syzbot

==================================================================
BUG: KASAN: slab-use-after-free in instrument_atomic_write include/linux/instrumented.h:82 [inline]
BUG: KASAN: slab-use-after-free in clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline]
BUG: KASAN: slab-use-after-free in cpumask_clear_cpu include/linux/cpumask.h:628 [inline]
BUG: KASAN: slab-use-after-free in flush_tlb_func+0x23d/0x6c0 arch/x86/mm/tlb.c:1132
Write of size 8 at addr ffff8880304c14c0 by task swapper/0/0

CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.16.0-rc4-next-20250702-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xd2/0x2b0 mm/kasan/report.c:521
 kasan_report+0x118/0x150 mm/kasan/report.c:634
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:189
 instrument_atomic_write include/linux/instrumented.h:82 [inline]
 clear_bit include/asm-generic/bitops/instrumented-atomic.h:41 [inline]
 cpumask_clear_cpu include/linux/cpumask.h:628 [inline]
 flush_tlb_func+0x23d/0x6c0 arch/x86/mm/tlb.c:1132
 csd_do_func kernel/smp.c:134 [inline]
 __flush_smp_call_function_queue+0x370/0xaa0 kernel/smp.c:540
 __sysvec_call_function_single+0xa8/0x3d0 arch/x86/kernel/smp.c:271
 instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline]
 sysvec_call_function_single+0x4f/0xc0 arch/x86/kernel/smp.c:266
 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709
RIP: 0010:variable_ffs arch/x86/include/asm/bitops.h:318 [inline]
RIP: 0010:handle_softirqs+0x1b0/0x870 kernel/softirq.c:567
Code: 89 64 24 30 0f b7 db 48 c7 c7 a0 99 89 8b e8 87 55 f1 09 65 66 c7 05 c5 4e 3e 11 00 00 e8 f8 55 42 00 fb 49 c7 c7 c0 c0 00 8e <b8> ff ff ff ff 0f bc c3 41 89 c5 41 ff c5 0f 84 c2 03 00 00 89 5c
RSP: 0018:ffffc90000007e40 EFLAGS: 00000286
RAX: be8be6e4e2e52700 RBX: 0000000000000382 RCX: be8be6e4e2e52700
RDX: 0000000000000000 RSI: ffffffff8da6993f RDI: ffffffff8be4b100
RBP: ffffc90000007f50 R08: ffffffff8fc29e37 R09: 1ffffffff1f853c6
R10: dffffc0000000000 R11: fffffbfff1f853c7 R12: 000000000000000a
R13: 0000000000000000 R14: dffffc0000000000 R15: ffffffff8e00c0c0
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 83 86 11 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8e007d80 EFLAGS: 000002c6
RAX: be8be6e4e2e52700 RBX: ffffffff81971188 RCX: be8be6e4e2e52700
RDX: 0000000000000001 RSI: ffffffff8da6993f RDI: ffffffff8be4b100
RBP: ffffffff8e007ea8 R08: ffff8880b8632f1b R09: 1ffff110170c65e3
R10: dffffc0000000000 R11: ffffed10170c65e4 R12: ffffffff8fc29e30
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1c12a50
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:757
 default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:190 [inline]
 do_idle+0x1e8/0x510 kernel/sched/idle.c:330
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
 rest_init+0x2de/0x300 init/main.c:744
 start_kernel+0x47d/0x500 init/main.c:1097
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307
 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288
 common_startup_64+0x13e/0x147
 </TASK>

