R10: 0000000000002200 R11: 0000000000000293 R12: 0000000000000004 R13: 0000000000000004 R14: 0000000020000230 R15: 0000000000000002 ================================================================== BUG: KASAN: slab-use-after-free in flush_tlb_func+0x24d/0x560 Write of size 8 at addr ffff88800dd85b80 by task syz-executor.6/23568 CPU: 0 UID: 0 PID: 23568 Comm: syz-executor.6 Not tainted 6.16.0-rc4-next-20250630 #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+0x39/0x1b0 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:ffff88806ce08f78 EFLAGS: 00000202 RAX: 0000000000000138 RBX: 00000000ffffffff RCX: 0000000000000004 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff813b5b6e RBP: ffff88803bc9f958 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff86438657 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000282 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 40 7b fc e8 e1 f7 a4 fc 48 89 ee 31 ff e8 d7 95 c4 fc e8 72 9a c4 fc e8 7d c4 cc fc fb 5b <5d> 41 5c e9 63 9a c4 fc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffff88803bc9fa00 EFLAGS: 00000206 RAX: 0000000000000135 RBX: ffffffff85e964a0 RCX: 0000000000000040 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff84aefc13 RBP: 0000000000000200 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff86438657 R11: 0000000000060190 R12: ffffffff8530f500 R13: ffffffff85e964b0 R14: 0000000000000000 R15: 0000000000000000 should_fail_ex+0x4d7/0x5e0 copy_folio_from_iter_atomic+0x3d3/0x1820 generic_perform_write+0x1e9/0x820 shmem_file_write_iter+0x111/0x140 vfs_write+0xbe9/0x10c0 __x64_sys_pwrite64+0x1f1/0x260 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe8325e9ab7 Code: 08 89 3c 24 48 89 4c 24 18 e8 e5 f8 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 48 8b 74 24 08 8b 3c 24 b8 12 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 04 24 e8 15 f9 ff ff 48 8b RSP: 002b:00007fe82fbabf20 EFLAGS: 00000293 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007fe832680970 RCX: 00007fe8325e9ab7 RDX: 000000000000001d RSI: 0000000020011500 RDI: 0000000000000004 RBP: 0000000000000003 R08: 0000000000000000 R09: ffffffffffffffff R10: 0000000000002200 R11: 0000000000000293 R12: 0000000000000004 R13: 0000000000000004 R14: 0000000020000230 R15: 0000000000000002 loop0: detected capacity change from 0 to 512 Allocated by task 277: kasan_save_stack+0x24/0x50 kasan_save_track+0x14/0x30 EXT4-fs (loop0): VFS: Can't find ext4 filesystem __kasan_slab_alloc+0x59/0x70 kmem_cache_alloc_noprof+0x13c/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 23562: kasan_save_stack+0x24/0x50 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3a/0x60 __kasan_slab_free+0x38/0x50 kmem_cache_free+0x2a1/0x460 mmput+0x305/0x390 do_exit+0x79d/0x2970 do_group_exit+0xd3/0x2a0 get_signal+0x2315/0x2340 arch_do_signal_or_restart+0x80/0x790 exit_to_user_mode_loop+0x8b/0x100 do_syscall_64+0x2f7/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88800dd85200 which belongs to the cache mm_struct of size 2456 The buggy address is located 2432 bytes inside of freed 2456-byte region [ffff88800dd85200, ffff88800dd85b98) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xdd80 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88800e10f001 anon flags: 0x100000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0100000000000040 ffff888008c4bc80 0000000000000000 dead000000000001 raw: 0000000000000000 00000000000c000c 00000000f5000000 ffff88800e10f001 FAULT_INJECTION: forcing a failure. name fail_usercopy, interval 1, probability 0, space 0, times 0 head: 0100000000000040 ffff888008c4bc80 0000000000000000 dead000000000001 CPU: 1 UID: 0 PID: 23573 Comm: syz-executor.3 Not tainted 6.16.0-rc4-next-20250630 #1 PREEMPT(voluntary) 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 strncpy_from_user+0x3b/0x2f0 getname_flags.part.0+0x8d/0x540 getname_flags+0x95/0xe0 do_sys_openat2+0x9f/0x1b0 __x64_sys_openat+0x142/0x200 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1e060f0a04 Code: 84 00 00 00 00 00 44 89 54 24 0c e8 96 f9 ff ff 44 8b 54 24 0c 44 89 e2 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 34 44 89 c7 89 44 24 0c e8 c8 f9 ff ff 8b 44 RSP: 002b:00007f1e036b2ed0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f1e06187970 RCX: 00007f1e060f0a04 RDX: 0000000000000002 RSI: 00007f1e036b3000 RDI: 00000000ffffff9c RBP: 00007f1e036b3000 R08: 0000000000000000 R09: ffffffffffffffff R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002 R13: 0000000000000004 R14: 0000000020000248 R15: 0000000000000003 head: 0000000000000000 00000000000c000c 00000000f5000000 ffff88800e10f001 head: 0100000000000003 ffffea0000376001 00000000ffffffff 00000000ffffffff head: ffff88800dd81f50 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88800dd85a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88800dd85b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88800dd85b80: fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88800dd85c00: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ffff88800dd85c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== loop7: