[moderation/CI] Re: xsk: introduce pre-allocated memory per xsk CQ

[syzbot ci]

syzbot ci has tested the following series

[v1] xsk: introduce pre-allocated memory per xsk CQ
https://lore.kernel.org/all/20251209085950.9623...@gmail.com
* [PATCH bpf-next v1 1/2] xsk: introduce local_cq for each af_xdp socket
* [PATCH bpf-next v1 2/2] xsk: introduce a dedicated local completion queue for each xsk

and found the following issue:
WARNING in vfree

Full report is available here:
https://ci.syzbot.org/series/5df45d2b-41d6-4675-b3ad-4503516a9ae1

***

WARNING in vfree

tree: bpf-next
URL: https://kernel.googlesource.com/pub/scm/linux/kernel/git/bpf/bpf-next.git
base: 835a50753579aa8368a08fca307e638723207768
arch: amd64
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
config: https://ci.syzbot.org/builds/726617c2-a613-4879-9987-91e65545dba1/config
C repro: https://ci.syzbot.org/findings/0c82a0b1-8cb3-49ae-9fbe-fa3bd02c2ba0/c_repro
syz repro: https://ci.syzbot.org/findings/0c82a0b1-8cb3-49ae-9fbe-fa3bd02c2ba0/syz_repro

------------[ cut here ]------------
Trying to vfree() nonexistent vm area (ffffc900034e6000)
WARNING: mm/vmalloc.c:3423 at 0x0, CPU#0: syz.0.19/5983
Modules linked in:
CPU: 0 UID: 0 PID: 5983 Comm: syz.0.19 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:vfree+0x393/0x400 mm/vmalloc.c:3422
Code: e8 72 1d ab ff 4c 89 f7 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d e9 0c fa ff ff e8 57 1d ab ff 48 8d 3d 10 fc 6e 0d 4c 89 f6 <67> 48 0f b9 3a e9 fd fd ff ff e8 3e 1d ab ff 4c 89 e7 e8 66 00 00
RSP: 0018:ffffc90004e37c40 EFLAGS: 00010293
RAX: ffffffff82162d09 RBX: 0000000000000000 RCX: ffff88816c66d7c0
RDX: 0000000000000000 RSI: ffffc900034e6000 RDI: ffffffff8f852920
RBP: 1ffff1102289d8bf R08: ffff88810005f1bb R09: 1ffff1102000be37
R10: dffffc0000000000 R11: ffffed102000be38 R12: ffff88801eed1818
R13: dffffc0000000000 R14: ffffc900034e6000 R15: ffff8881144ec608
FS: 0000555574db2500(0000) GS:ffff88818eab1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000000c0 CR3: 0000000112a48000 CR4: 00000000000006f0
Call Trace:
<TASK>
xsk_clear_local_cq net/xdp/xsk.c:1188 [inline]
xsk_release+0x6b3/0x880 net/xdp/xsk.c:1220
__sock_release net/socket.c:653 [inline]
sock_close+0xc3/0x240 net/socket.c:1446
__fput+0x44c/0xa70 fs/file_table.c:468
task_work_run+0x1d4/0x260 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
exit_to_user_mode_loop+0xff/0x4f0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7eff8518f7c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd6ca61b78 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000001253b RCX: 00007eff8518f7c9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000001 R09: 000000086ca61e6f
R10: 0000001b2f920000 R11: 0000000000000246 R12: 00007eff853e5fac
R13: 00007eff853e5fa0 R14: ffffffffffffffff R15: 0000000000000003
</TASK>
----------------
Code disassembly (best guess):
0: e8 72 1d ab ff call 0xffab1d77
5: 4c 89 f7 mov %r14,%rdi
8: 48 83 c4 18 add $0x18,%rsp
c: 5b pop %rbx
d: 41 5c pop %r12
f: 41 5d pop %r13
11: 41 5e pop %r14
13: 41 5f pop %r15
15: 5d pop %rbp
16: e9 0c fa ff ff jmp 0xfffffa27
1b: e8 57 1d ab ff call 0xffab1d77
20: 48 8d 3d 10 fc 6e 0d lea 0xd6efc10(%rip),%rdi # 0xd6efc37
27: 4c 89 f6 mov %r14,%rsi
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: e9 fd fd ff ff jmp 0xfffffe31
34: e8 3e 1d ab ff call 0xffab1d77
39: 4c 89 e7 mov %r12,%rdi
3c: e8 .byte 0xe8
3d: 66 00 00 data16 add %al,(%rax)


***

If these findings have caused you to resend the series or submit a
separate fix, please add the following tag to your commit message:
Tested-by: syz...@syzkaller.appspotmail.com

---
This report is generated by a bot. It may contain errors.
syzbot ci engineers can be reached at syzk...@googlegroups.com.

