syzbot


WARNING: ODEBUG bug in qdisc_create
Status: fixed on 2022/03/08 16:11
Reported-by: syzbot+@syzkaller.appspotmail.com
Fix commit: a56d447f196f net/sched: sch_taprio: properly cancel timer from taprio_destroy()
First crash: 273d, last: 245d

Cause bisection: introduced by (bisect log) :
commit 44d4775ca51805b376a8db5b34f650434a08e556
Author: Davide Caratti <dcaratti@redhat.com>
Date: Wed Dec 16 18:33:29 2020 +0000

  net/sched: sch_taprio: reset child qdiscs before freeing them

Crash: WARNING: ODEBUG bug in qdisc_create (log)
Repro: C syz .config

Sample crash report:
netdevsim netdevsim0 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim0 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim0 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0
------------[ cut here ]------------
ODEBUG: free active (active state 0) object type: hrtimer hint: advance_sched+0x0/0x9a0 arch/x86/include/asm/atomic64_64.h:22
WARNING: CPU: 1 PID: 6522 at lib/debugobjects.c:505 debug_print_object+0x16e/0x250 lib/debugobjects.c:505
Modules linked in:
CPU: 0 PID: 6522 Comm: syz-executor645 Not tainted 5.15.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:debug_print_object+0x16e/0x250 lib/debugobjects.c:505
Code: ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 af 00 00 00 48 8b 14 dd 00 38 e4 89 4c 89 ee 48 c7 c7 00 2c e4 89 e8 da b2 14 05 <0f> 0b 83 05 55 0c 91 09 01 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e c3
RSP: 0018:ffffc90002def348 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: ffff888026023900 RSI: ffffffff815dbd98 RDI: fffff520005bde5b
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815d5b3e R11: 0000000000000000 R12: ffffffff898df0a0
R13: ffffffff89e43240 R14: ffffffff816581c0 R15: dffffc0000000000
FS:  0000555556878300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faee697d028 CR3: 0000000070fe7000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __debug_check_no_obj_freed lib/debugobjects.c:992 [inline]
 debug_check_no_obj_freed+0x301/0x420 lib/debugobjects.c:1023
 slab_free_hook mm/slub.c:1675 [inline]
 slab_free_freelist_hook+0xde/0x190 mm/slub.c:1725
 slab_free mm/slub.c:3483 [inline]
 kfree+0xe4/0x530 mm/slub.c:4543
 qdisc_create+0xbcf/0x1320 net/sched/sch_api.c:1299
 tc_modify_qdisc+0x4c8/0x1a60 net/sched/sch_api.c:1663
 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5572
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f9bdf070b89
Code: 28 c3 e8 4a 15 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc7b9d88c8 EFLAGS: 00000246
 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ffc7b9d88d8 RCX: 00007f9bdf070b89
RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000004
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc7b9d88e0
R13: 00007ffc7b9d8900 R14: 0000000000000000 R15: 0000000000000000

Crashes (6):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce 2021/09/21 05:30 upstream e8f71f89236e af796c18 .config log report syz C WARNING: ODEBUG bug in qdisc_create
ci-upstream-net-this-kasan-gce 2021/08/24 20:20 net 3b0720ba00a7 b599f2fc .config log report syz C WARNING: ODEBUG bug in qdisc_create
ci-upstream-net-kasan-gce 2021/08/24 19:52 net-next faf482ca196a b599f2fc .config log report syz C WARNING: ODEBUG bug in qdisc_create
ci-upstream-net-kasan-gce 2021/09/16 11:21 net-next 5706383b30cf 07e953c1 .config log report info WARNING: ODEBUG bug in qdisc_create
ci-upstream-net-kasan-gce 2021/08/24 19:29 net-next faf482ca196a b599f2fc .config log report info WARNING: ODEBUG bug in qdisc_create
ci-upstream-net-kasan-gce 2021/08/24 08:38 net-next f6a4e0e8a00f b599f2fc .config log report info WARNING: ODEBUG bug in qdisc_create