On 7/16/24 10:29 AM, syzbot wrote: > Hello, dunno about the [crypto?] parts, sounds rather something for Suren or Liam or maybe it's due to some changes to gup? > syzbot found the following issue on: > > HEAD commit: 3fe121b62282 Add linux-next specific files for 20240712 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=1097ebed980000 > kernel config: https://syzkaller.appspot.com/x/.config?x=98dd8c4bab5cdce > dashboard link: https://syzkaller.appspot.com/bug?extid=4c882a4a0697c4a25364 > 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=11d611a5980000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13ce3259980000 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/8c6fbf69718d/disk-3fe121b6.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/39fc7e43dfc1/vmlinux-3fe121b6.xz > kernel image: https://storage.googleapis.com/syzbot-assets/0a78e70e4b4e/bzImage-3fe121b6.xz > mounted in repro: https://storage.googleapis.com/syzbot-assets/66cfe5a679f2/mount_0.gz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+4c882a4a0697c4a25364@xxxxxxxxxxxxxxxxxxxxxxxxx > > ================================================================== > BUG: KASAN: slab-use-after-free in handle_mm_fault+0x14f0/0x19a0 mm/memory.c:5842 > Read of size 8 at addr ffff88802c4719d0 by task syz-executor125/5235 > > CPU: 1 UID: 0 PID: 5235 Comm: syz-executor125 Not tainted 6.10.0-rc7-next-20240712-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 > Call Trace: > <TASK> > __dump_stack lib/dump_stack.c:94 [inline] > dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 > 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 > handle_mm_fault+0x14f0/0x19a0 mm/memory.c:5842 > faultin_page mm/gup.c:1194 [inline] > __get_user_pages+0x6ec/0x16a0 mm/gup.c:1493 > populate_vma_page_range+0x264/0x330 mm/gup.c:1932 > __mm_populate+0x27a/0x460 mm/gup.c:2035 > mm_populate include/linux/mm.h:3429 [inline] > vm_mmap_pgoff+0x2c3/0x3d0 mm/util.c:593 > 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: 0033:0x7f093ce17fe9 > Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 1d 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:00007f093cd9e158 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 > RAX: ffffffffffffffda RBX: 00007f093ce9f4b8 RCX: 00007f093ce17fe9 > RDX: 0000000000000002 RSI: 0000000000b36000 RDI: 0000000020000000 > RBP: 00007f093ce9f4b0 R08: 00000000ffffffff R09: 0000000000000000 > R10: 0000000000008031 R11: 0000000000000246 R12: 00007f093ce9f4bc > R13: 000000000000006e R14: 00007ffe8008cc30 R15: 00007ffe8008cd18 > </TASK> > > Allocated by task 5235: > kasan_save_stack mm/kasan/common.c:47 [inline] > kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 > unpoison_slab_object mm/kasan/common.c:312 [inline] > __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 > kasan_slab_alloc include/linux/kasan.h:201 [inline] > slab_post_alloc_hook mm/slub.c:3988 [inline] > slab_alloc_node mm/slub.c:4037 [inline] > kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4044 > vm_area_alloc+0x24/0x1d0 kernel/fork.c:472 > mmap_region+0xc3d/0x2090 mm/mmap.c:2944 > do_mmap+0x8f9/0x1010 mm/mmap.c:1468 > vm_mmap_pgoff+0x1dd/0x3d0 mm/util.c:588 > 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 > > Freed by task 5237: > kasan_save_stack mm/kasan/common.c:47 [inline] > kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 > kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 > poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 > __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 > kasan_slab_free include/linux/kasan.h:184 [inline] > slab_free_hook mm/slub.c:2252 [inline] > slab_free mm/slub.c:4473 [inline] > kmem_cache_free+0x145/0x350 mm/slub.c:4548 > rcu_do_batch kernel/rcu/tree.c:2569 [inline] > rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2843 > handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 > __do_softirq kernel/softirq.c:588 [inline] > invoke_softirq kernel/softirq.c:428 [inline] > __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 > irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 > instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] > sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 > asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 > > Last potentially related work creation: > kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47 > __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541 > __call_rcu_common kernel/rcu/tree.c:3106 [inline] > call_rcu+0x167/0xa70 kernel/rcu/tree.c:3210 > remove_vma mm/mmap.c:189 [inline] > remove_mt mm/mmap.c:2415 [inline] > do_vmi_align_munmap+0x155c/0x18c0 mm/mmap.c:2758 > do_vmi_munmap+0x261/0x2f0 mm/mmap.c:2830 > mmap_region+0x72f/0x2090 mm/mmap.c:2881 > do_mmap+0x8f9/0x1010 mm/mmap.c:1468 > vm_mmap_pgoff+0x1dd/0x3d0 mm/util.c:588 > ksys_mmap_pgoff+0x544/0x720 mm/mmap.c:1514 > 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 > > The buggy address belongs to the object at ffff88802c4719b0 > which belongs to the cache vm_area_struct of size 184 > The buggy address is located 32 bytes inside of > freed 184-byte region [ffff88802c4719b0, ffff88802c471a68) > > The buggy address belongs to the physical page: > page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2c471 > memcg:ffff888024312e01 > flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) > page_type: 0xfdffffff(slab) > raw: 00fff00000000000 ffff888015eefb40 ffffea000091a480 0000000000000008 > raw: 0000000000000000 0000000080100010 00000001fdffffff ffff888024312e01 > page dumped because: kasan: bad access detected > page_owner tracks the page as allocated > page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 4769, tgid 4769 (S41dhcpcd), ts 42147845478, free_ts 42112307396 > set_page_owner include/linux/page_owner.h:32 [inline] > post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1493 > prep_new_page mm/page_alloc.c:1501 [inline] > get_page_from_freelist+0x2ccb/0x2d80 mm/page_alloc.c:3474 > __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4732 > __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] > alloc_pages_node_noprof include/linux/gfp.h:296 [inline] > alloc_slab_page+0x5f/0x120 mm/slub.c:2321 > allocate_slab+0x5a/0x2f0 mm/slub.c:2484 > new_slab mm/slub.c:2537 [inline] > ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3723 > __slab_alloc+0x58/0xa0 mm/slub.c:3813 > __slab_alloc_node mm/slub.c:3866 [inline] > slab_alloc_node mm/slub.c:4025 [inline] > kmem_cache_alloc_noprof+0x1c1/0x2a0 mm/slub.c:4044 > vm_area_dup+0x27/0x290 kernel/fork.c:487 > dup_mmap kernel/fork.c:696 [inline] > dup_mm kernel/fork.c:1674 [inline] > copy_mm+0xc7b/0x1f30 kernel/fork.c:1723 > copy_process+0x186b/0x3d90 kernel/fork.c:2376 > kernel_clone+0x226/0x8f0 kernel/fork.c:2788 > __do_sys_clone kernel/fork.c:2931 [inline] > __se_sys_clone kernel/fork.c:2915 [inline] > __x64_sys_clone+0x258/0x2a0 kernel/fork.c:2915 > 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 4768 tgid 4768 stack trace: > reset_page_owner include/linux/page_owner.h:25 [inline] > free_pages_prepare mm/page_alloc.c:1094 [inline] > free_unref_folios+0x103a/0x1b00 mm/page_alloc.c:2692 > folios_put_refs+0x76e/0x860 mm/swap.c:1039 > 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:3425 > __mmput+0x115/0x390 kernel/fork.c:1347 > exit_mm+0x220/0x310 kernel/exit.c:571 > do_exit+0x9b2/0x27f0 kernel/exit.c:869 > do_group_exit+0x207/0x2c0 kernel/exit.c:1031 > __do_sys_exit_group kernel/exit.c:1042 [inline] > __se_sys_exit_group kernel/exit.c:1040 [inline] > __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1040 > x64_sys_call+0x26c3/0x26d0 arch/x86/include/generated/asm/syscalls_64.h:232 > 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 > > Memory state around the buggy address: > ffff88802c471880: fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 00 > ffff88802c471900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc >>ffff88802c471980: fc fc fc fc fc fc fa fb fb fb fb fb fb fb fb fb > ^ > ffff88802c471a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc > ffff88802c471a80: fc fc fc fc fc 00 00 00 00 00 00 00 00 00 00 00 > ================================================================== > > > --- > 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. > > 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 >