Bug report here:
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2023q4/017332.html
This error probably has no practical effect since even if the hash
is wrong, it's only compared internally to other hashes computed using
the same code.
Understanding the error:
hash-questions.c:168:21: runtime error: left shift of 128 by 24 places
cannot be represented in type 'int'
requires a certain amount of c-lawyerliness. I think the problem is that
m[i] = data[j] << 24
promotes the unsigned char data array value to int before doing the shift and
then promotes the result to unsigned char to match the type of m[i].
What needs to happen is to cast the unsigned char to unsigned int
BEFORE the shift.
This patch does that with explicit casts.
Previously, hash_questions() would return a random hash
if the packet was malformed, and probably the hash of a previous
query. Now handle this as an error.
