpath+0x1f/0xc2
:
[ 950.351060] [< inline >] check_prev_add
kernel/locking/lockdep.c:1829
[ 950.351060] [< inline >] check_prevs_add
kernel/locking/lockdep.c:1939
[ 950.351060] [< inline >] validate_chain
kernel/locking/lockdep.c:2266
[ 950.351060] [<ffffffff8120b0ca>]
__lock_acquire+0x2b4a/0x3450 kernel/locking/lockdep.c:3335
[ 950.351060] [<ffffffff8120c52e>] lock_acquire+0x17e/0x340
kernel/locking/lockdep.c:3746
[ 950.351060] [< inline >] __mutex_lock_common
kernel/locking/mutex.c:521
[ 950.351060] [<ffffffff83fb7221>]
mutex_lock_nested+0xb1/0x890 kernel/locking/mutex.c:621
[ 950.351060] [<ffffffff82dcf798>] nfnl_lock+0x28/0x30
net/netfilter/nfnetlink.c:61
[ 950.351060] [<ffffffff82e847bf>]
nf_tables_netdev_event+0x14f/0x590
net/netfilter/nf_tables_netdev.c:122
[ 950.351060] [<ffffffff8117c131>]
notifier_call_chain+0x91/0x1a0 kernel/notifier.c:93
[ 950.351060] [< inline >] __raw_notifier_call_chain
kernel/notifier.c:394
[ 950.351060] [<ffffffff8117c2bd>]
raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
[ 950.351060] [<ffffffff82bc3851>]
call_netdevice_notifiers_info+0x51/0x90 net/core/dev.c:1645
[ 950.351060] [< inline >] call_netdevice_notifiers
net/core/dev.c:1661
[ 950.351060] [<ffffffff82be77c7>] dev_change_name+0x5d7/0x920
net/core/dev.c:1204
[ 950.351060] [<ffffffff82c171dd>] do_setlink+0x83d/0x30d0
net/core/rtnetlink.c:1993
[ 950.351060] [<ffffffff82c19ce0>] rtnl_setlink+0x270/0x330
net/core/rtnetlink.c:2231
[ 950.351060] [<ffffffff82c254a4>]
rtnetlink_rcv_msg+0x274/0x700 net/core/rtnetlink.c:4027
[ 950.351060] [<ffffffff82dc10a0>] netlink_rcv_skb+0x2c0/0x3b0
net/netlink/af_netlink.c:2281
[ 950.351060] [<ffffffff82c15f0a>] rtnetlink_rcv+0x2a/0x40
net/core/rtnetlink.c:4033
[ 950.351060] [< inline >] netlink_unicast_kernel
net/netlink/af_netlink.c:1214
[ 950.351060] [<ffffffff82dbf959>] netlink_unicast+0x5a9/0x880
net/netlink/af_netlink.c:1240
[ 950.351060] [<ffffffff82dc05e7>] netlink_sendmsg+0x9b7/0xce0
net/netlink/af_netlink.c:1786
[ 950.351060] [< inline >] sock_sendmsg_nosec net/socket.c:606
[ 950.351060] [<ffffffff82b6f75c>] sock_sendmsg+0xcc/0x110
net/socket.c:616
[ 950.351060] [<ffffffff82b6f9c1>] sock_write_iter+0x221/0x3b0
net/socket.c:814
[ 950.351060] [< inline >] new_sync_write fs/read_write.c:499
[ 950.351060] [<ffffffff8151bd44>] __vfs_write+0x334/0x570
fs/read_write.c:512
[ 950.351060] [<ffffffff8151f85b>] vfs_write+0x17b/0x500
fs/read_write.c:560
[ 950.351060] [< inline >] SYSC_write fs/read_write.c:607
[ 950.351060] [<ffffffff81523184>] SyS_write+0xd4/0x1a0
fs/read_write.c:599
[ 950.351060] [<ffffffff81006465>] do_syscall_64+0x195/0x490
arch/x86/entry/common.c:280
[ 950.351060] [<ffffffff83fc0349>] return_from_SYSCALL_64+0x0/0x7a
other info that might help us debug this:
Chain exists of:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock([ 950.351060] rtnl_mutex
);
lock([ 950.351060] genl_mutex
);
lock([ 950.351060] rtnl_mutex
);
lock([ 950.351060] &table[i].mutex
