EXT4-fs warning (device loop1): dx_probe:892: inode #2: comm syz-executor.1: dx entry: limit 0 != root limit 124 EXT4-fs warning (device loop1): dx_probe:965: inode #2: comm syz-executor.1: Corrupt directory, running e2fsck is recommended ================================================================== BUG: KASAN: use-after-free in __ext4_check_dir_entry+0x6f3/0x870 fs/ext4/dir.c:85 Read of size 2 at addr ffff88805155e003 by task syz-executor.1/10687 CPU: 0 PID: 10687 Comm: syz-executor.1 Not tainted 6.1.92-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15f/0x4f0 mm/kasan/report.c:395 kasan_report+0x136/0x160 mm/kasan/report.c:495 __ext4_check_dir_entry+0x6f3/0x870 fs/ext4/dir.c:85 ext4_readdir+0x139e/0x3950 fs/ext4/dir.c:258 iterate_dir+0x224/0x560 __do_sys_getdents64 fs/readdir.c:369 [inline] __se_sys_getdents64+0x209/0x4f0 fs/readdir.c:354 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7efd9d67cf69 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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:00007efd9e3a40c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007efd9d7b3fa0 RCX: 00007efd9d67cf69 RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000008 RBP: 00007efd9d6da706 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007efd9d7b3fa0 R15: 00007ffd532efc58 The buggy address belongs to the physical page: page:ffffea0001455780 refcount:0 mapcount:-128 mapping:0000000000000000 index:0x1 pfn:0x5155e flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea0001535108 ffffea00015ae888 0000000000000000 raw: 0000000000000001 0000000000000001 00000000ffffff7f 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 10615, tgid 10610 (syz-executor.1), ts 395471193868, free_ts 396003840380 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2513 prep_new_page mm/page_alloc.c:2520 [inline] get_page_from_freelist+0x31a1/0x3320 mm/page_alloc.c:4279 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5547 __folio_alloc+0xf/0x30 mm/page_alloc.c:5579 vma_alloc_folio+0x486/0x990 mm/mempolicy.c:2243 alloc_page_vma include/linux/gfp.h:284 [inline] wp_page_copy+0x25d/0x18c0 mm/memory.c:3129 handle_pte_fault mm/memory.c:5031 [inline] __handle_mm_fault mm/memory.c:5155 [inline] handle_mm_fault+0x2525/0x5340 mm/memory.c:5276 do_user_addr_fault arch/x86/mm/fault.c:1371 [inline] handle_page_fault arch/x86/mm/fault.c:1462 [inline] exc_page_fault+0x26f/0x660 arch/x86/mm/fault.c:1518 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1440 [inline] free_pcp_prepare mm/page_alloc.c:1490 [inline] free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3358 free_unref_page_list+0x663/0x900 mm/page_alloc.c:3499 release_pages+0x2836/0x2b40 mm/swap.c:1055 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline] tlb_flush_mmu_free mm/mmu_gather.c:254 [inline] tlb_flush_mmu+0xfc/0x210 mm/mmu_gather.c:261 zap_pte_range mm/memory.c:1525 [inline] zap_pmd_range mm/memory.c:1574 [inline] zap_pud_range mm/memory.c:1603 [inline] zap_p4d_range mm/memory.c:1624 [inline] unmap_page_range+0x217c/0x2740 mm/memory.c:1645 unmap_vmas+0x48b/0x640 mm/memory.c:1730 exit_mmap+0x252/0x9f0 mm/mmap.c:3227 __mmput+0x115/0x3c0 kernel/fork.c:1199 exit_mm+0x226/0x300 kernel/exit.c:563 do_exit+0x9f6/0x26a0 kernel/exit.c:856 do_group_exit+0x202/0x2b0 kernel/exit.c:1019 get_signal+0x16f7/0x17d0 kernel/signal.c:2862 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 Memory state around the buggy address: ffff88805155df00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88805155df80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88805155e000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88805155e080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805155e100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================