NFSD: Fix nfs4_verifier memory alignment

Clean up due to code review.

The nfs4_verifier's data field is not guaranteed to be u32-aligned.
Casting an array of chars to a u32 * is considered generally
hazardous.

We can fix most of this by using a __be32 array to generate the
verifier's contents and then byte-copying it into the verifier field.

However, there is one spot where there is a backwards compatibility
constraint: the do_nfsd_create() call expects a verifier which is
32-bit aligned.  Fix this spot by forcing the alignment of the create
verifier in the nfsd4_open args structure.

Also, sizeof(nfs4_verifer) is the size of the in-core verifier data
structure, but NFS4_VERIFIER_SIZE is the number of octets in an XDR'd
verifier.  The two are not interchangeable, even if they happen to
have the same value.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index cdc406a..e318964 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1174,12 +1174,12 @@ static void gen_clid(struct nfs4_client *clp)
 
 static void gen_confirm(struct nfs4_client *clp)
 {
+	__be32 verf[2];
 	static u32 i;
-	u32 *p;
 
-	p = (u32 *)clp->cl_confirm.data;
-	*p++ = get_seconds();
-	*p++ = i++;
+	verf[0] = (__be32)get_seconds();
+	verf[1] = (__be32)i++;
+	memcpy(clp->cl_confirm.data, verf, sizeof(clp->cl_confirm.data));
 }
 
 static struct nfs4_stid *find_stateid(struct nfs4_client *cl, stateid_t *t)