);
*** DEADLOCK ***
1 lock held by syz-executor/25526:
#0: [ 950.351060] (
stack backtrace:
CPU: 0 PID: 25526 Comm: syz-executor Not tainted 4.9.0-rc3+ #344
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
ffff8800692b6d30 ffffffff81b46934 ffffffff859bdf80 ffffffff859de740
ffffffff859b3870 1ffffffff0bade82 ffff8800692b6d80 ffffffff81204cfd
ffffffff859b3870 ffff88006859cca0 000000006859c480 ffff88006859cca0
Call Trace:
[< inline >] __dump_stack lib/dump_stack.c:15
[<ffffffff81b46934>] dump_stack+0xb3/0x10f lib/dump_stack.c:51
[<ffffffff81204cfd>] print_circular_bug+0x28d/0x350
kernel/locking/lockdep.c:1202
[< inline >] check_prev_add kernel/locking/lockdep.c:1829
[< inline >] check_prevs_add kernel/locking/lockdep.c:1939
[< inline >] validate_chain kernel/locking/lockdep.c:2266
[<ffffffff8120b0ca>] __lock_acquire+0x2b4a/0x3450 kernel/locking/lockdep.c:3335
[<ffffffff8120c52e>] lock_acquire+0x17e/0x340 kernel/locking/lockdep.c:3746
[< inline >] __mutex_lock_common kernel/locking/mutex.c:521
[<ffffffff83fb7221>] mutex_lock_nested+0xb1/0x890 kernel/locking/mutex.c:621
[<ffffffff82dcf798>] nfnl_lock+0x28/0x30 net/netfilter/nfnetlink.c:61
[<ffffffff82e847bf>] nf_tables_netdev_event+0x14f/0x590
net/netfilter/nf_tables_netdev.c:122
[<ffffffff8117c131>] notifier_call_chain+0x91/0x1a0 kernel/notifier.c:93
[< inline >] __raw_notifier_call_chain kernel/notifier.c:394
[<ffffffff8117c2bd>] raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
[<ffffffff82bc3851>] call_netdevice_notifiers_info+0x51/0x90
net/core/dev.c:1645
[< inline >] call_netdevice_notifiers net/core/dev.c:1661
[<ffffffff82be77c7>] dev_change_name+0x5d7/0x920 net/core/dev.c:1204
[<ffffffff82c171dd>] do_setlink+0x83d/0x30d0 net/core/rtnetlink.c:1993
[<ffffffff82c19ce0>] rtnl_setlink+0x270/0x330 net/core/rtnetlink.c:2231
[<ffffffff82c254a4>] rtnetlink_rcv_msg+0x274/0x700 net/core/rtnetlink.c:4027
[<ffffffff82dc10a0>] netlink_rcv_skb+0x2c0/0x3b0 net/netlink/af_netlink.c:2281
[<ffffffff82c15f0a>] rtnetlink_rcv+0x2a/0x40 net/core/rtnetlink.c:4033
[< inline >] netlink_unicast_kernel net/netlink/af_netlink.c:1214
[<ffffffff82dbf959>] netlink_unicast+0x5a9/0x880 net/netlink/af_netlink.c:1240
[<ffffffff82dc05e7>] netlink_sendmsg+0x9b7/0xce0 net/netlink/af_netlink.c:1786
[< inline >] sock_sendmsg_nosec net/socket.c:606
[<ffffffff82b6f75c>] sock_sendmsg+0xcc/0x110 net/socket.c:616
[<ffffffff82b6f9c1>] sock_write_iter+0x221/0x3b0 net/socket.c:814
[< inline >] new_sync_write fs/read_write.c:499
[<ffffffff8151bd44>] __vfs_write+0x334/0x570 fs/read_write.c:512
[<ffffffff8151f85b>] vfs_write+0x17b/0x500 fs/read_write.c:560
[< inline >] SYSC_write fs/read_write.c:607
[<ffffffff81523184>] SyS_write+0xd4/0x1a0 fs/read_write.c:599
[<ffffffff81006465>] do_syscall_64+0x195/0x490 arch/x86/entry/common.c:280
[<ffffffff83fc0349>] entry_SYSCALL64_slow_path+0x25/0x25
