[PATCH] sanitize svc_export_parse()

clean up the exit paths, get rid of nameidata

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c
index 9dc036f..2fa61f0 100644 (file)
--- a/fs/nfsd/export.c
+++ b/fs/nfsd/export.c
@@ -500,35 +500,22 @@ static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen)
        int len;
        int err;
        struct auth_domain *dom = NULL;
-       struct nameidata nd;
-       struct svc_export exp, *expp;
+       struct svc_export exp = {}, *expp;
        int an_int;
 
-       nd.path.dentry = NULL;
-       exp.ex_pathname = NULL;
-
-       /* fs locations */
-       exp.ex_fslocs.locations = NULL;
-       exp.ex_fslocs.locations_count = 0;
-       exp.ex_fslocs.migrated = 0;
-
-       exp.ex_uuid = NULL;
-
-       /* secinfo */
-       exp.ex_nflavors = 0;
-
        if (mesg[mlen-1] != '\n')
                return -EINVAL;
        mesg[mlen-1] = 0;
 
        buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
-       err = -ENOMEM;
-       if (!buf) goto out;
+       if (!buf)
+               return -ENOMEM;
 
        /* client */
-       len = qword_get(&mesg, buf, PAGE_SIZE);
        err = -EINVAL;
-       if (len <= 0) goto out;
+       len = qword_get(&mesg, buf, PAGE_SIZE);
+       if (len <= 0)
+               goto out;
 
        err = -ENOENT;
        dom = auth_domain_find(buf);
@@ -537,25 +524,25 @@ static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen)
 
        /* path */
        err = -EINVAL;
-       if ((len=qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
-               goto out;
-       err = path_lookup(buf, 0, &nd);
-       if (err) goto out_no_path;
+       if ((len = qword_get(&mesg, buf, PAGE_SIZE)) <= 0)
+               goto out1;
+
+       err = kern_path(buf, 0, &exp.ex_path);
+       if (err)
+               goto out1;
 
-       exp.h.flags = 0;
        exp.ex_client = dom;
-       exp.ex_path.mnt = nd.path.mnt;
-       exp.ex_path.dentry = nd.path.dentry;
-       exp.ex_pathname = kstrdup(buf, GFP_KERNEL);
+
        err = -ENOMEM;
+       exp.ex_pathname = kstrdup(buf, GFP_KERNEL);
        if (!exp.ex_pathname)
-               goto out;
+               goto out2;
 
        /* expiry */
        err = -EINVAL;
        exp.h.expiry_time = get_expiry(&mesg);
        if (exp.h.expiry_time == 0)
-               goto out;
+               goto out3;
 
        /* flags */
        err = get_int(&mesg, &an_int);
@@ -563,22 +550,26 @@ static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen)
                err = 0;
                set_bit(CACHE_NEGATIVE, &exp.h.flags);
        } else {
-               if (err || an_int < 0) goto out;        
+               if (err || an_int < 0)
+                       goto out3;
                exp.ex_flags= an_int;
        
                /* anon uid */
                err = get_int(&mesg, &an_int);
-               if (err) goto out;
+               if (err)
+                       goto out3;
                exp.ex_anon_uid= an_int;
 
                /* anon gid */
                err = get_int(&mesg, &an_int);
-               if (err) goto out;
+               if (err)
+                       goto out3;
                exp.ex_anon_gid= an_int;
 
                /* fsid */
                err = get_int(&mesg, &an_int);
-               if (err) goto out;
+               if (err)
+                       goto out3;
                exp.ex_fsid = an_int;
 
                while ((len = qword_get(&mesg, buf, PAGE_SIZE)) > 0) {
@@ -604,12 +595,13 @@ static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen)
                                 */
                                break;
                        if (err)
-                               goto out;
+                               goto out4;
                }
 
-               err = check_export(nd.path.dentry->d_inode, exp.ex_flags,
+               err = check_export(exp.ex_path.dentry->d_inode, exp.ex_flags,
                                   exp.ex_uuid);
-               if (err) goto out;
+               if (err)
+                       goto out4;
        }
 
        expp = svc_export_lookup(&exp);
@@ -622,15 +614,16 @@ static int svc_export_parse(struct cache_detail *cd, char *mesg, int mlen)
                err = -ENOMEM;
        else
                exp_put(expp);
- out:
+out4:
        nfsd4_fslocs_free(&exp.ex_fslocs);
        kfree(exp.ex_uuid);
+out3:
        kfree(exp.ex_pathname);
-       if (nd.path.dentry)
-               path_put(&nd.path);
- out_no_path:
-       if (dom)
-               auth_domain_put(dom);
+out2:
+       path_put(&exp.ex_path);
+out1:
+       auth_domain_put(dom);
+out:
        kfree(buf);
        return err;
 }