EXT4-fs warning (device loop3): dx_probe:892: inode #2: comm syz.3.528: dx entry: limit 0 != root limit 124 EXT4-fs warning (device loop3): dx_probe:965: inode #2: comm syz.3.528: 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 ffff88805b9dd003 by task syz.3.528/5658 CPU: 0 PID: 5658 Comm: syz.3.528 Not tainted 6.1.97-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 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: 0033:0x7f1fa3575bd9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f1fa438f048 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007f1fa3703f60 RCX: 00007f1fa3575bd9 RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000008 RBP: 00007f1fa35e4e60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f1fa3703f60 R15: 00007ffc06d38458 The buggy address belongs to the physical page: page:ffffea00016e7740 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5b9dd flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea000149f388 ffffea00015475c8 0000000000000000 raw: 0000000000000000 ffff8880797ebae0 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x500dc0(GFP_USER|__GFP_ZERO|__GFP_ACCOUNT), pid 5650, tgid 5650 (syz-executor), ts 181244399686, free_ts 181412420598 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2517 prep_new_page mm/page_alloc.c:2524 [inline] get_page_from_freelist+0x322e/0x33b0 mm/page_alloc.c:4283 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5551 __pte_alloc_one include/asm-generic/pgalloc.h:63 [inline] pte_alloc_one+0x86/0x360 arch/x86/mm/pgtable.c:33 do_fault_around mm/memory.c:4576 [inline] do_read_fault mm/memory.c:4607 [inline] do_fault mm/memory.c:4741 [inline] handle_pte_fault mm/memory.c:5013 [inline] __handle_mm_fault mm/memory.c:5155 [inline] handle_mm_fault+0x331a/0x5340 mm/memory.c:5276 do_user_addr_fault arch/x86/mm/fault.c:1340 [inline] handle_page_fault arch/x86/mm/fault.c:1431 [inline] exc_page_fault+0x26f/0x620 arch/x86/mm/fault.c:1487 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:1444 [inline] free_pcp_prepare mm/page_alloc.c:1494 [inline] free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3362 free_unref_page_list+0x663/0x900 mm/page_alloc.c:3503 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 tlb_finish_mmu+0xce/0x1f0 mm/mmu_gather.c:361 exit_mmap+0x3c3/0x9f0 mm/mmap.c:3239 __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 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 Memory state around the buggy address: ffff88805b9dcf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88805b9dcf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88805b9dd000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88805b9dd080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805b9dd100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================