Description: null pointer dereference in nfs4_preprocess_stateid_op()
References:
 https://bugzilla.redhat.com/show_bug.cgi?id=1655162
Notes:
 bwh> Introduced in 4.5 by commit ffa0160a1039 "nfsd: implement the NFSv4.2
 bwh> CLONE operation".
Bugs:
upstream: released (4.20-rc3) [01310bb7c9c98752cc763b36532fab028e0f8f81]
4.19-upstream-stable: released (4.19.3) [20965de7f47207394ffe03d70a4806f5e1cfcd7f]
4.9-upstream-stable: released (4.9.136) [7291d95a97fc89044301b197c760555e894e82c7]
3.16-upstream-stable: N/A "Vulnerable code not present"
sid: released (4.18.20-1)
4.9-stretch-security: released (4.9.144-1)
3.16-jessie-security: N/A "Vulnerable code not present"