Don't lie. If a string can't be converted to a wide (Unicode) string,

return a NULL instead of an incomplete string.  Expand the test coverage
to verify the correct behavior here.

2 files changed, 43 insertions, 1 deletions

diff --git a/lib/libarchive/archive_entry.c b/lib/libarchive/archive_entry.c
index 8fbc0ac..8da0215 100644
--- a/lib/libarchive/archive_entry.c
+++ b/lib/libarchive/archive_entry.c
@@ -207,6 +207,8 @@ aes_get_mbs(struct aes *aes)
 static const wchar_t *
 aes_get_wcs(struct aes *aes)
 {
+	int r;
+
 	if (aes->aes_wcs == NULL && aes->aes_mbs == NULL)
 		return NULL;
 	if (aes->aes_wcs == NULL && aes->aes_mbs != NULL) {
@@ -221,8 +223,13 @@ aes_get_wcs(struct aes *aes)
 		aes->aes_wcs = aes->aes_wcs_alloc;
 		if (aes->aes_wcs == NULL)
 			__archive_errx(1, "No memory for aes_get_wcs()");
-		mbstowcs(aes->aes_wcs_alloc, aes->aes_mbs, wcs_length);
+		r = mbstowcs(aes->aes_wcs_alloc, aes->aes_mbs, wcs_length);
 		aes->aes_wcs_alloc[wcs_length] = 0;
+		if (r == -1) {
+			/* Conversion failed, don't lie to our clients. */
+			free(aes->aes_wcs_alloc);
+			aes->aes_wcs = aes->aes_wcs_alloc = NULL;
+		}
 	}
 	return (aes->aes_wcs);
 }
diff --git a/lib/libarchive/test/test_entry.c b/lib/libarchive/test/test_entry.c
index 3fd1d06..638af48 100644
--- a/lib/libarchive/test/test_entry.c
+++ b/lib/libarchive/test/test_entry.c
@@ -25,6 +25,8 @@
 #include "test.h"
 __FBSDID("$FreeBSD$");
 
+#include <locale.h>
+
 /*
  * Most of these tests are system-independent, though a few depend on
  * features of the local system.  Such tests are conditionalized on
@@ -721,6 +723,39 @@ DEFINE_TEST(test_entry)
 #endif
 #endif
 
+	/*
+	 * Exercise the character-conversion logic, if we can.
+	 */
+	failure("Can't exercise charset-conversion logic.");
+	if (assert(NULL != setlocale(LC_ALL, "de_DE.UTF-8"))) {
+		/* A filename that cannot be converted to wide characters. */
+		archive_entry_copy_pathname(e, "abc\314\214mno\374xyz");
+		failure("Converting invalid chars to Unicode should fail.");
+		assert(NULL == archive_entry_pathname_w(e));
+		//failure("Converting invalid chars to UTF-8 should fail.");
+		//assert(NULL == archive_entry_pathname_utf8(e));
+
+		/* A group name that cannot be converted. */
+		archive_entry_copy_gname(e, "abc\314\214mno\374xyz");
+		failure("Converting invalid chars to Unicode should fail.");
+		assert(NULL == archive_entry_gname_w(e));
+
+		/* A user name that cannot be converted. */
+		archive_entry_copy_uname(e, "abc\314\214mno\374xyz");
+		failure("Converting invalid chars to Unicode should fail.");
+		assert(NULL == archive_entry_uname_w(e));
+
+		/* A hardlink target that cannot be converted. */
+		archive_entry_copy_hardlink(e, "abc\314\214mno\374xyz");
+		failure("Converting invalid chars to Unicode should fail.");
+		assert(NULL == archive_entry_hardlink_w(e));
+
+		/* A symlink target that cannot be converted. */
+		archive_entry_copy_symlink(e, "abc\314\214mno\374xyz");
+		failure("Converting invalid chars to Unicode should fail.");
+		assert(NULL == archive_entry_symlink_w(e));
+	}
+
 	/* Release the experimental entry. */
 	archive_entry_free(e);
 }