svc: failed to register nfsdv3 RPC service (errno 111). svc: failed to register nfsaclv3 RPC service (errno 111). ================================================================== BUG: KASAN: use-after-free in nfsd_svc+0x996/0xab0 fs/nfsd/nfssvc.c:813 Read of size 4 at addr ffff888055f41454 by task syz.4.661/7205 CPU: 0 PID: 7205 Comm: syz.4.661 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 nfsd_svc+0x996/0xab0 fs/nfsd/nfssvc.c:813 write_threads+0x2ea/0x350 fs/nfsd/nfsctl.c:424 nfsctl_transaction_write+0x105/0x150 fs/nfsd/nfsctl.c:114 vfs_write+0x2dc/0x9a0 fs/read_write.c:582 ksys_write+0x14d/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f560919e159 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f560a083028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f5609425fa0 RCX: 00007f560919e159 RDX: 0000000000000002 RSI: 0000200000000240 RDI: 0000000000000003 RBP: 00007f560923503b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5609426038 R14: 00007f5609425fa0 R15: 00007ffeeb4ce158 Allocated by task 7205: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] __svc_create+0x60/0x9d0 net/sunrpc/svc.c:491 svc_create_pooled+0x71f/0x8c0 net/sunrpc/svc.c:579 nfsd_create_serv+0x2f9/0x700 fs/nfsd/nfssvc.c:667 nfsd_svc+0x17f/0xab0 fs/nfsd/nfssvc.c:796 write_threads+0x2ea/0x350 fs/nfsd/nfsctl.c:424 nfsctl_transaction_write+0x105/0x150 fs/nfsd/nfsctl.c:114 vfs_write+0x2dc/0x9a0 fs/read_write.c:582 ksys_write+0x14d/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 7205: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0x133/0x1b0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] __kmem_cache_free+0xb6/0x200 mm/slub.c:3700 kref_put include/linux/kref.h:65 [inline] svc_put include/linux/sunrpc/svc.h:123 [inline] nfsd_svc+0x75e/0xab0 fs/nfsd/nfssvc.c:811 write_threads+0x2ea/0x350 fs/nfsd/nfsctl.c:424 nfsctl_transaction_write+0x105/0x150 fs/nfsd/nfsctl.c:114 vfs_write+0x2dc/0x9a0 fs/read_write.c:582 ksys_write+0x14d/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 insert_work+0x54/0x3c0 kernel/workqueue.c:1361 __queue_work+0xae2/0xee0 kernel/workqueue.c:1520 call_timer_fn+0x1ac/0x670 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1747 [inline] __run_timers+0x598/0x810 kernel/time/timer.c:2023 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2036 handle_softirqs+0x291/0x910 kernel/softirq.c:596 __do_softirq kernel/softirq.c:630 [inline] invoke_softirq kernel/softirq.c:470 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 The buggy address belongs to the object at ffff888055f41400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 84 bytes inside of 512-byte region [ffff888055f41400, ffff888055f41600) The buggy address belongs to the physical page: page:ffffea000157d000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x55f40 head:ffffea000157d000 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888017441c80 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4274, tgid 4274 (syz-executor), ts 82652411512, free_ts 25048505668 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2560 prep_new_page mm/page_alloc.c:2567 [inline] get_page_from_freelist+0x206b/0x2180 mm/page_alloc.c:4358 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5658 alloc_slab_page+0x5d/0x180 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2d0 mm/slub.c:1997 ___slab_alloc+0xbc5/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x126/0x270 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc_node_track_caller+0xa0/0x240 mm/slab_common.c:956 kmalloc_reserve net/core/skbuff.c:446 [inline] __alloc_skb+0x226/0x7d0 net/core/skbuff.c:515 alloc_skb include/linux/skbuff.h:1303 [inline] nlmsg_new include/net/netlink.h:998 [inline] netlink_ack+0x373/0x1160 net/netlink/af_netlink.c:2453 netlink_rcv_skb+0x26d/0x440 net/netlink/af_netlink.c:2522 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x7ad/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ad/0xbd0 net/netlink/af_netlink.c:1877 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] __sys_sendto+0x497/0x650 net/socket.c:2153 __do_sys_sendto net/socket.c:2165 [inline] __se_sys_sendto net/socket.c:2161 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2161 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1487 [inline] free_pcp_prepare mm/page_alloc.c:1537 [inline] free_unref_page_prepare+0x8e5/0x9e0 mm/page_alloc.c:3414 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3509 free_contig_range+0x9d/0x150 mm/page_alloc.c:9498 destroy_args+0xef/0xa0e mm/debug_vm_pgtable.c:1031 debug_vm_pgtable+0x33c/0x38e mm/debug_vm_pgtable.c:1359 do_one_initcall+0x257/0x800 init/main.c:1270 do_initcall_level+0x13d/0x1ed init/main.c:1343 do_initcalls+0x4b/0x8a init/main.c:1359 kernel_init_freeable+0x401/0x5ab init/main.c:1598 kernel_init+0x19/0x1b0 init/main.c:1486 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff888055f41300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888055f41380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888055f41400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888055f41480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888055f41500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================