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>
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 3f7dbc4..2a90366 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -489,14 +489,20 @@
&access->ac_supported);
}
+static void gen_boot_verifier(nfs4_verifier *verifier)
+{
+ __be32 verf[2];
+
+ verf[0] = (__be32)nfssvc_boot.tv_sec;
+ verf[1] = (__be32)nfssvc_boot.tv_usec;
+ memcpy(verifier->data, verf, sizeof(verifier->data));
+}
+
static __be32
nfsd4_commit(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
struct nfsd4_commit *commit)
{
- u32 *p = (u32 *)commit->co_verf.data;
- *p++ = nfssvc_boot.tv_sec;
- *p++ = nfssvc_boot.tv_usec;
-
+ gen_boot_verifier(&commit->co_verf);
return nfsd_commit(rqstp, &cstate->current_fh, commit->co_offset,
commit->co_count);
}
@@ -873,7 +879,6 @@
{
stateid_t *stateid = &write->wr_stateid;
struct file *filp = NULL;
- u32 *p;
__be32 status = nfs_ok;
unsigned long cnt;
@@ -895,9 +900,7 @@
cnt = write->wr_buflen;
write->wr_how_written = write->wr_stable_how;
- p = (u32 *)write->wr_verifier.data;
- *p++ = nfssvc_boot.tv_sec;
- *p++ = nfssvc_boot.tv_usec;
+ gen_boot_verifier(&write->wr_verifier);
status = nfsd_write(rqstp, &cstate->current_fh, filp,
write->wr_offset, rqstp->rq_vec, write->wr_vlen,