WARNING: ODEBUG bug in __tcf_idr_release

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 98db2bf2 Linux 4.14.171
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10467129e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=49cf7d1ab0dd7451
dashboard link: https://syzkaller.appspot.com/bug?extid=bd6a673f11eb06a6b86c
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+bd6a67...@syzkaller.appspotmail.com

ODEBUG: free active (active state 1) object type: rcu_head hint: (null)
------------[ cut here ]------------
WARNING: CPU: 0 PID: 11176 at lib/debugobjects.c:287 debug_print_object.cold+0xa7/0xdb lib/debugobjects.c:287
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 11176 Comm: syz-executor.5 Not tainted 4.14.171-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x13e/0x194 lib/dump_stack.c:58
panic+0x1f9/0x42d kernel/panic.c:183
__warn.cold+0x2f/0x30 kernel/panic.c:547
report_bug+0x20a/0x248 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:963
RIP: 0010:debug_print_object.cold+0xa7/0xdb lib/debugobjects.c:287
RSP: 0018:ffff8880575171e8 EFLAGS: 00010082
RAX: 0000000000000051 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 000000000002f121 RSI: ffffffff81491330 RDI: ffffed100aea2e33
RBP: ffffffff86ab5ee0 R08: 0000000000000051 R09: 0000000000000000
R10: fffffbfff14a8cdf R11: ffff88805cd54100 R12: 0000000000000000
R13: 0000000000000001 R14: ffffffff8a6c9288 R15: ffff8880a5521038
__debug_check_no_obj_freed lib/debugobjects.c:747 [inline]
debug_check_no_obj_freed+0x3cd/0x6e4 lib/debugobjects.c:776
kfree+0xbb/0x260 mm/slab.c:3814
tcf_idr_remove net/sched/act_api.c:82 [inline]
__tcf_idr_release net/sched/act_api.c:101 [inline]
__tcf_idr_release+0x202/0x260 net/sched/act_api.c:85
tcf_idr_release include/net/act_api.h:150 [inline]
tcf_sample_init+0x788/0x8c0 net/sched/act_sample.c:80
tcf_action_init_1+0x51a/0x9f0 net/sched/act_api.c:682
tcf_action_init+0x26d/0x400 net/sched/act_api.c:751
tcf_action_add net/sched/act_api.c:1079 [inline]
tc_ctl_action+0x2e3/0x513 net/sched/act_api.c:1131
rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4315
netlink_rcv_skb+0x127/0x370 net/netlink/af_netlink.c:2432
netlink_unicast_kernel net/netlink/af_netlink.c:1286 [inline]
netlink_unicast+0x437/0x620 net/netlink/af_netlink.c:1312
netlink_sendmsg+0x733/0xbe0 net/netlink/af_netlink.c:1877
sock_sendmsg_nosec net/socket.c:646 [inline]
sock_sendmsg+0xc5/0x100 net/socket.c:656
___sys_sendmsg+0x70a/0x840 net/socket.c:2062
__sys_sendmsg+0xa3/0x120 net/socket.c:2096
SYSC_sendmsg net/socket.c:2107 [inline]
SyS_sendmsg+0x27/0x40 net/socket.c:2103
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45c449
RSP: 002b:00007ff4a4161c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ff4a41626d4 RCX: 000000000045c449
RDX: 0000000000000000 RSI: 0000000020002980 RDI: 0000000000000004
RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000009fa R14: 00000000004cc70b R15: 000000000076bf2c

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---
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[syzbot]

syzbot has found a reproducer for the following crash on:

HEAD commit: 98db2bf2 Linux 4.14.171
git tree: linux-4.14.y

console output: https://syzkaller.appspot.com/x/log.txt?x=116025a1e00000

kernel config: https://syzkaller.appspot.com/x/.config?x=49cf7d1ab0dd7451
dashboard link: https://syzkaller.appspot.com/bug?extid=bd6a673f11eb06a6b86c
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=149687d9e00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12b8e4c3e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+bd6a67...@syzkaller.appspotmail.com

random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
audit: type=1400 audit(1582740302.612:36): avc: denied { map } for pid=7360 comm="syz-executor124" path="/root/syz-executor124392399" dev="sda1" ino=16483 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1

ODEBUG: free active (active state 1) object type: rcu_head hint: (null)
------------[ cut here ]------------

WARNING: CPU: 0 PID: 7360 at lib/debugobjects.c:287 debug_print_object.cold+0xa7/0xdb lib/debugobjects.c:287

Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 7360 Comm: syz-executor124 Not tainted 4.14.171-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x13e/0x194 lib/dump_stack.c:58
panic+0x1f9/0x42d kernel/panic.c:183
__warn.cold+0x2f/0x30 kernel/panic.c:547
report_bug+0x20a/0x248 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:963
RIP: 0010:debug_print_object.cold+0xa7/0xdb lib/debugobjects.c:287

RSP: 0018:ffff888088fef1e8 EFLAGS: 00010082

RAX: 0000000000000051 RBX: 0000000000000003 RCX: 0000000000000000

RDX: 0000000000000000 RSI: ffffffff86ac07e0 RDI: ffffed10111fde33

RBP: ffffffff86ab5ee0 R08: 0000000000000051 R09: 0000000000000000

R10: fffffbfff14a8cdf R11: ffff88809e90c240 R12: 0000000000000000
R13: 0000000000000001 R14: ffffffff8a736488 R15: ffff88808e3d5a10

RIP: 0033:0x440369
RSP: 002b:00007ffd16ac0808 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440369
RDX: 0000000000000000 RSI: 0000000020002980 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 000000000000000b R09: 00000000004002c8
R10: 0000000000000040 R11: 0000000000000246 R12: 0000000000401bf0
R13: 0000000000401c80 R14: 0000000000000000 R15: 0000000000000000

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