On Thu, Nov 3, 2016 at 4:08 AM, Andrey Konovalov [off-list ref] wrote:Hi Eric, This fixes the second report, the first one is still there. Apparently these are two separate issues. For the second one: Tested-by: Andrey Konovalov <redacted> Thanks for the fix! On Thu, Nov 3, 2016 at 3:58 AM, Eric Dumazet [off-list ref] wrote:quoted
On Thu, 2016-11-03 at 03:36 +0100, Andrey Konovalov wrote:quoted
On Thu, Nov 3, 2016 at 1:15 AM, Andrey Konovalov [off-list ref] wrote:quoted
On Wed, Oct 19, 2016 at 4:13 PM, Andrey Konovalov [off-list ref] wrote:quoted
Hi, I've got the following error report while running the syzkaller fuzzer: kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN Modules linked in: CPU: 1 PID: 3933 Comm: syz-executor Not tainted 4.9.0-rc1+ #230 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff88006b79d800 task.stack: ffff88006bbc0000 RIP: 0010:[<ffffffff8120872d>] [<ffffffff8120872d>] __lock_acquire+0x12d/0x3450 kernel/locking/lockdep.c:3221 RSP: 0018:ffff88006bbc7420 EFLAGS: 00010006 RAX: 0000000000000046 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 000000000000000c RSI: 0000000000000000 RDI: 0000000000000003 RBP: ffff88006bbc75c0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff85f42240 R12: ffff88006b79d800 R13: ffffffff84bfe4e0 R14: 0000000000000001 R15: 0000000000000060 FS: 00007fd9c41cc700(0000) GS:ffff88006cd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000451f80 CR3: 00000000638f0000 CR4: 00000000000006e0 Stack: 0000000000000000 ffff88006bbc0000 ffff88006bbc8000 0000000000000000 0000000000000002 ffff88006b79d800 0000000000000000 ffff88006bbc7f48 ffffffff852adc60 0000000000000000 ffffffff852adc64 1ffffffff0b40135 Call Trace: [<ffffffff8120c5ae>] lock_acquire+0x17e/0x340 kernel/locking/lockdep.c:3746 [< inline >] __mutex_lock_common kernel/locking/mutex.c:521 [<ffffffff83fb6fe1>] mutex_lock_nested+0xb1/0x890 kernel/locking/mutex.c:621 [<ffffffff82db6fd0>] netlink_dump+0x50/0xac0 net/netlink/af_netlink.c:2067 [<ffffffff82dba381>] __netlink_dump_start+0x501/0x770 net/netlink/af_netlink.c:2200 [<ffffffff82dc35b2>] genl_family_rcv_msg+0xa02/0xc80 net/netlink/genetlink.c:595 [<ffffffff82dc39e6>] genl_rcv_msg+0x1b6/0x270 net/netlink/genetlink.c:658 [<ffffffff82dc1a70>] netlink_rcv_skb+0x2c0/0x3b0 net/netlink/af_netlink.c:2281 [<ffffffff82dc2b98>] genl_rcv+0x28/0x40 net/netlink/genetlink.c:669 [< inline >] netlink_unicast_kernel net/netlink/af_netlink.c:1214 [<ffffffff82dc0329>] netlink_unicast+0x5a9/0x880 net/netlink/af_netlink.c:1240 [<ffffffff82dc0fb7>] netlink_sendmsg+0x9b7/0xce0 net/netlink/af_netlink.c:1786 [< inline >] sock_sendmsg_nosec net/socket.c:606 [<ffffffff82b7075c>] sock_sendmsg+0xcc/0x110 net/socket.c:616 [<ffffffff82b709c1>] sock_write_iter+0x221/0x3b0 net/socket.c:814 [< inline >] new_sync_write fs/read_write.c:499 [<ffffffff8151c944>] __vfs_write+0x334/0x570 fs/read_write.c:512 [<ffffffff8152045b>] vfs_write+0x17b/0x500 fs/read_write.c:560 [< inline >] SYSC_write fs/read_write.c:607 [<ffffffff81523d84>] SyS_write+0xd4/0x1a0 