================================================================== BUG: KASAN: use-after-free in ocfs2_dir_foreach_blk_id fs/ocfs2/dir.c:1787 [inline] BUG: KASAN: use-after-free in ocfs2_dir_foreach_blk+0x1149/0x18a0 fs/ocfs2/dir.c:1925 Read of size 2 at addr ffff8880751e68c9 by task syz.1.159/7081 CPU: 0 UID: 0 PID: 7081 Comm: syz.1.159 Not tainted 6.16.0-rc7-syzkaller-00120-g5f33ebd2018c #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 ocfs2_dir_foreach_blk_id fs/ocfs2/dir.c:1787 [inline] ocfs2_dir_foreach_blk+0x1149/0x18a0 fs/ocfs2/dir.c:1925 ocfs2_readdir+0x254/0x4c0 fs/ocfs2/dir.c:1969 wrap_directory_iterator+0x96/0xe0 fs/readdir.c:65 iterate_dir+0x5af/0x770 fs/readdir.c:108 __do_sys_getdents fs/readdir.c:326 [inline] __se_sys_getdents+0xe4/0x250 fs/readdir.c:312 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc96698e9a9 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:00007fc967769038 EFLAGS: 00000246 ORIG_RAX: 000000000000004e RAX: ffffffffffffffda RBX: 00007fc966bb6080 RCX: 00007fc96698e9a9 RDX: 0000000000000054 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00007fc966a10d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc966bb6080 R15: 00007ffc30fda598 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x167 pfn:0x751e6 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f0(buddy) raw: 00fff00000000000 ffffea0001d92c08 ffffea0001426408 0000000000000000 raw: 0000000000000167 0000000000000001 00000000f0000000 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 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 7065, tgid 7028 (syz.5.156), ts 162524370338, free_ts 163030030904 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x21d5/0x22b0 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419 folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2438 shmem_alloc_folio mm/shmem.c:1851 [inline] shmem_alloc_and_add_folio+0x447/0xf60 mm/shmem.c:1890 shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2536 shmem_get_folio mm/shmem.c:2642 [inline] shmem_write_begin+0xf7/0x2b0 mm/shmem.c:3292 generic_perform_write+0x2c4/0x910 mm/filemap.c:4112 shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3467 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x54b/0xa90 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 7065 tgid 7028 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] free_unref_folios+0xcd2/0x1570 mm/page_alloc.c:2763 folios_put_refs+0x559/0x640 mm/swap.c:992 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x49e/0x14b0 mm/shmem.c:1125 shmem_truncate_range mm/shmem.c:1237 [inline] shmem_evict_inode+0x272/0xa70 mm/shmem.c:1365 evict+0x501/0x9c0 fs/inode.c:810 __dentry_kill+0x209/0x660 fs/dcache.c:669 dput+0x19f/0x2b0 fs/dcache.c:911 __fput+0x68e/0xa70 fs/file_table.c:473 task_work_run+0x1d1/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x6b5/0x22e0 kernel/exit.c:964 do_group_exit+0x21c/0x2d0 kernel/exit.c:1105 get_signal+0x125e/0x1310 kernel/signal.c:3034 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff8880751e6780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880751e6800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8880751e6880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8880751e6900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880751e6980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================