================================================================== BUG: KASAN: slab-use-after-free in ocfs2_fault+0xda/0x3e0 fs/ocfs2/mmap.c:41 Read of size 8 at addr ffff888043df7918 by task syz.0.0/5320 CPU: 0 UID: 0 PID: 5320 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 04/01/2014 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+0xda/0x3e0 fs/ocfs2/mmap.c:41 __do_fault+0x138/0x390 mm/memory.c:5355 do_shared_fault mm/memory.c:5854 [inline] do_fault mm/memory.c:5928 [inline] do_pte_missing+0x5c4/0x3750 mm/memory.c:4469 handle_pte_fault mm/memory.c:6308 [inline] __handle_mm_fault mm/memory.c:6446 [inline] handle_mm_fault+0x1bec/0x3310 mm/memory.c:6615 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x165b/0x29d0 mm/gup.c:1428 __get_user_pages_locked mm/gup.c:1692 [inline] __gup_longterm_locked+0x1221/0x1630 mm/gup.c:2476 gup_fast_fallback+0x1d82/0x22e0 mm/gup.c:3209 iov_iter_extract_user_pages lib/iov_iter.c:1763 [inline] iov_iter_extract_pages+0x37b/0x5f0 lib/iov_iter.c:1826 dio_refill_pages fs/direct-io.c:172 [inline] dio_get_page fs/direct-io.c:213 [inline] do_direct_IO fs/direct-io.c:915 [inline] __blockdev_direct_IO+0x1071/0x32f0 fs/direct-io.c:1243 ocfs2_direct_IO+0x251/0x2c0 fs/ocfs2/aops.c:2441 generic_file_read_iter+0x31c/0x510 mm/filemap.c:2969 ocfs2_file_read_iter+0x3fc/0xa80 fs/ocfs2/file.c:2596 aio_read+0x33a/0x4d0 fs/aio.c:1603 __io_submit_one fs/aio.c:-1 [inline] io_submit_one+0x79d/0x14c0 fs/aio.c:2053 __do_sys_io_submit fs/aio.c:2112 [inline] __se_sys_io_submit+0x195/0x340 fs/aio.c:2082 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: 0033:0x7f7c6df9bf79 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:00007f7c6ee39028 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1 RAX: ffffffffffffffda RBX: 00007f7c6e216090 RCX: 00007f7c6df9bf79 RDX: 0000200000001d00 RSI: 000000001ffffff0 RDI: 00007f7c6ee00000 RBP: 00007f7c6e0327e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7c6e216128 R14: 00007f7c6e216090 R15: 00007ffd2495e968 Allocated by task 5319: 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:4459 [inline] slab_alloc_node mm/slub.c:4788 [inline] kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4795 vm_area_alloc+0x24/0x140 mm/vma_init.c:32 __mmap_new_vma mm/vma.c:2510 [inline] __mmap_region mm/vma.c:2752 [inline] mmap_region+0xf90/0x1f50 mm/vma.c:2830 do_mmap+0xc39/0x10c0 mm/mmap.c:558 vm_mmap_pgoff+0x2c9/0x4f0 mm/util.c:581 ksys_mmap_pgoff+0x51e/0x760 mm/mmap.c:604 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 15: 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:2670 [inline] slab_free_after_rcu_debug+0x126/0x220 mm/slub.c:6147 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869 handle_softirqs+0x22a/0x7c0 kernel/softirq.c:622 run_ksoftirqd+0x36/0x60 kernel/softirq.c:1063 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 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:2631 [inline] slab_free mm/slub.c:6082 [inline] kmem_cache_free+0x434/0x610 mm/slub.c:6212 remove_vma mm/vma.c:467 [inline] vms_complete_munmap_vmas+0x625/0x890 mm/vma.c:1336 __mmap_complete+0x7b/0x5e0 mm/vma.c:2581 __mmap_region mm/vma.c:2761 [inline] mmap_region+0x1bdf/0x1f50 mm/vma.c:2830 do_mmap+0xc39/0x10c0 mm/mmap.c:558 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 The buggy address belongs to the object at ffff888043df78c0 which belongs to the cache vm_area_struct of size 256 The buggy address is located 88 bytes inside of freed 256-byte region [ffff888043df78c0, ffff888043df79c0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888043df7a00 pfn:0x43df7 memcg:ffff888043df7f01 flags: 0x4fff00000000200(workingset|node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000200 ffff88801be9eb40 ffffea000105f1d0 ffff888030408dc8 raw: ffff888043df7a00 00000008000c0008 00000000f5000000 ffff888043df7f01 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 5319, tgid 5318 (syz.0.0), ts 85128021343, free_ts 85127769653 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:3238 [inline] allocate_slab+0x77/0x660 mm/slub.c:3411 new_slab mm/slub.c:3469 [inline] refill_objects+0x331/0x3c0 mm/slub.c:7091 refill_sheaf mm/slub.c:2787 [inline] __pcs_replace_empty_main+0x2b9/0x620 mm/slub.c:4536 alloc_from_pcs mm/slub.c:4639 [inline] slab_alloc_node mm/slub.c:4773 [inline] kmem_cache_alloc_noprof+0x37d/0x650 mm/slub.c:4795 vm_area_alloc+0x24/0x140 mm/vma_init.c:32 __mmap_new_vma mm/vma.c:2510 [inline] __mmap_region mm/vma.c:2752 [inline] mmap_region+0xf90/0x1f50 mm/vma.c:2830 do_mmap+0xc39/0x10c0 mm/mmap.c:558 vm_mmap_pgoff+0x2c9/0x4f0 mm/util.c:581 ksys_mmap_pgoff+0x51e/0x760 mm/mmap.c:604 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 5319 tgid 5318 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_batch_list_free mm/mmu_gather.c:161 [inline] tlb_finish_mmu+0x144/0x230 mm/mmu_gather.c:533 vms_clear_ptes+0x44d/0x570 mm/vma.c:1278 vms_clean_up_area mm/vma.c:1290 [inline] __mmap_setup mm/vma.c:2442 [inline] __mmap_region mm/vma.c:2734 [inline] mmap_region+0xa8d/0x1f50 mm/vma.c:2830 do_mmap+0xc39/0x10c0 mm/mmap.c:558 vm_mmap_pgoff+0x2c9/0x4f0 mm/util.c:581 ksys_mmap_pgoff+0x51e/0x760 mm/mmap.c:604 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 Memory state around the buggy address: ffff888043df7800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888043df7880: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb >ffff888043df7900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888043df7980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888043df7a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================