Horton

Avoid overflow with simplehash

Ranier Vilela <ranier.vf@gmail.com>

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From: Ranier Vilela <ranier.vf@gmail.com>
To: Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2023-07-06T14:28:18Z
Lists: pgsql-hackers

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Hi,

SimpleHash.

The function SH_START_ITERATE can trigger some overflow.

See:
typedef struct SH_ITERATOR
{
uint32 cur; /* current element */
uint32 end;
bool done; /* iterator exhausted? */
} SH_ITERATOR;

The cur field is uint32 size and currently can be stored a uint64,
which obviously does not fit.

Also, the current index is int, which is possibly insufficient
since items can be up to uint32.

Attached a fix.

best regards,
Ranier Vilela

Commits

  1. Fix type of iterator variable in SH_START_ITERATE