The email will later be sent to:
[a...@kernel.org bj...@kernel.org b...@vger.kernel.org dan...@iogearbox.net da...@davemloft.net edum...@google.com ha...@kernel.org john.fa...@gmail.com jonatha...@gmail.com kernelj...@gmail.com kerne...@tencent.com ku...@kernel.org maciej.fi...@intel.com magnus....@intel.com net...@vger.kernel.org pab...@redhat.com s...@fomichev.me]

If the report looks fine to you, reply with:
#syz upstream

[Aleksandr Nogikh]

#syz upstream

> --
> You received this message because you are subscribed to the Google Groups "syzkaller-upstream-moderation" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-upstream-m...@googlegroups.com.
> To view this discussion visit https://groups.google.com/d/msgid/syzkaller-upstream-moderation/69382102.a70a0220.104cf0.0003.GAE%40google.com.

[syzbot ci]

syzbot ci has tested the following series

[v2] xsk: introduce pre-allocated memory per xsk CQ
https://lore.kernel.org/all/20251216052623.269...@gmail.com
* [PATCH bpf-next v2 1/2] xsk: introduce local_cq for each af_xdp socket
* [PATCH bpf-next v2 2/2] xsk: introduce a dedicated local completion queue for each xsk

and found the following issue:
WARNING in vfree

Full report is available here:

https://ci.syzbot.org/series/6719e0f5-2213-4ff5-83d4-c964705b4b0f

***

WARNING in vfree

tree: bpf-next
URL: https://kernel.googlesource.com/pub/scm/linux/kernel/git/bpf/bpf-next.git

base: 759377dab35e404fc4f013e3f853d6e9450b4633

arch: amd64
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

config: https://ci.syzbot.org/builds/99fbc71e-e7da-4091-b3a0-9180ab35952e/config
C repro: https://ci.syzbot.org/findings/9588a511-f24a-4f1a-a73b-01059171d1d7/c_repro
syz repro: https://ci.syzbot.org/findings/9588a511-f24a-4f1a-a73b-01059171d1d7/syz_repro

UDPLite6: UDP-Lite is deprecated and scheduled to be removed in 2025, please contact the netdev mailing list
------------[ cut here ]------------
Trying to vfree() nonexistent vm area (ffffc900028f6000)
WARNING: mm/vmalloc.c:3423 at 0x0, CPU#1: syz.0.17/5994
Modules linked in:
CPU: 1 UID: 0 PID: 5994 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)

Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:vfree+0x393/0x400 mm/vmalloc.c:3422

Code: e8 42 12 ab ff 4c 89 f7 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d e9 0c fa ff ff e8 27 12 ab ff 48 8d 3d e0 f1 6e 0d 4c 89 f6 <67> 48 0f b9 3a e9 fd fd ff ff e8 0e 12 ab ff 4c 89 e7 e8 66 00 00
RSP: 0018:ffffc900043d7c40 EFLAGS: 00010293
RAX: ffffffff82163839 RBX: 0000000000000000 RCX: ffff888112303a80
RDX: 0000000000000000 RSI: ffffc900028f6000 RDI: ffffffff8f852a20
RBP: 1ffff1102e7044bf R08: ffff88810005d863 R09: 1ffff1102000bb0c
R10: dffffc0000000000 R11: ffffed102000bb0d R12: ffff888118dc8018
R13: dffffc0000000000 R14: ffffc900028f6000 R15: ffff888173822608
FS: 0000555558e99500(0000) GS:ffff8882a9eb0000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 0000200000000180 CR3: 0000000174424000 CR4: 00000000000006f0
Call Trace:
<TASK>
xsk_clear_local_cq net/xdp/xsk.c:1194 [inline]
xsk_release+0x6b3/0x880 net/xdp/xsk.c:1226

__sock_release net/socket.c:653 [inline]
sock_close+0xc3/0x240 net/socket.c:1446
__fput+0x44c/0xa70 fs/file_table.c:468
task_work_run+0x1d4/0x260 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
exit_to_user_mode_loop+0xff/0x4f0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f

RIP: 0033:0x7f5338b8f7c9

Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48

RSP: 002b:00007ffd8e18db38 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000000f4d1 RCX: 00007f5338b8f7c9

RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003

RBP: 0000000000000000 R08: 0000000000000001 R09: 000000088e18de2f
R10: 0000001b2fe20000 R11: 0000000000000246 R12: 00007f5338de5fac
R13: 00007f5338de5fa0 R14: ffffffffffffffff R15: 0000000000000003

</TASK>
----------------
Code disassembly (best guess):

0: e8 42 12 ab ff call 0xffab1247

5: 4c 89 f7 mov %r14,%rdi
8: 48 83 c4 18 add $0x18,%rsp
c: 5b pop %rbx
d: 41 5c pop %r12
f: 41 5d pop %r13
11: 41 5e pop %r14
13: 41 5f pop %r15
15: 5d pop %rbp
16: e9 0c fa ff ff jmp 0xfffffa27

1b: e8 27 12 ab ff call 0xffab1247
20: 48 8d 3d e0 f1 6e 0d lea 0xd6ef1e0(%rip),%rdi # 0xd6ef207

27: 4c 89 f6 mov %r14,%rsi
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: e9 fd fd ff ff jmp 0xfffffe31

34: e8 0e 12 ab ff call 0xffab1247