pgsql: Be more wary about constant's datatype in scalarineqsel(). - Mailing list pgsql-committers

From Noah Misch
Subject pgsql: Be more wary about constant's datatype in scalarineqsel().
Date
Msg-id E1wtQFl-00000000y3M-3Ljp@gemulon.postgresql.org
Whole thread
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Be more wary about constant's datatype in scalarineqsel().

The special case here for estimating conditions involving a ctid
column failed to check that the RHS constant is of type tid.
While that'd always be true for the built-in operators that
reference this selectivity estimator, a maliciously constructed
operator could provide a user-controlled Datum value that would
get interpreted as an ItemPointer pointer.  That at least risks
SIGSEGV, and perhaps with a bit of sweat it could be used for
server memory disclosure.

Reported-by: Hcamael <baiyjrh@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Noah Misch <noah@leadboat.com>
Backpatch-through: 14
Security: CVE-2026-14668

Branch
------
REL_19_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/0d60ee71727ccd71a791b088a91c4bd8c1fb85e4
Author: Tom Lane <tgl@sss.pgh.pa.us>

Modified Files
--------------
src/backend/utils/adt/selfuncs.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)


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