EXT4-fs warning (device loop2): dx_probe:833: inode #2: comm syz.2.19: Unrecognised inode hash code 20 EXT4-fs warning (device loop2): dx_probe:966: inode #2: comm syz.2.19: Corrupt directory, running e2fsck is recommended ================================================================== BUG: KASAN: use-after-free in __ext4_check_dir_entry+0x7c2/0x970 fs/ext4/dir.c:85 Read of size 2 at addr ffff88811aa30003 by task syz.2.19/493 CPU: 1 PID: 493 Comm: syz.2.19 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:88 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106 print_address_description+0x71/0x200 mm/kasan/report.c:316 print_report+0x4a/0x60 mm/kasan/report.c:420 kasan_report+0x122/0x150 mm/kasan/report.c:524 __asan_report_load2_noabort+0x14/0x20 mm/kasan/report_generic.c:349 __ext4_check_dir_entry+0x7c2/0x970 fs/ext4/dir.c:85 ext4_readdir+0x1315/0x3e10 fs/ext4/dir.c:261 iterate_dir+0x271/0x610 fs/readdir.c:-1 __do_sys_getdents64 fs/readdir.c:369 [inline] __se_sys_getdents64+0xf2/0x250 fs/readdir.c:354 __x64_sys_getdents64+0x7b/0x90 fs/readdir.c:354 x64_sys_call+0x15c/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:218 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7feddd79bf79 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fedde657028 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007feddda15fa0 RCX: 00007feddd79bf79 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007feddd8327e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007feddda16038 R14: 00007feddda15fa0 R15: 00007ffdaf3c4fc8 Allocated by task 405: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505 __kasan_slab_alloc+0x72/0x80 mm/kasan/common.c:334 kasan_slab_alloc include/linux/kasan.h:202 [inline] slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768 slab_alloc_node mm/slub.c:3382 [inline] slab_alloc mm/slub.c:3392 [inline] __kmem_cache_alloc_lru mm/slub.c:3399 [inline] kmem_cache_alloc+0x16e/0x330 mm/slub.c:3408 vma_lock_alloc kernel/fork.c:470 [inline] vm_area_dup+0x65/0x280 kernel/fork.c:523 __split_vma+0x1d9/0x980 mm/mmap.c:2440 do_mas_align_munmap+0x781/0x1320 mm/mmap.c:2588 do_mas_munmap+0x241/0x2b0 mm/mmap.c:2751 __vm_munmap+0x1bd/0x330 mm/mmap.c:3050 __do_sys_munmap mm/mmap.c:3076 [inline] __se_sys_munmap mm/mmap.c:3072 [inline] __x64_sys_munmap+0x6b/0x80 mm/mmap.c:3072 x64_sys_call+0x8a/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:12 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 13: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x31/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:242 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:250 kasan_slab_free include/linux/kasan.h:178 [inline] slab_free_hook mm/slub.c:1750 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1776 slab_free mm/slub.c:3712 [inline] kmem_cache_free+0x12d/0x300 mm/slub.c:3737 vma_lock_free kernel/fork.c:482 [inline] __vm_area_free+0x6f/0x130 kernel/fork.c:536 vm_area_free_rcu_cb+0x15/0x20 kernel/fork.c:548 rcu_do_batch+0x52a/0xbc0 kernel/rcu/tree.c:2297 rcu_core+0x5c3/0xe80 kernel/rcu/tree.c:2557 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2574 handle_softirqs+0x1d7/0x600 kernel/softirq.c:642 run_ksoftirqd+0x28/0x30 kernel/softirq.c:1019 smpboot_thread_fn+0x4a0/0x910 kernel/smpboot.c:164 kthread+0x281/0x320 kernel/kthread.c:386 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff88811aa30000 which belongs to the cache vma_lock of size 64 The buggy address is located 3 bytes inside of 64-byte region [ffff88811aa30000, ffff88811aa30040) The buggy address belongs to the physical page: page:ffffea00046a8c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11aa30 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 0000000000000000 dead000000000001 ffff8881001ea900 raw: 0000000000000000 00000000002a002a 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 120, tgid 120 (dmi_memory_id), ts 5563614621, free_ts 5555311464 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2670 prep_new_page+0x1c/0x110 mm/page_alloc.c:2677 get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4583 __alloc_pages+0x1d9/0x480 mm/page_alloc.c:5897 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3d0 mm/slub.c:2020 ___slab_alloc+0x6bd/0xb20 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] slab_alloc mm/slub.c:3392 [inline] __kmem_cache_alloc_lru mm/slub.c:3399 [inline] kmem_cache_alloc+0x1b0/0x330 mm/slub.c:3408 vma_lock_alloc kernel/fork.c:470 [inline] vm_area_alloc+0xe9/0x1a0 kernel/fork.c:501 __mmap_region mm/mmap.c:2862 [inline] mmap_region+0xfff/0x21e0 mm/mmap.c:3030 do_mmap+0x856/0xdd0 mm/mmap.c:1491 vm_mmap_pgoff+0x224/0x410 mm/util.c:525 vm_mmap+0x87/0xb0 mm/util.c:545 elf_map+0x1aa/0x300 fs/binfmt_elf.c:375 load_elf_interp+0x4aa/0xd00 fs/binfmt_elf.c:664 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1578 [inline] free_pcp_prepare mm/page_alloc.c:1652 [inline] free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3618 free_unref_page_list+0x117/0x8c0 mm/page_alloc.c:3769 release_pages+0xaf2/0xb50 mm/swap.c:1048 free_pages_and_swap_cache+0x86/0xa0 mm/swap_state.c:315 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline] tlb_flush_mmu_free mm/mmu_gather.c:254 [inline] tlb_flush_mmu mm/mmu_gather.c:261 [inline] tlb_finish_mmu+0x1aa/0x370 mm/mmu_gather.c:361 exit_mmap+0x412/0xc10 mm/mmap.c:3384 __mmput+0x93/0x360 kernel/fork.c:1309 mmput+0x4b/0x150 kernel/fork.c:1333 exec_mmap+0x3de/0x460 fs/exec.c:1045 begin_new_exec+0x11ef/0x1da0 fs/exec.c:1317 load_elf_binary+0x97c/0x2800 fs/binfmt_elf.c:1028 search_binary_handler fs/exec.c:1767 [inline] exec_binprm fs/exec.c:1808 [inline] bprm_execve+0x79b/0x1450 fs/exec.c:1877 do_execveat_common+0x915/0xa70 fs/exec.c:1982 do_execve fs/exec.c:2056 [inline] __do_sys_execve fs/exec.c:2132 [inline] __se_sys_execve fs/exec.c:2127 [inline] __x64_sys_execve+0x92/0xb0 fs/exec.c:2127 x64_sys_call+0x98/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:60 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 Memory state around the buggy address: ffff88811aa2ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88811aa2ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88811aa30000: fa fb fb fb fb fb fb fb fc fc fc fc fa fb fb fb ^ ffff88811aa30080: fb fb fb fb fc fc fc fc fa fb fb fb fb fb fb fb ffff88811aa30100: fc fc fc fc fa fb fb fb fb fb fb fb fc fc fc fc ================================================================== EXT4-fs error (device loop2): ext4_readdir:263: inode #2: block 3: comm syz.2.19: path /2/file0: bad entry in directory: directory entry overrun - offset=2047, inode=3705667584, rec_len=33068, size=2048 fake=0 EXT4-fs error (device loop2) in ext4_reserve_inode_write:5935: Corrupt filesystem EXT4-fs error (device loop2): ext4_dirty_inode:6139: inode #2: comm syz.2.19: mark_inode_dirty error