TITLE: BUG: unable to handle kernel paging request in nfsd_reply_cache_free_locked
ALT: bad-access in nfsd_reply_cache_free_locked
TYPE: MEMORY_SAFETY_BUG

[ 1261.886878][ T8682] BUG: unable to handle page fault for address: ffff887ffffffff0
[ 1261.894638][ T8682] #PF: supervisor read access in kernel mode
[ 1261.900641][ T8682] #PF: error_code(0x0000) - not-present page
[ 1261.906619][ T8682] PGD 0 P4D 0 
[ 1261.910023][ T8682] Oops: 0000 [#1] PREEMPT SMP KASAN
[ 1261.915219][ T8682] CPU: 1 PID: 8682 Comm: syz-executor.3 Not tainted 5.7.0-rc5-syzkaller #0
[ 1261.924432][ T8682] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 1261.934612][ T8682] RIP: 0010:rb_erase+0x37/0x18d0
[ 1261.939554][ T8682] Code: 89 f7 41 56 41 55 49 89 fd 48 83 c7 08 48 89 fa 41 54 48 c1 ea 03 55 53 48 83 ec 18 80 3c 02 00 0f 85 89 10 00 00 49 8d 7d 10 <4d> 8b 75 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80
[ 1261.959271][ T8682] RSP: 0018:ffffc900178ffb58 EFLAGS: 00010246
[ 1261.965338][ T8682] RAX: dffffc0000000000 RBX: ffff8880354d0000 RCX: ffffc9000fb6d000
[ 1261.973306][ T8682] RDX: 1ffff10ffffffffe RSI: ffff88800011dfe0 RDI: ffff887ffffffff8
[ 1261.981275][ T8682] RBP: ffff887fffffffb0 R08: ffff888057284280 R09: fffffbfff185d12e
[ 1261.989539][ T8682] R10: ffffffff8c2e896f R11: fffffbfff185d12d R12: ffff88800011dfe0
[ 1261.997507][ T8682] R13: ffff887fffffffe8 R14: 000000000001dfe0 R15: ffff88800011dfe0
[ 1262.005477][ T8682] FS:  00007fa002d21700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
[ 1262.014487][ T8682] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1262.021065][ T8682] CR2: ffff887ffffffff0 CR3: 00000000a2164000 CR4: 00000000001426e0
[ 1262.029036][ T8682] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1262.037003][ T8682] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1262.044970][ T8682] Call Trace:
[ 1262.053686][ T8682]  nfsd_reply_cache_free_locked+0x198/0x380
[ 1262.059588][ T8682]  nfsd_reply_cache_shutdown+0x150/0x350
[ 1262.065276][ T8682]  nfsd_exit_net+0x189/0x4c0
[ 1262.075053][ T8682]  ops_exit_list.isra.0+0xa8/0x150
[ 1262.080169][ T8682]  setup_net+0x50c/0x860
[ 1262.088742][ T8682]  copy_net_ns+0x293/0x590
[ 1262.093348][ T8682]  create_new_namespaces+0x3fb/0xb30
[ 1262.098638][ T8682]  unshare_nsproxy_namespaces+0xbd/0x1f0
[ 1262.104341][ T8682]  ksys_unshare+0x43d/0x8e0
[ 1262.131145][ T8682]  __x64_sys_unshare+0x2d/0x40
[ 1262.136080][ T8682]  do_syscall_64+0xf6/0x7d0
[ 1262.140653][ T8682]  entry_SYSCALL_64_after_hwframe+0x49/0xb3
[ 1262.146545][ T8682] RIP: 0033:0x45ca29
[ 1262.150436][ T8682] Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
[ 1262.170036][ T8682] RSP: 002b:00007fa002d20c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
[ 1262.178479][ T8682] RAX: ffffffffffffffda RBX: 000000000050a1c0 RCX: 000000000045ca29
[ 1262.186452][ T8682] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
[ 1262.194428][ T8682] RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
[ 1262.202401][ T8682] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
[ 1262.210374][ T8682] R13: 0000000000000c4e R14: 00000000004ce9bd R15: 00007fa002d216d4
[ 1262.218377][ T8682] Modules linked in:
[ 1262.222267][ T8682] CR2: ffff887ffffffff0
[ 1262.226422][ T8682] ---[ end trace f929dcba0362906a ]---