fs/read_write.c:599 [<ffffffff83fc0141>] entry_SYSCALL_64_fastpath+0x1f/0xc2 arch/x86/entry/entry_64.S:209 Code: 0f 1f 44 00 00 f6 c4 02 0f 85 24 0a 00 00 44 8b 35 c9 61 8b 03 45 85 f6 74 2c 4c 89 fa 48 bb 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 1a 00 0f 85 04 2f 00 00 49 81 3f a0 dc 2a 85 41 be 00 00 RIP [<ffffffff8120872d>] __lock_acquire+0x12d/0x3450 kernel/locking/lockdep.c:3221 RSP <ffff88006bbc7420> ---[ end trace 685b3c182bf7f25c ]--- The reproducer is attached. On commit 1a1891d762d6e64daf07b5be4817e3fbb29e3c59 (Oct 18).(Adding more maintainers) Still seeing this on 0c183d92b20b5c84ca655b45ef57b3318b83eb9e (Oct 31).Here is another report that might be related: ===================================== [ BUG: bad unlock balance detected! ] 4.9.0-rc3+ #336 Not tainted ------------------------------------- syz-executor/4018 is trying to release lock ([ 36.220068] nl_table_lock ) at: [<ffffffff82dc8683>] netlink_diag_dump+0x1a3/0x250 net/netlink/diag.c:182 but there are no more locks to release! other info that might help us debug this: 3 locks held by syz-executor/4018: #0: [ 36.220068] ( sock_diag_mutex[ 36.220068] ){+.+.+.} , at: [ 36.220068] [<ffffffff82c3873b>] sock_diag_rcv+0x1b/0x40 #1: [ 36.220068] ( sock_diag_table_mutex[ 36.220068] ){+.+.+.} , at: [ 36.220068] [<ffffffff82c38e00>] sock_diag_rcv_msg+0x140/0x3a0 #2: [ 36.220068] ( nlk->cb_mutex[ 36.220068] ){+.+.+.} , at: [ 36.220068] [<ffffffff82db6600>] netlink_dump+0x50/0xac0 stack backtrace: CPU: 1 PID: 4018 Comm: syz-executor Not tainted 4.9.0-rc3+ #336 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 ffff8800645df688 ffffffff81b46934 ffffffff84eb3e78 ffff88006ad85800 ffffffff82dc8683 ffffffff84eb3e78 ffff8800645df6b8 ffffffff812043ca dffffc0000000000 ffff88006ad85ff8 ffff88006ad85fd0 00000000ffffffff Call Trace: [< inline >] __dump_stack lib/dump_stack.c:15 [<ffffffff81b46934>] dump_stack+0xb3/0x10f lib/dump_stack.c:51 [<ffffffff812043ca>] print_unlock_imbalance_bug+0x17a/0x1a0 kernel/locking/lockdep.c:3388 [< inline >] __lock_release kernel/locking/lockdep.c:3512 [<ffffffff8120cfd8>] lock_release+0x8e8/0xc60 kernel/locking/lockdep.c:3765 [< inline >] __raw_read_unlock ./include/linux/rwlock_api_smp.h:225 [<ffffffff83fc001a>] _raw_read_unlock+0x1a/0x30 kernel/locking/spinlock.c:255 [<ffffffff82dc8683>] netlink_diag_dump+0x1a3/0x250 net/netlink/diag.c:182 [<ffffffff82db6947>] netlink_dump+0x397/0xac0 net/netlink/af_netlink.c:2110 [<ffffffff82db99b1>] __netlink_dump_start+0x501/0x770 net/netlink/af_netlink.c:2200 [< inline >] netlink_dump_start ./include/linux/netlink.h:165 [<ffffffff82dc75d1>] netlink_diag_handler_dump+0x191/0x220 net/netlink/diag.c:218 [< inline >] __sock_diag_cmd net/core/sock_diag.c:239 [<ffffffff82c38fd6>] sock_diag_rcv_msg+0x316/0x3a0 net/core/sock_diag.c:270 [<ffffffff82dc10a0>] netlink_rcv_skb+0x2c0/0x3b0 net/netlink/af_netlink.c:2281 [<ffffffff82c3874a>] sock_diag_rcv+0x2a/0x40 