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BUG: KASAN: use-after-free in mas_safe_min lib/maple_tree.c:721 [inline]
BUG: KASAN: use-after-free in mas_next_nentry+0x9e4/0xab0 lib/maple_tree.c:4662
Read of size 8 at addr ffff888078cde820 by task syz-executor.2/9487

CPU: 0 PID: 9487 Comm: syz-executor.2 Not tainted 6.0.0-rc6-next-20220923-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15e/0x45d mm/kasan/report.c:395
 kasan_report+0xbb/0x1f0 mm/kasan/report.c:495
 mas_safe_min lib/maple_tree.c:721 [inline]
 mas_next_nentry+0x9e4/0xab0 lib/maple_tree.c:4662
 mas_next_entry lib/maple_tree.c:4757 [inline]
 mas_next+0x1fb/0xc90 lib/maple_tree.c:5868
 userfaultfd_unregister fs/userfaultfd.c:1657 [inline]
 userfaultfd_ioctl+0x33c3/0x4200 fs/userfaultfd.c:2005
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f017548a669
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0176557168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f01755abf80 RCX: 00007f017548a669
RDX: 0000000020000080 RSI: 000000008010aa01 RDI: 0000000000000004
RBP: 00007f01754e5560 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc01bedcdf R14: 00007f0176557300 R15: 0000000000022000
 </TASK>

Allocated by task 9487:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45
 kasan_set_track+0x21/0x30 mm/kasan/common.c:52
 __kasan_slab_alloc+0x7e/0x80 mm/kasan/common.c:325
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slab.h:754 [inline]
 kmem_cache_alloc_bulk+0x3f8/0x860 mm/slub.c:3792
 mt_alloc_bulk lib/maple_tree.c:157 [inline]
 mas_alloc_nodes+0x309/0x810 lib/maple_tree.c:1256
 mas_node_count_gfp lib/maple_tree.c:1316 [inline]
 mas_preallocate+0x1b7/0x360 lib/maple_tree.c:5719
 __vma_adjust+0x181/0x1a70 mm/mmap.c:715
 vma_adjust include/linux/mm.h:2664 [inline]
 __split_vma+0x4b0/0x5c0 mm/mmap.c:2236
 do_mas_align_munmap+0x54c/0xee0 mm/mmap.c:2361
 do_mas_munmap+0x26a/0x2b0 mm/mmap.c:2501
 mmap_region+0x219/0x1bf0 mm/mmap.c:2549
 do_mmap+0x825/0xf50 mm/mmap.c:1411
 vm_mmap_pgoff+0x1ab/0x270 mm/util.c:520
 ksys_mmap_pgoff+0x41b/0x5a0 mm/mmap.c:1457
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 9487:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45
 kasan_set_track+0x21/0x30 mm/kasan/common.c:52
 kasan_save_free_info+0x2a/0x40 mm/kasan/generic.c:511
 ____kasan_slab_free mm/kasan/common.c:236 [inline]
 ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1669 [inline]
 slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1695
 slab_free mm/slub.c:3599 [inline]
 kmem_cache_free_bulk.part.0+0x205/0x780 mm/slub.c:3717
 mt_free_bulk lib/maple_tree.c:163 [inline]
 mas_destroy+0x394/0x5c0 lib/maple_tree.c:5769
 mas_store_prealloc+0xec/0x150 lib/maple_tree.c:5704
 __vma_adjust+0x765/0x1a70 mm/mmap.c:810
 vma_adjust include/linux/mm.h:2664 [inline]
 __split_vma+0x295/0x5c0 mm/mmap.c:2239
 split_vma+0x9f/0xe0 mm/mmap.c:2272
 userfaultfd_unregister fs/userfaultfd.c:1641 [inline]
 userfaultfd_ioctl+0x3819/0x4200 fs/userfaultfd.c:2005
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff888078cde800
 which belongs to the cache maple_node of size 256
The buggy address is located 32 bytes inside of
 256-byte region [ffff888078cde800, ffff888078cde900)

The buggy address belongs to the physical page:
page:ffffea0001e33780 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffffea00009dda80 pfn:0x78cde
head:ffffea0001e33780 order:1 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffff88801184fdc0 dead000000100010 0000000000000000
raw: ffffea00009dda80 0000000000000003 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 9172, tgid 9172 (syz-executor.5), ts 370225230913, free_ts 348328039252
 prep_new_page mm/page_alloc.c:2538 [inline]
 get_page_from_freelist+0x1092/0x2d20 mm/page_alloc.c:4287
 __alloc_pages+0x1c7/0x5a0 mm/page_alloc.c:5546
 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2280
 alloc_slab_page mm/slub.c:1739 [inline]
 allocate_slab+0x213/0x300 mm/slub.c:1884
 new_slab mm/slub.c:1937 [inline]
 ___slab_alloc+0xac1/0x1430 mm/slub.c:3119
 kmem_cache_alloc_bulk+0x291/0x860 mm/slub.c:3768
 mt_alloc_bulk lib/maple_tree.c:157 [inline]
 mas_alloc_nodes+0x309/0x810 lib/maple_tree.c:1256
 mas_node_count_gfp lib/maple_tree.c:1316 [inline]
 mas_preallocate+0x1b7/0x360 lib/maple_tree.c:5719
 vma_expand+0x1cc/0xb60 mm/mmap.c:542
 mmap_region+0x1376/0x1bf0 mm/mmap.c:2591
 do_mmap+0x825/0xf50 mm/mmap.c:1411
 vm_mmap_pgoff+0x1ab/0x270 mm/util.c:520
 ksys_mmap_pgoff+0x41b/0x5a0 mm/mmap.c:1457
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1458 [inline]
 free_pcp_prepare+0x65c/0xd90 mm/page_alloc.c:1508
 free_unref_page_prepare mm/page_alloc.c:3386 [inline]
 free_unref_page+0x19/0x4d0 mm/page_alloc.c:3482
 kasan_depopulate_vmalloc_pte+0x5c/0x70 mm/kasan/shadow.c:372
 apply_to_pte_range mm/memory.c:2642 [inline]
 apply_to_pmd_range mm/memory.c:2686 [inline]
 apply_to_pud_range mm/memory.c:2722 [inline]
 apply_to_p4d_range mm/memory.c:2758 [inline]
 __apply_to_page_range+0x68c/0x1030 mm/memory.c:2792
 kasan_release_vmalloc+0xa7/0xc0 mm/kasan/shadow.c:486
 __purge_vmap_area_lazy+0x885/0x1c50 mm/vmalloc.c:1770
 drain_vmap_area_work+0x52/0xe0 mm/vmalloc.c:1799
 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289
 worker_thread+0x665/0x1080 kernel/workqueue.c:2436
 kthread+0x2e4/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306

Memory state around the buggy address:
 ffff888078cde700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888078cde780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888078cde800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff888078cde880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888078cde900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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