================================================================== BUG: KASAN: slab-use-after-free in dtSplitPage+0x38cd/0x39e0 fs/jfs/jfs_dtree.c:1522 Read of size 1 at addr ffff88808bfa8935 by task syz.2.7728/31056 CPU: 1 UID: 0 PID: 31056 Comm: syz.2.7728 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 dtSplitPage+0x38cd/0x39e0 fs/jfs/jfs_dtree.c:1522 dtSplitUp+0x7ba/0x5970 fs/jfs/jfs_dtree.c:1092 dtInsert+0x8dd/0xb60 fs/jfs/jfs_dtree.c:871 jfs_mkdir+0x67d/0xba0 fs/jfs/namei.c:270 vfs_mkdir+0x593/0x8c0 fs/namei.c:4453 do_mkdirat+0x304/0x3e0 fs/namei.c:4486 __do_sys_mkdirat fs/namei.c:4503 [inline] __se_sys_mkdirat fs/namei.c:4501 [inline] __x64_sys_mkdirat+0x83/0xb0 fs/namei.c:4501 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa0b798eec9 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:00007fa0b875d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007fa0b7be5fa0 RCX: 00007fa0b798eec9 RDX: 0000000000000000 RSI: 0000200000000040 RDI: ffffffffffffff9c RBP: 00007fa0b7a11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa0b7be6038 R14: 00007fa0b7be5fa0 R15: 00007ffddb9ba0f8 Allocated by task 30078: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:342 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:368 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4955 [inline] slab_alloc_node mm/slub.c:5265 [inline] kmem_cache_alloc_lru_noprof+0x254/0x6e0 mm/slub.c:5284 jfs_alloc_inode+0x25/0x60 fs/jfs/super.c:105 alloc_inode+0x64/0x240 fs/inode.c:346 iget_locked+0x2fa/0x860 fs/inode.c:1445 jfs_iget+0x20/0x590 fs/jfs/inode.c:29 jfs_lookup+0x2b2/0x380 fs/jfs/namei.c:1469 lookup_open.isra.0+0x4da/0x1580 fs/namei.c:3774 open_last_lookups fs/namei.c:3895 [inline] path_openat+0x893/0x2cb0 fs/namei.c:4131 do_filp_open+0x20b/0x470 fs/namei.c:4161 do_sys_openat2+0x11b/0x1d0 fs/open.c:1437 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1463 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 26825: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 __kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2523 [inline] slab_free mm/slub.c:6611 [inline] kmem_cache_free+0x2d4/0x6c0 mm/slub.c:6721 i_callback+0x46/0x70 fs/inode.c:325 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0x79c/0x1530 kernel/rcu/tree.c:2861 handle_softirqs+0x219/0x8e0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 Last potentially related work creation: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:559 __call_rcu_common.constprop.0+0xa5/0xa10 kernel/rcu/tree.c:3123 destroy_inode+0x12c/0x1b0 fs/inode.c:401 evict+0x5b4/0x920 fs/inode.c:834 iput_final fs/inode.c:1914 [inline] iput.part.0+0x6a9/0xb00 fs/inode.c:1966 iput+0x35/0x40 fs/inode.c:1929 txUpdateMap+0x995/0xb70 fs/jfs/jfs_txnmgr.c:2368 txLazyCommit fs/jfs/jfs_txnmgr.c:2665 [inline] jfs_lazycommit+0x5f9/0xb30 fs/jfs/jfs_txnmgr.c:2734 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x675/0x7d0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff88808bfa8928 which belongs to the cache jfs_ip of size 2216 The buggy address is located 13 bytes inside of freed 2216-byte region [ffff88808bfa8928, ffff88808bfa91d0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88808bfaede0 pfn:0x8bfa8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88806aafd701 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff8881472a9000 dead000000000122 0000000000000000 raw: ffff88808bfaede0 00000000800d000b 00000000f5000000 ffff88806aafd701 head: 00fff00000000040 ffff8881472a9000 dead000000000122 0000000000000000 head: ffff88808bfaede0 00000000800d000b 00000000f5000000 ffff88806aafd701 head: 00fff00000000003 ffffea00022fea01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Reclaimable, gfp_mask 0xd2050(__GFP_RECLAIMABLE|__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 28566, tgid 28565 (syz.6.7111), ts 1525202849629, free_ts 244750529695 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x10a3/0x3a30 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x25f/0x2470 mm/page_alloc.c:5183 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3039 [inline] allocate_slab mm/slub.c:3212 [inline] new_slab+0x24a/0x360 mm/slub.c:3266 ___slab_alloc+0xdc4/0x1ae0 mm/slub.c:4636 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4755 __slab_alloc_node mm/slub.c:4831 [inline] slab_alloc_node mm/slub.c:5253 [inline] kmem_cache_alloc_lru_noprof+0x443/0x6e0 mm/slub.c:5284 jfs_alloc_inode+0x25/0x60 fs/jfs/super.c:105 alloc_inode+0x64/0x240 fs/inode.c:346 new_inode+0x22/0x1c0 fs/inode.c:1145 ialloc+0x46/0x9e0 fs/jfs/jfs_inode.c:48 jfs_mkdir+0x24b/0xba0 fs/jfs/namei.c:225 vfs_mkdir+0x593/0x8c0 fs/namei.c:4453 do_mkdirat+0x304/0x3e0 fs/namei.c:4486 __do_sys_mkdirat fs/namei.c:4503 [inline] __se_sys_mkdirat fs/namei.c:4501 [inline] __x64_sys_mkdirat+0x83/0xb0 fs/namei.c:4501 page last free pid 5824 tgid 5824 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_pages_ok+0x725/0xf80 mm/page_alloc.c:1570 zstd_free_workspace fs/btrfs/zstd.c:366 [inline] zstd_free_workspace_manager+0x289/0x4b0 fs/btrfs/zstd.c:226 btrfs_free_fs_info+0x5f/0x4b0 fs/btrfs/disk-io.c:1250 deactivate_locked_super+0xc1/0x1a0 fs/super.c:473 deactivate_super fs/super.c:506 [inline] deactivate_super+0xde/0x100 fs/super.c:502 cleanup_mnt+0x225/0x450 fs/namespace.c:1327 task_work_run+0x150/0x240 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x130 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x426/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88808bfa8800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88808bfa8880: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc >ffff88808bfa8900: fc fc fc fc fc fa fb fb fb fb fb fb fb fb fb fb ^ ffff88808bfa8980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88808bfa8a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== read_mapping_page failed! ERROR: (device loop2): txAbort: