[PATCH] Fix failure to update dirpath

[Jeremy Allison]

On Tue, Aug 21, 2018 at 04:51:38AM +0530, Anoop C S wrote:
> 
> To be more precise, parent_dirname() inside check_parent_exists() correctly puts "." into *parent
> (which is nothing but parent_fname.base_name). It is just that we did not copy that over to
> *pp_dirpath before returning from check_parent_exists(). 

OK, I think this is the correct fix. Can you confirm it works
with your setup and I'll submit for review ?

Thanks,

	Jeremy.
-------------- next part --------------
diff --git a/source3/smbd/filename.c b/source3/smbd/filename.c
index 9e15af1916d..39b570fc109 100644
--- a/source3/smbd/filename.c
+++ b/source3/smbd/filename.c
@@ -164,11 +164,10 @@ static NTSTATUS check_parent_exists(TALLOC_CTX *ctx,
 				char **pp_dirpath,
 				char **pp_start)
 {
-	struct smb_filename parent_fname;
+	struct smb_filename parent_fname = { 0 };
 	const char *last_component = NULL;
 	NTSTATUS status;
 	int ret;
-	bool parent_fname_has_wild = false;
 
 	ZERO_STRUCT(parent_fname);
 	if (!parent_dirname(ctx, smb_fname->base_name,
@@ -178,18 +177,18 @@ static NTSTATUS check_parent_exists(TALLOC_CTX *ctx,
 	}
 
 	if (!posix_pathnames) {
-		parent_fname_has_wild = ms_has_wild(parent_fname.base_name);
+		if (ms_has_wild(parent_fname.base_name)) {
+			goto no_optimization_out;
+		}
 	}
 
 	/*
 	 * If there was no parent component in
-	 * smb_fname->base_name of the parent name
-	 * contained a wildcard then don't do this
+	 * smb_fname->base_name then don't do this
 	 * optimization.
 	 */
-	if ((smb_fname->base_name == last_component) ||
-			parent_fname_has_wild) {
-		return NT_STATUS_OK;
+	if (smb_fname->base_name == last_component) {
+		goto no_optimization_out;
 	}
 
 	if (posix_pathnames) {
@@ -202,7 +201,7 @@ static NTSTATUS check_parent_exists(TALLOC_CTX *ctx,
 	   with the normal tree walk. */
 
 	if (ret == -1) {
-		return NT_STATUS_OK;
+		goto no_optimization_out;
 	}
 
 	status = check_for_dot_component(&parent_fname);
@@ -235,6 +234,28 @@ static NTSTATUS check_parent_exists(TALLOC_CTX *ctx,
 		*pp_start));
 
 	return NT_STATUS_OK;
+
+  no_optimization_out:
+
+	/*
+	 * We must still return an *pp_dirpath
+	 * initialized to ".", and a *pp_start
+	 * pointing at smb_fname->base_name.
+	 */
+
+	TALLOC_FREE(parent_fname.base_name);
+
+	*pp_dirpath = talloc_strdup(ctx, ".");
+	if (*pp_dirpath == NULL) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	/*
+	 * Safe to use discard_const_p
+	 * here as by convention smb_fname->base_name
+	 * is allocated off ctx.
+	 */
+	*pp_start = discard_const_p(char, smb_fname->base_name);
+	return NT_STATUS_OK;
 }
 
 /*