================================================================== BUG: KASAN: use-after-free in ext4_read_inline_data fs/ext4/inline.c:210 [inline] BUG: KASAN: use-after-free in ext4_read_inline_dir+0x449/0xe60 fs/ext4/inline.c:1530 Read of size 68 at addr ffff88812a316d05 by task syz-executor/472 CPU: 1 PID: 472 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x249/0x2a0 mm/kasan/generic.c:189 memcpy+0x2d/0x70 mm/kasan/shadow.c:65 ext4_read_inline_data fs/ext4/inline.c:210 [inline] ext4_read_inline_dir+0x449/0xe60 fs/ext4/inline.c:1530 ext4_readdir+0x3c6/0x3e10 fs/ext4/dir.c:161 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: 0033:0x7f63c87b8d73 Code: c7 c0 e8 ff ff ff 64 c7 00 16 00 00 00 31 c0 eb 9e e8 81 9b fd ff 90 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 c7 c2 e8 ff ff ff f7 d8 RSP: 002b:00007ffe172b59b8 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 000055555c48f950 RCX: 00007f63c87b8d73 RDX: 0000000000008000 RSI: 000055555c48f980 RDI: 0000000000000006 RBP: 000055555c48f980 R08: 00007f63c8963ca0 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000293 R12: 000055555c48f954 R13: ffffffffffffffe8 R14: 0000000000000016 R15: 0000000000000001 The buggy address belongs to the physical page: page:ffffea0004a8c580 refcount:1 mapcount:0 mapping:ffff8881246658c0 index:0x43 pfn:0x12a316 memcg:ffff88812df01380 aops:ext4_da_aops ino:7f4 dentry name(?):"syz.BtxUMT" flags: 0x6000000000000014(uptodate|lru|zone=1) raw: 6000000000000014 ffffea0004a8c548 ffffea0004a8c5c8 ffff8881246658c0 raw: 0000000000000043 0000000000000000 00000001ffffffff ffff88812df01380 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Movable, gfp_mask 0x152c4a(GFP_NOFS|__GFP_HIGHMEM|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL|__GFP_MOVABLE), pid 534, tgid 534 (syz.2.18), ts 56652167581, free_ts 53489357125 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2643 prep_new_page+0x1c/0x110 mm/page_alloc.c:2650 get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4554 __alloc_pages+0x1d9/0x480 mm/page_alloc.c:5868 __folio_alloc+0x12/0x40 mm/page_alloc.c:5900 __folio_alloc_node include/linux/gfp.h:245 [inline] folio_alloc include/linux/gfp.h:274 [inline] filemap_alloc_folio include/linux/pagemap.h:515 [inline] page_cache_ra_unbounded+0x248/0x730 mm/readahead.c:260 do_page_cache_ra mm/readahead.c:312 [inline] page_cache_ra_order+0x389/0xb90 mm/readahead.c:576 do_sync_mmap_readahead+0x76e/0x9d0 mm/filemap.c:3192 filemap_fault+0x3de/0x1260 mm/filemap.c:3289 __do_fault mm/memory.c:4373 [inline] do_shared_fault mm/memory.c:4801 [inline] do_fault+0xad3/0x1e20 mm/memory.c:4879 handle_pte_fault mm/memory.c:5171 [inline] __handle_mm_fault mm/memory.c:5313 [inline] handle_mm_fault+0x133a/0x26c0 mm/memory.c:5453 do_user_addr_fault+0x905/0x1050 arch/x86/mm/fault.c:1323 handle_page_fault arch/x86/mm/fault.c:1466 [inline] exc_page_fault+0x51/0xb0 arch/x86/mm/fault.c:1522 asm_exc_page_fault+0x27/0x30 arch/x86/include/asm/idtentry.h:608 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1551 [inline] free_pcp_prepare mm/page_alloc.c:1625 [inline] free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3589 free_unref_page_list+0x117/0x8c0 mm/page_alloc.c:3740 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 exit_mm kernel/exit.c:568 [inline] do_exit+0x994/0x2660 kernel/exit.c:873 do_group_exit+0x210/0x2d0 kernel/exit.c:1028 get_signal+0x13b5/0x1520 kernel/signal.c:2891 arch_do_signal_or_restart+0xd1/0x1140 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x7a/0xb0 kernel/entry/common.c:174 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 Memory state around the buggy address: ffff88812a316c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88812a316c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88812a316d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff88812a316d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88812a316e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== EXT4-fs error (device loop4): ext4_read_inline_dir:1611: inode #12: block 5: comm syz-executor: path /0/file0/file0: bad entry in directory: rec_len % 4 != 0 - offset=24, inode=1633771873, rec_len=24929, size=148 fake=0 EXT4-fs error (device loop4): ext4_read_inline_dir:1611: inode #12: block 5: comm syz-executor: path /0/file0/file0: bad entry in directory: rec_len % 4 != 0 - offset=24, inode=1633771873, rec_len=24929, size=148 fake=0 EXT4-fs error (device loop4): empty_inline_dir:1895: inode #12: block 5: comm syz-executor: bad entry in directory: rec_len % 4 != 0 - offset=4, inode=1633771873, rec_len=24929, size=60 fake=0 EXT4-fs warning (device loop4): empty_inline_dir:1902: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60 EXT4-fs error (device loop4): ext4_read_inline_dir:1611: inode #12: block 5: comm syz-executor: path /0/file0/file0: bad entry in directory: rec_len % 4 != 0 - offset=24, inode=1633771873, rec_len=24929, size=148 fake=0 EXT4-fs error (device loop4): ext4_read_inline_dir:1611: inode #12: block 5: comm syz-executor: path /0/file0/file0: bad entry in directory: rec_len % 4 != 0 - offset=24, inode=1633771873, rec_len=24929, size=148 fake=0 EXT4-fs error (device loop4): empty_inline_dir:1895: inode #12: block 5: comm syz-executor: bad entry in directory: rec_len % 4 != 0 - offset=4, inode=1633771873, rec_len=24929, size=60 fake=0 EXT4-fs warning (device loop4): empty_inline_dir:1902: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60 EXT4-fs error (device loop4): ext4_read_inline_dir:1611: inode #12: block 5: comm syz-executor: path /0/file0/file0: bad entry in directory: rec_len % 4 != 0 - offset=24, inode=1633771873, rec_len=24929, size=148 fake=0 EXT4-fs error (device loop4): ext4_read_inline_dir:1611: inode #12: block 5: comm syz-executor: path /0/file0/file0: bad entry in directory: rec_len % 4 != 0 - offset=24, inode=1633771873, rec_len=24929, size=148 fake=0 EXT4-fs error (device loop4): empty_inline_dir:1895: inode #12: block 5: comm syz-executor: bad entry in directory: rec_len % 4 != 0 - offset=4, inode=1633771873, rec_len=24929, size=60 fake=0 EXT4-fs warning (device loop4): empty_inline_dir:1902: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60 EXT4-fs warning (device loop4): empty_inline_dir:1902: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60 EXT4-fs warning (device loop4): empty_inline_dir:1902: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60 EXT4-fs warning (device loop4): empty_inline_dir:1902: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60 EXT4-fs warning (device loop4): empty_inline_dir:1902: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60 EXT4-fs warning (device loop4): empty_inline_dir:1902: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60 EXT4-fs warning (device loop4): empty_inline_dir:1902: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60 EXT4-fs warning (device loop4): empty_inline_dir:1902: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60 EXT4-fs (loop4): unmounting filesystem.