================================================================== BUG: KASAN: slab-out-of-bounds in bch2_dirent_init_name+0x396/0x8b0 fs/bcachefs/dirent.c:276 Write of size 1985 at addr ffff88803c91a22b by task syz.2.194/7293 CPU: 1 UID: 0 PID: 7293 Comm: syz.2.194 Tainted: G W 6.16.0-syzkaller-01056-gae388edd4a8f #0 PREEMPT_{RT,(full)} Tainted: [W]=WARN 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 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:189 __asan_memset+0x22/0x50 mm/kasan/shadow.c:84 bch2_dirent_init_name+0x396/0x8b0 fs/bcachefs/dirent.c:276 bch2_dirent_create_key+0x2a1/0x5f0 fs/bcachefs/dirent.c:319 bch2_dirent_create+0xc5/0xc80 fs/bcachefs/dirent.c:362 bch2_link_trans+0x39e/0x560 fs/bcachefs/namei.c:241 __bch2_link+0x231/0x3f0 fs/bcachefs/fs.c:776 bch2_symlink+0x183/0x240 fs/bcachefs/fs.c:892 vfs_symlink+0x143/0x2f0 fs/namei.c:4730 do_symlinkat+0x1b1/0x3f0 fs/namei.c:4756 __do_sys_symlink fs/namei.c:4777 [inline] __se_sys_symlink fs/namei.c:4775 [inline] __x64_sys_symlink+0x7a/0x90 fs/namei.c:4775 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: 0033:0x7ff7a60ae9a9 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:00007ff7a3f0e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 00007ff7a62d5fa0 RCX: 00007ff7a60ae9a9 RDX: 0000000000000000 RSI: 00002000000009c0 RDI: 0000200000000280 RBP: 00007ff7a6130d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff7a62d5fa0 R15: 00007ffd543bd328 Allocated by task 7293: 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_noprof+0x1ef/0x430 mm/slub.c:4340 kmalloc_noprof include/linux/slab.h:909 [inline] __bch2_trans_kmalloc+0x395/0x9d0 fs/bcachefs/btree_iter.c:3242 bch2_trans_kmalloc_ip fs/bcachefs/btree_iter.h:604 [inline] bch2_trans_kmalloc fs/bcachefs/btree_iter.h:616 [inline] bch2_dirent_create_key+0x113/0x5f0 fs/bcachefs/dirent.c:302 bch2_dirent_create+0xc5/0xc80 fs/bcachefs/dirent.c:362 bch2_link_trans+0x39e/0x560 fs/bcachefs/namei.c:241 __bch2_link+0x231/0x3f0 fs/bcachefs/fs.c:776 bch2_symlink+0x183/0x240 fs/bcachefs/fs.c:892 vfs_symlink+0x143/0x2f0 fs/namei.c:4730 do_symlinkat+0x1b1/0x3f0 fs/namei.c:4756 __do_sys_symlink fs/namei.c:4777 [inline] __se_sys_symlink fs/namei.c:4775 [inline] __x64_sys_symlink+0x7a/0x90 fs/namei.c:4775 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 ffff88803c91a000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 555 bytes inside of allocated 2048-byte region [ffff88803c91a000, ffff88803c91a800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3c918 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff888019842000 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000 head: 0080000000000040 ffff888019842000 dead000000000100 dead000000000122 head: 0000000000000000 0000000080080008 00000000f5000000 0000000000000000 head: 0080000000000003 ffffea0000f24601 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 9, tgid 9 (kworker/0:0), ts 101581921922, free_ts 100935275752 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+0x2119/0x21b0 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959 alloc_pages_mpol+0xd1/0x380 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+0x8e7/0xe20 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+0xe6/0x320 mm/slub.c:4354 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] keypair_create drivers/net/wireguard/noise.c:100 [inline] wg_noise_handshake_begin_session+0xcc/0xbe0 drivers/net/wireguard/noise.c:827 wg_receive_handshake_packet drivers/net/wireguard/receive.c:176 [inline] wg_packet_handshake_receive_worker+0x707/0xfa0 drivers/net/wireguard/receive.c:213 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 page last free pid 5815 tgid 5815 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xbe5/0xdf0 mm/page_alloc.c:2706 discard_slab mm/slub.c:2717 [inline] __put_partials+0x168/0x1c0 mm/slub.c:3186 __slab_free+0x2c0/0x3b0 mm/slub.c:4513 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:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_noprof+0x143/0x310 mm/slub.c:4204 fib_table_insert+0x4a7/0x1b50 net/ipv4/fib_trie.c:1338 fib_magic+0x2c4/0x390 net/ipv4/fib_frontend.c:1133 fib_add_ifaddr+0x144/0x5f0 net/ipv4/fib_frontend.c:1155 fib_inetaddr_event+0x12e/0x190 net/ipv4/fib_frontend.c:1469 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 blocking_notifier_call_chain+0x6a/0x90 kernel/notifier.c:380 __inet_insert_ifa+0xa13/0xbf0 net/ipv4/devinet.c:567 inet_rtm_newaddr+0xf3a/0x18b0 net/ipv4/devinet.c:1002 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6944 Memory state around the buggy address: ffff88803c91a700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88803c91a780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88803c91a800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88803c91a880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88803c91a900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================