EXT4-fs error (device loop6): ext4_orphan_get:1400: inode #15: comm syz.6.3044: 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+0xa6/0x480 kernel/time/timer.c:611 Write of size 8 at addr ffff8881098b24c0 by task syz.6.3044/13499 CPU: 1 PID: 13499 Comm: syz.6.3044 Not tainted 6.1.128-syzkaller-00009-g70d032fba5f4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x151/0x1b7 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0x158/0x4e0 mm/kasan/report.c:427 kasan_report+0x13c/0x170 mm/kasan/report.c:531 __asan_report_store8_noabort+0x17/0x20 mm/kasan/report_generic.c:356 hlist_add_head include/linux/list.h:930 [inline] enqueue_timer+0xa6/0x480 kernel/time/timer.c:611 internal_add_timer kernel/time/timer.c:640 [inline] __mod_timer+0x8d3/0xcf0 kernel/time/timer.c:1121 mod_timer+0x1f/0x30 kernel/time/timer.c:1172 ext4_update_super+0xa41/0xe50 fs/ext4/super.c:6056 ext4_commit_super+0xe3/0x4b0 fs/ext4/super.c:6075 ext4_handle_error+0x5d8/0x870 fs/ext4/super.c:678 __ext4_error_inode+0x327/0x5e0 fs/ext4/super.c:811 __ext4_iget+0x2c5e/0x3ee0 ext4_orphan_get+0x1c2/0x5f0 fs/ext4/ialloc.c:1400 ext4_orphan_cleanup+0x901/0x11b0 fs/ext4/orphan.c:467 __ext4_fill_super fs/ext4/super.c:5510 [inline] ext4_fill_super+0x7d55/0x8450 fs/ext4/super.c:5641 get_tree_bdev+0x440/0x680 fs/super.c:1368 ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5671 vfs_get_tree+0x88/0x290 fs/super.c:1575 do_new_mount+0x2ba/0xb30 fs/namespace.c:3056 path_mount+0x671/0x1070 fs/namespace.c:3386 do_mount fs/namespace.c:3399 [inline] __do_sys_mount fs/namespace.c:3607 [inline] __se_sys_mount+0x2c4/0x3b0 fs/namespace.c:3584 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3584 x64_sys_call+0x49d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fb1f538e90a 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:00007fb1f62c8e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fb1f62c8ef0 RCX: 00007fb1f538e90a RDX: 0000400000000180 RSI: 00004000000001c0 RDI: 00007fb1f62c8eb0 RBP: 0000400000000180 R08: 00007fb1f62c8ef0 R09: 0000000000000800 R10: 0000000000000800 R11: 0000000000000246 R12: 00004000000001c0 R13: 00007fb1f62c8eb0 R14: 000000000000049b R15: 0000400000000700 Allocated by task 13313: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:379 [inline] __kasan_kmalloc+0x9c/0xb0 mm/kasan/common.c:388 kasan_kmalloc include/linux/kasan.h:212 [inline] kmalloc_trace+0x44/0xa0 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:4253 [inline] ext4_fill_super+0x102/0x8450 fs/ext4/super.c:5628 get_tree_bdev+0x440/0x680 fs/super.c:1368 ext4_get_tree+0x1c/0x20 fs/ext4/super.c:5671 vfs_get_tree+0x88/0x290 fs/super.c:1575 do_new_mount+0x2ba/0xb30 fs/namespace.c:3056 path_mount+0x671/0x1070 fs/namespace.c:3386 do_mount fs/namespace.c:3399 [inline] __do_sys_mount fs/namespace.c:3607 [inline] __se_sys_mount+0x2c4/0x3b0 fs/namespace.c:3584 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3584 x64_sys_call+0x49d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 294: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0x131/0x180 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:1745 [inline] slab_free_freelist_hook mm/slub.c:1771 [inline] slab_free mm/slub.c:3686 [inline] __kmem_cache_free+0x21d/0x410 mm/slub.c:3702 kfree+0x7a/0xf0 mm/slab_common.c:990 ext4_put_super+0x9e5/0xd60 fs/ext4/super.c:1313 generic_shutdown_super+0x14f/0x370 fs/super.c:503 kill_block_super+0x7e/0xe0 fs/super.c:1472 deactivate_locked_super+0xad/0x110 