loop6: detected capacity change from 0 to 32768 ================================================================== BUG: KASAN: slab-use-after-free in dtMoveEntry fs/jfs/jfs_dtree.c:3931 [inline] BUG: KASAN: slab-use-after-free in dtSplitPage+0x1bce/0x36a0 fs/jfs/jfs_dtree.c:1558 Write of size 1 at addr ffff8880290e7000 by task syz.6.1183/12669 CPU: 1 UID: 0 PID: 12669 Comm: syz.6.1183 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 dtMoveEntry fs/jfs/jfs_dtree.c:3931 [inline] dtSplitPage+0x1bce/0x36a0 fs/jfs/jfs_dtree.c:1558 dtSplitUp fs/jfs/jfs_dtree.c:1089 [inline] dtInsert+0x1080/0x5cb0 fs/jfs/jfs_dtree.c:868 jfs_mkdir+0x76b/0xb00 fs/jfs/namei.c:271 vfs_mkdir+0x406/0x620 fs/namei.c:5276 filename_mkdirat+0x285/0x510 fs/namei.c:5309 __do_sys_mkdirat fs/namei.c:5330 [inline] __se_sys_mkdirat+0x35/0x150 fs/namei.c:5327 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4b7139cf47 Code: 00 66 90 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 db f7 ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 b8 02 01 00 00 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:00007f4b72193e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f4b72193ee0 RCX: 00007f4b7139cf47 RDX: 00000000000001ff RSI: 0000200000000580 RDI: 00000000ffffff9c RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000580 R13: 00007f4b72193ea0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 11839: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4584 [inline] slab_alloc_node mm/slub.c:4917 [inline] kmem_cache_alloc_noprof+0x2a0/0x5f0 mm/slub.c:4931 prepare_creds+0x30/0x820 kernel/cred.c:185 copy_creds+0x109/0x9f0 kernel/cred.c:286 copy_process+0xd1f/0x4390 kernel/fork.c:2153 kernel_clone+0x2d7/0x940 kernel/fork.c:2748 __do_sys_clone kernel/fork.c:2889 [inline] __se_sys_clone kernel/fork.c:2873 [inline] __x64_sys_clone+0x1b6/0x230 kernel/fork.c:2873 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 10878: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2677 [inline] slab_free mm/slub.c:6377 [inline] kmem_cache_free+0x182/0x650 mm/slub.c:6504 rcu_do_batch kernel/rcu/tree.c:2645 [inline] rcu_core+0x78b/0x10a0 kernel/rcu/tree.c:2897 handle_softirqs+0x225/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3159 [inline] call_rcu+0xee/0x8b0 kernel/rcu/tree.c:3279 exit_creds+0x146/0x1c0 kernel/cred.c:-1 __put_task_struct+0x133/0x4a0 kernel/fork.c:792 rcu_do_batch kernel/rcu/tree.c:2645 [inline] rcu_core+0x78b/0x10a0 kernel/rcu/tree.c:2897 handle_softirqs+0x225/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 The buggy address belongs to the object at ffff8880290e7000 which belongs to the cache cred of size 184 The buggy address is located 0 bytes inside of freed 184-byte region [ffff8880290e7000, ffff8880290e70b8) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880290e7500 pfn:0x290e7 memcg:ffff888052c99001 flags: 0xfff00000000200(workingset|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000200 ffff88801c2f63c0 ffffea0000a22590 ffffea0000b20250 raw: ffff8880290e7500 0000000800100004 00000000f5000000 ffff888052c99001 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 133, tgid 133 (kworker/u8:5), ts 6467722933, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0x21fa/0x2270 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3266 [inline] allocate_slab+0x79/0x5e0 mm/slub.c:3380 new_slab mm/slub.c:3426 [inline] refill_objects+0x2d5/0x350 mm/slub.c:7310 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x2bf/0x6b0 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] kmem_cache_alloc_noprof+0x382/0x5f0 mm/slub.c:4931 prepare_creds+0x30/0x820 kernel/cred.c:185 copy_creds+0x109/0x9f0 kernel/cred.c:286 copy_process+0xd1f/0x4390 kernel/fork.c:2153 kernel_clone+0x2d7/0x940 kernel/fork.c:2748 user_mode_thread+0x110/0x180 kernel/fork.c:2824 call_usermodehelper_exec_work+0x5c/0x230 kernel/umh.c:171 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x388/0x470 kernel/kthread.c:436 page_owner free stack trace missing Memory state around the buggy address: ffff8880290e6f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880290e6f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880290e7000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880290e7080: fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc ffff8880290e7100: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================