EXT4-fs error (device loop5): ext4_orphan_get:1400: inode #15: comm syz.5.70: casefold flag without casefold feature ================================================================== BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:930 [inline] BUG: KASAN: use-after-free in enqueue_timer+0xae/0x480 kernel/time/timer.c:611 Write of size 8 at addr ffff88811bac64c0 by task syz.5.70/643 CPU: 1 PID: 643 Comm: syz.5.70 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 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 __asan_report_store8_noabort+0x17/0x20 mm/kasan/report_generic.c:356 hlist_add_head include/linux/list.h:930 [inline] enqueue_timer+0xae/0x480 kernel/time/timer.c:611 __mod_timer+0x79f/0xb30 kernel/time/timer.c:-1 mod_timer+0x1f/0x30 kernel/time/timer.c:1172 ext4_update_super+0xa54/0xe40 fs/ext4/super.c:6070 ext4_commit_super+0xe3/0x4b0 fs/ext4/super.c:6089 ext4_handle_error+0x5c8/0x860 fs/ext4/super.c:678 __ext4_error_inode+0x2ce/0x560 fs/ext4/super.c:811 __ext4_iget+0x2a38/0x3d70 fs/ext4/inode.c:-1 ext4_orphan_get+0x1d1/0x620 fs/ext4/ialloc.c:1400 ext4_orphan_cleanup+0x9b5/0x1210 fs/ext4/orphan.c:467 __ext4_fill_super fs/ext4/super.c:5524 [inline] ext4_fill_super+0x7439/0x7970 fs/ext4/super.c:5655 get_tree_bdev+0x444/0x680 fs/super.c:1368 ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5685 vfs_get_tree+0x9a/0x270 fs/super.c:1575 do_new_mount+0x25a/0xa20 fs/namespace.c:3069 path_mount+0x675/0x1010 fs/namespace.c:3399 do_mount fs/namespace.c:3412 [inline] __do_sys_mount fs/namespace.c:3620 [inline] __se_sys_mount+0x318/0x380 fs/namespace.c:3597 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3597 x64_sys_call+0x65d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166 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: 0033:0x7f3dc019076a Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f3dc0f56e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f3dc0f56ef0 RCX: 00007f3dc019076a RDX: 0000200000000180 RSI: 00002000000001c0 RDI: 00007f3dc0f56eb0 RBP: 0000200000000180 R08: 00007f3dc0f56ef0 R09: 0000000000800714 R10: 0000000000800714 R11: 0000000000000246 R12: 00002000000001c0 R13: 00007f3dc0f56eb0 R14: 0000000000000485 R15: 0000200000000000 Allocated by task 506: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:379 [inline] __kasan_kmalloc+0x95/0xb0 mm/kasan/common.c:388 kasan_kmalloc include/linux/kasan.h:212 [inline] kmalloc_trace+0x40/0xb0 mm/slab_common.c:1033 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] ext4_alloc_sbi fs/ext4/super.c:4263 [inline] ext4_fill_super+0x107/0x7970 fs/ext4/super.c:5642 get_tree_bdev+0x444/0x680 fs/super.c:1368 ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5685 vfs_get_tree+0x9a/0x270 fs/super.c:1575 do_new_mount+0x25a/0xa20 fs/namespace.c:3069 path_mount+0x675/0x1010 fs/namespace.c:3399 do_mount fs/namespace.c:3412 [inline] __do_sys_mount fs/namespace.c:3620 [inline] __se_sys_mount+0x318/0x380 fs/namespace.c:3597 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3597 x64_sys_call+0x65d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166 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 Freed by task 287: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x31/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:241 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:249 kasan_slab_free include/linux/kasan.h:178 [inline] slab_free_hook mm/slub.c:1750 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1776 slab_free mm/slub.c:3712 [inline] __kmem_cache_free+0xb7/0x1b0 mm/slub.c:3728 kfree+0x6f/0xf0 mm/slab_common.c:990 ext4_put_super+0x9b6/0xac0 fs/ext4/super.c:1313 generic_shutdown_super+0x15f/0x370 fs/super.c:503 kill_block_super+0x7f/0xf0 fs/super.c:1472 deactivate_locked_super+0xb5/0x120 fs/super.c:334 deactivate_super+0xaf/0xe0 fs/super.c:365 cleanup_mnt+0x45f/0x4e0 fs/namespace.c:1182 __cleanup_mnt+0x19/0x20 fs/namespace.c:1189 task_work_run+0x1db/0x240 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0xa25/0x2650 kernel/exit.c:886 do_group_exit+0x210/0x2d0 kernel/exit.c:1028 __do_sys_exit_group kernel/exit.c:1039 [inline] __se_sys_exit_group kernel/exit.c:1037 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1037 x64_sys_call+0x7b4/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:232 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 The buggy address belongs to the object at ffff88811bac6000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 1216 bytes inside of 4096-byte region [ffff88811bac6000, ffff88811bac7000) The buggy address belongs to the physical page: page:ffffea00046eb000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11bac0 head:ffffea00046eb000 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 ffffea00046eac00 dead000000000003 ffff888100043380 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 103, tgid 103 (udevd), ts 6677044663, free_ts 0 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_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3d0 mm/slub.c:2020 ___slab_alloc+0x6bd/0xb20 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] __kmem_cache_alloc_node+0x203/0x2c0 mm/slub.c:3423 __do_kmalloc_node mm/slab_common.c:937 [inline] __kmalloc_node+0xa1/0x1e0 mm/slab_common.c:945 kmalloc_node include/linux/slab.h:589 [inline] kvmalloc_node+0x294/0x480 mm/util.c:592 kvmalloc include/linux/slab.h:716 [inline] seq_buf_alloc fs/seq_file.c:38 [inline] seq_read_iter+0x1fc/0xdd0 fs/seq_file.c:210 kernfs_fop_read_iter+0x147/0x480 fs/kernfs/file.c:279 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 page_owner free stack trace missing Memory state around the buggy address: ffff88811bac6380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88811bac6400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88811bac6480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88811bac6500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88811bac6580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== EXT4-fs error (device loop5): ext4_orphan_get:1405: comm syz.5.70: couldn't read orphan inode 15 (err -117) EXT4-fs (loop5): mounted filesystem without journal. Quota mode: writeback.