R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffd3b7486cf R14: 00007fec5b6e1300 R15: 0000000000022000 ================================================================== BUG: KASAN: slab-use-after-free in flush_tlb_func+0x24d/0x560 Write of size 8 at addr ffff888016cc7a40 by task syz-executor.1/15173 CPU: 1 UID: 0 PID: 15173 Comm: syz-executor.1 Not tainted 6.16.0-rc4-next-20250701 #1 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack_lvl+0xca/0x120 print_report+0xcb/0x670 kasan_report+0xca/0x100 kasan_check_range+0x37/0x1a0 flush_tlb_func+0x24d/0x560 __flush_smp_call_function_queue+0x20d/0x740 __sysvec_call_function_single+0x6d/0x360 sysvec_call_function_single+0x5f/0xc0 asm_sysvec_call_function_single+0x1a/0x20 RIP: 0010:handle_softirqs+0x174/0x770 Code: c8 83 83 3c 0a 00 00 01 c7 44 24 20 0a 00 00 00 48 89 44 24 18 65 66 c7 05 cf 84 47 06 00 00 e8 22 65 40 00 fb bb ff ff ff ff <48> c7 c5 c0 c0 a0 85 41 0f bc de 83 c3 01 0f 85 9b 00 00 00 e9 8d RSP: 0018:ffff88806cf08f78 EFLAGS: 00000202 RAX: 000000000000037a RBX: 00000000ffffffff RCX: 0000000000000004 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff813b5b6e RBP: ffff88801d5af968 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff86438657 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000202 R15: 0000000000000000 __irq_exit_rcu+0xc4/0x100 irq_exit_rcu+0x9/0x20 sysvec_apic_timer_interrupt+0x70/0x80 asm_sysvec_apic_timer_interrupt+0x1a/0x20 RIP: 0010:dump_stack_lvl+0x115/0x120 Code: fc ff ff 4c 89 e2 31 f6 31 ff e8 e6 50 7b fc e8 d1 07 a5 fc 48 89 ee 31 ff e8 d7 a5 c4 fc e8 72 aa c4 fc e8 7d d4 cc fc fb 5b <5d> 41 5c e9 63 aa c4 fc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffff88801d5afa10 EFLAGS: 00000206 RAX: 0000000000000377 RBX: ffffffff85d01f20 RCX: 0000000000000040 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff84aeec13 RBP: 0000000000000200 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff86438657 R11: 0000000000000001 R12: ffffffff8530f500 R13: ffffffff85d01f30 R14: 0000000000000000 R15: 0000000000000000 should_fail_ex+0x4d7/0x5e0 should_failslab+0xc2/0x120 __kvmalloc_node_noprof+0x10d/0x5a0 seq_read_iter+0x825/0x1310 seq_read+0x381/0x4c0 proc_reg_read+0x22e/0x310 vfs_read+0x1eb/0xbe0 __x64_sys_pread64+0x1f1/0x260 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fec5e16bb19 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fec5b6e1188 EFLAGS: 00000246 ORIG_RAX: 0000000000000011 RAX: ffffffffffffffda RBX: 00007fec5e27ef60 RCX: 00007fec5e16bb19 RDX: 0000000000019002 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00007fec5b6e11d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffd3b7486cf R14: 00007fec5b6e1300 R15: 0000000000022000 Allocated by task 280: kasan_save_stack+0x24/0x50 kasan_save_track+0x14/0x30 __kasan_slab_alloc+0x59/0x70 kmem_cache_alloc_noprof+0x13e/0x470 copy_process+0x6f3a/0x73e0 kernel_clone+0xea/0x820 __do_sys_clone+0xce/0x120 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 15168: kasan_save_stack+0x24/0x50 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3c/0x90 __kasan_slab_free+0x3c/0x60 kmem_cache_free+0x2a5/0x460 mmput+0x305/0x390 do_exit+0x79d/0x2970 do_group_exit+0xd3/0x2a0 __x64_sys_exit_group+0x3e/0x50 x64_sys_call+0xf76/0x18a0 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888016cc70c0 which belongs to the cache mm_struct of size 2456 The buggy address is located 2432 bytes inside of freed 2456-byte region [ffff888016cc70c0, ffff888016cc7a58) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x16cc0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff8880099ee401 flags: 0x100000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0100000000000040 ffff888008c4bc80 dead000000000100 dead000000000122 raw: 0000000000000000 00000000000c000c 00000000f5000000 ffff8880099ee401 head: 0100000000000040 ffff888008c4bc80 dead000000000100 dead000000000122 