Ensure that OPDESC() doesn't return a pointer that doesn't lie within the array. In particular, this is a problem when this funtion is passed OP_ILLEGAL, but let's return NULL for any invalid value. Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> --- fs/nfsd/nfs4proc.c | 2 ++ 1 file changed, 2 insertions(+) This is the patch that I think we want ahead of this one: nfsd: call op_release, even when op_func returns an error If you end up with OP_ILLEGAL, then op->opdesc ends up pointing somewhere far, far away, and the new op_release changes can trip over that. We could add a Fixes tag for this, I suppose: 22b03214962e nfsd4: introduce OPDESC helper ...but that commit is from 2011, so it's probably not worth it. diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index 5ae670807449..5e7b4ca7a266 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -2494,6 +2494,8 @@ static __be32 nfs41_check_op_ordering(struct nfsd4_compoundargs *args) const struct nfsd4_operation *OPDESC(struct nfsd4_op *op) { + if (op->opnum < FIRST_NFS4_OP || op->opnum > LAST_NFS42_OP) + return NULL; return &nfsd4_ops[op->opnum]; } -- 2.39.2