If bufsize overflows we will have an infinite loop. In practice
this will not happen unless we have made a coding error. Add an
INSIST to detect this condition.
181retry:
182 isc_buffer_allocate(mctx, &b, bufsize);
183 result = dns_rdata_totext(rdata, NULL, b);
184 if (result == ISC_R_NOSPACE) {
185 isc_buffer_free(&b);
CID 498031: (#1 of 1): Overflowed constant (INTEGER_OVERFLOW)
overflow_const: Expression bufsize, which is equal to 0, overflows
the type that receives it, an unsigned integer 32 bits wide.
186 bufsize *= 2;
187 goto retry;
188 }
(cherry picked from commit 20ac13fb23)
0dbda6661d