Fixed parsing of mount options when doing DFS submount
[linux-2.6.git] / fs / cifs / cifs_dfs_ref.c
index d2c8eef..e1c1836 100644 (file)
@@ -106,7 +106,8 @@ static char *cifs_get_share_name(const char *node_name)
 /**
  * compose_mount_options       -       creates mount options for refferral
  * @sb_mountdata:      parent/root DFS mount options (template)
- * @ref_unc:           refferral server UNC
+ * @dentry:            point where we are going to mount
+ * @ref:               server's referral
  * @devname:           pointer for saving device name
  *
  * creates mount options for submount based on template options sb_mountdata
@@ -116,7 +117,8 @@ static char *cifs_get_share_name(const char *node_name)
  * Caller is responcible for freeing retunrned value if it is not error.
  */
 static char *compose_mount_options(const char *sb_mountdata,
-                                  const char *ref_unc,
+                                  struct dentry *dentry,
+                                  const struct dfs_info3_param *ref,
                                   char **devname)
 {
        int rc;
@@ -126,11 +128,12 @@ static char *compose_mount_options(const char *sb_mountdata,
        char *srvIP = NULL;
        char sep = ',';
        int off, noff;
+       char *fullpath;
 
        if (sb_mountdata == NULL)
                return ERR_PTR(-EINVAL);
 
-       *devname = cifs_get_share_name(ref_unc);
+       *devname = cifs_get_share_name(ref->node_name);
        rc = dns_resolve_server_name_to_ip(*devname, &srvIP);
        if (rc != 0) {
                cERROR(1, ("%s: Failed to resolve server part of %s to IP",
@@ -138,7 +141,12 @@ static char *compose_mount_options(const char *sb_mountdata,
                mountdata = ERR_PTR(rc);
                goto compose_mount_options_out;
        }
-       md_len = strlen(sb_mountdata) + strlen(srvIP) + strlen(ref_unc) + 3;
+       /* md_len = strlen(...) + 12 for 'sep+prefixpath='
+        * assuming that we have 'unc=' and 'ip=' in
+        * the original sb_mountdata
+        */
+       md_len = strlen(sb_mountdata) + strlen(srvIP) +
+               strlen(ref->node_name) + 12;
        mountdata = kzalloc(md_len+1, GFP_KERNEL);
        if (mountdata == NULL) {
                mountdata = ERR_PTR(-ENOMEM);
@@ -152,41 +160,56 @@ static char *compose_mount_options(const char *sb_mountdata,
                        strncpy(mountdata, sb_mountdata, 5);
                        off += 5;
        }
-       while ((tkn_e = strchr(sb_mountdata+off, sep))) {
-               noff = (tkn_e - (sb_mountdata+off)) + 1;
-               if (strnicmp(sb_mountdata+off, "unc=", 4) == 0) {
+
+       do {
+               tkn_e = strchr(sb_mountdata + off, sep);
+               if (tkn_e == NULL)
+                       noff = strlen(sb_mountdata + off);
+               else
+                       noff = tkn_e - (sb_mountdata + off) + 1;
+
+               if (strnicmp(sb_mountdata + off, "unc=", 4) == 0) {
                        off += noff;
                        continue;
                }
-               if (strnicmp(sb_mountdata+off, "ip=", 3) == 0) {
+               if (strnicmp(sb_mountdata + off, "ip=", 3) == 0) {
                        off += noff;
                        continue;
                }
-               if (strnicmp(sb_mountdata+off, "prefixpath=", 3) == 0) {
+               if (strnicmp(sb_mountdata + off, "prefixpath=", 11) == 0) {
                        off += noff;
                        continue;
                }
-               strncat(mountdata, sb_mountdata+off, noff);
+               strncat(mountdata, sb_mountdata + off, noff);
                off += noff;
-       }
-       strcat(mountdata, sb_mountdata+off);
+       } while (tkn_e);
+       strcat(mountdata, sb_mountdata + off);
        mountdata[md_len] = '\0';
 
        /* copy new IP and ref share name */
-       strcat(mountdata, ",ip=");
+       if (mountdata[strlen(mountdata) - 1] != sep)
+               strncat(mountdata, &sep, 1);
+       strcat(mountdata, "ip=");
        strcat(mountdata, srvIP);
-       strcat(mountdata, ",unc=");
+       strncat(mountdata, &sep, 1);
+       strcat(mountdata, "unc=");
        strcat(mountdata, *devname);
 
        /* find & copy prefixpath */
-       tkn_e = strchr(ref_unc+2, '\\');
-       if (tkn_e) {
-               tkn_e = strchr(tkn_e+1, '\\');
-               if (tkn_e) {
-                       strcat(mountdata, ",prefixpath=");
-                       strcat(mountdata, tkn_e+1);
-               }
+       tkn_e = strchr(ref->node_name + 2, '\\');
+       if (tkn_e == NULL) /* invalid unc, missing share name*/
+               goto compose_mount_options_out;
+
+       fullpath = build_path_from_dentry(dentry);
+       tkn_e = strchr(tkn_e + 1, '\\');
+       if (tkn_e || strlen(fullpath) - (ref->path_consumed)) {
+               strncat(mountdata, &sep, 1);
+               strcat(mountdata, "prefixpath=");
+               if (tkn_e)
+                       strcat(mountdata, tkn_e + 1);
+               strcat(mountdata, fullpath + (ref->path_consumed));
        }
+       kfree(fullpath);
 
        /*cFYI(1,("%s: parent mountdata: %s", __func__,sb_mountdata));*/
        /*cFYI(1, ("%s: submount mountdata: %s", __func__, mountdata ));*/
@@ -198,7 +221,7 @@ compose_mount_options_out:
 
 
 static struct vfsmount *cifs_dfs_do_refmount(const struct vfsmount *mnt_parent,
-               struct dentry *dentry, char *ref_unc)
+               struct dentry *dentry, const struct dfs_info3_param *ref)
 {
        struct cifs_sb_info *cifs_sb;
        struct vfsmount *mnt;
@@ -207,7 +230,7 @@ static struct vfsmount *cifs_dfs_do_refmount(const struct vfsmount *mnt_parent,
 
        cifs_sb = CIFS_SB(dentry->d_inode->i_sb);
        mountdata = compose_mount_options(cifs_sb->mountdata,
-                                               ref_unc, &devname);
+                                               dentry, ref, &devname);
 
        if (IS_ERR(mountdata))
                return (struct vfsmount *)mountdata;
@@ -310,7 +333,7 @@ cifs_dfs_follow_mountpoint(struct dentry *dentry, struct nameidata *nd)
                        }
                        mnt = cifs_dfs_do_refmount(nd->path.mnt,
                                                nd->path.dentry,
-                                               referrals[i].node_name);
+                                               referrals + i);
                        cFYI(1, ("%s: cifs_dfs_do_refmount:%s , mnt:%p",
                                         __func__,
                                        referrals[i].node_name, mnt));