[PATCH v1 20/42] NFSD: Update the MKNOD3args decoder to use struct xdr_stream

Chuck Lever
2021-01-05T15:31:45Z

This commit removes the last usage of the original decode_sattr3(),
so it is removed as a clean-up.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
fs/nfsd/nfs3xdr.c | 107 +++++++++++++++++------------------------------------
1 file changed, 35 insertions(+), 72 deletions(-)

diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c
index e599d1481b2d..5fb7e8a599c4 100644
--- a/fs/nfsd/nfs3xdr.c
+++ b/fs/nfsd/nfs3xdr.c
@@ -103,26 +103,6 @@ encode_fh(__be32 *p, struct svc_fh *fhp)
return p + XDR_QUADLEN(size);
}

-/*
- * Decode a file name and make sure that the path contains
- * no slashes or null bytes.
- */
-static __be32 *
-decode_filename(__be32 *p, char **namp, unsigned int *lenp)
-{
- char *name;
- unsigned int i;
-
- if ((p = xdr_decode_string_inplace(p, namp, lenp, NFS3_MAXNAMLEN)) != NULL) {
- for (i = 0, name = *namp; i < *lenp; i++, name++) {
- if (*name == '\0' || *name == '/')
- return NULL;
- }
- }
-
- return p;
-}
-
static bool
svcxdr_decode_filename3(struct xdr_stream *xdr, char **name, unsigned int *len)
{
@@ -262,49 +242,26 @@ svcxdr_decode_sattrguard3(struct xdr_stream *xdr, struct nfsd3_sattrargs *args)
return true;
}

-static __be32 *
-decode_sattr3(__be32 *p, struct iattr *iap, struct user_namespace *userns)
+static bool
+svcxdr_decode_specdata3(struct xdr_stream *xdr, struct nfsd3_mknodargs *args)
{
- u32 tmp;
+ __be32 *p;

- iap->ia_valid = 0;
+ p = xdr_inline_decode(xdr, XDR_UNIT * 2);
+ if (!p)
+ return false;
+ args->major = be32_to_cpup(p++);
+ args->minor = be32_to_cpup(p);

- if (*p++) {
- iap->ia_valid |= ATTR_MODE;
- iap->ia_mode = ntohl(*p++);
- }
- if (*p++) {
- iap->ia_uid = make_kuid(userns, ntohl(*p++));
- if (uid_valid(iap->ia_uid))
- iap->ia_valid |= ATTR_UID;
- }
- if (*p++) {
- iap->ia_gid = make_kgid(userns, ntohl(*p++));
- if (gid_valid(iap->ia_gid))
- iap->ia_valid |= ATTR_GID;
- }
- if (*p++) {
- u64 newsize;
+ return true;
+}

- iap->ia_valid |= ATTR_SIZE;
- p = xdr_decode_hyper(p, &newsize);
- iap->ia_size = min_t(u64, newsize, NFS_OFFSET_MAX);
- }
- if ((tmp = ntohl(*p++)) == 1) { /* set to server time */
- iap->ia_valid |= ATTR_ATIME;
- } else if (tmp == 2) { /* set to client time */
- iap->ia_valid |= ATTR_ATIME | ATTR_ATIME_SET;
- iap->ia_atime.tv_sec = ntohl(*p++);
- iap->ia_atime.tv_nsec = ntohl(*p++);
- }
- if ((tmp = ntohl(*p++)) == 1) { /* set to server time */
- iap->ia_valid |= ATTR_MTIME;
- } else if (tmp == 2) { /* set to client time */
- iap->ia_valid |= ATTR_MTIME | ATTR_MTIME_SET;
- iap->ia_mtime.tv_sec = ntohl(*p++);
- iap->ia_mtime.tv_nsec = ntohl(*p++);
- }
- return p;
+static bool
+svcxdr_decode_devicedata3(struct svc_rqst *rqstp, struct xdr_stream *xdr,
+ struct nfsd3_mknodargs *args)
+{
+ return svcxdr_decode_sattr3(rqstp, xdr, &args->attrs) &&
+ svcxdr_decode_specdata3(xdr, args);
}

static __be32 *encode_fsid(__be32 *p, struct svc_fh *fhp)
@@ -644,24 +601,30 @@ nfs3svc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p)
int
nfs3svc_decode_mknodargs(struct svc_rqst *rqstp, __be32 *p)
{
+ struct xdr_stream *xdr = &rqstp->rq_arg_stream;
struct nfsd3_mknodargs *args = rqstp->rq_argp;

- if (!(p = decode_fh(p, &args->fh))
- || !(p = decode_filename(p, &args->name, &args->len)))
+ if (!svcxdr_decode_diropargs3(xdr, &args->fh, &args->name, &args->len))
+ return 0;
+ if (xdr_stream_decode_u32(xdr, &args->ftype) < 0)
+ return 0;
+ switch (args->ftype) {
+ case NF3CHR:
+ case NF3BLK:
+ return svcxdr_decode_devicedata3(rqstp, xdr, args);
+ case NF3SOCK:
+ case NF3FIFO:
+ return svcxdr_decode_sattr3(rqstp, xdr, &args->attrs);
+ case NF3REG:
+ case NF3DIR:
+ case NF3LNK:
+ /* Valid XDR but illegal file types */
+ break;
+ default:
return 0;
-
- args->ftype = ntohl(*p++);
-
- if (args->ftype == NF3BLK || args->ftype == NF3CHR
- || args->ftype == NF3SOCK || args->ftype == NF3FIFO)
- p = decode_sattr3(p, &args->attrs, nfsd_user_namespace(rqstp));
-
- if (args->ftype == NF3BLK || args->ftype == NF3CHR) {
- args->major = ntohl(*p++);
- args->minor = ntohl(*p++);
}

- return xdr_argsize_check(rqstp, p);
+ return 1;
}

int