================================================================== BUG: KASAN: slab-use-after-free in ocfs2_fault+0xd3/0x3f0 fs/ocfs2/mmap.c:41 Read of size 8 at addr ffff8880115cde18 by task syz.0.0/5357 CPU: 0 UID: 0 PID: 5357 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 ocfs2_fault+0xd3/0x3f0 fs/ocfs2/mmap.c:41 __do_fault+0x138/0x390 mm/memory.c:5152 do_read_fault mm/memory.c:5573 [inline] do_fault mm/memory.c:5707 [inline] do_pte_missing mm/memory.c:4234 [inline] handle_pte_fault mm/memory.c:6052 [inline] __handle_mm_fault+0x3611/0x5440 mm/memory.c:6195 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6364 faultin_page mm/gup.c:1144 [inline] __get_user_pages+0x1699/0x2ce0 mm/gup.c:1446 populate_vma_page_range+0x29f/0x3a0 mm/gup.c:1880 __mm_populate+0x24c/0x380 mm/gup.c:1983 mm_populate include/linux/mm.h:3367 [inline] vm_mmap_pgoff+0x387/0x4d0 mm/util.c:585 ksys_mmap_pgoff+0x51f/0x760 mm/mmap.c:604 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc55df8ebe9 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc55edf0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fc55e1c6090 RCX: 00007fc55df8ebe9 RDX: 00000000027ffff7 RSI: 0000000000600000 RDI: 0000200000000000 RBP: 00007fc55e011e19 R08: 0000000000000004 R09: 0000000000004000 R10: 0000000004012011 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc55e1c6128 R14: 00007fc55e1c6090 R15: 00007fffdcb23e58 Allocated by task 5357: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:330 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:356 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236 vm_area_alloc+0x24/0x140 mm/vma_init.c:31 __mmap_new_vma mm/vma.c:2461 [inline] __mmap_region mm/vma.c:2669 [inline] mmap_region+0xdc7/0x20c0 mm/vma.c:2739 do_mmap+0xc45/0x10d0 mm/mmap.c:558 vm_mmap_pgoff+0x2a6/0x4d0 mm/util.c:580 ksys_mmap_pgoff+0x51f/0x760 mm/mmap.c:604 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 15: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free_after_rcu_debug+0x129/0x2a0 mm/slub.c:4730 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xcab/0x1770 kernel/rcu/tree.c:2861 handle_softirqs+0x283/0x870 kernel/softirq.c:579 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968 smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:160 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548 slab_free_hook mm/slub.c:2378 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x2f6/0x400 mm/slub.c:4782 remove_vma mm/vma.c:468 [inline] vms_complete_munmap_vmas+0x626/0x8a0 mm/vma.c:1293 __mmap_complete mm/vma.c:2532 [inline] __mmap_region mm/vma.c:2677 [inline] mmap_region+0x11db/0x20c0 mm/vma.c:2739 do_mmap+0xc45/0x10d0 mm/mmap.c:558 vm_mmap_pgoff+0x2a6/0x4d0 mm/util.c:580 ksys_mmap_pgoff+0x51f/0x760 mm/mmap.c:604 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880115cddc0 which belongs to the cache vm_area_struct of size 256 The buggy address is located 88 bytes inside of freed 256-byte region [ffff8880115cddc0, ffff8880115cdec0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x115cd memcg:ffff888011babf01 anon flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff888030413b40 ffffea0000454180 dead000000000005 raw: 0000000000000000 00000000000c000c 00000000f5000000 ffff888011babf01 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5041, tgid 5041 (wait_iface), ts 46122986557, free_ts 46119005933 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2655 new_slab mm/slub.c:2709 [inline] ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891 __slab_alloc mm/slub.c:3981 [inline] __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] kmem_cache_alloc_noprof+0x283/0x3c0 mm/slub.c:4236 vm_area_dup+0x2b/0x680 mm/vma_init.c:122 __split_vma+0x1a9/0xa00 mm/vma.c:515 vms_gather_munmap_vmas+0x4ce/0x12f0 mm/vma.c:1380 __mmap_prepare mm/vma.c:2359 [inline] __mmap_region mm/vma.c:2651 [inline] mmap_region+0x724/0x20c0 mm/vma.c:2739 do_mmap+0xc45/0x10d0 mm/mmap.c:558 vm_mmap_pgoff+0x2a6/0x4d0 mm/util.c:580 ksys_mmap_pgoff+0x51f/0x760 mm/mmap.c:604 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5041 tgid 5041 stack trace: create_dummy_stack mm/page_owner.c:94 [inline] register_dummy_stack+0x89/0xe0 mm/page_owner.c:100 init_page_owner+0x2e/0x620 mm/page_owner.c:118 invoke_init_callbacks mm/page_ext.c:148 [inline] page_ext_init+0x511/0x550 mm/page_ext.c:486 mm_core_init+0x56/0x70 mm/mm_init.c:2789 Memory state around the buggy address: ffff8880115cdd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880115cdd80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb >ffff8880115cde00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880115cde80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880115cdf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================