net/core/sock_diag.c:281 [< inline >] netlink_unicast_kernel net/netlink/af_netlink.c:1214 [<ffffffff82dbf959>] netlink_unicast+0x5a9/0x880 net/netlink/af_netlink.c:1240 [<ffffffff82dc05e7>] netlink_sendmsg+0x9b7/0xce0 net/netlink/af_netlink.c:1786 [< inline >] sock_sendmsg_nosec net/socket.c:606 [<ffffffff82b6f75c>] sock_sendmsg+0xcc/0x110 net/socket.c:616 [<ffffffff82b6f9c1>] sock_write_iter+0x221/0x3b0 net/socket.c:814 [< inline >] new_sync_write fs/read_write.c:499 [<ffffffff8151bd44>] __vfs_write+0x334/0x570 fs/read_write.c:512 [<ffffffff8151f85b>] vfs_write+0x17b/0x500 fs/read_write.c:560 [< inline >] SYSC_write fs/read_write.c:607 [<ffffffff81523184>] SyS_write+0xd4/0x1a0 fs/read_write.c:599 [<ffffffff83fc0401>] entry_SYSCALL_64_fastpath+0x1f/0xc2 arch/x86/entry/entry_64.S:209 ------------[ cut here ]------------ WARNING: CPU: 1 PID: 4018 at net/core/skbuff.c:654[< none >] skb_release_head_state+0x1ca/0x240 net/core/skbuff.c:654 Modules linked in: CPU: 1 PID: 4018 Comm: syz-executor Not tainted 4.9.0-rc3+ #336 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 ffff8800645df920 ffffffff81b46934 0000000000000000 0000000000000000 ffffffff84401fa0 0000000000000000 ffff8800645df968 ffffffff811112f7 ffffffff83fb92f2 ffff88000000028e ffffffff84401fa0 000000000000028e Call Trace: [< inline >] __dump_stack lib/dump_stack.c:15 [<ffffffff81b46934>] dump_stack+0xb3/0x10f lib/dump_stack.c:51 [<ffffffff811112f7>] __warn+0x1a7/0x1f0 kernel/panic.c:550 [<ffffffff8111150c>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585 [<ffffffff82b885ea>] skb_release_head_state+0x1ca/0x240 net/core/skbuff.c:654 [<ffffffff82b91815>] skb_release_all+0x15/0x60 net/core/skbuff.c:668 [< inline >] __kfree_skb net/core/skbuff.c:684 [<ffffffff82ba0175>] consume_skb+0x115/0x2e0 net/core/skbuff.c:757 [< inline >] netlink_unicast_kernel net/netlink/af_netlink.c:1215 [<ffffffff82dbf961>] netlink_unicast+0x5b1/0x880 net/netlink/af_netlink.c:1240 [<ffffffff82dc05e7>] netlink_sendmsg+0x9b7/0xce0 net/netlink/af_netlink.c:1786 [< inline >] sock_sendmsg_nosec net/socket.c:606 [<ffffffff82b6f75c>] sock_sendmsg+0xcc/0x110 net/socket.c:616 [<ffffffff82b6f9c1>] sock_write_iter+0x221/0x3b0 net/socket.c:814 [< inline >] new_sync_write fs/read_write.c:499 [<ffffffff8151bd44>] __vfs_write+0x334/0x570 fs/read_write.c:512 [<ffffffff8151f85b>] vfs_write+0x17b/0x500 fs/read_write.c:560 [< inline >] SYSC_write fs/read_write.c:607 [<ffffffff81523184>] SyS_write+0xd4/0x1a0 fs/read_write.c:599 [<ffffffff83fc0401>] entry_SYSCALL_64_fastpath+0x1f/0xc2 arch/x86/entry/entry_64.S:209 ---[ end trace bb9fa7cf182d59a5 ]--- BUG: scheduling while atomic: syz-executor/4018/0x7fffffff INFO: lockdep is turned off. Modules linked in: CPU: 1 PID: 4018 Comm: syz-executor Tainted: G W 4.9.0-rc3+ #336 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 ffff8800645dfe28 ffffffff81b46934 dffffc0000000000 000000007fffffff 00000000000214c0 0000000000000001 