detected capacity change from 0 to 512 loop1: detected capacity change from 0 to 512 EXT4-fs (loop7): VFS: Can't find ext4 filesystem EXT4-fs (loop1): unsupported inode size: 0 EXT4-fs (loop1): blocksize: 2048 EXT4-fs (loop4): unmounting filesystem 00000000-0000-0000-0000-000000000000. FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 0 UID: 0 PID: 23578 Comm: syz-executor.3 Tainted: G B 6.16.0-rc4-next-20250630 #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_failslab+0xc2/0x120 kmem_cache_alloc_noprof+0x5f/0x470 alloc_empty_file+0x58/0x1e0 path_openat+0xe0/0x2880 do_filp_open+0x1e8/0x450 do_sys_openat2+0x104/0x1b0 __x64_sys_openat+0x142/0x200 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1e060f0a04 Code: 84 00 00 00 00 00 44 89 54 24 0c e8 96 f9 ff ff 44 8b 54 24 0c 44 89 e2 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 34 44 89 c7 89 44 24 0c e8 c8 f9 ff ff 8b 44 RSP: 002b:00007f1e036b2ed0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f1e06187970 RCX: 00007f1e060f0a04 RDX: 0000000000000002 RSI: 00007f1e036b3000 RDI: 00000000ffffff9c RBP: 00007f1e036b3000 R08: 0000000000000000 R09: ffffffffffffffff R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002 R13: 0000000000000004 R14: 0000000020000248 R15: 0000000000000003 loop0: detected capacity change from 0 to 512 EXT4-fs (loop0): VFS: Can't find ext4 filesystem loop6: detected capacity change from 0 to 512 loop7: detected capacity change from 0 to 512 EXT4-fs (loop7): VFS: Can't find ext4 filesystem FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 0 UID: 0 PID: 23585 Comm: syz-executor.4 Tainted: G B 6.16.0-rc4-next-20250630 #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_failslab+0xc2/0x120 kmem_cache_alloc_lru_noprof+0x73/0x460 __d_alloc+0x31/0xa10 d_alloc_pseudo+0x1d/0xc0 alloc_file_pseudo+0xbe/0x220 __shmem_file_setup+0x1a7/0x370 alloc_file+0x11c/0x500 __x64_sys_memfd_create+0x193/0x280 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb2e3c28b19 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:00007fb2e119df48 EFLAGS: 00000246 ORIG_RAX: 000000000000013f RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007fb2e3c28b19 RDX: 0000000000004400 RSI: 0000000000000000 RDI: 00007fb2e3c820fb RBP: 0000000000000003 R08: 0000000000002200 R09: ffffffffffffffff R10: 0000000000000003 R11: 0000000000000246 R12: 0000000008100000 R13: 0000000020000100 R14: 0000000000040000 R15: 0000000020012c00 EXT4-fs (loop6): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. loop0: detected capacity change from 0 to 512 EXT4-fs (loop6): unmounting filesystem 00000000-0000-0000-0000-000000000000. EXT4-fs (loop0): VFS: Can't find ext4 filesystem loop2: detected capacity change from 0 to 512 EXT4-fs (loop2): VFS: Can't find ext4 filesystem loop1: detected capacity change from 0 to 512 EXT4-fs (loop1): unsupported inode size: 0 EXT4-fs (loop1): blocksize: 2048 loop5: detected capacity change from 0 to 512 EXT4-fs (loop5): unsupported inode size: 0 EXT4-fs (loop5): blocksize: 2048 loop1: detected capacity change from 0 to 512 loop4: detected capacity change from 0 to 512 loop7: detected capacity change from 0 to 512 loop5: detected capacity change from 0 to 512 EXT4-fs (loop1): unsupported inode size: 0 EXT4-fs (loop1): blocksize: 2048 EXT4-fs (loop5): unsupported inode size: 0 loop3: detected capacity change from 0 to 512 EXT4-fs (loop5): blocksize: 2048 EXT4-fs (loop4): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. EXT4-fs (loop7): VFS: Can't find ext4 filesystem loop2: detected capacity change from 0 to 512 loop0: detected capacity change from 0 to 512 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 UID: 0 PID: 23620 Comm: syz-executor.6 Tainted: G B 6.16.0-rc4-next-20250630 #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_failslab+0xc2/0x120 kmem_cache_alloc_noprof+0x5f/0x470 getname_flags.part.0+0x48/0x540 getname_flags+0x95/0xe0 do_sys_openat2+0x9f/0x1b0 __x64_sys_openat+0x142/0x200 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe8325e9a04 Code: 84 00 00 00 00 00 44 89 54 24 0c e8 96 f9 ff ff 44 8b 54 24 0c 44 89 e2 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 34 44 89 c7 89 44 24 0c e8 c8 f9 ff ff 8b 44 RSP: 002b:00007fe82fbabed0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fe832680970 RCX: 00007fe8325e9a04 RDX: 0000000000000002 RSI: 00007fe82fbac000 RDI: 00000000ffffff9c RBP: 00007fe82fbac000 R08: 0000000000000000 R09: ffffffffffffffff R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000002 R13: 0000000000000004 R14: 0000000020000248 R15: 0000000000000003 EXT4-fs (loop0): VFS: Can't find ext4 filesystem EXT4-fs (loop3): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. EXT4-fs (loop2): VFS: Can't find ext4 filesystem EXT4-fs (loop3): unmounting filesystem 00000000-0000-0000-0000-000000000000. EXT4-fs (loop4): unmounting filesystem 00000000-0000-0000-0000-000000000000. loop5: detected capacity change from 0 to 512 EXT4-fs (loop5): unsupported inode size: 0 EXT4-fs (loop5): blocksize: 2048 ---------------- 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