[syzbot] [net?] WARNING: ODEBUG bug in ingress_destroy

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 03b123debcbc tcp: tcp_enter_quickack_mode() should be static
git tree: net-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=168e1baaa80000
kernel config: https://syzkaller.appspot.com/x/.config?x=32e3dcc11fd0d297
dashboard link: https://syzkaller.appspot.com/bug?extid=bdcf141f362ef83335cf
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10bf2bf4a80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12741e9aa80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/348462fb61fa/disk-03b123de.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/33375730f77f/vmlinux-03b123de.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b6882fbac041/bzImage-03b123de.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+bdcf14...@syzkaller.appspotmail.com

------------[ cut here ]------------
ODEBUG: activate active (active state 1) object: ffff88807f28f000 object type: rcu_head hint: 0x0
WARNING: CPU: 0 PID: 5029 at lib/debugobjects.c:514 debug_print_object+0x19e/0x2a0 lib/debugobjects.c:514
Modules linked in:
CPU: 0 PID: 5029 Comm: syz-executor389 Not tainted 6.5.0-rc1-syzkaller-00458-g03b123debcbc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
RIP: 0010:debug_print_object+0x19e/0x2a0 lib/debugobjects.c:514
Code: 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 49 48 8b 14 dd c0 20 c8 8a 41 56 4c 89 e6 48 c7 c7 20 14 c8 8a e8 b2 fa 28 fd <0f> 0b 58 83 05 5c 8b 87 0a 01 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e
RSP: 0018:ffffc90003a5f168 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: ffff8880269b1dc0 RSI: ffffffff814d4986 RDI: 0000000000000001
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffffffff8ac81a80
R13: ffffffff8a6df720 R14: 0000000000000000 R15: ffff888017f63360
FS: 0000555555f7f380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000007b9d8000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
debug_object_activate+0x32b/0x490 lib/debugobjects.c:733
debug_rcu_head_queue kernel/rcu/rcu.h:226 [inline]
kvfree_call_rcu+0x30/0xbe0 kernel/rcu/tree.c:3359
tcx_entry_free include/net/tcx.h:96 [inline]
ingress_destroy+0x39f/0x520 net/sched/sch_ingress.c:127
__qdisc_destroy+0xc4/0x450 net/sched/sch_generic.c:1063
qdisc_destroy+0x4f/0x60 net/sched/sch_generic.c:1078
qdisc_graft+0x6f9/0x1680 net/sched/sch_api.c:1132
tc_modify_qdisc+0xcd2/0x1bf0 net/sched/sch_api.c:1731
rtnetlink_rcv_msg+0x439/0xd30 net/core/rtnetlink.c:6423
netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2546
netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
netlink_unicast+0x539/0x800 net/netlink/af_netlink.c:1365
netlink_sendmsg+0x93c/0xe30 net/netlink/af_netlink.c:1911
sock_sendmsg_nosec net/socket.c:725 [inline]
sock_sendmsg+0xd9/0x180 net/socket.c:748
____sys_sendmsg+0x6ac/0x940 net/socket.c:2494
___sys_sendmsg+0x135/0x1d0 net/socket.c:2548
__sys_sendmsg+0x117/0x1e0 net/socket.c:2577
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f1232c17839
Code: 48 83 c4 28 c3 e8 27 18 00 00 0f 1f 80 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc05125308 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000000003f RCX: 00007f1232c17839
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 00007f1232c8e0d0 R08: 00007ffc05125380 R09: 00007ffc05125380
R10: 00007ffc05125380 R11: 0000000000000246 R12: 00007f1232c8a5f0
R13: 00007ffc05125508 R14: 0000000000000001 R15: 0000000000000001
</TASK>


---
This report is generated by a bot. It may contain errors.
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[Daniel Borkmann]

On 7/20/23 5:18 PM, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 03b123debcbc tcp: tcp_enter_quickack_mode() should be static
> git tree: net-next
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=168e1baaa80000
> kernel config: https://syzkaller.appspot.com/x/.config?x=32e3dcc11fd0d297
> dashboard link: https://syzkaller.appspot.com/bug?extid=bdcf141f362ef83335cf
> compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10bf2bf4a80000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12741e9aa80000
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/348462fb61fa/disk-03b123de.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/33375730f77f/vmlinux-03b123de.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/b6882fbac041/bzImage-03b123de.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+bdcf14...@syzkaller.appspotmail.com

Same here, will take a look. Thanks!