fs/super.c:334 deactivate_super+0xbe/0xf0 fs/super.c:365 cleanup_mnt+0x485/0x510 fs/namespace.c:1186 __cleanup_mnt+0x19/0x20 fs/namespace.c:1193 task_work_run+0x24d/0x2e0 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0xbd0/0x2b80 kernel/exit.c:877 do_group_exit+0x21a/0x2d0 kernel/exit.c:1027 __do_sys_exit_group kernel/exit.c:1038 [inline] __se_sys_exit_group kernel/exit.c:1036 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1036 x64_sys_call+0x610/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff8881098b2000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 1216 bytes inside of 4096-byte region [ffff8881098b2000, ffff8881098b3000) The buggy address belongs to the physical page: page:ffffea0004262c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1098b0 head:ffffea0004262c00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 0000000000000000 dead000000000001 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 1125, tgid 1118 (syz.1.173), ts 101250934633, free_ts 100810174389 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x213/0x220 mm/page_alloc.c:2637 prep_new_page+0x1b/0x110 mm/page_alloc.c:2644 get_page_from_freelist+0x3a98/0x3b10 mm/page_alloc.c:4539 __alloc_pages+0x234/0x610 mm/page_alloc.c:5837 alloc_slab_page+0x6c/0xf0 allocate_slab mm/slub.c:1962 [inline] new_slab+0x90/0x3e0 mm/slub.c:2015 ___slab_alloc+0x6f9/0xb80 mm/slub.c:3203 __slab_alloc+0x5d/0xa0 mm/slub.c:3302 slab_alloc_node mm/slub.c:3387 [inline] __kmem_cache_alloc_node+0x207/0x2a0 mm/slub.c:3462 kmalloc_trace+0x2a/0xa0 mm/slab_common.c:1028 kmalloc include/linux/slab.h:563 [inline] copy_mount_options fs/namespace.c:3264 [inline] __do_sys_mount fs/namespace.c:3602 [inline] __se_sys_mount+0x156/0x3b0 fs/namespace.c:3584 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3584 x64_sys_call+0x49d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 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:1545 [inline] free_pcp_prepare mm/page_alloc.c:1619 [inline] free_unref_page_prepare+0x9f1/0xa00 mm/page_alloc.c:3581 free_unref_page+0xb2/0x5c0 mm/page_alloc.c:3677 free_the_page mm/page_alloc.c:830 [inline] free_compound_page+0x9d/0xd0 mm/page_alloc.c:853 destroy_large_folio+0x56/0x90 mm/page_alloc.c:890 __folio_put_large mm/swap.c:110 [inline] __folio_put+0xcf/0xe0 mm/swap.c:118 folio_put include/linux/mm.h:1431 [inline] put_page include/linux/mm.h:1483 [inline] page_to_skb+0x7c1/0xbe0 drivers/net/virtio_net.c:556 receive_mergeable drivers/net/virtio_net.c:1128 [inline] receive_buf+0x4fc/0x5000 drivers/net/virtio_net.c:1267 virtnet_receive drivers/net/virtio_net.c:1562 [inline] virtnet_poll+0x6d5/0x1450 drivers/net/virtio_net.c:1680 __napi_poll+0xbe/0x5c0 net/core/dev.c:6563 napi_poll net/core/dev.c:6630 [inline] net_rx_action+0x595/0xdd0 net/core/dev.c:6744 handle_softirqs+0x1db/0x650 kernel/softirq.c:624 __do_softirq+0xb/0xd kernel/softirq.c:662 Memory state around the buggy address: ffff8881098b2380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881098b2400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881098b2480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881098b2500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881098b2580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== EXT4-fs error (device loop6): ext4_orphan_get:1405: comm syz.6.3044: couldn't read orphan inode 15 (err -117) EXT4-fs (loop6): mounted filesystem without journal. Quota mode: writeback.