* src/hash.c (jhash_string): Don't read past end of string.
Original patch from Dmitry Goncharov <dgoncharov@users.sf.net>.
diff --git a/src/hash.c b/src/hash.c
index bd3892e..004097d 100644
--- a/src/hash.c
+++ b/src/hash.c
@@ -16,6 +16,7 @@
#include "makeint.h"
#include "hash.h"
+#include <assert.h>
#define CALLOC(t, n) ((t *) xcalloc (sizeof (t) * (n)))
#define MALLOC(t, n) ((t *) xmalloc (sizeof (t) * (n)))
@@ -364,7 +365,8 @@
r += val; \
} while(0);
-unsigned jhash(unsigned const char *k, int length)
+unsigned int
+jhash(unsigned const char *k, int length)
{
unsigned int a, b, c;
@@ -408,12 +410,16 @@
return c;
}
+#define UINTSZ sizeof (unsigned int)
+
#ifdef WORDS_BIGENDIAN
/* The ifs are ordered from the first byte in memory to the last. */
-#define sum_up_to_nul(r, p, flag) \
+#define sum_up_to_nul(r, p, plen, flag) \
do { \
- unsigned int val; \
- memcpy(&val, (p), 4); \
+ unsigned int val = 0; \
+ size_t pn = (plen); \
+ size_t n = pn < UINTSZ ? pn : UINTSZ; \
+ memcpy (&val, (p), n); \
if ((val & 0xFF000000) == 0) \
flag = 1; \
else if ((val & 0xFF0000) == 0) \
@@ -427,51 +433,60 @@
/* First detect the presence of zeroes. If there is none, we can
sum the 4 bytes directly. Otherwise, the ifs are ordered as in the
big endian case, from the first byte in memory to the last. */
-#define sum_up_to_nul(r, p, flag) \
- do { \
- unsigned int val; \
- unsigned int zeroes; \
- memcpy(&val, (p), 4); \
- zeroes = ((val - 0x01010101) & ~val); \
- if (!(zeroes & 0x80808080)) \
- r += val; \
- else if ((val & 0xFF) == 0) \
- flag = 1; \
- else if ((val & 0xFF00) == 0) \
- r += val & 0xFF, flag = 1; \
- else if ((val & 0xFF0000) == 0) \
- r += val & 0xFFFF, flag = 1; \
- else \
- r += val, flag = 1; \
+#define sum_up_to_nul(r, p, plen, flag) \
+ do { \
+ unsigned int val = 0; \
+ size_t pn = (plen); \
+ size_t n = pn < UINTSZ ? pn : UINTSZ; \
+ memcpy (&val, (p), n); \
+ flag = ((val - 0x01010101) & ~val) & 0x80808080; \
+ if (!flag) \
+ r += val; \
+ else if (val & 0xFF) \
+ { \
+ if ((val & 0xFF00) == 0) \
+ r += val & 0xFF; \
+ else if ((val & 0xFF0000) == 0) \
+ r += val & 0xFFFF; \
+ else \
+ r += val; \
+ } \
} while (0)
#endif
-/* This function performs magic which is correct but causes ASAN heartburn
- when we pass in a global constant string (at least). */
-__attribute__((no_sanitize_address))
-unsigned jhash_string(unsigned const char *k)
+unsigned int
+jhash_string(unsigned const char *k)
{
unsigned int a, b, c;
unsigned int have_nul = 0;
unsigned const char *start = k;
+ size_t klen = strlen ((const char*)k);
/* Set up the internal state */
a = b = c = JHASH_INITVAL;
/* All but the last block: affect some 32 bits of (a,b,c) */
for (;;) {
- sum_up_to_nul(a, k, have_nul);
+ sum_up_to_nul(a, k, klen, have_nul);
if (have_nul)
break;
- k += 4;
- sum_up_to_nul(b, k, have_nul);
+ k += UINTSZ;
+ assert (klen >= UINTSZ);
+ klen -= UINTSZ;
+
+ sum_up_to_nul(b, k, klen, have_nul);
if (have_nul)
break;
- k += 4;
- sum_up_to_nul(c, k, have_nul);
+ k += UINTSZ;
+ assert (klen >= UINTSZ);
+ klen -= UINTSZ;
+
+ sum_up_to_nul(c, k, klen, have_nul);
if (have_nul)
break;
- k += 4;
+ k += UINTSZ;
+ assert (klen >= UINTSZ);
+ klen -= UINTSZ;
jhash_mix(a, b, c);
}
