NFS: 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.
Fix this by using a __be32 array to generate a verifier's contents,
and then byte-copy the contents into the verifier field. The contents
of a verifier, for all intents and purposes, are opaque bytes. Only
local code that generates a verifier need know the actual content and
format. Everyone else compares the full byte array for exact
equality.
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: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index e0e3528..1ec0522 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -836,13 +836,15 @@
p->o_arg.dir_bitmask = server->cache_consistency_bitmask;
p->o_arg.claim = NFS4_OPEN_CLAIM_NULL;
if (attrs != NULL && attrs->ia_valid != 0) {
- u32 *s;
+ __be32 verf[2];
p->o_arg.u.attrs = &p->attrs;
memcpy(&p->attrs, attrs, sizeof(p->attrs));
- s = (u32 *) p->o_arg.u.verifier.data;
- s[0] = jiffies;
- s[1] = current->pid;
+
+ verf[0] = jiffies;
+ verf[1] = current->pid;
+ memcpy(p->o_arg.u.verifier.data, verf,
+ sizeof(p->o_arg.u.verifier.data));
}
p->c_arg.fh = &p->o_res.fh;
p->c_arg.stateid = &p->o_res.stateid;
@@ -3819,6 +3821,16 @@
return -EAGAIN;
}
+static void nfs4_construct_boot_verifier(struct nfs_client *clp,
+ nfs4_verifier *bootverf)
+{
+ __be32 verf[2];
+
+ verf[0] = htonl((u32)clp->cl_boot_time.tv_sec);
+ verf[1] = htonl((u32)clp->cl_boot_time.tv_nsec);
+ memcpy(bootverf->data, verf, sizeof(bootverf->data));
+}
+
int nfs4_proc_setclientid(struct nfs_client *clp, u32 program,
unsigned short port, struct rpc_cred *cred,
struct nfs4_setclientid_res *res)
@@ -3835,13 +3847,10 @@
.rpc_resp = res,
.rpc_cred = cred,
};
- __be32 *p;
int loop = 0;
int status;
- p = (__be32*)sc_verifier.data;
- *p++ = htonl((u32)clp->cl_boot_time.tv_sec);
- *p = htonl((u32)clp->cl_boot_time.tv_nsec);
+ nfs4_construct_boot_verifier(clp, &sc_verifier);
for(;;) {
rcu_read_lock();
@@ -4933,6 +4942,7 @@
{
nfs4_verifier verifier;
struct nfs41_exchange_id_args args = {
+ .verifier = &verifier,
.client = clp,
.flags = EXCHGID4_FLAG_SUPP_MOVED_REFER,
};
@@ -4946,15 +4956,11 @@
.rpc_resp = &res,
.rpc_cred = cred,
};
- __be32 *p;
dprintk("--> %s\n", __func__);
BUG_ON(clp == NULL);
- p = (u32 *)verifier.data;
- *p++ = htonl((u32)clp->cl_boot_time.tv_sec);
- *p = htonl((u32)clp->cl_boot_time.tv_nsec);
- args.verifier = &verifier;
+ nfs4_construct_boot_verifier(clp, &verifier);
args.id_len = scnprintf(args.id, sizeof(args.id),
"%s/%s.%s/%u",
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index e9d4ac0..62effaf 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -1538,7 +1538,7 @@
FATTR4_WORD1_MOUNTED_ON_FILEID,
};
uint32_t dircount = readdir->count >> 1;
- __be32 *p;
+ __be32 *p, verf[2];
if (readdir->plus) {
attrs[0] |= FATTR4_WORD0_TYPE|FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE|
@@ -1553,10 +1553,11 @@
if (!(readdir->bitmask[1] & FATTR4_WORD1_MOUNTED_ON_FILEID))
attrs[0] |= FATTR4_WORD0_FILEID;
- p = reserve_space(xdr, 12+NFS4_VERIFIER_SIZE+20);
+ p = reserve_space(xdr, 12);
*p++ = cpu_to_be32(OP_READDIR);
p = xdr_encode_hyper(p, readdir->cookie);
- p = xdr_encode_opaque_fixed(p, readdir->verifier.data, NFS4_VERIFIER_SIZE);
