loop4: detected capacity change from 0 to 32768 ================================================================== BUG: KASAN: slab-use-after-free in ciCompare fs/jfs/jfs_dtree.c:3428 [inline] BUG: KASAN: slab-use-after-free in dtSearch+0x16b4/0x21b0 fs/jfs/jfs_dtree.c:645 Read of size 1 at addr ffff88806d7b4f5c by task syz.4.15639/25386 CPU: 0 UID: 0 PID: 25386 Comm: syz.4.15639 Not tainted 6.17.0-rc1-next-20250814-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 ciCompare fs/jfs/jfs_dtree.c:3428 [inline] dtSearch+0x16b4/0x21b0 fs/jfs/jfs_dtree.c:645 jfs_lookup+0x155/0x380 fs/jfs/namei.c:1461 __lookup_slow+0x294/0x3d0 fs/namei.c:1808 lookup_slow+0x53/0x70 fs/namei.c:1825 walk_component fs/namei.c:2129 [inline] link_path_walk+0x935/0xea0 fs/namei.c:2497 path_parentat fs/namei.c:2701 [inline] __filename_parentat+0x246/0x670 fs/namei.c:2725 filename_parentat fs/namei.c:2743 [inline] filename_create+0xd2/0x3c0 fs/namei.c:4120 do_mkdirat+0xa0/0x590 fs/namei.c:4391 __do_sys_mkdirat fs/namei.c:4416 [inline] __se_sys_mkdirat fs/namei.c:4414 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4414 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb9c518ebe9 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:00007fb9c601c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007fb9c53b5fa0 RCX: 00007fb9c518ebe9 RDX: 0000000000000000 RSI: 0000200000000640 RDI: ffffffffffffff9c RBP: 00007fb9c5211e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb9c53b6038 R14: 00007fb9c53b5fa0 R15: 00007ffc020de3c8 Allocated by task 23181: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_lru_noprof+0x1c6/0x3d0 mm/slub.c:4248 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105 alloc_inode+0x6a/0x1b0 fs/inode.c:346 new_inode+0x22/0x170 fs/inode.c:1145 diReadSpecial+0x52/0x710 fs/jfs/jfs_imap.c:426 jfs_mount+0x3d1/0x870 fs/jfs/jfs_mount.c:166 jfs_fill_super+0x6bc/0xd80 fs/jfs/super.c:523 get_tree_bdev_flags+0x40b/0x4d0 fs/super.c:1692 vfs_get_tree+0x8f/0x2b0 fs/super.c:1752 do_new_mount+0x2a2/0xa30 fs/namespace.c:3807 do_mount fs/namespace.c:4135 [inline] __do_sys_mount fs/namespace.c:4346 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4323 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 18567: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 __kasan_save_free_info+0x46/0x50 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+0x5b/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x18f/0x400 mm/slub.c:4782 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xca8/0x1770 kernel/rcu/tree.c:2861 handle_softirqs+0x286/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:559 __call_rcu_common kernel/rcu/tree.c:3123 [inline] call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3243 destroy_inode fs/inode.c:401 [inline] evict+0x847/0x9c0 fs/inode.c:834 jfs_umount+0x199/0x3c0 fs/jfs/jfs_umount.c:65 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x132/0x2c0 fs/super.c:643 kill_block_super+0x44/0x90 fs/super.c:1723 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1378 task_work_run+0x1d4/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x6b5/0x2300 kernel/exit.c:961 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102 __do_sys_exit_group kernel/exit.c:1113 [inline] __se_sys_exit_group kernel/exit.c:1111 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111 x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88806d7b49c0 which belongs to the cache jfs_ip of size 2232 The buggy address is located 1436 bytes inside of freed 2232-byte region [ffff88806d7b49c0, ffff88806d7b5278) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88806d7b1270 pfn:0x6d7b0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88805bec5301 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff8881422ffa00 dead000000000122 0000000000000000 raw: ffff88806d7b1270 00000000800d0006 00000000f5000000 ffff88805bec5301 head: 00fff00000000040 ffff8881422ffa00 dead000000000122 0000000000000000 head: ffff88806d7b1270 00000000800d0006 00000000f5000000 ffff88805bec5301 head: 00fff00000000003 ffffea0001b5ec01 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 15749, tgid 15748 (syz.7.3357), ts 512577782514, free_ts 498778564529 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:2487 [inline] allocate_slab+0x8a/0x370 mm/slub.c:2655 new_slab mm/slub.c:2709 [inline] ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891 __slab_alloc mm/slub.c:3981 [inline] __slab_alloc_node mm/slub.c:4056 [inline] slab_alloc_node mm/slub.c:4217 [inline] kmem_cache_alloc_lru_noprof+0x288/0x3d0 mm/slub.c:4248 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105 alloc_inode+0x6a/0x1b0 fs/inode.c:346 iget_locked+0xf0/0x570 fs/inode.c:1438 jfs_iget+0x24/0x3e0 fs/jfs/inode.c:29 jfs_lookup+0x1c5/0x380 fs/jfs/namei.c:1469 lookup_open fs/namei.c:3686 [inline] open_last_lookups fs/namei.c:3807 [inline] path_openat+0x10fe/0x3830 fs/namei.c:4043 do_filp_open+0x1fa/0x410 fs/namei.c:4073 do_sys_openat2+0x121/0x1c0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1461 page last free pid 15436 tgid 15436 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895 __slab_free+0x303/0x3c0 mm/slub.c:4591 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:349 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4180 [inline] slab_alloc_node mm/slub.c:4229 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4236 new_handle fs/jbd2/transaction.c:457 [inline] jbd2__journal_start+0x146/0x5b0 fs/jbd2/transaction.c:484 __ext4_journal_start_sb+0x227/0x5c0 fs/ext4/ext4_jbd2.c:115 __ext4_journal_start fs/ext4/ext4_jbd2.h:242 [inline] ext4_dirty_inode+0x93/0x110 fs/ext4/inode.c:6535 __mark_inode_dirty+0x2e9/0xe10 fs/fs-writeback.c:2527 generic_update_time fs/inode.c:2063 [inline] inode_update_time fs/inode.c:2076 [inline] __file_update_time fs/inode.c:2303 [inline] file_update_time+0x40c/0x490 fs/inode.c:2333 ext4_page_mkwrite+0x20e/0x1190 fs/ext4/inode.c:6704 do_page_mkwrite+0x14a/0x310 mm/memory.c:3489 do_shared_fault mm/memory.c:5777 [inline] do_fault mm/memory.c:5839 [inline] do_pte_missing mm/memory.c:4362 [inline] handle_pte_fault mm/memory.c:6180 [inline] __handle_mm_fault+0x1916/0x5440 mm/memory.c:6323 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6492 do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336 Memory state around the buggy address: ffff88806d7b4e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806d7b4e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88806d7b4f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806d7b4f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806d7b5000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb 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