Return error when attempting to create a policy with commas in name (#20724)

cmd/admin-handlers-users.go

@@ -1719,6 +1719,12 @@ func (a adminAPIHandlers) AddCannedPolicy(w http.ResponseWriter, r *http.Request
 	}
 	setReqInfoPolicyName(ctx, policyName)
 
+	// Reject policy names with commas.
+	if strings.Contains(policyName, ",") {
+		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrPolicyInvalidName), r.URL)
+		return
+	}
+
 	// Error out if Content-Length is missing.
 	if r.ContentLength <= 0 {
 		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrMissingContentLength), r.URL)

cmd/admin-handlers-users_test.go

@@ -716,6 +716,12 @@ func (s *TestSuiteIAM) TestCannedPolicies(c *check) {
 		c.Fatalf("policy info err: %v", err)
 	}
 
+	// Check that policy with comma is rejected.
+	err = s.adm.AddCannedPolicy(ctx, "invalid,policy", policyBytes)
+	if err == nil {
+		c.Fatalf("invalid policy created successfully")
+	}
+
 	infoStr := string(info)
 	if !strings.Contains(infoStr, `"s3:PutObject"`) || !strings.Contains(infoStr, ":"+bucket+"/") {
 		c.Fatalf("policy contains unexpected content!")

cmd/api-errors.go

@@ -213,6 +213,7 @@ const (
 	ErrPolicyAlreadyAttached
 	ErrPolicyNotAttached
 	ErrExcessData
+	ErrPolicyInvalidName
 	// Add new error codes here.
 
 	// SSE-S3/SSE-KMS related API errors
@@ -561,6 +562,11 @@ var errorCodes = errorCodeMap{
 		Description:    "More data provided than indicated content length",
 		HTTPStatusCode: http.StatusBadRequest,
 	},
+	ErrPolicyInvalidName: {
+		Code:           "PolicyInvalidName",
+		Description:    "Policy name may not contain comma",
+		HTTPStatusCode: http.StatusBadRequest,
+	},
 	ErrPolicyTooLarge: {
 		Code:           "PolicyTooLarge",
 		Description:    "Policy exceeds the maximum allowed document size.",