@@ -1229,6 +1229,30 @@ void dfs_cache_put_refsrv_sessions(const uuid_t *mount_id)
kref_put(&mg->refcount, mount_group_release);
}
+/* Extract share from DFS target and return a pointer to prefix path or NULL */
+static const char *parse_target_share(const char *target, char **share)
+{
+ const char *s, *seps = "/\\";
+ size_t len;
+
+ s = strpbrk(target + 1, seps);
+ if (!s)
+ return ERR_PTR(-EINVAL);
+
+ len = strcspn(s + 1, seps);
+ if (!len)
+ return ERR_PTR(-EINVAL);
+ s += len;
+
+ len = s - target + 1;
+ *share = kstrndup(target, len, GFP_KERNEL);
+ if (!*share)
+ return ERR_PTR(-ENOMEM);
+
+ s = target + len;
+ return s + strspn(s, seps);
+}
+
/**
* dfs_cache_get_tgt_share - parse a DFS target
*
@@ -1242,56 +1266,45 @@ void dfs_cache_put_refsrv_sessions(const uuid_t *mount_id)
int dfs_cache_get_tgt_share(char *path, const struct dfs_cache_tgt_iterator *it, char **share,
char **prefix)
{
- char *s, sep, *p;
- size_t len;
- size_t plen1, plen2;
+ char sep;
+ char *target_share, *ppath;
+ const char *target_ppath, *dfsref_ppath;
+ size_t target_pplen, dfsref_pplen;
+ size_t len, c;
if (!it || !path || !share || !prefix || strlen(path) < it->it_path_consumed)
return -EINVAL;
- *share = NULL;
- *prefix = NULL;
-
sep = it->it_name[0];
if (sep != '\\' && sep != '/')
return -EINVAL;
- s = strchr(it->it_name + 1, sep);
- if (!s)
- return -EINVAL;
+ target_ppath = parse_target_share(it->it_name, &target_share);
+ if (IS_ERR(target_ppath))
+ return PTR_ERR(target_ppath);
- /* point to prefix in target node */
- s = strchrnul(s + 1, sep);
+ /* point to prefix in DFS referral path */
+ dfsref_ppath = path + it->it_path_consumed;
+ dfsref_ppath += strspn(dfsref_ppath, "/\\");
- /* extract target share */
- *share = kstrndup(it->it_name, s - it->it_name, GFP_KERNEL);
- if (!*share)
- return -ENOMEM;
+ target_pplen = strlen(target_ppath);
+ dfsref_pplen = strlen(dfsref_ppath);
- /* skip separator */
- if (*s)
- s++;
- /* point to prefix in DFS path */
- p = path + it->it_path_consumed;
- if (*p == sep)
- p++;
-
- /* merge prefix paths from DFS path and target node */
- plen1 = it->it_name + strlen(it->it_name) - s;
- plen2 = path + strlen(path) - p;
- if (plen1 || plen2) {
- len = plen1 + plen2 + 2;
- *prefix = kmalloc(len, GFP_KERNEL);
- if (!*prefix) {
- kfree(*share);
- *share = NULL;
+ /* merge prefix paths from DFS referral path and target node */
+ if (target_pplen || dfsref_pplen) {
+ len = target_pplen + dfsref_pplen + 2;
+ ppath = kzalloc(len, GFP_KERNEL);
+ if (!ppath) {
+ kfree(target_share);
return -ENOMEM;
}
- if (plen1)
- scnprintf(*prefix, len, "%.*s%c%.*s", (int)plen1, s, sep, (int)plen2, p);
- else
- strscpy(*prefix, p, len);
+ c = strscpy(ppath, target_ppath, len);
+ if (c && dfsref_pplen)
+ ppath[c] = sep;
+ strlcat(ppath, dfsref_ppath, len);
}
+ *share = target_share;
+ *prefix = ppath;
return 0;
}
During DFS failover, prefix paths may change, so make sure to not leave trailing separators when parsing thew in dfs_cache_get_tgt_share(). The separators of prefix paths are already handled by build_path_from_dentry_optional_prefix(). Consider the following DFS link: //dom/dfs/link: [\srv1\share\dir1, \srv2\share\dir1] Before commit: mount.cifs //dom/dfs/link tree connect to \\srv1\share; prefix_path=dir1 disconnect srv1; failover to srv2 tree connect to \\srv2\share; prefix_path=dir1\ mv foo bar ... SMB2 430 Create Request File: dir1\\foo;GetInfo Request FILE_INFO/SMB2_FILE_ALL_INFO;Close Request SMB2 582 Create Response File: dir1\\foo;GetInfo Response;Close Response SMB2 430 Create Request File: dir1\\bar;GetInfo Request FILE_INFO/SMB2_FILE_ALL_INFO;Close Request SMB2 286 Create Response, Error: STATUS_OBJECT_NAME_NOT_FOUND;GetInfo Response, Error: STATUS_OBJECT_NAME_NOT_FOUND;Close Response, Error: STATUS_OBJECT_NAME_NOT_FOUND SMB2 462 Create Request File: dir1\\foo;SetInfo Request FILE_INFO/SMB2_FILE_RENAME_INFO NewName:dir1\\bar;Close Request SMB2 478 Create Response File: dir1\\foo;SetInfo Response, Error: STATUS_OBJECT_NAME_INVALID;Close Response After commit: mount.cifs //dom/dfs/link tree connect to \\srv1\share; prefix_path=dir1 disconnect srv1; failover to srv2 tree connect to \\srv2\share; prefix_path=dir1 mv foo bar ... SMB2 430 Create Request File: dir1\foo;GetInfo Request FILE_INFO/SMB2_FILE_ALL_INFO;Close Request SMB2 582 Create Response File: dir1\foo;GetInfo Response;Close Response SMB2 430 Create Request File: dir1\bar;GetInfo Request FILE_INFO/SMB2_FILE_ALL_INFO;Close Request SMB2 286 Create Response, Error: STATUS_OBJECT_NAME_NOT_FOUND;GetInfo Response, Error: STATUS_OBJECT_NAME_NOT_FOUND;Close Response, Error: STATUS_OBJECT_NAME_NOT_FOUND SMB2 462 Create Request File: dir1\foo;SetInfo Request FILE_INFO/SMB2_FILE_RENAME_INFO NewName:dir1\bar;Close Request SMB2 478 Create Response File: dir1\foo;SetInfo Response;Close Response Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz> --- fs/cifs/dfs_cache.c | 85 ++++++++++++++++++++++++++------------------- 1 file changed, 49 insertions(+), 36 deletions(-)