==================================================================
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 ffffc9000439f920 by task syz.3.1244/13134

CPU: 1 UID: 0 PID: 13134 Comm: syz.3.1244 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:ffffc9000410f778 EFLAGS: 00000286
RAX: 796a90760cae1c00 RBX: 0000000000000000 RCX: 796a90760cae1c00
RDX: 0000000000000007 RSI: ffffffff8d992cd0 RDI: ffffffff8be31d00
RBP: ffffc9000410f7d0 R08: ffffffff8fa17437 R09: 1ffffffff1f42e86
R10: dffffc0000000000 R11: fffffbfff1f42e87 R12: ffff88802e2e8000
R13: dffffc0000000000 R14: ffff88801cee5a00 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:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 4b 97 02 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000410fb68 EFLAGS: 00000206
RAX: 796a90760cae1c00 RBX: 0000000000000000 RCX: 796a90760cae1c00
RDX: 0000000000000000 RSI: ffffffff8db80a8e RDI: ffffffff8be31d00
RBP: ffffffff820c56a0 R08: 0000000000000000 R09: ffffffff820c56a0
R10: dffffc0000000000 R11: fffff52000821ecd R12: 0000000000000001
R13: ffff88801a471760 R14: 0000000000000001 R15: 0000000000000246
 __might_fault+0xcc/0x130 mm/memory.c:6967
 do_recvmmsg+0x330/0x770 net/socket.c:2977
 __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: 0033:0x7f4c4d38e929
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:00007f4c4e1f7038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f4c4d5b6080 RCX: 00007f4c4d38e929
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000004
RBP: 00007f4c4d410b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f4c4d5b6080 R15: 00007fffde68d7a8
 </TASK>

The buggy address belongs to the virtual mapping at
 [ffffc90004398000, ffffc900043a1000) 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:0xa1 pfn:0x78143
memcg:ffff888028c11d82
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: 00000000000000a1 0000000000000000 00000001ffffffff ffff888028c11d82
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 5839, tgid 5839 (syz-executor), ts 954008987818, free_ts 942567649389
 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_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 12464 tgid 12464 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
 vfree+0x25a/0x400 mm/vmalloc.c:3434
 kcov_put kernel/kcov.c:439 [inline]
 kcov_close+0x28/0x50 kernel/kcov.c:535
 __fput+0x449/0xa70 fs/file_table.c:468
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x6b5/0x2300 kernel/exit.c:959
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1100
 get_signal+0x1286/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffffc9000439f800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9000439f880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc9000439f900: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 00
                                  ^
 ffffc9000439f980: 00 00 00 f3 f3 f3 f3 f3 00 00 00 00 00 00 00 00
 ffffc9000439fa00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
----------------
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