head: 0000000000000000 00000000000c000c 00000000f5000000 ffff8880099ee401 head: 0100000000000003 ffffea00005b3001 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888016cc7900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888016cc7980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888016cc7a00: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ^ ffff888016cc7a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888016cc7b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== FAULT_INJECTION: forcing a failure. name fail_usercopy, interval 1, probability 0, space 0, times 0 CPU: 1 UID: 0 PID: 15189 Comm: syz-executor.1 Tainted: G B 6.16.0-rc4-next-20250701 #1 PREEMPT(voluntary) Tainted: [B]=BAD_PAGE Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack_lvl+0xfa/0x120 should_fail_ex+0x4d7/0x5e0 _copy_to_iter+0x578/0x15b0 seq_read_iter+0xdc3/0x1310 seq_read+0x381/0x4c0 proc_reg_read+0x22e/0x310 vfs_read+0x1eb/0xbe0 __x64_sys_pread64+0x1f1/0x260 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fec5e16bb19 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fec5b6e1188 EFLAGS: 00000246 ORIG_RAX: 0000000000000011 RAX: ffffffffffffffda RBX: 00007fec5e27ef60 RCX: 00007fec5e16bb19 RDX: 0000000000019002 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00007fec5b6e11d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffd3b7486cf R14: 00007fec5b6e1300 R15: 0000000000022000 FAULT_INJECTION: forcing a failure. name fail_page_alloc, interval 1, probability 0, space 0, times 0 CPU: 1 UID: 0 PID: 15209 Comm: syz-executor.1 Tainted: G B 6.16.0-rc4-next-20250701 #1 PREEMPT(voluntary) Tainted: [B]=BAD_PAGE Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: dump_stack_lvl+0xfa/0x120 should_fail_ex+0x4d7/0x5e0 should_fail_alloc_page+0xe0/0x110 prepare_alloc_pages+0x1af/0x500 __alloc_frozen_pages_noprof+0x17f/0x1f10 alloc_pages_mpol+0xed/0x340 vma_alloc_folio_noprof+0xe9/0x440 __handle_mm_fault+0x142c/0x30f0 handle_mm_fault+0x2c3/0x900 do_user_addr_fault+0x395/0xeb0 exc_page_fault+0xb0/0x180 asm_exc_page_fault+0x26/0x30 RIP: 0010:rep_movs_alternative+0x33/0x90 Code: 73 25 85 c9 74 0f 8a 06 88 07 48 ff c7 48 ff c6 48 ff c9 75 f1 e9 ad 87 03 00 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 8b 06 <48> 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 db 83 f9 08 73 e8 eb RSP: 0018:ffff88801aae79d0 EFLAGS: 00050202 RAX: 6c616e6f73726550 RBX: 0000000000000028 RCX: 0000000000000028 RDX: ffffed100800ac05 RSI: ffff888040056000 RDI: 0000000020000100 RBP: 0000000000000028 R08: 0000000000000000 R09: ffffed100800ac04 R10: ffff888040056027 R11: 203a736563697665 R12: 0000000020000100 R13: ffff88801aae7be8 R14: ffff888040056000 R15: 0000000000000000 _copy_to_iter+0x48d/0x15b0 seq_read_iter+0xdc3/0x1310 seq_read+0x381/0x4c0 proc_reg_read+0x22e/0x310 vfs_read+0x1eb/0xbe0 __x64_sys_pread64+0x1f1/0x260 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fec5e16bb19 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fec5b6e1188 EFLAGS: 00000246 ORIG_RAX: 0000000000000011 RAX: ffffffffffffffda RBX: 00007fec5e27ef60 RCX: 00007fec5e16bb19 RDX: 0000000000019002 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00007fec5b6e11d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffd3b7486cf R14: 00007fec5b6e1300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: c8 83 83 3c enterq $0x8383,$0x3c 4: 0a 00 or (%rax),%al 6: 00 01 add %al,(%rcx) 8: c7 44 24 20 0a 00 00 movl $0xa,0x20(%rsp) f: 00 10: 48 89 44 24 18 mov %rax,0x18(%rsp) 15: 65 66 c7 05 cf 84 47 movw $0x0,%gs:0x64784cf(%rip) # 0x64784ee 1c: 06 00 00 1f: e8 22 65 40 00 callq 0x406546 24: fb sti 25: bb ff ff ff ff mov $0xffffffff,%ebx * 2a: 48 c7 c5 c0 c0 a0 85 mov $0xffffffff85a0c0c0,%rbp <-- trapping instruction 31: 41 0f bc de bsf %r14d,%ebx 35: 83 c3 01 add $0x1,%ebx 38: 0f 85 9b 00 00 00 jne 0xd9 3e: e9 .byte 0xe9 3f: 8d .byte 0x8d