jyapayne/musl
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

fix spurious overflows in strtoull with small bases

Browse source 
whenever the base was small enough that more than one digit could
still fit after UINTMAX_MAX/36-1 was reached, only the first would be
allowed; subsequent digits would trigger spurious overflow, making it
impossible to read the largest values in low bases.
This commit is contained in:
Rich Felker 2012-04-13 03:26:59 -04:00
commit 54222d1efc
1 changed files with 3 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

10
src/internal/intparse.c
View file

@ -25,12 +25,12 @@ static const unsigned char digits[] = {
};
#define SLIM (UINT_MAX/36-1)
#define LLIM (UINTMAX_MAX/36-1)
int __intparse(struct intparse *v, const void *buf, size_t n)
{
const unsigned char *s = buf;
int d, b = v->base;
uintmax_t llim;
v->cnt += n;
for (; n; n--, s++) switch (v->state) {
@ -83,16 +83,12 @@ int __intparse(struct intparse *v, const void *buf, size_t n)
v->state++;
v->val = v->small;
case 5:
for (; n && (d=digits[*s])<b && v->val<=LLIM; n--, s++)
llim = UINTMAX_MAX/b;
for (; n && (d=digits[*s])<b && v->val<=llim && d<=UINTMAX_MAX-v->val*b; n--, s++)
v->val = v->val * b + d;
if (!n) return 1;
if (d >= b) goto finished;
if (v->val <= (UINTMAX_MAX-d)/b)
v->val = v->val * b + d;
else
v->err = ERANGE;
v->state++;
n--; s++;
case 6:
if (n && digits[*s]<b) {
v->err = ERANGE;