Hello, syzbot found the following issue on: HEAD commit: 47ac09b91bef Linux 6.11-rc4 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=153eeafd980000 kernel config: https://syzkaller.appspot.com/x/.config?x=df2f0ed7e30a639d dashboard link: https://syzkaller.appspot.com/bug?extid=0c2508114d912a54ee79 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=1335fe05980000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=156ba6fd980000 Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-47ac09b9.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/6db2a1c6b666/vmlinux-47ac09b9.xz kernel image: https://storage.googleapis.com/syzbot-assets/b1c782255526/bzImage-47ac09b9.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/83fcfca5f30f/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+0c2508114d912a54ee79@xxxxxxxxxxxxxxxxxxxxxxxxx EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. loop0: detected capacity change from 2048 to 2047 ================================================================== BUG: KASAN: use-after-free in ext4_search_dir+0xf2/0x1c0 fs/ext4/namei.c:1500 Read of size 1 at addr ffff88803e91130f by task syz-executor269/5103 CPU: 0 UID: 0 PID: 5103 Comm: syz-executor269 Not tainted 6.11.0-rc4-syzkaller #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: <TASK> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 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 ext4_search_dir+0xf2/0x1c0 fs/ext4/namei.c:1500 ext4_find_inline_entry+0x4be/0x5e0 fs/ext4/inline.c:1697 __ext4_find_entry+0x2b4/0x1b30 fs/ext4/namei.c:1573 ext4_lookup_entry fs/ext4/namei.c:1727 [inline] ext4_lookup+0x15f/0x750 fs/ext4/namei.c:1795 lookup_one_qstr_excl+0x11f/0x260 fs/namei.c:1633 filename_create+0x297/0x540 fs/namei.c:3980 do_symlinkat+0xf9/0x3a0 fs/namei.c:4587 __do_sys_symlinkat fs/namei.c:4610 [inline] __se_sys_symlinkat fs/namei.c:4607 [inline] __x64_sys_symlinkat+0x95/0xb0 fs/namei.c:4607 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: 0033:0x7f3e73ced469 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 21 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff4d40c258 EFLAGS: 00000246 ORIG_RAX: 000000000000010a RAX: ffffffffffffffda RBX: 0032656c69662f2e RCX: 00007f3e73ced469 RDX: 0000000020000200 RSI: 00000000ffffff9c RDI: 00000000200001c0 RBP: 0000000000000000 R08: 00007fff4d40c290 R09: 00007fff4d40c290 R10: 0023706f6f6c2f76 R11: 0000000000000246 R12: 00007fff4d40c27c R13: 0000000000000003 R14: 431bde82d7b634db R15: 00007fff4d40c2b0 </TASK> The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x7fb7091d9 pfn:0x3e911 flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff) raw: 04fff00000000000 dead000000000100 dead000000000122 0000000000000000 raw: 00000007fb7091d9 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 5083, tgid 5083 (sshd), ts 84338308196, free_ts 84419190442 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+0x2e4c/0x2f10 mm/page_alloc.c:3439 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4695 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2263 folio_alloc_mpol_noprof mm/mempolicy.c:2281 [inline] vma_alloc_folio_noprof+0x12e/0x230 mm/mempolicy.c:2312 folio_prealloc+0x31/0x170 alloc_anon_folio mm/memory.c:4498 [inline] do_anonymous_page mm/memory.c:4555 [inline] do_pte_missing mm/memory.c:3945 [inline] handle_pte_fault+0x255e/0x6fc0 mm/memory.c:5521 __handle_mm_fault mm/memory.c:5664 [inline] handle_mm_fault+0x1029/0x1980 mm/memory.c:5832 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 5083 tgid 5083 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:2660 folios_put_refs+0x76e/0x860 mm/swap.c:1039 free_pages_and_swap_cache+0x2ea/0x690 mm/swap_state.c:332 __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 unmap_region+0x2df/0x350 mm/mmap.c:2441 do_vmi_align_munmap+0x1122/0x18c0 mm/mmap.c:2754 do_vmi_munmap+0x261/0x2f0 mm/mmap.c:2830 __vm_munmap+0x1fc/0x400 mm/mmap.c:3109 __do_sys_munmap mm/mmap.c:3126 [inline] __se_sys_munmap mm/mmap.c:3123 [inline] __x64_sys_munmap+0x68/0x80 mm/mmap.c:3123 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: ffff88803e911200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88803e911280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88803e911300: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88803e911380: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88803e911400: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== --- This report is generated by a bot. 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