svc: failed to register nfsdv3 RPC service (errno 111). svc: failed to register nfsaclv3 RPC service (errno 111). ================================================================== BUG: KASAN: slab-use-after-free in nfsd_svc+0x99a/0xab0 fs/nfsd/nfssvc.c:818 Read of size 4 at addr ffff88805cdfcc54 by task syz.0.134/6146 CPU: 0 PID: 6146 Comm: syz.0.134 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 nfsd_svc+0x99a/0xab0 fs/nfsd/nfssvc.c:818 write_threads+0x393/0x510 fs/nfsd/nfsctl.c:417 nfsctl_transaction_write+0x10c/0x150 fs/nfsd/nfsctl.c:113 vfs_write+0x299/0x9a0 fs/read_write.c:582 ksys_write+0x151/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fbcee39e199 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:00007fbcef2c9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fbcee625fa0 RCX: 00007fbcee39e199 RDX: 0000000000000001 RSI: 0000200000000440 RDI: 0000000000000003 RBP: 00007fbcee4358e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fbcee626038 R14: 00007fbcee625fa0 R15: 00007ffe7525d0a8 Allocated by task 6146: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] __svc_create+0x60/0xbb0 net/sunrpc/svc.c:520 svc_create_pooled+0x66a/0x7e0 net/sunrpc/svc.c:618 nfsd_create_serv+0x29f/0x5c0 fs/nfsd/nfssvc.c:672 nfsd_svc+0x183/0xab0 fs/nfsd/nfssvc.c:801 write_threads+0x393/0x510 fs/nfsd/nfsctl.c:417 nfsctl_transaction_write+0x10c/0x150 fs/nfsd/nfsctl.c:113 vfs_write+0x299/0x9a0 fs/read_write.c:582 ksys_write+0x151/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 6146: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3843 kref_put include/linux/kref.h:65 [inline] svc_put include/linux/sunrpc/svc.h:124 [inline] nfsd_svc+0x762/0xab0 fs/nfsd/nfssvc.c:816 write_threads+0x393/0x510 fs/nfsd/nfsctl.c:417 nfsctl_transaction_write+0x10c/0x150 fs/nfsd/nfsctl.c:113 vfs_write+0x299/0x9a0 fs/read_write.c:582 ksys_write+0x151/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x153/0x900 kernel/rcu/tree.c:2837 fib6_info_release include/net/ip6_fib.h:349 [inline] ip6_route_info_create+0xa0d/0x1260 net/ipv6/route.c:3891 ip6_route_add+0x28/0x160 net/ipv6/route.c:3905 addrconf_add_mroute net/ipv6/addrconf.c:2534 [inline] addrconf_add_dev+0x29c/0x3b0 net/ipv6/addrconf.c:2552 inet6_addr_add+0x25d/0xb30 net/ipv6/addrconf.c:3032 inet6_rtm_newaddr+0x6fd/0x9d0 net/ipv6/addrconf.c:5050 rtnetlink_rcv_msg+0x843/0xf90 net/core/rtnetlink.c:6484 netlink_rcv_skb+0x235/0x4c0 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x7b1/0x930 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1899 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x4a9/0x6b0 net/socket.c:2201 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88805cdfcc00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 84 bytes inside of freed 512-byte region [ffff88805cdfcc00, ffff88805cdfce00) The buggy address belongs to the physical page: page:ffffea0001737f00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805cdff800 pfn:0x5cdfc head:ffffea0001737f00 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017c41c80 ffffea000093c700 0000000000000002 raw: ffff88805cdff800 000000008010000e 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5779, tgid 5779 (syz-executor), ts 87697264036, free_ts 87679902589 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1582 prep_new_page mm/page_alloc.c:1589 [inline] get_page_from_freelist+0x2181/0x22a0 mm/page_alloc.c:3221 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4501 alloc_slab_page+0x5d/0x180 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5c/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x11f/0x250 mm/slub.c:3534 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] devcgroup_css_alloc+0x4e/0x100 security/device_cgroup.c:226 css_create kernel/cgroup/cgroup.c:5561 [inline] cgroup_apply_control_enable+0x3cc/0xb00 kernel/cgroup/cgroup.c:3219 cgroup_mkdir+0xc83/0xe70 kernel/cgroup/cgroup.c:5779 kernfs_iop_mkdir+0x241/0x3e0 fs/kernfs/dir.c:1246 vfs_mkdir+0x2a5/0x470 fs/namei.c:4168 do_mkdirat+0x1dc/0x450 fs/namei.c:4191 __do_sys_mkdirat fs/namei.c:4206 [inline] __se_sys_mkdirat fs/namei.c:4204 [inline] __x64_sys_mkdirat+0x89/0xa0 fs/namei.c:4204 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 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:1182 [inline] free_unref_page_prepare+0x7d7/0x8f0 mm/page_alloc.c:2366 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2459 __stack_depot_save+0x587/0x660 lib/stackdepot.c:443 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_set_track+0x5f/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] kmem_cache_free+0xf8/0x290 mm/slub.c:3852 rcu_do_batch kernel/rcu/tree.c:2194 [inline] rcu_core+0x9c1/0x17f0 kernel/rcu/tree.c:2467 handle_softirqs+0x27d/0x820 kernel/softirq.c:578 do_softirq+0xfa/0x1a0 kernel/softirq.c:479 __local_bh_enable_ip+0x184/0x1c0 kernel/softirq.c:406 addrconf_dad_completed+0xa51/0xd90 net/ipv6/addrconf.c:4371 addrconf_dad_work+0xc9e/0x1550 net/ipv6/addrconf.c:-1 process_one_work kernel/workqueue.c:2657 [inline] process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815 Memory state around the buggy address: ffff88805cdfcb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805cdfcb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805cdfcc00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805cdfcc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805cdfcd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================