From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Mon, 21 Apr 2025 20:51:37 +0000 (-0300)
Subject: iconv: Fix UB on iconv/tst-translit-mchar
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=43ba3b5c3afe9cefdaa3fa54404af0e4f3acf944;p=thirdparty%2Fglibc.git

iconv: Fix UB on iconv/tst-translit-mchar

Building with ubsan, the test triggers:

UBSAN: Undefined behaviour in programs/locfile.c:598:3 null pointer passed as argument 2, nonnull attribute declared at unknown:0:0

The obstack_grow is only define for size > 0.
---

diff --git a/locale/programs/locfile.c b/locale/programs/locfile.c
index 7907c949ea..0b66a6bde1 100644
--- a/locale/programs/locfile.c
+++ b/locale/programs/locfile.c
@@ -595,6 +595,8 @@ void
 add_locale_raw_data (struct locale_file *file, const void *data, size_t size)
 {
   record_offset (file);
+  if (size == 0)
+    return;
   obstack_grow (&file->data, data, size);
 }