IPVS: ftp: loaded support on port[0] = 21
IPVS: ftp: loaded support on port[0] = 21
IPVS: ftp: loaded support on port[0] = 21
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 14172 Comm: kworker/u4:7 Not tainted 4.19.143-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:777 [inline]
RIP: 0010:debug_check_no_obj_freed+0x1c9/0x482 lib/debugobjects.c:817
Code: 48 b8 00 01 00 00 00 00 ad de 4d 89 60 08 4c 89 c7 49 89 00 e8 a8 d6 ff ff 09 c3 4d 85 f6 74 2c 4d 89 f0 4c 89 c0 48 c1 e8 03 <42> 80 3c 38 00 0f 84 23 ff ff ff 4c 89 c7 4c 89 44 24 38 e8 4f fb
RSP: 0018:ffff888030ea7a68 EFLAGS: 00010006
RAX: 0e0e000000000000 RBX: 0000000000000000 RCX: ffffffff815256bb
RDX: 1ffffffff17653c3 RSI: 0000000000000004 RDI: ffff88800012f718
RBP: 0000000000000002 R08: 7070000000000000 R09: 0000000000770000
R10: ffffffff8bb29e0b R11: 0000000000000000 R12: dead000000000200
R13: ffff88804f16e000 R14: 7070000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5979dc3740 CR3: 00000000515f0000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 free_pages_prepare mm/page_alloc.c:1055 [inline]
 __free_pages_ok+0x22d/0xd30 mm/page_alloc.c:1278
 slab_destroy mm/slab.c:1713 [inline]
 slabs_destroy+0x90/0xd0 mm/slab.c:1729
 cache_flusharray mm/slab.c:3490 [inline]
 ___cache_free+0x295/0x3a0 mm/slab.c:3532
 qlink_free mm/kasan/quarantine.c:147 [inline]
 qlist_free_all+0x79/0x140 mm/kasan/quarantine.c:166
 quarantine_reduce+0x1a9/0x230 mm/kasan/quarantine.c:259
 kasan_kmalloc+0xa2/0x160 mm/kasan/kasan.c:538
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc mm/slab.c:3397 [inline]
 kmem_cache_alloc+0x110/0x370 mm/slab.c:3557
 prepare_kernel_cred+0x21/0xba0 kernel/cred.c:625
 call_usermodehelper_exec_async+0xb8/0x630 kernel/umh.c:82
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Modules linked in:

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