[PATCH] bug: nfsd/nfs4xdr.c misuse of ERR_PTR()

a) ERR_PTR(nfserr_something) is a bad idea;
IS_ERR() will be false for it.
	b) mixing nfserr_.... with -EOPNOTSUPP is
even worse idea.

nfsd4_path() does both; caller expects to get NFS protocol error out it if
anything goes wrong, but if it does we either do not notice (see (a)) or get
host-endian negative (see (b)).

IOW, that's a case when we can't use ERR_PTR() to return error, even though we
return a pointer in case of success.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Al Viro 2006-10-19 23:28:44 -07:00 committed by Linus Torvalds
parent b7766da7f7
commit cc45f01750

View file

@ -1292,16 +1292,15 @@ static int nfsd4_encode_fs_location4(struct nfsd4_fs_location *location,
* Returned string is safe to use as long as the caller holds a reference * Returned string is safe to use as long as the caller holds a reference
* to @exp. * to @exp.
*/ */
static char *nfsd4_path(struct svc_rqst *rqstp, struct svc_export *exp) static char *nfsd4_path(struct svc_rqst *rqstp, struct svc_export *exp, u32 *stat)
{ {
struct svc_fh tmp_fh; struct svc_fh tmp_fh;
char *path, *rootpath; char *path, *rootpath;
int stat;
fh_init(&tmp_fh, NFS4_FHSIZE); fh_init(&tmp_fh, NFS4_FHSIZE);
stat = exp_pseudoroot(rqstp->rq_client, &tmp_fh, &rqstp->rq_chandle); *stat = exp_pseudoroot(rqstp->rq_client, &tmp_fh, &rqstp->rq_chandle);
if (stat) if (*stat)
return ERR_PTR(stat); return NULL;
rootpath = tmp_fh.fh_export->ex_path; rootpath = tmp_fh.fh_export->ex_path;
path = exp->ex_path; path = exp->ex_path;
@ -1309,7 +1308,8 @@ static char *nfsd4_path(struct svc_rqst *rqstp, struct svc_export *exp)
if (strncmp(path, rootpath, strlen(rootpath))) { if (strncmp(path, rootpath, strlen(rootpath))) {
printk("nfsd: fs_locations failed;" printk("nfsd: fs_locations failed;"
"%s is not contained in %s\n", path, rootpath); "%s is not contained in %s\n", path, rootpath);
return ERR_PTR(-EOPNOTSUPP); *stat = nfserr_notsupp;
return NULL;
} }
return path + strlen(rootpath); return path + strlen(rootpath);
@ -1322,13 +1322,14 @@ static int nfsd4_encode_fs_locations(struct svc_rqst *rqstp,
struct svc_export *exp, struct svc_export *exp,
u32 **pp, int *buflen) u32 **pp, int *buflen)
{ {
int status, i; u32 status;
int i;
u32 *p = *pp; u32 *p = *pp;
struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs; struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
char *root = nfsd4_path(rqstp, exp); char *root = nfsd4_path(rqstp, exp, &status);
if (IS_ERR(root)) if (status)
return PTR_ERR(root); return status;
status = nfsd4_encode_components('/', root, &p, buflen); status = nfsd4_encode_components('/', root, &p, buflen);
if (status) if (status)
return status; return status;