================================================================== BUG: KASAN: use-after-free in mas_safe_min lib/maple_tree.c:721 [inline] BUG: KASAN: use-after-free in mas_next_nentry lib/maple_tree.c:4662 [inline] BUG: KASAN: use-after-free in mas_next_entry+0x344/0x10f0 lib/maple_tree.c:4757 Read of size 8 at addr ffff88801ea79220 by task syz-executor379/3613 CPU: 0 PID: 3613 Comm: syz-executor379 Not tainted 6.1.0-rc1-syzkaller-00249-g4da34b7d175d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description+0x74/0x340 mm/kasan/report.c:284 print_report+0x107/0x220 mm/kasan/report.c:395 kasan_report+0x139/0x170 mm/kasan/report.c:495 mas_safe_min lib/maple_tree.c:721 [inline] mas_next_nentry lib/maple_tree.c:4662 [inline] mas_next_entry+0x344/0x10f0 lib/maple_tree.c:4757 userfaultfd_unregister+0x1240/0x13b0 fs/userfaultfd.c:1657 userfaultfd_ioctl+0x5a1/0x3230 fs/userfaultfd.c:2005 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7efce94ac5f9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 a1 15 00 00 90 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:00007efce945a318 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007efce95354a8 RCX: 00007efce94ac5f9 RDX: 0000000020000000 RSI: 000000008010aa01 RDI: 0000000000000003 RBP: 00007efce95354a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007efce95354ac R13: 00007ffc7d044eef R14: 00007efce945a400 R15: 0000000000022000 Allocated by task 3602: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x65/0x70 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+0x43d/0x580 mm/slub.c:3854 mt_alloc_bulk lib/maple_tree.c:157 [inline] mas_alloc_nodes+0x386/0x650 lib/maple_tree.c:1256 mas_node_count_gfp lib/maple_tree.c:1316 [inline] mas_node_count lib/maple_tree.c:1330 [inline] mas_expected_entries+0x215/0x340 lib/maple_tree.c:5822 dup_mmap+0x5f6/0xff0 kernel/fork.c:613 dup_mm+0x8c/0x310 kernel/fork.c:1526 copy_mm+0xcb/0x160 kernel/fork.c:1575 copy_process+0x1973/0x3fc0 kernel/fork.c:2253 kernel_clone+0x227/0x640 kernel/fork.c:2671 __do_sys_clone kernel/fork.c:2812 [inline] __se_sys_clone kernel/fork.c:2796 [inline] __x64_sys_clone+0x276/0x2e0 kernel/fork.c:2796 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 3613: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:511 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook+0x12e/0x1a0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] kmem_cache_free_bulk+0x137/0x1a0 mm/slub.c:3779 mt_free_bulk lib/maple_tree.c:163 [inline] mas_destroy+0x2d02/0x37b0 lib/maple_tree.c:5769 mas_store_prealloc+0x35d/0x450 lib/maple_tree.c:5704 vma_mas_store mm/mmap.c:435 [inline] __vma_adjust+0x1a93/0x2120 mm/mmap.c:811 __split_vma+0x374/0x4f0 userfaultfd_unregister+0x119b/0x13b0 fs/userfaultfd.c:1641 userfaultfd_ioctl+0x5a1/0x3230 fs/userfaultfd.c:2005 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff88801ea79200 which belongs to the cache maple_node of size 256 The buggy address is located 32 bytes inside of 256-byte region [ffff88801ea79200, ffff88801ea79300) The buggy address belongs to the physical page: page:ffffea00007a9e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1ea78 head:ffffea00007a9e00 order:1 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff88801204fdc0 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3602, tgid 3602 (syz-executor379), ts 40896714662, free_ts 36283338200 prep_new_page mm/page_alloc.c:2538 [inline] get_page_from_freelist+0x72b/0x7a0 mm/page_alloc.c:4287 __alloc_pages+0x259/0x560 mm/page_alloc.c:5554 alloc_slab_page+0x70/0xf0 mm/slub.c:1794 allocate_slab+0x5e/0x4b0 mm/slub.c:1939 new_slab mm/slub.c:1992 [inline] ___slab_alloc+0x7f4/0xeb0 mm/slub.c:3180 kmem_cache_alloc_bulk+0x1f1/0x580 mm/slub.c:3830 mt_alloc_bulk lib/maple_tree.c:157 [inline] mas_alloc_nodes+0x386/0x650 lib/maple_tree.c:1256 mas_node_count_gfp lib/maple_tree.c:1316 [inline] mas_preallocate+0x133/0x340 lib/maple_tree.c:5719 mmap_region+0x1446/0x1db0 mm/mmap.c:2681 do_mmap+0x8d9/0xf60 mm/mmap.c:1412 vm_mmap_pgoff+0x1e5/0x2f0 mm/util.c:520 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 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+0x80c/0x8f0 mm/page_alloc.c:1508 free_unref_page_prepare mm/page_alloc.c:3386 [inline] free_unref_page+0x7d/0x630 mm/page_alloc.c:3482 free_slab mm/slub.c:2031 [inline] discard_slab mm/slub.c:2037 [inline] __unfreeze_partials+0x1ab/0x200 mm/slub.c:2586 put_cpu_partial+0x116/0x180 mm/slub.c:2662 qlist_free_all+0x2b/0x70 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x169/0x180 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1f/0x70 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] kmem_cache_alloc_node+0x1ca/0x340 mm/slub.c:3443 __alloc_skb+0xd5/0x620 net/core/skbuff.c:497 alloc_skb include/linux/skbuff.h:1267 [inline] alloc_skb_with_frags+0xb4/0x780 net/core/skbuff.c:6124 sock_alloc_send_pskb+0x930/0xa70 net/core/sock.c:2719 unix_dgram_sendmsg+0x5b3/0x2050 net/unix/af_unix.c:1943 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg net/socket.c:734 [inline] __sys_sendto+0x46d/0x5f0 net/socket.c:2117 __do_sys_sendto net/socket.c:2129 [inline] __se_sys_sendto net/socket.c:2125 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2125 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff88801ea79100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801ea79180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801ea79200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801ea79280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801ea79300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================