loop0: rw=0, sector=6491536, nr_sectors = 2 limit=128 Buffer I/O error on dev loop0, logical block 3245768, async page read ================================================================== BUG: KASAN: use-after-free in sysv_new_inode+0xfc7/0x1160 fs/sysv/ialloc.c:153 Read of size 2 at addr ffff88804dca91ce by task syz-executor156/5123 CPU: 0 UID: 0 PID: 5123 Comm: syz-executor156 Not tainted 6.12.0-rc3-syzkaller-00389-g3d5ad2d4eca3 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __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 sysv_new_inode+0xfc7/0x1160 fs/sysv/ialloc.c:153 sysv_symlink+0x9f/0x180 fs/sysv/namei.c:80 vfs_symlink+0x137/0x2e0 fs/namei.c:4615 do_symlinkat+0x222/0x3a0 fs/namei.c:4641 __do_sys_symlink fs/namei.c:4662 [inline] __se_sys_symlink fs/namei.c:4660 [inline] __x64_sys_symlink+0x7a/0x90 fs/namei.c:4660 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: 0033:0x7f261bb60d09 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 1f 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:00007fffa472b018 EFLAGS: 00000246 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f261bb60d09 RDX: 0000000000000000 RSI: 00000000200059c0 RDI: 00000000200049c0 RBP: 00007fffa472b048 R08: 0000000000009e7f R09: 00007fffa472b0a0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fffa472b0a0 R13: 00007fffa472b060 R14: 000000000001026d R15: 0000000000000001 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x7f2612e00 pfn:0x4dca9 flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff) raw: 04fff00000000000 ffffea0001372e48 ffffea0001372a88 0000000000000000 raw: 00000007f2612e00 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Movable, gfp_mask 0x140dca(GFP_HIGHUSER_MOVABLE|__GFP_COMP|__GFP_ZERO), pid 5123, tgid 5123 (syz-executor156), ts 66463798108, free_ts 66465998448 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537 prep_new_page mm/page_alloc.c:1545 [inline] get_page_from_freelist+0x3045/0x3190 mm/page_alloc.c:3457 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4733 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265 folio_alloc_mpol_noprof mm/mempolicy.c:2283 [inline] vma_alloc_folio_noprof+0x12e/0x230 mm/mempolicy.c:2314 folio_prealloc+0x31/0x170 alloc_anon_folio mm/memory.c:4716 [inline] do_anonymous_page mm/memory.c:4773 [inline] do_pte_missing mm/memory.c:3963 [inline] handle_pte_fault+0x24dd/0x6800 mm/memory.c:5755 __handle_mm_fault mm/memory.c:5898 [inline] handle_mm_fault+0x1106/0x1bb0 mm/memory.c:6066 do_user_addr_fault arch/x86/mm/fault.c:1338 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x459/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 page last free pid 5123 tgid 5123 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1108 [inline] free_unref_folios+0xf12/0x18d0 mm/page_alloc.c:2686 folios_put_refs+0x76c/0x860 mm/swap.c:1007 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 vms_clear_ptes+0x437/0x530 mm/vma.c:1096 vms_complete_munmap_vmas+0x208/0x910 mm/vma.c:1140 do_vmi_align_munmap+0x613/0x730 mm/vma.c:1349 do_vmi_munmap+0x24e/0x2d0 mm/vma.c:1397 __vm_munmap+0x24c/0x480 mm/mmap.c:1610 __do_sys_munmap mm/mmap.c:1627 [inline] __se_sys_munmap mm/mmap.c:1624 [inline] __x64_sys_munmap+0x68/0x80 mm/mmap.c:1624 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: ffff88804dca9080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88804dca9100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88804dca9180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88804dca9200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88804dca9280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================