bcachefs (loop1): hash table key at wrong offset: should be at 8607060773457356477 u64s 7 type dirent 4096:4330382808765833931:U32_MAX len 0 ver 0:  -> 536870912 type unknown, fixing ================================================================== BUG: KASAN: slab-use-after-free in bch2_str_hash_repair_key+0x2d42/0x3fa0 fs/bcachefs/str_hash.c:335 Read of size 8 at addr ffff8880786b1328 by task syz.1.2281/16687 CPU: 1 UID: 0 PID: 16687 Comm: syz.1.2281 Not tainted 6.16.0-rc1-next-20250610-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xd2/0x2b0 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 bch2_str_hash_repair_key+0x2d42/0x3fa0 fs/bcachefs/str_hash.c:335 __bch2_str_hash_check_key+0xa65/0xd40 fs/bcachefs/str_hash.c:394 bch2_str_hash_check_key fs/bcachefs/str_hash.h:429 [inline] bch2_readdir+0x11cd/0x16f0 fs/bcachefs/dirent.c:685 bch2_vfs_readdir+0x4d0/0x6c0 fs/bcachefs/fs.c:1581 iterate_dir+0x5ac/0x770 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:410 [inline] __se_sys_getdents64+0xe4/0x260 fs/readdir.c:396 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: 0033:0x7fc4d058e929 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:00007fc4d14cb038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007fc4d07b5fa0 RCX: 00007fc4d058e929 RDX: 0000000000001000 RSI: 0000200000000f80 RDI: 0000000000000004 RBP: 00007fc4d0610b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc4d07b5fa0 R15: 00007ffef933ddf8 Allocated by task 16687: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4328 [inline] __kmalloc_node_track_caller_noprof+0x271/0x4e0 mm/slub.c:4347 __do_krealloc mm/slub.c:4905 [inline] krealloc_noprof+0x124/0x340 mm/slub.c:4958 __bch2_trans_kmalloc+0x26c/0xc80 fs/bcachefs/btree_iter.c:3187 bch2_trans_kmalloc_ip fs/bcachefs/btree_iter.h:604 [inline] bch2_trans_kmalloc fs/bcachefs/btree_iter.h:616 [inline] bch2_str_hash_repair_key+0x2a65/0x3fa0 fs/bcachefs/str_hash.c:251 __bch2_str_hash_check_key+0xa65/0xd40 fs/bcachefs/str_hash.c:394 bch2_str_hash_check_key fs/bcachefs/str_hash.h:429 [inline] bch2_readdir+0x11cd/0x16f0 fs/bcachefs/dirent.c:685 bch2_vfs_readdir+0x4d0/0x6c0 fs/bcachefs/fs.c:1581 iterate_dir+0x5ac/0x770 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:410 [inline] __se_sys_getdents64+0xe4/0x260 fs/readdir.c:396 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 16687: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x18e/0x440 mm/slub.c:4842 krealloc_noprof+0x1cd/0x340 mm/slub.c:-1 __bch2_trans_kmalloc+0x26c/0xc80 fs/bcachefs/btree_iter.c:3187 bch2_trans_kmalloc_ip fs/bcachefs/btree_iter.h:604 [inline] bch2_trans_kmalloc fs/bcachefs/btree_iter.h:616 [inline] bch2_hash_delete_at fs/bcachefs/str_hash.h:364 [inline] bch2_str_hash_repair_key+0x2fde/0x3fa0 fs/bcachefs/str_hash.c:289 __bch2_str_hash_check_key+0xa65/0xd40 fs/bcachefs/str_hash.c:394 bch2_str_hash_check_key fs/bcachefs/str_hash.h:429 [inline] bch2_readdir+0x11cd/0x16f0 fs/bcachefs/dirent.c:685 bch2_vfs_readdir+0x4d0/0x6c0 fs/bcachefs/fs.c:1581 iterate_dir+0x5ac/0x770 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:410 [inline] __se_sys_getdents64+0xe4/0x260 fs/readdir.c:396 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 ffff8880786b1300 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 40 bytes inside of freed 128-byte region [ffff8880786b1300, ffff8880786b1380) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x786b1 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801a441a00 ffffea0000c712c0 dead000000000004 raw: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 6194, tgid 6194 (udevd), ts 156116340189, free_ts 156022836563 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419 alloc_slab_page mm/slub.c:2451 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2619 new_slab mm/slub.c:2673 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3859 __slab_alloc mm/slub.c:3949 [inline] __slab_alloc_node mm/slub.c:4024 [inline] slab_alloc_node mm/slub.c:4185 [inline] __kmalloc_cache_noprof+0x296/0x3d0 mm/slub.c:4354 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] kernfs_get_open_node fs/kernfs/file.c:525 [inline] kernfs_fop_open+0x7b5/0xca0 fs/kernfs/file.c:700 do_dentry_open+0xdf3/0x1970 fs/open.c:964 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:3887 [inline] path_openat+0x2ee5/0x3830 fs/namei.c:4046 do_filp_open+0x1fa/0x410 fs/namei.c:4073 do_sys_openat2+0x121/0x1c0 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+0x138/0x170 fs/open.c:1463 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 page last free pid 6048 tgid 6048 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706 pagetable_free include/linux/mm.h:2885 [inline] pagetable_dtor_free include/linux/mm.h:2983 [inline] __tlb_remove_table+0x2d2/0x3b0 include/asm-generic/tlb.h:220 __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x85/0x100 mm/mmu_gather.c:290 rcu_do_batch kernel/rcu/tree.c:2576 [inline] rcu_core+0xca5/0x1710 kernel/rcu/tree.c:2832 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 Memory state around the buggy address: ffff8880786b1200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880786b1280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880786b1300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880786b1380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880786b1400: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc ==================================================================