Prevent signed integer overflow.
MODIFY
mrbgems/mruby-sprintf/src/sprintf.c
mrbgems/mruby-sprintf/src/sprintf.c
@@ -200,7 +200,7 @@ check_name_arg(mrb_state *mrb, int posarg, const char *name, mrb_int len)
#define GETNUM(n, val) \
for (; p < end && ISDIGIT(*p); p++) {\
- if (n > MRB_INT_MAX/10) {\
+ if (n > (MRB_INT_MAX - (*p - '0'))/10) {\
mrb_raise(mrb, E_ARGUMENT_ERROR, #val " too big"); \
} \
n = 10 * n + (*p - '0'); \
@@ -1056,18 +1056,18 @@ retry:
if (i > 0)
need = BIT_DIGITS(i);
}
- need += (flags&FPREC) ? prec : 6;
- if (need < 0) {
+ if (need > MRB_INT_MAX - ((flags&FPREC) ? prec : 6)) {
too_big_width:
mrb_raise(mrb, E_ARGUMENT_ERROR,
(width > prec ? "width too big" : "prec too big"));
}
+ need += (flags&FPREC) ? prec : 6;
if ((flags&FWIDTH) && need < width)
need = width;
- need += 20;
- if (need <= 0) {
+ if (need > MRB_INT_MAX - 20) {
goto too_big_width;
}
+ need += 20;
CHECK(need);
n = snprintf(&buf[blen], need, fbuf, fval);

Prevent signed integer overflow.