[syzbot] WARNING in netlink_sock_destruct

From: syzbot
Date: Wed Aug 04 2021 - 20:31:28 EST


Hello,

syzbot found the following issue on:

HEAD commit: f3438b4c4e69 Merge tag '5.14-rc3-smb3-fixes' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=127416d4300000
kernel config: https://syzkaller.appspot.com/x/.config?x=bfd78f4abd4edaa6
dashboard link: https://syzkaller.appspot.com/bug?extid=987e85fbd9c71706c130
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1
userspace arch: i386

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+987e85fbd9c71706c130@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
WARNING: CPU: 0 PID: 1042 at net/netlink/af_netlink.c:410 netlink_sock_destruct+0x230/0x2b0 net/netlink/af_netlink.c:410
Modules linked in:
CPU: 0 PID: 1042 Comm: syz-executor.0 Not tainted 5.14.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:netlink_sock_destruct+0x230/0x2b0 net/netlink/af_netlink.c:410
Code: df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 8a 00 00 00 48 83 bd d8 04 00 00 00 75 15 5b 5d 41 5c e9 a5 3a 22 fa e8 a0 3a 22 fa <0f> 0b e9 68 ff ff ff e8 94 3a 22 fa 0f 0b 5b 5d 41 5c e9 89 3a 22
RSP: 0018:ffffc90000007d90 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000407 RCX: 0000000000000100
RDX: ffff88808faa8000 RSI: ffffffff875360c0 RDI: 0000000000000003
RBP: ffff888000170000 R08: 0000000000000000 R09: ffff88800017020b
R10: ffffffff87536027 R11: 0000000000000000 R12: ffff888000170208
R13: ffff888000170030 R14: 0000000000000002 R15: ffff888000170688
FS: 0000000000000000(0000) GS:ffff8880b9c00000(0063) knlGS:00000000f552db40
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000002e826000 CR3: 00000000938ef000 CR4: 00000000001526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
__sk_destruct+0x4b/0x900 net/core/sock.c:1900
sk_destruct+0xbd/0xe0 net/core/sock.c:1944
__sk_free+0xef/0x3d0 net/core/sock.c:1955
sk_free+0x78/0xa0 net/core/sock.c:1966
deferred_put_nlk_sk+0x151/0x2f0 net/netlink/af_netlink.c:740
rcu_do_batch kernel/rcu/tree.c:2550 [inline]
rcu_core+0x7ab/0x1380 kernel/rcu/tree.c:2785
__do_softirq+0x29b/0x9c2 kernel/softirq.c:558
do_softirq.part.0+0xde/0x130 kernel/softirq.c:459
</IRQ>
do_softirq kernel/softirq.c:451 [inline]
__local_bh_enable_ip+0x102/0x120 kernel/softirq.c:383
local_bh_enable include/linux/bottom_half.h:32 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:757 [inline]
__dev_queue_xmit+0x1b04/0x3620 net/core/dev.c:4312
__netlink_deliver_tap_skb net/netlink/af_netlink.c:303 [inline]
__netlink_deliver_tap net/netlink/af_netlink.c:321 [inline]
netlink_deliver_tap+0x9b5/0xbc0 net/netlink/af_netlink.c:334
netlink_deliver_tap_kernel net/netlink/af_netlink.c:343 [inline]
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x5e5/0x7d0 net/netlink/af_netlink.c:1340
netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929
sock_sendmsg_nosec net/socket.c:703 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:723
sock_no_sendpage+0xf3/0x130 net/core/sock.c:2959
kernel_sendpage.part.0+0x1a0/0x340 net/socket.c:3673
kernel_sendpage net/socket.c:3670 [inline]
sock_sendpage+0xe5/0x140 net/socket.c:1002
pipe_to_sendpage+0x2ad/0x380 fs/splice.c:364
splice_from_pipe_feed fs/splice.c:418 [inline]
__splice_from_pipe+0x43e/0x8a0 fs/splice.c:562
splice_from_pipe fs/splice.c:597 [inline]
generic_splice_sendpage+0xd4/0x140 fs/splice.c:746
do_splice_from fs/splice.c:767 [inline]
do_splice+0xb7e/0x1960 fs/splice.c:1079
__do_splice+0x134/0x250 fs/splice.c:1144
__do_sys_splice fs/splice.c:1350 [inline]
__se_sys_splice fs/splice.c:1332 [inline]
__ia32_sys_splice+0x195/0x250 fs/splice.c:1332
do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
__do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203
entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f54549
Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f552d5fc EFLAGS: 00000296 ORIG_RAX: 0000000000000139
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000005 RSI: 0000000000000000 RDI: 000000000004ffe0
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000


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