================================================================== 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+0x508/0xfe0 fs/ext4/inline.c:1433 Read of size 52 at addr ffff88811c139b97 by task syz.2.17/479 CPU: 1 PID: 479 Comm: syz.2.17 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:88 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0xf1/0x140 mm/kasan/report.c:444 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_inlinedir_to_tree+0x508/0xfe0 fs/ext4/inline.c:1433 ext4_htree_fill_tree+0x508/0x1160 fs/ext4/namei.c:1211 ext4_dx_readdir fs/ext4/dir.c:609 [inline] ext4_readdir+0x2cdb/0x3b20 fs/ext4/dir.c:145 iterate_dir+0x260/0x600 fs/readdir.c:-1 __do_sys_getdents fs/readdir.c:286 [inline] __se_sys_getdents+0xf2/0x250 fs/readdir.c:271 __x64_sys_getdents+0x7b/0x90 fs/readdir.c:271 x64_sys_call+0xb4/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:79 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f46aa2d4cb9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f46aa139028 EFLAGS: 00000246 ORIG_RAX: 000000000000004e RAX: ffffffffffffffda RBX: 00007f46aa54ffa0 RCX: 00007f46aa2d4cb9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 00007f46aa342bf7 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f46aa550038 R14: 00007f46aa54ffa0 R15: 00007ffe815807b8 Allocated by task 403: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:433 [inline] __kasan_slab_alloc+0xbd/0xf0 mm/kasan/common.c:466 kasan_slab_alloc include/linux/kasan.h:217 [inline] slab_post_alloc_hook+0x4f/0x2b0 mm/slab.h:550 slab_alloc_node mm/slub.c:3245 [inline] slab_alloc mm/slub.c:3255 [inline] kmem_cache_alloc+0xf7/0x260 mm/slub.c:3260 vm_area_dup+0x26/0x210 kernel/fork.c:368 __split_vma+0xac/0x3e0 mm/mmap.c:2753 __do_munmap+0x3b9/0x1020 mm/mmap.c:2882 __vm_munmap+0x163/0x2b0 mm/mmap.c:2978 __do_sys_munmap mm/mmap.c:3004 [inline] __se_sys_munmap mm/mmap.c:3000 [inline] __x64_sys_munmap+0x6b/0x80 mm/mmap.c:3000 x64_sys_call+0xc9/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:12 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 20: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4a/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:365 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:373 kasan_slab_free include/linux/kasan.h:193 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1754 slab_free mm/slub.c:3526 [inline] kmem_cache_free+0x100/0x320 mm/slub.c:3544 __free_vm_area_struct+0x1c/0x20 kernel/fork.c:390 rcu_do_batch+0x532/0xbe0 kernel/rcu/tree.c:2523 rcu_core+0x5ee/0xf80 kernel/rcu/tree.c:2763 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2776 handle_softirqs+0x250/0x560 kernel/softirq.c:583 __do_softirq+0xb/0xd kernel/softirq.c:621 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 __call_rcu_common kernel/rcu/tree.c:3011 [inline] call_rcu+0x10b/0xf80 kernel/rcu/tree.c:3129 free_vm_area_struct kernel/fork.c:395 [inline] vm_area_free_no_check+0x10e/0x140 kernel/fork.c:409 vm_area_free+0x56/0x60 kernel/fork.c:419 remove_vma mm/mmap.c:191 [inline] remove_vma_list mm/mmap.c:2651 [inline] __do_munmap+0xc3d/0x1020 mm/mmap.c:2928 __vm_munmap+0x163/0x2b0 mm/mmap.c:2978 __do_sys_munmap mm/mmap.c:3004 [inline] __se_sys_munmap mm/mmap.c:3000 [inline] __x64_sys_munmap+0x6b/0x80 mm/mmap.c:3000 x64_sys_call+0xc9/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:12 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88811c139b90 which belongs to the cache vm_area_struct of size 232 The buggy address is located 7 bytes inside of 232-byte region [ffff88811c139b90, ffff88811c139c78) The buggy address belongs to the page: page:ffffea0004704e40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11c139 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 0000000000000000 dead000000000122 ffff888100187980 raw: 0000000000000000 00000000000d000d 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 403, ts 46588711772, free_ts 45669955416 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605 prep_new_page+0x1c/0x110 mm/page_alloc.c:2611 get_page_from_freelist+0x2d3a/0x2dc0 mm/page_alloc.c:4485 __alloc_pages+0x1a2/0x460 mm/page_alloc.c:5808 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1937 [inline] new_slab+0xa1/0x4d0 mm/slub.c:2000 ___slab_alloc+0x381/0x810 mm/slub.c:3033 __slab_alloc+0x49/0x90 mm/slub.c:3120 slab_alloc_node mm/slub.c:3211 [inline] slab_alloc mm/slub.c:3255 [inline] kmem_cache_alloc+0x138/0x260 mm/slub.c:3260 vm_area_alloc+0x24/0x130 kernel/fork.c:360 __mmap_region mm/mmap.c:1794 [inline] mmap_region+0xaa6/0x1710 mm/mmap.c:2959 do_mmap+0x812/0xf10 mm/mmap.c:1598 vm_mmap_pgoff+0x1ec/0x430 mm/util.c:555 ksys_mmap_pgoff+0xf6/0x1d0 mm/mmap.c:1647 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:93 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:86 [inline] __x64_sys_mmap+0xfa/0x110 arch/x86/kernel/sys_x86_64.c:86 x64_sys_call+0x83/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:10 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1472 [inline] free_pcp_prepare mm/page_alloc.c:1544 [inline] free_unref_page_prepare+0x542/0x550 mm/page_alloc.c:3534 free_unref_page+0xae/0x540 mm/page_alloc.c:3616 free_the_page mm/page_alloc.c:805 [inline] __free_pages+0x6c/0x100 mm/page_alloc.c:5884 __vunmap+0x86d/0xa00 mm/vmalloc.c:2660 __vfree mm/vmalloc.c:2709 [inline] vfree+0x8b/0xc0 mm/vmalloc.c:2740 kcov_put kernel/kcov.c:417 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:519 __fput+0x20b/0x8b0 fs/file_table.c:311 ____fput+0x15/0x20 fs/file_table.c:339 task_work_run+0x127/0x190 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0xa9e/0x27e0 kernel/exit.c:889 do_group_exit+0x141/0x310 kernel/exit.c:1003 get_signal+0x66a/0x1480 kernel/signal.c:2907 arch_do_signal_or_restart+0xdf/0x11c0 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0xa7/0xe0 kernel/entry/common.c:178 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307 Memory state around the buggy address: ffff88811c139a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88811c139b00: fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc >ffff88811c139b80: fc fc fa fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88811c139c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc ffff88811c139c80: fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb fb ================================================================== EXT4-fs error (device loop2): ext4_inlinedir_to_tree:1471: inode #12: block 7: comm syz.2.17: path /0/file1/file0: bad entry in directory: rec_len % 4 != 0 - offset=35110, inode=3517778242, rec_len=35106, size=112 fake=0 EXT4-fs (loop2): Remounting filesystem read-only