[syzbot] [bpf?] WARNING in free_mem_alloc_no_barrier

[syzbot] [bpf?] WARNING in free_mem_alloc_no_barrier

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    c32f8dc5aaf9 Merge branch 'for-next/core' into for-kernelci
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=15a66cf4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=ea4635ffd6ad5b4a
dashboard link: https://syzkaller.appspot.com/bug?extid=ba09f1d8f92da05bd539
compiler:       Debian clang version 20.1.2 (++20250402124445+58df0ef89dd6-1~exp1~20250402004600.97), Debian LLD 20.1.2
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/b921498959d4/disk-c32f8dc5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/04e6ad946c4b/vmlinux-c32f8dc5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d4f0d8db50ee/Image-c32f8dc5.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ba09f1d8f92da05bd539@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 113 at kernel/bpf/memalloc.c:649 check_mem_cache kernel/bpf/memalloc.c:649 [inline]
WARNING: CPU: 1 PID: 113 at kernel/bpf/memalloc.c:649 check_leaked_objs kernel/bpf/memalloc.c:667 [inline]
WARNING: CPU: 1 PID: 113 at kernel/bpf/memalloc.c:649 free_mem_alloc_no_barrier+0x204/0x514 kernel/bpf/memalloc.c:683
Modules linked in:
CPU: 1 UID: 0 PID: 113 Comm: kworker/u8:4 Not tainted 6.15.0-rc5-syzkaller-gc32f8dc5aaf9 #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events_unbound free_mem_alloc_deferred
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : check_mem_cache kernel/bpf/memalloc.c:649 [inline]
pc : check_leaked_objs kernel/bpf/memalloc.c:667 [inline]
pc : free_mem_alloc_no_barrier+0x204/0x514 kernel/bpf/memalloc.c:683
lr : check_mem_cache kernel/bpf/memalloc.c:649 [inline]
lr : check_leaked_objs kernel/bpf/memalloc.c:667 [inline]
lr : free_mem_alloc_no_barrier+0x204/0x514 kernel/bpf/memalloc.c:683
sp : ffff80009b427a10
x29: ffff80009b427a20 x28: ffffffffffffffff x27: 0000000000000000
x26: ffff80008ec24258 x25: ffff80008ec24258 x24: dfff800000000000
x23: fffffdffbf6e0ce8 x22: fffffdffbf6e0c40 x21: 1ffff00011d8484b
x20: ffff0000f0b02f08 x19: ffff0000f0b02f00 x18: 1fffe00033871676
x17: ffff80010d12e000 x16: ffff80008adb421c x15: 0000000000000001
x14: 1ffff00013684f24 x13: 0000000000000000 x12: 0000000000000000
x11: ffff700013684f25 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : ffff0000c55d1e80 x7 : ffff80008adc3498 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000001 x3 : ffff80008adc37ac
x2 : 0000000000000001 x1 : 0000000000000003 x0 : 0000000000000000
Call trace:
 check_mem_cache kernel/bpf/memalloc.c:649 [inline] (P)
 check_leaked_objs kernel/bpf/memalloc.c:667 [inline] (P)
 free_mem_alloc_no_barrier+0x204/0x514 kernel/bpf/memalloc.c:683 (P)
 free_mem_alloc kernel/bpf/memalloc.c:706 [inline]
 free_mem_alloc_deferred+0x2c/0x1a4 kernel/bpf/memalloc.c:713
 process_one_work+0x7e8/0x156c kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x958/0xed8 kernel/workqueue.c:3400
 kthread+0x5fc/0x75c kernel/kthread.c:464
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:847
irq event stamp: 254062
hardirqs last  enabled at (254061): [<ffff80008add4c80>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline]
hardirqs last  enabled at (254061): [<ffff80008add4c80>] _raw_spin_unlock_irq+0x30/0x80 kernel/locking/spinlock.c:202
hardirqs last disabled at (254062): [<ffff80008adaf5e0>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:511
softirqs last  enabled at (253980): [<ffff800086383a80>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last  enabled at (253980): [<ffff800086383a80>] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline]
softirqs last  enabled at (253980): [<ffff800086383a80>] nsim_dev_trap_report_work+0x67c/0x9fc drivers/net/netdevsim/dev.c:851
softirqs last disabled at (253978): [<ffff8000863839f8>] spin_lock_bh include/linux/spinlock.h:356 [inline]
softirqs last disabled at (253978): [<ffff8000863839f8>] nsim_dev_trap_report drivers/net/netdevsim/dev.c:816 [inline]
softirqs last disabled at (253978): [<ffff8000863839f8>] nsim_dev_trap_report_work+0x5f4/0x9fc drivers/net/netdevsim/dev.c:851
---[ end trace 0000000000000000 ]---


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