Allocated by task 6776:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4180 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236
 dup_mm kernel/fork.c:1466 [inline]
 copy_mm+0xdb/0x4b0 kernel/fork.c:1528
 copy_process+0x1706/0x3c00 kernel/fork.c:2168
 kernel_clone+0x21e/0x870 kernel/fork.c:2598
 __do_sys_clone kernel/fork.c:2741 [inline]
 __se_sys_clone kernel/fork.c:2725 [inline]
 __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2725
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 10396:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2417 [inline]
 slab_free mm/slub.c:4680 [inline]
 kmem_cache_free+0x18f/0x400 mm/slub.c:4782
 exit_mm+0x1da/0x2c0 kernel/exit.c:581
 do_exit+0x648/0x2300 kernel/exit.c:947
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1100
 __do_sys_exit_group kernel/exit.c:1111 [inline]
 __se_sys_exit_group kernel/exit.c:1109 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1109
 x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8880304c0ac0
 which belongs to the cache mm_struct of size 2584
The buggy address is located 2560 bytes inside of
 freed 2584-byte region [ffff8880304c0ac0, ffff8880304c14d8)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880304c2040 pfn:0x304c0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88807e8f9981
ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801a84bb40 ffffea0000a9fe00 dead000000000003
raw: ffff8880304c2040 00000000800b000a 00000000f5000000 ffff88807e8f9981
head: 00fff00000000040 ffff88801a84bb40 ffffea0000a9fe00 dead000000000003
head: ffff8880304c2040 00000000800b000a 00000000f5000000 ffff88807e8f9981
head: 00fff00000000003 ffffea0000c13001 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5207, tgid 5207 (udevd), ts 34556555944, free_ts 34542670636
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1848
 prep_new_page mm/page_alloc.c:1856 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3855
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5145
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2487 [inline]
 allocate_slab+0x8a/0x370 mm/slub.c:2655
 new_slab mm/slub.c:2709 [inline]
 ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891
 __slab_alloc mm/slub.c:3981 [inline]
 __slab_alloc_node mm/slub.c:4056 [inline]
 slab_alloc_node mm/slub.c:4217 [inline]
 kmem_cache_alloc_noprof+0x283/0x3c0 mm/slub.c:4236
 dup_mm kernel/fork.c:1466 [inline]
 copy_mm+0xdb/0x4b0 kernel/fork.c:1528
 copy_process+0x1706/0x3c00 kernel/fork.c:2168
 kernel_clone+0x21e/0x870 kernel/fork.c:2598
 __do_sys_clone kernel/fork.c:2741 [inline]
 __se_sys_clone kernel/fork.c:2725 [inline]
 __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2725
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5214 tgid 5214 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1392 [inline]
 __free_frozen_pages+0xb80/0xd80 mm/page_alloc.c:2892
 discard_slab mm/slub.c:2753 [inline]
 __put_partials+0x156/0x1a0 mm/slub.c:3218
 put_cpu_partial+0x17c/0x250 mm/slub.c:3293
 __slab_free+0x2d5/0x3c0 mm/slub.c:4550
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4180 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236
 getname_flags+0xb8/0x540 fs/namei.c:146
 do_readlinkat+0xbc/0x500 fs/stat.c:575
 __do_sys_readlink fs/stat.c:613 [inline]
 __se_sys_readlink fs/stat.c:610 [inline]
 __x64_sys_readlink+0x7f/0x90 fs/stat.c:610
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff8880304c1380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880304c1400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880304c1480: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc
                                           ^
 ffff8880304c1500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880304c1580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
Code disassembly (best guess):
   0:	89 64 24 30          	mov    %esp,0x30(%rsp)
   4:	0f b7 db             	movzwl %bx,%ebx
   7:	48 c7 c7 a0 99 89 8b 	mov    $0xffffffff8b8999a0,%rdi
   e:	e8 87 55 f1 09       	call   0x9f1559a
  13:	65 66 c7 05 c5 4e 3e 	movw   $0x0,%gs:0x113e4ec5(%rip)        # 0x113e4ee2
  1a:	11 00 00
  1d:	e8 f8 55 42 00       	call   0x42561a
  22:	fb                   	sti
  23:	49 c7 c7 c0 c0 00 8e 	mov    $0xffffffff8e00c0c0,%r15
* 2a:	b8 ff ff ff ff       	mov    $0xffffffff,%eax <-- trapping instruction
  2f:	0f bc c3             	bsf    %ebx,%eax
  32:	41 89 c5             	mov    %eax,%r13d
  35:	41 ff c5             	inc    %r13d
  38:	0f 84 c2 03 00 00    	je     0x400
  3e:	89                   	.byte 0x89
  3f:	5c                   	pop    %rsp