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 ffff88807e511854 by task syz.4.20/4417 CPU: 1 PID: 4417 Comm: syz.4.20 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: 0033:0x7f649b99e019 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:00007f649c795028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f649bc25fa0 RCX: 00007f649b99e019 RDX: 0000000000000002 RSI: 00002000000001c0 RDI: 0000000000000004 RBP: 00007f649ba3500c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f649bc26038 R14: 00007f649bc25fa0 R15: 00007ffe224c93d8 Allocated by task 4417: 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:464 svc_create_pooled+0x71f/0x8c0 net/sunrpc/svc.c:552 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 4417: 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 The buggy address belongs to the object at ffff88807e511800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 84 bytes inside of 512-byte region [ffff88807e511800, ffff88807e511a00) The buggy address belongs to the physical page: page:ffffea0001f94400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7e510 head:ffffea0001f94400 order:2 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4376, tgid 4376 (udevd), ts 90712265603, free_ts 80410688979 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 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] kernfs_fop_open+0x3ce/0xc60 fs/kernfs/file.c:690 do_dentry_open+0x7dd/0x10b0 fs/open.c:882 do_open fs/namei.c:3634 [inline] path_openat+0x2674/0x2f10 fs/namei.c:3791 do_filp_open+0x1ee/0x420 fs/namei.c:3818 do_sys_openat2+0x14b/0x4f0 fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1347 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 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 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x490 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] __kmem_cache_alloc_node+0x19d/0x270 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc+0xa3/0x240 mm/slab_common.c:949 kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:699 [inline] kobject_get_path+0xac/0x220 lib/kobject.c:152 kobject_uevent_env+0x28d/0x890 lib/kobject_uevent.c:544 rx_queue_add_kobject net/core/net-sysfs.c:1072 [inline] net_rx_queue_update_kobjects+0x244/0x4d0 net/core/net-sysfs.c:1112 register_queue_kobjects net/core/net-sysfs.c:1772 [inline] netdev_register_kobject+0x231/0x320 net/core/net-sysfs.c:2017 register_netdevice+0x133a/0x1b80 net/core/dev.c:10243 vxcan_newlink+0x42c/0x670 drivers/net/can/vxcan.c:224 rtnl_newlink_create net/core/rtnetlink.c:3436 [inline] __rtnl_newlink net/core/rtnetlink.c:3656 [inline] rtnl_newlink+0x14b3/0x1f90 net/core/rtnetlink.c:3669 rtnetlink_rcv_msg+0x863/0xfb0 net/core/rtnetlink.c:6166 Memory state around the buggy address: ffff88807e511700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807e511780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807e511800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807e511880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e511900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================