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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 ffff888012701228 by task syz-executor.0/10972

CPU: 0 PID: 10972 Comm: syz-executor.0 Not tainted 6.1.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
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: 0033:0x7f672d88b5f9
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:00007f672d1ff168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f672d9abf80 RCX: 00007f672d88b5f9
RDX: 00000000200000c0 RSI: 000000008010aa01 RDI: 0000000000000004
RBP: 00007f672d8e67b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f672dedfb1f R14: 00007f672d1ff300 R15: 0000000000022000
 </TASK>

Allocated by task 10971:
 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:737 [inline]
 kmem_cache_alloc_bulk+0x3e9/0x830 mm/slub.c:3854
 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+0x18e/0x1ae0 mm/mmap.c:716
 vma_adjust include/linux/mm.h:2663 [inline]
 __split_vma+0x4b0/0x5c0 mm/mmap.c:2237
 split_vma+0x9f/0xe0 mm/mmap.c:2273
 mprotect_fixup+0x6c7/0x960 mm/mprotect.c:617
 do_mprotect_pkey+0x6fd/0xa70 mm/mprotect.c:792
 __do_sys_mprotect mm/mprotect.c:819 [inline]
 __se_sys_mprotect mm/mprotect.c:816 [inline]
 __x64_sys_mprotect+0x74/0xb0 mm/mprotect.c:816
 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 10972:
 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:1724 [inline]
 slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1750
 slab_free mm/slub.c:3661 [inline]
 kmem_cache_free_bulk.part.0+0x205/0x780 mm/slub.c:3779
 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+0x772/0x1ae0 mm/mmap.c:811
 vma_adjust include/linux/mm.h:2663 [inline]
 __split_vma+0x295/0x5c0 mm/mmap.c:2240
 split_vma+0x9f/0xe0 mm/mmap.c:2273
 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 ffff888012701200
 which belongs to the cache maple_node of size 256
The buggy address is located 40 bytes inside of
 256-byte region [ffff888012701200, ffff888012701300)

The buggy address belongs to the physical page:
page:ffffea000049c000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12700
head:ffffea000049c000 order:1 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001f6c980 dead000000000003 ffff88801184fdc0
raw: 0000000000000000 0000000000100010 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 10751, tgid 10751 (syz-executor.1), ts 1463114187803, free_ts 1416278130674
 prep_new_page mm/page_alloc.c:2538 [inline]
 get_page_from_freelist+0x10b5/0x2d50 mm/page_alloc.c:4287
 __alloc_pages+0x1c7/0x5a0 mm/page_alloc.c:5554
 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2285
 alloc_slab_page mm/slub.c:1794 [inline]
 allocate_slab+0x213/0x300 mm/slub.c:1939
 new_slab mm/slub.c:1992 [inline]
 ___slab_alloc+0xa91/0x1400 mm/slub.c:3180
 kmem_cache_alloc_bulk+0x28b/0x830 mm/slub.c:3830
 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+0x18e/0x1ae0 mm/mmap.c:716
 vma_adjust include/linux/mm.h:2663 [inline]
 __split_vma+0x4b0/0x5c0 mm/mmap.c:2237
 split_vma+0x9f/0xe0 mm/mmap.c:2273
 mprotect_fixup+0x6c7/0x960 mm/mprotect.c:617
 do_mprotect_pkey+0x6fd/0xa70 mm/mprotect.c:792
 __do_sys_mprotect mm/mprotect.c:819 [inline]
 __se_sys_mprotect mm/mprotect.c:816 [inline]
 __x64_sys_mprotect+0x74/0xb0 mm/mprotect.c:816
 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
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x62/0x80 mm/kasan/common.c:302
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slab.h:737 [inline]
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x1af/0x3c0 mm/slub.c:3422
 kmem_cache_zalloc include/linux/slab.h:702 [inline]
 taskstats_tgid_alloc kernel/taskstats.c:583 [inline]
 taskstats_exit+0x5ef/0xb70 kernel/taskstats.c:622
 do_exit+0x8a7/0x2a20 kernel/exit.c:805
 do_group_exit+0xd0/0x2a0 kernel/exit.c:950
 __do_sys_exit_group kernel/exit.c:961 [inline]
 __se_sys_exit_group kernel/exit.c:959 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:959
 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

Memory state around the buggy address:
 ffff888012701100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888012701180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888012701200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff888012701280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888012701300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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