Steps to reproduce:

* Build with `integer` sanitizer
* Start: `UBSAN_OPTIONS="suppressions=$(pwd)/test/sanitizer_suppressions/ubsan:print_stacktrace=1:halt_on_error=1:report_error_type=1" ./src/qt/bitcoin-qt -chain=main`
* Enter `getdescriptorinfo "sh(multi(1,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,[00000000]xprv9uPDJpEQgRQfDcW7BkF7eTya6RPxXeJCqCJGHuCJ4GiRVLzkTXBAJMu2qaMWPrS7AANYqdq6vcBcBUdJCVVFceUvJFjaPdGZ2y9WACViL4L/58)0)"` into the console
return 0;
    }
    seckey += 3;
    
    if (end - seckey < 2 || seckey[0] != 0x04u) {
        return 0;
    }
    ptrdiff_t oslen = seckey[1];
    seckey += 2;
    if (oslen > 32 || end - seckey < oslen) {
        return 0;
    }
    memcpy(out32 + (32 - oslen), seckey, oslen);
    if (!secp256k1_ec_seckey_verify(ctx, out32)) {
        memset(out32, 0, 32);
        return 0;
    }
    return 1;
}
/**
 * This serializes to a DER encoding of the ECPrivateKey type from section C.4 of SEC 1
 * <https://www.secg.org/sec1-v2.pdf>. The optional parameters and publicKey fields are
 * included.
 *
 * seckey must point to an output buffer of length at least CKey::SIZE bytes.
 * seckeylen must initially be set to the size of the seckey buffer. Upon return it
 * will be set to the number of bytes used in the buffer.
 * key32 must point to a 32-byte raw private key.
 */
int ec_seckey_export_der(const secp256k1_context *ctx, unsigned char *seckey, size_t *seckeylen, const unsigned char *key32, bool compressed) {