NFSD: Fix .pc_release method for NFSv2

nfsd_release_fhandle() assumes that rqstp->rq_resp always points to
an nfsd_fhandle struct. In fact, no NFSv2 procedure uses struct
nfsd_fhandle as its response structure.

So far that has been "safe" to do because the res structs put the
resp->fh field at that same offset as struct nfsd_fhandle. I don't
think that's a guarantee, though, and there is certainly nothing
preventing a developer from altering the fields in those structures.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
Chuck Lever 2020-10-01 18:59:44 -04:00 committed by J. Bruce Fields
parent 7cf8357043
commit 1841b9b614
3 changed files with 26 additions and 11 deletions

View file

@ -611,7 +611,7 @@ static const struct svc_procedure nfsd_procedures2[18] = {
.pc_func = nfsd_proc_getattr,
.pc_decode = nfssvc_decode_fhandle,
.pc_encode = nfssvc_encode_attrstat,
.pc_release = nfssvc_release_fhandle,
.pc_release = nfssvc_release_attrstat,
.pc_argsize = sizeof(struct nfsd_fhandle),
.pc_ressize = sizeof(struct nfsd_attrstat),
.pc_cachetype = RC_NOCACHE,
@ -621,7 +621,7 @@ static const struct svc_procedure nfsd_procedures2[18] = {
.pc_func = nfsd_proc_setattr,
.pc_decode = nfssvc_decode_sattrargs,
.pc_encode = nfssvc_encode_attrstat,
.pc_release = nfssvc_release_fhandle,
.pc_release = nfssvc_release_attrstat,
.pc_argsize = sizeof(struct nfsd_sattrargs),
.pc_ressize = sizeof(struct nfsd_attrstat),
.pc_cachetype = RC_REPLBUFF,
@ -640,7 +640,7 @@ static const struct svc_procedure nfsd_procedures2[18] = {
.pc_func = nfsd_proc_lookup,
.pc_decode = nfssvc_decode_diropargs,
.pc_encode = nfssvc_encode_diropres,
.pc_release = nfssvc_release_fhandle,
.pc_release = nfssvc_release_diropres,
.pc_argsize = sizeof(struct nfsd_diropargs),
.pc_ressize = sizeof(struct nfsd_diropres),
.pc_cachetype = RC_NOCACHE,
@ -659,7 +659,7 @@ static const struct svc_procedure nfsd_procedures2[18] = {
.pc_func = nfsd_proc_read,
.pc_decode = nfssvc_decode_readargs,
.pc_encode = nfssvc_encode_readres,
.pc_release = nfssvc_release_fhandle,
.pc_release = nfssvc_release_readres,
.pc_argsize = sizeof(struct nfsd_readargs),
.pc_ressize = sizeof(struct nfsd_readres),
.pc_cachetype = RC_NOCACHE,
@ -678,7 +678,7 @@ static const struct svc_procedure nfsd_procedures2[18] = {
.pc_func = nfsd_proc_write,
.pc_decode = nfssvc_decode_writeargs,
.pc_encode = nfssvc_encode_attrstat,
.pc_release = nfssvc_release_fhandle,
.pc_release = nfssvc_release_attrstat,
.pc_argsize = sizeof(struct nfsd_writeargs),
.pc_ressize = sizeof(struct nfsd_attrstat),
.pc_cachetype = RC_REPLBUFF,
@ -688,7 +688,7 @@ static const struct svc_procedure nfsd_procedures2[18] = {
.pc_func = nfsd_proc_create,
.pc_decode = nfssvc_decode_createargs,
.pc_encode = nfssvc_encode_diropres,
.pc_release = nfssvc_release_fhandle,
.pc_release = nfssvc_release_diropres,
.pc_argsize = sizeof(struct nfsd_createargs),
.pc_ressize = sizeof(struct nfsd_diropres),
.pc_cachetype = RC_REPLBUFF,
@ -734,7 +734,7 @@ static const struct svc_procedure nfsd_procedures2[18] = {
.pc_func = nfsd_proc_mkdir,
.pc_decode = nfssvc_decode_createargs,
.pc_encode = nfssvc_encode_diropres,
.pc_release = nfssvc_release_fhandle,
.pc_release = nfssvc_release_diropres,
.pc_argsize = sizeof(struct nfsd_createargs),
.pc_ressize = sizeof(struct nfsd_diropres),
.pc_cachetype = RC_REPLBUFF,

View file

@ -561,10 +561,23 @@ nfssvc_encode_entry(void *ccdv, const char *name,
/*
* XDR release functions
*/
void
nfssvc_release_fhandle(struct svc_rqst *rqstp)
void nfssvc_release_attrstat(struct svc_rqst *rqstp)
{
struct nfsd_fhandle *resp = rqstp->rq_resp;
struct nfsd_attrstat *resp = rqstp->rq_resp;
fh_put(&resp->fh);
}
void nfssvc_release_diropres(struct svc_rqst *rqstp)
{
struct nfsd_diropres *resp = rqstp->rq_resp;
fh_put(&resp->fh);
}
void nfssvc_release_readres(struct svc_rqst *rqstp)
{
struct nfsd_readres *resp = rqstp->rq_resp;
fh_put(&resp->fh);
}

View file

@ -156,7 +156,9 @@ int nfssvc_encode_readdirres(struct svc_rqst *, __be32 *);
int nfssvc_encode_entry(void *, const char *name,
int namlen, loff_t offset, u64 ino, unsigned int);
void nfssvc_release_fhandle(struct svc_rqst *);
void nfssvc_release_attrstat(struct svc_rqst *rqstp);
void nfssvc_release_diropres(struct svc_rqst *rqstp);
void nfssvc_release_readres(struct svc_rqst *rqstp);
/* Helper functions for NFSv2 ACL code */
__be32 *nfs2svc_encode_fattr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp, struct kstat *stat);