Re: glibc qsort() vulnerability

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>

To: Mats Kindahl <mats@timescale.com>

Cc: pgsql-hackers@lists.postgresql.org

Date: 2024-02-06T15:11:16Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Use new overflow-safe integer comparison functions.
- 3b42bdb47169 17.0 landed
Introduce overflow-safe integer comparison functions.
- 6b80394781c8 17.0 landed
Replace calls to pg_qsort() with the qsort() macro.
- 5497daf3aa2a 17.0 landed
Switch over to using our own qsort() all the time, as has been proposed
- 6edd2b4a91bd 8.2.0 cited

Mats Kindahl <mats@timescale.com> writes:
> There is a bug in glibc's qsort() algorithm that runs the risk of creating
> an out-of-bounds error if the comparison function is not transitive, for
> example, if subtraction is used so that it can create an overflow.

We don't use glibc's qsort.  Have you checked whether there's a
problem with the code we do use?

			regards, tom lane