================================================================== 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 ffff8880340aa220 by task syz-executor.2/11786 CPU: 1 PID: 11786 Comm: syz-executor.2 Not tainted 6.1.0-rc3-syzkaller-00158-gee6050c8af96 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __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+0x3538/0x4260 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: 0033:0x7fa67fe8b5a9 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:00007fa67f1ff168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fa67ffac050 RCX: 00007fa67fe8b5a9 RDX: 0000000020000240 RSI: 000000008010aa01 RDI: 0000000000000006 RBP: 00007fa67fee67b0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa6800cfb1f R14: 00007fa67f1ff300 R15: 0000000000022000 Allocated by task 11770: 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 11786: 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+0x395d/0x4260 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 ffff8880340aa200 which belongs to the cache maple_node of size 256 The buggy address is located 32 bytes inside of 256-byte region [ffff8880340aa200, ffff8880340aa300) The buggy address belongs to the physical page: page:ffffea0000d02a80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x340aa head:ffffea0000d02a80 order:1 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff88801184fdc0 raw: 0000000000000000 0000000080100010 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 11770, tgid 11770 (syz-executor.2), ts 2830126867887, free_ts 2829753054439 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x10b5/0x2d50 mm/page_alloc.c:4288 __alloc_pages+0x1c7/0x5a0 mm/page_alloc.c:5555 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:1459 [inline] free_pcp_prepare+0x65c/0xd90 mm/page_alloc.c:1509 free_unref_page_prepare mm/page_alloc.c:3387 [inline] free_unref_page+0x19/0x4d0 mm/page_alloc.c:3483 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_lru+0x254/0x730 mm/slub.c:3429 alloc_inode_sb include/linux/fs.h:3117 [inline] sock_alloc_inode+0x23/0x1d0 net/socket.c:304 alloc_inode+0x61/0x230 fs/inode.c:259 new_inode_pseudo+0x13/0x80 fs/inode.c:1018 sock_alloc+0x3c/0x260 net/socket.c:627 __sock_create+0xb9/0x790 net/socket.c:1479 sock_create net/socket.c:1566 [inline] __sys_socket_create net/socket.c:1603 [inline] __sys_socket_create net/socket.c:1588 [inline] __sys_socket+0x12f/0x240 net/socket.c:1636 __do_sys_socket net/socket.c:1649 [inline] __se_sys_socket net/socket.c:1647 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1647 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: ffff8880340aa100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880340aa180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880340aa200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880340aa280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880340aa300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================