knfsd: nfsd: make all exp_finding functions return -errno's on err
Currently exp_find(), exp_get_by_name(), and friends, return an export on
success, and on failure return:
errors -EAGAIN (drop this request pending an upcall) or
-ETIMEDOUT (an upcall has timed out), or
return NULL, which can mean either that there was a memory allocation
failure, or that an export was not found, or that a passed-in
export lacks an auth_domain.
Many callers seem to assume that NULL means that an export was not found,
which may lead to bugs in the case of a memory allocation failure.
Modify these functions to distinguish between the two NULL cases by returning
either -ENOENT or -ENOMEM. They now never return NULL. We get to simplify
some code in the process.
We return -ENOENT in the case of a missing auth_domain. This case should
probably be removed (or converted to a bug) after confirming that it can never
happen.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 8d6b5c4..0a18149 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -192,15 +192,14 @@
exp2 = exp_parent(exp->ex_client, mnt, dentry,
&rqstp->rq_chandle);
- if (IS_ERR(exp2)) {
+ if (PTR_ERR(exp2) == -ENOENT) {
+ dput(dentry);
+ dentry = dget(dparent);
+ } else if (IS_ERR(exp2)) {
host_err = PTR_ERR(exp2);
dput(dentry);
mntput(mnt);
goto out_nfserr;
- }
- if (!exp2) {
- dput(dentry);
- dentry = dget(dparent);
} else {
exp_put(exp);
exp = exp2;