R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffeec003c2f R14: 00007f5158913300 R15: 0000000000022000 ================================================================== BUG: KASAN: slab-use-after-free in flush_tlb_func+0x24d/0x560 Write of size 8 at addr ffff8880175113c0 by task syz-executor.3/8504 CPU: 0 UID: 0 PID: 8504 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+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: 00000212 RAX: 0000000000000120 RBX: 00000000ffffffff RCX: 0000000000000008 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff813b5b6e RBP: ffff88803f0d7838 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff86438657 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000280 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:ffff88803f0d78e0 EFLAGS: 00000206 RAX: 000000000000011d RBX: ffffffff85d01e20 RCX: 0000000000000080 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff84aefc13 RBP: 0000000000000200 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff86438657 R11: 0000000000000001 R12: ffffffff8530f500 R13: ffffffff85d01e30 R14: 0000000000000000 R15: 0000000000000000 should_fail_ex+0x4d7/0x5e0 should_failslab+0xc2/0x120 kmem_cache_alloc_lru_noprof+0x73/0x460 __d_alloc+0x31/0xa10 d_alloc_parallel+0x112/0x1330 proc_fill_cache+0x2ea/0x470 proc_task_readdir+0x505/0xf80 iterate_dir+0x1e8/0x5f0 __x64_sys_getdents+0x13d/0x2c0 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f515b39db19 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:00007f5158913188 EFLAGS: 00000246 ORIG_RAX: 000000000000004e RAX: ffffffffffffffda RBX: 00007f515b4b0f60 RCX: 00007f515b39db19 RDX: 0000000000000033 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00007f51589131d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffeec003c2f R14: 00007f5158913300 R15: 0000000000022000 Allocated by task 283: kasan_save_stack+0x24/0x50 kasan_save_track+0x14/0x30 __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 8507: 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 ffff888017510a40 which belongs to the cache mm_struct of size 2456 The buggy address is located 2432 bytes inside of freed 2456-byte region [ffff888017510a40, ffff8880175113d8) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x17510 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888012291d01 flags: 0x100000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0100000000000040 ffff888008c4bc80 ffffea000028c000 dead000000000002 raw: 0000000000000000 00000000800c000c 00000000f5000000 ffff888012291d01 head: 0100000000000040 ffff888008c4bc80 ffffea000028c000 dead000000000002 head: 0000000000000000 00000000800c000c 00000000f5000000 ffff888012291d01 head: 0100000000000003 ffffea00005d4401 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888017511280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888017511300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888017511380: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ^ ffff888017511400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888017511480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== loop6: detected capacity change from 0 to 264192 EXT4-fs (loop6): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. EXT4-fs (loop6): unmounting filesystem 00000000-0000-0000-0000-000000000000. loop6: detected capacity change from 0 to 264192 EXT4-fs (loop6): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. loop4: detected capacity change from 0 to 264192 EXT4-fs error (device loop4): __ext4_fill_super:5500: inode #2: comm syz-executor.4: iget: special inode unallocated FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 UID: 0 PID: 8542 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_lru_noprof+0x73/0x460 proc_alloc_inode+0x27/0x210 EXT4-fs (loop6): unmounting filesystem 00000000-0000-0000-0000-000000000000. alloc_inode+0x67/0x250 new_inode+0x1e/0x160 proc_pid_make_inode+0x21/0x170 proc_pid_make_base_inode.constprop.0+0x25/0x190 proc_task_instantiate+0x54/0x1e0 proc_fill_cache+0x367/0x470 proc_task_readdir+0x505/0xf80 iterate_dir+0x1e8/0x5f0 __x64_sys_getdents+0x13d/0x2c0 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f515b39db19 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:00007f5158913188 EFLAGS: 00000246 ORIG_RAX: 000000000000004e RAX: ffffffffffffffda RBX: 00007f515b4b0f60 RCX: 00007f515b39db19 RDX: 0000000000000033 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00007f51589131d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffeec003c2f R14: 00007f5158913300 R15: 0000000000022000 netlink: 4 bytes leftover after parsing attributes in process `syz-executor.7'. EXT4-fs (loop4): get root inode failed EXT4-fs (loop4): mount failed loop6: detected capacity change from 0 to 264192 EXT4-fs (loop6): VFS: Can't find ext4 filesystem loop6: detected capacity change from 0 to 264192 EXT4-fs (loop6): VFS: Can't find ext4 filesystem FAULT_INJECTION: forcing a failure. name fail_usercopy, interval 1, probability 0, space 0, times 0 CPU: 1 UID: 0 PID: 8558 Comm: syz-executor.0 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 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: 0033:0x7fc5d933db19 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:00007fc5d68b3188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fc5d9450f60 RCX: 00007fc5d933db19 RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003 RBP: 00007fc5d68b31d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffe4129bdff R14: 00007fc5d68b3300 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