Hello, syzbot found the following issue on: HEAD commit: d35b2284e966 Add linux-next specific files for 20240607 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=178b77ba980000 kernel config: https://syzkaller.appspot.com/x/.config?x=d8bf5cd6bcca7343 dashboard link: https://syzkaller.appspot.com/bug?extid=d6e5c328862b5ae6cbfe compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=174c680a980000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=111b9696980000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/e0055a00a2cb/disk-d35b2284.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/192cbb8cf833/vmlinux-d35b2284.xz kernel image: https://storage.googleapis.com/syzbot-assets/57804c9c9319/bzImage-d35b2284.xz The issue was bisected to: commit 1c05047ad01693ad92bdf8347fad3b5c2b25e8bb Author: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> Date: Tue Jun 4 10:17:45 2024 +0000 mm: memory: extend finish_fault() to support large folio bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=11267f94980000 final oops: https://syzkaller.appspot.com/x/report.txt?x=13267f94980000 console output: https://syzkaller.appspot.com/x/log.txt?x=15267f94980000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+d6e5c328862b5ae6cbfe@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 1c05047ad016 ("mm: memory: extend finish_fault() to support large folio") ================================================================== BUG: KASAN: use-after-free in ptep_get include/linux/pgtable.h:317 [inline] BUG: KASAN: use-after-free in ptep_get_lockless include/linux/pgtable.h:581 [inline] BUG: KASAN: use-after-free in pte_range_none mm/memory.c:4409 [inline] BUG: KASAN: use-after-free in finish_fault+0xf87/0x1460 mm/memory.c:4905 Read of size 8 at addr ffff88807bfb7000 by task syz-executor149/5117 CPU: 0 PID: 5117 Comm: syz-executor149 Not tainted 6.10.0-rc2-next-20240607-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:91 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:117 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 ptep_get include/linux/pgtable.h:317 [inline] ptep_get_lockless include/linux/pgtable.h:581 [inline] pte_range_none mm/memory.c:4409 [inline] finish_fault+0xf87/0x1460 mm/memory.c:4905 do_read_fault mm/memory.c:5052 [inline] do_fault mm/memory.c:5178 [inline] do_pte_missing mm/memory.c:3948 [inline] handle_pte_fault+0x3db5/0x7130 mm/memory.c:5502 __handle_mm_fault mm/memory.c:5645 [inline] handle_mm_fault+0x10df/0x1ba0 mm/memory.c:5810 faultin_page mm/gup.c:1339 [inline] __get_user_pages+0x6ef/0x1590 mm/gup.c:1638 populate_vma_page_range+0x264/0x330 mm/gup.c:2078 __mm_populate+0x27a/0x460 mm/gup.c:2181 mm_populate include/linux/mm.h:3442 [inline] __do_sys_remap_file_pages mm/mmap.c:3177 [inline] __se_sys_remap_file_pages+0x7a1/0x9a0 mm/mmap.c:3103 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff1cbb3e399 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff1cbad8238 EFLAGS: 00000246 ORIG_RAX: 00000000000000d8 RAX: ffffffffffffffda RBX: 00007ff1cbbc8318 RCX: 00007ff1cbb3e399 RDX: 0000000000000000 RSI: 0000000000200000 RDI: 00000000202ec000 RBP: 00007ff1cbbc8310 R08: 0000000000000000 R09: 00007ff1cbad86c0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff1cbbc831c R13: 0000000000000000 R14: 00007ffcff8e0350 R15: 00007ffcff8e0438 </TASK> The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7bfb7 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea00007ed408 ffff8880b94448a0 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x440dc0(GFP_KERNEL_ACCOUNT|__GFP_COMP|__GFP_ZERO), pid 5097, tgid 5088 (syz-executor149), ts 55842453591, free_ts 55925905863 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1470 prep_new_page mm/page_alloc.c:1478 [inline] get_page_from_freelist+0x2cbd/0x2d70 mm/page_alloc.c:3457 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4715 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2263 pagetable_alloc_noprof include/linux/mm.h:2881 [inline] __pte_alloc_one_noprof include/asm-generic/pgalloc.h:70 [inline] pte_alloc_one+0x88/0x5d0 arch/x86/mm/pgtable.c:33 do_fault_around mm/memory.c:5000 [inline] do_read_fault mm/memory.c:5039 [inline] do_fault mm/memory.c:5178 [inline] do_pte_missing mm/memory.c:3948 [inline] handle_pte_fault+0x2ba7/0x7130 mm/memory.c:5502 __handle_mm_fault mm/memory.c:5645 [inline] handle_mm_fault+0x10df/0x1ba0 mm/memory.c:5810 faultin_page mm/gup.c:1339 [inline] __get_user_pages+0x6ef/0x1590 mm/gup.c:1638 populate_vma_page_range+0x264/0x330 mm/gup.c:2078 __mm_populate+0x27a/0x460 mm/gup.c:2181 mm_populate include/linux/mm.h:3442 [inline] __do_sys_remap_file_pages mm/mmap.c:3177 [inline] __se_sys_remap_file_pages+0x7a1/0x9a0 mm/mmap.c:3103 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5097 tgid 5088 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1089 [inline] free_unref_folios+0x103a/0x1b00 mm/page_alloc.c:2669 folios_put_refs+0x76e/0x860 mm/swap.c:1020 free_pages_and_swap_cache+0x5c8/0x690 mm/swap_state.c:335 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline] tlb_batch_pages_flush mm/mmu_gather.c:149 [inline] tlb_flush_mmu_free mm/mmu_gather.c:366 [inline] tlb_flush_mmu+0x3a3/0x680 mm/mmu_gather.c:373 tlb_finish_mmu+0xd4/0x200 mm/mmu_gather.c:465 exit_mmap+0x44f/0xc80 mm/mmap.c:3395 __mmput+0x115/0x390 kernel/fork.c:1341 exit_mm+0x220/0x310 kernel/exit.c:565 do_exit+0x9aa/0x28e0 kernel/exit.c:861 do_group_exit+0x207/0x2c0 kernel/exit.c:1023 get_signal+0x16a1/0x1740 kernel/signal.c:2909 arch_do_signal_or_restart+0x96/0x830 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88807bfb6f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88807bfb6f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88807bfb7000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88807bfb7080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88807bfb7100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. For information about bisection process see: https://goo.gl/tpsmEJ#bisection If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
