R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000004 R14: 0000000020000198 R15: 0000000000000001 ================================================================== BUG: KASAN: slab-use-after-free in flush_tlb_func+0x24d/0x560 Write of size 8 at addr ffff888008c665c0 by task syz-executor.7/5601 CPU: 1 UID: 0 PID: 5601 Comm: syz-executor.7 Not tainted 6.16.0-rc4-next-20250702 #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 b4 47 06 00 00 e8 42 6b 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: 00000206 RAX: 00000000000000fc RBX: 00000000ffffffff RCX: 0000000000000004 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff813b5b6e RBP: ffff88801fcaf1d8 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff86439057 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 26 31 7b fc e8 e1 e7 a4 fc 48 89 ee 31 ff e8 f7 8b c4 fc e8 92 90 c4 fc e8 9d ba cc fc fb 5b <5d> 41 5c e9 83 90 c4 fc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffff88801fcaf280 EFLAGS: 00000206 RAX: 00000000000000f9 RBX: ffffffff85d01f60 RCX: 0000000000000040 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff84af0c13 RBP: 0000000000000200 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff86439057 R11: 0000000000000001 R12: ffffffff8530fc40 R13: ffffffff85d01f70 R14: 0000000000000000 R15: 0000000000000000 should_fail_ex+0x4d7/0x5e0 should_failslab+0xc2/0x120 kmem_cache_alloc_noprof+0x5f/0x470 __kernfs_new_node+0xd3/0x870 kernfs_new_node+0x13c/0x1e0 __kernfs_create_file+0x55/0x360 sysfs_add_file_mode_ns+0x21c/0x440 internal_create_group+0x571/0xeb0 loop_configure+0xc64/0x16f0 lo_ioctl+0x1066/0x2780 blkdev_ioctl+0x27c/0x6c0 __x64_sys_ioctl+0x18f/0x210 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f18066a48d7 Code: 3c 1c 48 f7 d8 49 39 c4 72 b8 e8 a4 54 02 00 85 c0 78 bd 48 83 c4 08 4c 89 e0 5b 41 5c c3 0f 1f 44 00 00 b8 10 00 00 00 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:00007f1803c19e98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f18066ee970 RCX: 00007f18066a48d7 RDX: 0000000000000004 RSI: 0000000000004c00 RDI: 0000000000000005 RBP: 0000000000000005 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000004 R14: 0000000020000198 R15: 0000000000000001 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 Allocated by task 290: kasan_save_stack+0x24/0x50 kasan_save_track+0x14/0x30 CPU: 0 UID: 0 PID: 5600 Comm: syz-executor.3 Not tainted 6.16.0-rc4-next-20250702 #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 should_failslab+0xc2/0x120 kmem_cache_alloc_noprof+0x5f/0x470 __kernfs_new_node+0xd3/0x870 kernfs_new_node+0x13c/0x1e0 __kernfs_create_file+0x55/0x360 sysfs_add_file_mode_ns+0x21c/0x440 internal_create_group+0x571/0xeb0 loop_configure+0xc64/0x16f0 lo_ioctl+0x1066/0x2780 blkdev_ioctl+0x27c/0x6c0 __x64_sys_ioctl+0x18f/0x210 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbe9ef228d7 Code: 3c 1c 48 f7 d8 49 39 c4 72 b8 e8 a4 54 02 00 85 c0 78 bd 48 83 c4 08 4c 89 e0 5b 41 5c c3 0f 1f 44 00 00 b8 10 00 00 00 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:00007fbe9c497e98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fbe9ef6c970 RCX: 00007fbe9ef228d7 RDX: 0000000000000004 RSI: 0000000000004c00 RDI: 0000000000000005 RBP: 0000000000000005 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000004 R14: 0000000020000198 R15: 0000000000000001 loop3: detected capacity change from 0 to 1 __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 5597: 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 __x64_sys_exit_group+0x3e/0x50 x64_sys_call+0x18b4/0x18c0 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888008c65c40 which belongs to the cache mm_struct of size 2456 The buggy address is located 2432 bytes inside of freed 2456-byte region [ffff888008c65c40, ffff888008c665d8) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x8c60 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88800bbbe101 flags: 0x100000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0100000000000040 ffff888008c4bc80 ffffea00003c1a00 dead000000000004 raw: 0000000000000000 00000000800c000c 00000000f5000000 ffff88800bbbe101 head: 0100000000000040 ffff888008c4bc80 ffffea00003c1a00 dead000000000004 head: 0000000000000000 00000000800c000c 00000000f5000000 ffff88800bbbe101 head: 0100000000000003 ffffea0000231801 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888008c66480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888008c66500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888008c66580: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ^ ffff888008c66600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888008c66680: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== loop7: detected capacity change from 0 to 1 audit: type=1400 audit(1751480155.652:14): avc: denied { read } for pid=5611 comm="syz-executor.4" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=perf_event permissive=1 loop5: detected capacity change from 0 to 184 loop3: detected capacity change from 0 to 1 isofs_fill_super: bread failed, dev=loop5, iso_blknum=46, block=92 loop7: detected capacity change from 0 to 1 loop6: detected capacity change from 0 to 1 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 0 UID: 0 PID: 5628 Comm: syz-executor.6 Tainted: G B 6.16.0-rc4-next-20250702 #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 __kmalloc_cache_noprof+0x73/0x470 kobject_uevent_env+0x22e/0xf90 loop_configure+0xf4b/0x16f0 lo_ioctl+0x1066/0x2780 blkdev_ioctl+0x27c/0x6c0 __x64_sys_ioctl+0x18f/0x210 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8fc72338d7 Code: 3c 1c 48 f7 d8 49 39 c4 72 b8 e8 a4 54 02 00 85 c0 78 bd 48 83 c4 08 4c 89 e0 5b 41 5c c3 0f 1f 44 00 00 b8 10 00 00 00 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:00007f8fc47a8e98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f8fc727d970 RCX: 00007f8fc72338d7 RDX: 0000000000000004 RSI: 0000000000004c00 RDI: 0000000000000005 RBP: 0000000000000005 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004 R13: 0000000000000004 R14: 0000000020000198 R15: 0000000000000001 ---------------- 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 b4 47 movw $0x0,%gs:0x647b4cf(%rip) # 0x647b4ee 1c: 06 00 00 1f: e8 42 6b 40 00 callq 0x406b66 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