[syzbot]

> On 7/20/23 5:18 PM, syzbot wrote:
>> Hello,
>>
>> syzbot found the following issue on:
>>
>> HEAD commit: 03b123debcbc tcp: tcp_enter_quickack_mode() should be static
>> git tree: net-next
>> console+strace: https://syzkaller.appspot.com/x/log.txt?x=168e1baaa80000
>> kernel config: https://syzkaller.appspot.com/x/.config?x=32e3dcc11fd0d297
>> dashboard link: https://syzkaller.appspot.com/bug?extid=bdcf141f362ef83335cf
>> compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
>> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10bf2bf4a80000
>> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12741e9aa80000
>
>

> #syz test: https://github.com/cilium/linux.git pr/new-api-tcx8

Your commands are accepted, but please keep syzkall...@googlegroups.com mailing list in CC next time. It serves as a history of what happened with each bug report. Thank you.

[Hillf Danton]

On Thu, 20 Jul 2023 08:18:15 -0700

> HEAD commit: 03b123debcbc tcp: tcp_enter_quickack_mode() should be static
> git tree: net-next

> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12741e9aa80000

Reset tcx_ingress after freeing it.

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git 03b123debcbc

--- x/net/sched/sch_ingress.c
+++ y/net/sched/sch_ingress.c
@@ -123,7 +123,7 @@ static void ingress_destroy(struct Qdisc
if (entry) {
tcx_miniq_set_active(entry, false);
if (!tcx_entry_is_active(entry)) {
- tcx_entry_update(dev, NULL, false);
+ RCU_INIT_POINTER(dev->tcx_ingress, NULL);
tcx_entry_free(entry);
}
}
--

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+bdcf14...@syzkaller.appspotmail.com

Tested on:

commit: 2542a961 tcx: Fix splat in ingress_destroy upon tcx_en..
git tree: https://github.com/cilium/linux.git pr/new-api-tcx8
console output: https://syzkaller.appspot.com/x/log.txt?x=174dd99ea80000
kernel config: https://syzkaller.appspot.com/x/.config?x=23b50c2e795c7120

dashboard link: https://syzkaller.appspot.com/bug?extid=bdcf141f362ef83335cf
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.
Note: testing is done by a robot and is best-effort only.

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+bdcf14...@syzkaller.appspotmail.com

Tested on:

commit: 03b123de tcp: tcp_enter_quickack_mode() should be static
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git
console output: https://syzkaller.appspot.com/x/log.txt?x=143f7cd6a80000
kernel config: https://syzkaller.appspot.com/x/.config?x=32e3dcc11fd0d297

dashboard link: https://syzkaller.appspot.com/bug?extid=bdcf141f362ef83335cf
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=15bf3a52a80000

[syzbot]

syzbot has bisected this issue to:

commit e420bed025071a623d2720a92bc2245c84757ecb
Author: Daniel Borkmann <dan...@iogearbox.net>
Date: Wed Jul 19 14:08:52 2023 +0000

bpf: Add fd-based tcx multi-prog infra with link support

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1568abf4a80000
start commit: 03b123debcbc tcp: tcp_enter_quickack_mode() should be static
git tree: net-next
final oops: https://syzkaller.appspot.com/x/report.txt?x=1768abf4a80000
console output: https://syzkaller.appspot.com/x/log.txt?x=1368abf4a80000

kernel config: https://syzkaller.appspot.com/x/.config?x=32e3dcc11fd0d297
dashboard link: https://syzkaller.appspot.com/bug?extid=bdcf141f362ef83335cf

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10bf2bf4a80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12741e9aa80000

Reported-by: syzbot+bdcf14...@syzkaller.appspotmail.com
Fixes: e420bed02507 ("bpf: Add fd-based tcx multi-prog infra with link support")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection