printf: Check precision before writing into stdout (#6511)

* Add a new error type InvalidPrecision

* check if the precision is valid before writing to stdout when it is signedInt, unsigned, or float

* add tests for invalid precision check

* add tests for invalid precision check

* fix possible cross-platform issue that code failing to pass on some tests

* uucore/format: inline var in format string

---------

Co-authored-by: Daniel Hofstetter <daniel.hofstetter@42dh.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/tests/by-util/test_printf.rs b/tests/by-util/test_printf.rs
index 7bf1fcfe5..26f556e8e 100644
--- a/tests/by-util/test_printf.rs
+++ b/tests/by-util/test_printf.rs
@@ -774,3 +774,21 @@ fn format_spec_zero_string_fails() {
     // It is invalid to have the format spec '%0s'
     new_ucmd!().args(&["%0s", "3"]).fails().code_is(1);
 }
+
+#[test]
+fn invalid_precision_fails() {
+    // It is invalid to have length of output string greater than i32::MAX
+    new_ucmd!()
+        .args(&["%.*d", "2147483648", "0"])
+        .fails()
+        .stderr_is("printf: invalid precision: '2147483648'\n");
+}
+
+#[test]
+fn float_invalid_precision_fails() {
+    // It is invalid to have length of output string greater than i32::MAX
+    new_ucmd!()
+        .args(&["%.*f", "2147483648", "0"])
+        .fails()
+        .stderr_is("printf: invalid precision: '2147483648'\n");
+}