==================================================================
BUG: KASAN: out-of-bounds in __cpa_flush_tlb+0x46/0x270 arch/x86/mm/pat/set_memory.c:407
Read of size 8 at addr ffffc9000f397920 by task syz.2.598/8403

CPU: 1 UID: 0 PID: 8403 Comm: syz.2.598 Not tainted 6.16.0-rc4-next-20250630-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
 __cpa_flush_tlb+0x46/0x270 arch/x86/mm/pat/set_memory.c:407
 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+0x9e/0xc0 arch/x86/kernel/smp.c:266
 </IRQ>
 <TASK>
 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709
RIP: 0010:finish_task_switch+0x26b/0x950 kernel/sched/core.c:5181
Code: 0f 84 3c 01 00 00 48 85 db 0f 85 63 01 00 00 e9 27 05 00 00 4c 8b 75 d0 4c 89 e7 e8 2f db e0 09 e8 3a 0e 36 00 fb 4c 8b 65 c0 <49> 8d bc 24 18 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0
RSP: 0018:ffffc900109372b8 EFLAGS: 00000286
RAX: 44730f8bb1cd0f00 RBX: 0000000000000000 RCX: 44730f8bb1cd0f00
RDX: 0000000000000006 RSI: ffffffff8d992cd0 RDI: ffffffff8be31d00
RBP: ffffc90010937310 R08: ffffffff8fa17437 R09: 1ffffffff1f42e86
R10: dffffc0000000000 R11: fffffbfff1f42e87 R12: ffff888026d63c00
R13: dffffc0000000000 R14: ffff88801ceada00 R15: ffff8880b873ab18
 context_switch kernel/sched/core.c:5316 [inline]
 __schedule+0x16fd/0x4d00 kernel/sched/core.c:6696
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7019
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307
 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707
RIP: 0010:task_pid include/linux/pid.h:218 [inline]
RIP: 0010:task_active_pid_ns kernel/pid.c:526 [inline]
RIP: 0010:pid_vnr+0x3c/0x1e0 kernel/pid.c:505
Code: bc 00 00 00 00 00 fc ff df e8 20 56 33 00 65 4c 8b 34 25 08 30 a0 92 49 81 c6 40 06 00 00 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 <74> 08 4c 89 f7 e8 fa 69 97 00 4d 8b 36 4d 85 f6 0f 84 9e 00 00 00
RSP: 0018:ffffc900109376a8 EFLAGS: 00000246
RAX: 1ffff11004dac848 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc9000d21c000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc90010937870 R08: ffffc9001093779f R09: 0000000000000000
R10: ffffc90010937780 R11: fffff52002126ef4 R12: dffffc0000000000
R13: 1ffff92002126eec R14: ffff888026d64240 R15: 00000000ffffffff
 scm_set_cred include/net/scm.h:73 [inline]
 __unix_dgram_recvmsg+0x7fa/0xde0 net/unix/af_unix.c:2562
 sock_recvmsg_nosec+0x183/0x1c0 net/socket.c:1065
 ____sys_recvmsg+0x3aa/0x460 net/socket.c:2832
 ___sys_recvmsg+0x1b5/0x510 net/socket.c:2876
 do_recvmmsg+0x307/0x770 net/socket.c:2971
 __sys_recvmmsg net/socket.c:3045 [inline]
 __do_sys_recvmmsg net/socket.c:3068 [inline]
 __se_sys_recvmmsg net/socket.c:3061 [inline]
 __x64_sys_recvmmsg+0x190/0x240 net/socket.c:3061
 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
RIP: 0033:0x7fa424f8e929
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:00007fa425da7038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fa4251b6080 RCX: 00007fa424f8e929
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000006
RBP: 00007fa425010b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fa4251b6080 R15: 00007ffc092110e8
 </TASK>

The buggy address belongs to the virtual mapping at
 [ffffc9000f390000, ffffc9000f399000) created by:
 copy_process+0x54b/0x3c00 kernel/fork.c:1998

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888000000000 pfn:0x32421
memcg:ffff88801fbcce02
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: ffff888000000000 0000000000000000 00000001ffffffff ffff88801fbcce02
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_ZERO|__GFP_NOWARN), pid 8357, tgid 8357 (syz.5.592), ts 292012200962, free_ts 291855206904
 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_frozen_pages_noprof mm/mempolicy.c:2490 [inline]
 alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2510
 vm_area_alloc_pages mm/vmalloc.c:3642 [inline]
 __vmalloc_area_node mm/vmalloc.c:3720 [inline]
 __vmalloc_node_range_noprof+0x97d/0x12f0 mm/vmalloc.c:3893
 __vmalloc_node_noprof+0xc2/0x110 mm/vmalloc.c:3956
 alloc_thread_stack_node kernel/fork.c:310 [inline]
 dup_task_struct+0x3e7/0x860 kernel/fork.c:876
 copy_process+0x54b/0x3c00 kernel/fork.c:1998
 kernel_clone+0x21e/0x870 kernel/fork.c:2598
 __do_sys_clone3 kernel/fork.c:2902 [inline]
 __se_sys_clone3+0x256/0x2d0 kernel/fork.c:2881
 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 6691 tgid 6691 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
 pagetable_free include/linux/mm.h:2896 [inline]
 pagetable_dtor_free include/linux/mm.h:2994 [inline]
 __tlb_remove_table+0x2d2/0x3b0 include/asm-generic/tlb.h:220
 __tlb_remove_table_free mm/mmu_gather.c:227 [inline]
 tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:290
 rcu_do_batch kernel/rcu/tree.c:2582 [inline]
 rcu_core+0xca8/0x1710 kernel/rcu/tree.c:2838
 handle_softirqs+0x286/0x870 kernel/softirq.c:579
 __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_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0xa3/0xc0 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738

Memory state around the buggy address:
 ffffc9000f397800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9000f397880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc9000f397900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                  ^
 ffffc9000f397980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9000f397a00: f1 f1 f1 f1 00 f2 f2 f2 00 f2 f2 f2 00 f3 f3 f3
==================================================================
----------------
Code disassembly (best guess):
   0:	0f 84 3c 01 00 00    	je     0x142
   6:	48 85 db             	test   %rbx,%rbx
   9:	0f 85 63 01 00 00    	jne    0x172
   f:	e9 27 05 00 00       	jmp    0x53b
  14:	4c 8b 75 d0          	mov    -0x30(%rbp),%r14
  18:	4c 89 e7             	mov    %r12,%rdi
  1b:	e8 2f db e0 09       	call   0x9e0db4f
  20:	e8 3a 0e 36 00       	call   0x360e5f
  25:	fb                   	sti
  26:	4c 8b 65 c0          	mov    -0x40(%rbp),%r12
* 2a:	49 8d bc 24 18 16 00 	lea    0x1618(%r12),%rdi <-- trapping instruction
  31:	00
  32:	48 89 f8             	mov    %rdi,%rax
  35:	48 c1 e8 03          	shr    $0x3,%rax
  39:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax
  3e:	84 c0                	test   %al,%al