+ encode_nfs4_verifier(xdr, &readdir->verifier);
+ p = reserve_space(xdr, 20);
*p++ = cpu_to_be32(dircount);
*p++ = cpu_to_be32(readdir->count);
*p++ = cpu_to_be32(2);
@@ -1565,11 +1566,11 @@
*p = cpu_to_be32(attrs[1] & readdir->bitmask[1]);
hdr->nops++;
hdr->replen += decode_readdir_maxsz;
+ memcpy(verf, readdir->verifier.data, sizeof(verf));
dprintk("%s: cookie = %Lu, verifier = %08x:%08x, bitmap = %08x:%08x\n",
__func__,
(unsigned long long)readdir->cookie,
- ((u32 *)readdir->verifier.data)[0],
- ((u32 *)readdir->verifier.data)[1],
+ verf[0], verf[1],
attrs[0] & readdir->bitmask[0],
attrs[1] & readdir->bitmask[1]);
}
@@ -1643,9 +1644,9 @@
{
__be32 *p;
- p = reserve_space(xdr, 4 + NFS4_VERIFIER_SIZE);
- *p++ = cpu_to_be32(OP_SETCLIENTID);
- xdr_encode_opaque_fixed(p, setclientid->sc_verifier->data, NFS4_VERIFIER_SIZE);
+ p = reserve_space(xdr, 4);
+ *p = cpu_to_be32(OP_SETCLIENTID);
+ encode_nfs4_verifier(xdr, setclientid->sc_verifier);
encode_string(xdr, setclientid->sc_name_len, setclientid->sc_name);
p = reserve_space(xdr, 4);
@@ -1662,10 +1663,10 @@
{
__be32 *p;
- p = reserve_space(xdr, 12 + NFS4_VERIFIER_SIZE);
+ p = reserve_space(xdr, 12);
*p++ = cpu_to_be32(OP_SETCLIENTID_CONFIRM);
p = xdr_encode_hyper(p, arg->clientid);
- xdr_encode_opaque_fixed(p, arg->confirm.data, NFS4_VERIFIER_SIZE);
+ encode_nfs4_verifier(xdr, &arg->confirm);
hdr->nops++;
hdr->replen += decode_setclientid_confirm_maxsz;
}
@@ -1708,9 +1709,9 @@
char impl_name[NFS4_OPAQUE_LIMIT];
int len = 0;
- p = reserve_space(xdr, 4 + sizeof(args->verifier->data));
- *p++ = cpu_to_be32(OP_EXCHANGE_ID);
- xdr_encode_opaque_fixed(p, args->verifier->data, sizeof(args->verifier->data));
+ p = reserve_space(xdr, 4);
+ *p = cpu_to_be32(OP_EXCHANGE_ID);
+ encode_nfs4_verifier(xdr, args->verifier);
encode_string(xdr, args->id_len, args->id);
@@ -4162,7 +4163,7 @@
static int decode_verifier(struct xdr_stream *xdr, void *verifier)
{
- return decode_opaque_fixed(xdr, verifier, 8);
+ return decode_opaque_fixed(xdr, verifier, NFS4_VERIFIER_SIZE);
}
static int decode_commit(struct xdr_stream *xdr, struct nfs_writeres *res)
@@ -4854,17 +4855,16 @@
size_t hdrlen;
u32 recvd, pglen = rcvbuf->page_len;
int status;
+ __be32 verf[2];
status = decode_op_hdr(xdr, OP_READDIR);
if (!status)
status = decode_verifier(xdr, readdir->verifier.data);
if (unlikely(status))
return status;
+ memcpy(verf, readdir->verifier.data, sizeof(verf));
dprintk("%s: verifier = %08x:%08x\n",
- __func__,
- ((u32 *)readdir->verifier.data)[0],
- ((u32 *)readdir->verifier.data)[1]);
-
+ __func__, verf[0], verf[1]);
hdrlen = (char *) xdr->p - (char *) iov->iov_base;
recvd = rcvbuf->len - hdrlen;
@@ -5111,7 +5111,7 @@
goto out_overflow;
res->count = be32_to_cpup(p++);
res->verf->committed = be32_to_cpup(p++);
- memcpy(res->verf->verifier, p, 8);
+ memcpy(res->verf->verifier, p, NFS4_VERIFIER_SIZE);
return 0;
out_overflow:
print_overflow_msg(__func__, xdr);
@@ -5455,7 +5455,7 @@
p += 2;
/* Read verifier */
- p = xdr_decode_opaque_fixed(p, verftemp.verifier, 8);
+ p = xdr_decode_opaque_fixed(p, verftemp.verifier, NFS4_VERIFIER_SIZE);
res->num_devs = be32_to_cpup(p);