+2018-09-23 Bruno Haible <bruno@clisp.org>
+
+ vasnprintf: Fix heap memory overrun bug.
+ Reported by Ben Pfaff <blp@cs.stanford.edu> in
+ <https://lists.gnu.org/archive/html/bug-gnulib/2018-09/msg00107.html>.
+ * lib/vasnprintf.c (convert_to_decimal): Allocate one more byte of
+ memory.
+ * tests/test-vasnprintf.c (test_function): Add another test.
+
2018-09-19 Paul Eggert <eggert@cs.ucla.edu>
maint: mktime.c now shared with glibc
size_t a_len = a.nlimbs;
/* 0.03345 is slightly larger than log(2)/(9*log(10)). */
size_t c_len = 9 * ((size_t)(a_len * (GMP_LIMB_BITS * 0.03345f)) + 1);
- char *c_ptr = (char *) malloc (xsum (c_len, extra_zeroes));
+ /* We need extra_zeroes bytes for zeroes, followed by c_len bytes for the
+ digits of a, followed by 1 byte for the terminating NUL. */
+ char *c_ptr = (char *) malloc (xsum (xsum (extra_zeroes, c_len), 1));
if (c_ptr != NULL)
{
char *d_ptr = c_ptr;
ASSERT (result != NULL);
ASSERT (strcmp (result, "12345") == 0);
ASSERT (length == 5);
- if (size < 6)
+ if (size < 5 + 1)
+ ASSERT (result != buf);
+ ASSERT (memcmp (buf + size, &"DEADBEEF"[size], 8 - size) == 0);
+ if (result != buf)
+ free (result);
+ }
+
+ /* Note: This test assumes IEEE 754 representation of 'double' floats. */
+ for (size = 0; size <= 8; size++)
+ {
+ size_t length;
+ char *result;
+
+ memcpy (buf, "DEADBEEF", 8);
+ length = size;
+ result = my_asnprintf (buf, &length, "%2.0f", 1.6314159265358979e+125);
+ ASSERT (result != NULL);
+ ASSERT (strcmp (result, "163141592653589790215729350939528493057529598899734151772468186268423257777068536614838678161083520756952076273094236944990208") == 0);
+ ASSERT (length == 126);
+ if (size < 126 + 1)
ASSERT (result != buf);
ASSERT (memcmp (buf + size, &"DEADBEEF"[size], 8 - size) == 0);
if (result != buf)