ffff8800645dfe48 ffffffff8119113a ffff88006cd214c0 0000000000000000 ffff8800645dfec8 ffffffff83fb030a Call Trace: [< inline >] __dump_stack lib/dump_stack.c:15 [<ffffffff81b46934>] dump_stack+0xb3/0x10f lib/dump_stack.c:51 [<ffffffff8119113a>] __schedule_bug+0xfa/0x140 kernel/sched/core.c:3230 [< inline >] schedule_debug kernel/sched/core.c:3245 [<ffffffff83fb030a>] __schedule+0xfda/0x1ab0 kernel/sched/core.c:3345 [<ffffffff83fb0e70>] schedule+0x90/0x1b0 kernel/sched/core.c:3457 [<ffffffff810039e9>] exit_to_usermode_loop+0xc9/0x130 arch/x86/entry/common.c:149 [< inline >] prepare_exit_to_usermode arch/x86/entry/common.c:190 [<ffffffff81006298>] syscall_return_slowpath+0x1a8/0x1e0 arch/x86/entry/common.c:259 [<ffffffff83fc04a2>] entry_SYSCALL_64_fastpath+0xc0/0xc2 arch/x86/entry/entry_64.S:244 NOHZ: local_softirq_pending 202 ------------[ cut here ]------------ WARNING: CPU: 1 PID: 4018 at net/core/skbuff.c:654[< none >] skb_release_head_state+0x1ca/0x240 net/core/skbuff.c:654 Modules linked in:[ 36.328353] CPU: 1 PID: 4018 Comm: syz-executor Tainted: G W 4.9.0-rc3+ #336 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 ffff8800645df920 ffffffff81b46934 0000000000000000 0000000000000000 ffffffff84401fa0 0000000000000000 ffff8800645df968 ffffffff811112f7 ffffffff83fb92f2 ffff88000000028e ffffffff84401fa0 000000000000028e Call Trace: [< inline >] __dump_stack lib/dump_stack.c:15 [<ffffffff81b46934>] dump_stack+0xb3/0x10f lib/dump_stack.c:51 [<ffffffff811112f7>] __warn+0x1a7/0x1f0 kernel/panic.c:550 [<ffffffff8111150c>] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585 [<ffffffff82b885ea>] skb_release_head_state+0x1ca/0x240 net/core/skbuff.c:654 [<ffffffff82b91815>] skb_release_all+0x15/0x60 net/core/skbuff.c:668 [< inline >] __kfree_skb net/core/skbuff.c:684 [<ffffffff82ba0175>] consume_skb+0x115/0x2e0 net/core/skbuff.c:757 [< inline >] netlink_unicast_kernel net/netlink/af_netlink.c:1215 [<ffffffff82dbf961>] netlink_unicast+0x5b1/0x880 net/netlink/af_netlink.c:1240 [<ffffffff82dc05e7>] netlink_sendmsg+0x9b7/0xce0 net/netlink/af_netlink.c:1786 [< inline >] sock_sendmsg_nosec net/socket.c:606 [<ffffffff82b6f75c>] sock_sendmsg+0xcc/0x110 net/socket.c:616 [<ffffffff82b6f9c1>] sock_write_iter+0x221/0x3b0 net/socket.c:814 [< inline >] new_sync_write fs/read_write.c:499 [<ffffffff8151bd44>] __vfs_write+0x334/0x570 fs/read_write.c:512 [<ffffffff8151f85b>] vfs_write+0x17b/0x500 fs/read_write.c:560 [< inline >] SYSC_write fs/read_write.c:607 [<ffffffff81523184>] SyS_write+0xd4/0x1a0 fs/read_write.c:599 [<ffffffff83fc0401>] entry_SYSCALL_64_fastpath+0x1f/0xc2 arch/x86/entry/entry_64.S:209 ---[ end trace bb9fa7cf182d59a6 ]--- BUG: sleeping function called from invalid context at ./include/linux/freezer.h:56 in_atomic(): 1, irqs_disabled(): 0, pid: 4018, name: syz-executor INFO: lockdep is turned off. CPU: 1 PID: 4018 Comm: syz-executor Tainted: G W 4.9.0-rc3+ #336 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 