================================================================== BUG: KASAN: slab-use-after-free in ocfs2_fault+0xdb/0x440 fs/ocfs2/mmap.c:41 Read of size 8 at addr ffff88804030c2d8 by task syz.0.2841/18790 CPU: 0 UID: 0 PID: 18790 Comm: syz.0.2841 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xba/0x230 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 ocfs2_fault+0xdb/0x440 fs/ocfs2/mmap.c:41 __do_fault+0x138/0x390 mm/memory.c:5365 do_read_fault mm/memory.c:5800 [inline] do_fault mm/memory.c:5934 [inline] do_pte_missing+0x228f/0x3750 mm/memory.c:4479 handle_pte_fault mm/memory.c:6318 [inline] __handle_mm_fault mm/memory.c:6456 [inline] handle_mm_fault+0x1bec/0x3310 mm/memory.c:6625 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x165b/0x29d0 mm/gup.c:1428 populate_vma_page_range+0x2be/0x3c0 mm/gup.c:1860 __mm_populate+0x25f/0x390 mm/gup.c:1963 mm_populate include/linux/mm.h:3899 [inline] vm_mmap_pgoff+0x3aa/0x4f0 mm/util.c:586 ksys_mmap_pgoff+0x51e/0x760 mm/mmap.c:605 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f882299aeb9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f88237a5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f8822c15fa0 RCX: 00007f882299aeb9 RDX: 00000000027ffff7 RSI: 0000000000600000 RDI: 0000200000000000 RBP: 00007f8822a08c1f R08: 0000000000000007 R09: 0000000000000000 R10: 0000000004012011 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8822c16038 R14: 00007f8822c15fa0 R15: 00007ffe8a5b09d8 Allocated by task 18790: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4456 [inline] slab_alloc_node mm/slub.c:4785 [inline] kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4792 vm_area_alloc+0x24/0x140 mm/vma_init.c:32 __mmap_new_vma mm/vma.c:2517 [inline] __mmap_region mm/vma.c:2759 [inline] mmap_region+0x10eb/0x2240 mm/vma.c:2837 do_mmap+0xc39/0x10c0 mm/mmap.c:559 vm_mmap_pgoff+0x2c9/0x4f0 mm/util.c:581 ksys_mmap_pgoff+0x51e/0x760 mm/mmap.c:605 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 8211: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2667 [inline] slab_free_after_rcu_debug+0x126/0x220 mm/slub.c:6144 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869 handle_softirqs+0x22a/0x870 kernel/softirq.c:626 __do_softirq kernel/softirq.c:660 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:727 irq_exit_rcu+0x9/0x30 kernel/softirq.c:743 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 slab_free_hook mm/slub.c:2628 [inline] slab_free mm/slub.c:6079 [inline] kmem_cache_free+0x426/0x630 mm/slub.c:6209 remove_vma mm/vma.c:470 [inline] vms_complete_munmap_vmas+0x929/0xc60 mm/vma.c:1342 __mmap_complete+0x7b/0x5e0 mm/vma.c:2588 __mmap_region mm/vma.c:2768 [inline] mmap_region+0x15a2/0x2240 mm/vma.c:2837 do_mmap+0xc39/0x10c0 mm/mmap.c:559 vm_mmap_pgoff+0x2c9/0x4f0 mm/util.c:581 ksys_mmap_pgoff+0x51e/0x760 mm/mmap.c:605 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88804030c280 which belongs to the cache vm_area_struct of size 256 The buggy address is located 88 bytes inside of freed 256-byte region [ffff88804030c280, ffff88804030c380) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4030c memcg:ffff88804030cf01 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff888140410500 dead000000000100 dead000000000122 raw: 0000000000000000 00000008000c000c 00000000f5000000 ffff88804030cf01 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 8211, tgid 8211 (udevd), ts 809580322390, free_ts 809482725879 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1883 prep_new_page mm/page_alloc.c:1891 [inline] get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3956 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5244 alloc_slab_page mm/slub.c:3235 [inline] allocate_slab+0x7b/0x660 mm/slub.c:3408 new_slab mm/slub.c:3466 [inline] refill_objects+0x331/0x3c0 mm/slub.c:7088 refill_sheaf mm/slub.c:2784 [inline] __pcs_replace_empty_main+0x2b9/0x620 mm/slub.c:4533 alloc_from_pcs mm/slub.c:4636 [inline] slab_alloc_node mm/slub.c:4770 [inline] kmem_cache_alloc_noprof+0x37d/0x650 mm/slub.c:4792 vm_area_alloc+0x24/0x140 mm/vma_init.c:32 __mmap_new_vma mm/vma.c:2517 [inline] __mmap_region mm/vma.c:2759 [inline] mmap_region+0x10eb/0x2240 mm/vma.c:2837 do_mmap+0xc39/0x10c0 mm/mmap.c:559 vm_mmap_pgoff+0x2c9/0x4f0 mm/util.c:581 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 23 tgid 23 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1432 [inline] __free_frozen_pages+0xc01/0xd80 mm/page_alloc.c:2972 __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:290 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869 handle_softirqs+0x22a/0x870 kernel/softirq.c:626 run_ksoftirqd+0x36/0x60 kernel/softirq.c:1067 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff88804030c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804030c200: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff88804030c280: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88804030c300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804030c380: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ==================================================================