On 13/02/17 13:16, hyc(a)symas.com wrote:
> datacount > UINT_MAX is truncated to unsigned int:
> data.mv_size = 0x100000002 puts 2 items.
> datacount * datasize can exceed UINT_MAX, which mdb_page_spill()
> truncates to unsigned int. Such a massive put() will likely
> fail anyway, but it should at least try to spill properly first.
We should probably check if mv_size is greater than UINT_MAX and return
EINVAL. (Or ERANGE.)
If you mean check for overflow, that doesn't work on 32-bit hosts.
We can do a general overflow check (assuming dcount i size_t here)
xdata.mv_size = data.mv_size * dcount;
if (xdata.mv_size / dcount != data.mv_size)
or if you want a compile-time max safe dcount on 32-bit, that's
EVEN((size_t)-1 / (MAX_PAGESIZE/MDB_MINKEYS))
So - MDB_BAD_VALSIZE or a new MDB_* code:
Not EINVAL, that should be reserved for obvious error conditions.
And not ERANGE, we should not add new errno.h codes.