ffff8800645dfbb0 ffffffff81b46934 ffff88006ad85800 ffff8800645d8000 ffff88006ad85800 0000000000000000 ffff8800645dfbd8 ffffffff81192131 ffff88006ad85800 ffffffff8404c140 0000000000000038 ffff8800645dfc18 Call Trace: [< inline >] __dump_stack lib/dump_stack.c:15 [<ffffffff81b46934>] dump_stack+0xb3/0x10f lib/dump_stack.c:51 [<ffffffff81192131>] ___might_sleep+0x281/0x3c0 kernel/sched/core.c:7767 [<ffffffff81192306>] __might_sleep+0x96/0x1a0 kernel/sched/core.c:7726 [< inline >] try_to_freeze_unsafe ./include/linux/freezer.h:56 [< inline >] try_to_freeze ./include/linux/freezer.h:66 [<ffffffff81143849>] get_signal+0x129/0x15a0 kernel/signal.c:2147 [<ffffffff81054aad>] do_signal+0x8d/0x1a30 arch/x86/kernel/signal.c:807 [<ffffffff81003a05>] exit_to_usermode_loop+0xe5/0x130 arch/x86/entry/common.c:156 [< inline >] prepare_exit_to_usermode arch/x86/entry/common.c:190 [<ffffffff81006298>] syscall_return_slowpath+0x1a8/0x1e0 arch/x86/entry/common.c:259 [<ffffffff83fc04a2>] entry_SYSCALL_64_fastpath+0xc0/0xc2 arch/x86/entry/entry_64.S:244 Kernel panic - not syncing: Aiee, killing interrupt handler! CPU: 1 PID: 4018 Comm: syz-executor Tainted: G W 4.9.0-rc3+ #336 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 ffff8800645df998 ffffffff81b46934 0000000000000003 dffffc0000000000 dffffc0000000000 ffff8800645dfa04 ffff8800645dfa60 ffffffff8140bf7a 0000000041b58ab3 ffffffff84797a7d ffffffff8140bdbe ffffffff00000000 Call Trace: [< inline >] __dump_stack lib/dump_stack.c:15 [<ffffffff81b46934>] dump_stack+0xb3/0x10f lib/dump_stack.c:51 [<ffffffff8140bf7a>] panic+0x1bc/0x39d kernel/panic.c:179 [<ffffffff8111cfd8>] do_exit+0x1b48/0x2ac0 kernel/exit.c:740 [<ffffffff811222be>] do_group_exit+0x10e/0x340 kernel/exit.c:931 [<ffffffff81143d54>] get_signal+0x634/0x15a0 kernel/signal.c:2307 [<ffffffff81054aad>] do_signal+0x8d/0x1a30 arch/x86/kernel/signal.c:807 [<ffffffff81003a05>] exit_to_usermode_loop+0xe5/0x130 arch/x86/entry/common.c:156 [< inline >] prepare_exit_to_usermode arch/x86/entry/common.c:190 [<ffffffff81006298>] syscall_return_slowpath+0x1a8/0x1e0 arch/x86/entry/common.c:259 [<ffffffff83fc04a2>] entry_SYSCALL_64_fastpath+0xc0/0xc2 arch/x86/entry/entry_64.S:244 Kernel Offset: disabled ---[ end Kernel panic - not syncing: Aiee, killing interrupt handler!This is probably a leftover after commit ad202074320cd75b31b8cdb58cca0d4ef6aaea8a ("netlink: Use rhashtable walk interface in diag dump") Please try this trivial fix :diff --git a/net/netlink/diag.c b/net/netlink/diag.c index b2f0e986a6f4..a5546249fb10 100644 --- a/net/netlink/diag.c +++ b/net/netlink/diag.c@@ -178,11 +178,8 @@ static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) } cb->args[1] = i; } else { - if (req->sdiag_protocol >= MAX_LINKS) { - read_unlock(&nl_table_lock); - rcu_read_unlock(); + if (req->sdiag_protocol >= MAX_LINKS) return -ENOENT; - } err = __netlink_diag_dump(skb, cb, req->sdiag_protocol, s_num); }