================================================================== BUG: KASAN: use-after-free in ext4_read_inline_data fs/ext4/inline.c:210 [inline] BUG: KASAN: use-after-free in ext4_inlinedir_to_tree+0x4af/0xf50 fs/ext4/inline.c:1402 Read of size 68 at addr ffff888121565ec9 by task syz-executor.0/337 CPU: 0 PID: 337 Comm: syz-executor.0 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+0xee/0x150 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+0x280/0x290 mm/kasan/generic.c:189 memcpy+0x2d/0x70 mm/kasan/shadow.c:65 ext4_read_inline_data fs/ext4/inline.c:210 [inline] ext4_inlinedir_to_tree+0x4af/0xf50 fs/ext4/inline.c:1402 ext4_htree_fill_tree+0x4c5/0x10d0 fs/ext4/namei.c:1211 ext4_dx_readdir fs/ext4/dir.c:608 [inline] ext4_readdir+0x2d8a/0x3c10 fs/ext4/dir.c:145 iterate_dir+0x271/0x610 fs/readdir.c:-1 __do_sys_getdents64 fs/readdir.c:369 [inline] __se_sys_getdents64+0xe5/0x240 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:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7faf166a9363 Code: c1 66 0f 1f 44 00 00 48 83 c4 08 48 89 ef 5b 5d e9 62 8b fa ff 66 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 b0 ff ff ff f7 d8 RSP: 002b:00007ffd42a441a8 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 0000555556d8e890 RCX: 00007faf166a9363 RDX: 0000000000008000 RSI: 0000555556d8e890 RDI: 0000000000000006 RBP: 0000555556d8e864 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000001000 R11: 0000000000000293 R12: ffffffffffffffb0 R13: 0000000000000016 R14: 0000555556d8e860 R15: 0000000000000008 The buggy address belongs to the physical page: page:ffffea0004855940 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x121565 flags: 0x4000000000000000(zone=1) raw: 4000000000000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 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 0x500cc2(GFP_HIGHUSER|__GFP_ACCOUNT), pid 311, tgid 311 (sshd-session), ts 34738788554, free_ts 34738997227 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+0x2c7b/0x2cf0 mm/page_alloc.c:4554 __alloc_pages+0x1c3/0x450 mm/page_alloc.c:5868 __alloc_pages_node include/linux/gfp.h:236 [inline] alloc_pages_node include/linux/gfp.h:259 [inline] alloc_pages include/linux/gfp.h:270 [inline] pipe_write+0x592/0x1950 fs/pipe.c:501 call_write_iter include/linux/fs.h:2282 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x5db/0xca0 fs/read_write.c:584 ksys_write+0x140/0x240 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __x64_sys_write+0x7b/0x90 fs/read_write.c:646 x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 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+0x8f/0x530 mm/page_alloc.c:3687 __folio_put_small mm/swap.c:100 [inline] __folio_put+0xac/0xe0 mm/swap.c:123 folio_put include/linux/mm.h:1442 [inline] put_page include/linux/mm.h:1494 [inline] anon_pipe_buf_release+0x183/0x200 fs/pipe.c:138 pipe_buf_release include/linux/pipe_fs_i.h:199 [inline] pipe_read+0x55d/0x1000 fs/pipe.c:324 call_read_iter include/linux/fs.h:2276 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x41e/0x8c0 fs/read_write.c:470 ksys_read+0x140/0x240 fs/read_write.c:613 __do_sys_read fs/read_write.c:623 [inline] __se_sys_read fs/read_write.c:621 [inline] __x64_sys_read+0x7b/0x90 fs/read_write.c:621 x64_sys_call+0x2f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:1 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff888121565d80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888121565e00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888121565e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888121565f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888121565f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== EXT4-fs error (device loop0): ext4_inlinedir_to_tree:1440: inode #12: block 7: comm syz-executor.0: path /root/syzkaller-testdir285968987/syzkaller.JBZshb/0/file0/file0: bad entry in directory: directory entry overrun - offset=34816, inode=2538880996, rec_len=34812, size=128 fake=0 EXT4-fs error (device loop0): empty_inline_dir:1885: inode #12: block 7: comm syz-executor.0: bad entry in directory: directory entry overrun - offset=4, inode=2538880996, rec_len=34812, size=60 fake=0 EXT4-fs warning (device loop0): empty_inline_dir:1892: bad inline directory (dir #12) - inode 2538880996, rec_len 34812, name_len 234inline size 60 EXT4-fs error (device loop0): ext4_inlinedir_to_tree:1440: inode #12: block 7: comm syz-executor.0: path /root/syzkaller-testdir285968987/syzkaller.JBZshb/0/file0/file0: bad entry in directory: directory entry overrun - offset=34816, inode=2538880996, rec_len=34812, size=128 fake=0 EXT4-fs error (device loop0): empty_inline_dir:1885: inode #12: block 7: comm syz-executor.0: bad entry in directory: directory entry overrun - offset=4, inode=2538880996, rec_len=34812, size=60 fake=0 EXT4-fs warning (device loop0): empty_inline_dir:1892: bad inline directory (dir #12) - inode 2538880996, rec_len 34812, name_len 234inline size 60 EXT4-fs error (device loop0): ext4_inlinedir_to_tree:1440: inode #12: block 7: comm syz-executor.0: path /root/syzkaller-testdir285968987/syzkaller.JBZshb/0/file0/file0: bad entry in directory: directory entry overrun - offset=34816, inode=2538880996, rec_len=34812, size=128 fake=0 EXT4-fs error (device loop0): empty_inline_dir:1885: inode #12: block 7: comm syz-executor.0: bad entry in directory: directory entry overrun - offset=4, inode=2538880996, rec_len=34812, size=60 fake=0 EXT4-fs warning (device loop0): empty_inline_dir:1892: bad inline directory (dir #12) - inode 2538880996, rec_len 34812, name_len 234inline size 60 EXT4-fs error (device loop0): ext4_inlinedir_to_tree:1440: inode #12: block 7: comm syz-executor.0: path /root/syzkaller-testdir285968987/syzkaller.JBZshb/0/file0/file0: bad entry in directory: directory entry overrun - offset=34816, inode=2538880996, rec_len=34812, size=128 fake=0 EXT4-fs error (device loop0): empty_inline_dir:1885: inode #12: block 7: comm syz-executor.0: bad entry in directory: directory entry overrun - offset=4, inode=2538880996, rec_len=34812, size=60 fake=0 EXT4-fs warning (device loop0): empty_inline_dir:1892: bad inline directory (dir #12) - inode 2538880996, rec_len 34812, name_len 234inline size 60 EXT4-fs error (device loop0): ext4_inlinedir_to_tree:1440: inode #12: block 7: comm syz-executor.0: path /root/syzkaller-testdir285968987/syzkaller.JBZshb/0/file0/file0: bad entry in directory: directory entry overrun - offset=34816, inode=2538880996, rec_len=34812, size=128 fake=0 EXT4-fs error (device loop0): empty_inline_dir:1885: inode #12: block 7: comm syz-executor.0: bad entry in directory: directory entry overrun - offset=4, inode=2538880996, rec_len=34812, size=60 fake=0 EXT4-fs warning (device loop0): empty_inline_dir:1892: bad inline directory (dir #12) - inode 2538880996, rec_len 34812, name_len 234inline size 60 EXT4-fs warning (device loop0): empty_inline_dir:1892: bad inline directory (dir #12) - inode 2538880996, rec_len 34812, name_len 234inline size 60 EXT4-fs warning (device loop0): empty_inline_dir:1892: bad inline directory (dir #12) - inode 2538880996, rec_len 34812, name_len 234inline size 60 EXT4-fs warning (device loop0): empty_inline_dir:1892: bad inline directory (dir #12) - inode 2538880996, rec_len 34812, name_len 234inline size 60 EXT4-fs warning (device loop0): empty_inline_dir:1892: bad inline directory (dir #12) - inode 2538880996, rec_len 34812, name_len 234inline size 60 EXT4-fs warning (device loop0): empty_inline_dir:1892: bad inline directory (dir #12) - inode 2538880996, rec_len 34812, name_len 234inline size 60 EXT4-fs (loop0): unmounting filesystem.