postgres-github.git / summary / log / commit / refs

commit    43451a7a2b3305571e7f8ed56d053e97acca1d1d
Author:   Tom Lane <tgl@sss.pgh.pa.us>
Commit:   Noah Misch <noah@leadboat.com>
Date:     Mon May 11 12:13:46 2026 +0000

    Guard against overflow in "left" fields of query_int and ltxtquery.
    
    contrib/intarray's query_int type uses an int16 field to hold the
    offset from a binary operator node to its left operand.  However, it
    allows the number of nodes to be as much as will fit in MaxAllocSize,
    so there is a risk of overflowing int16 depending on the precise shape
    of the tree.  Simple right-associative cases like "a | b | c | ..."
    work fine, so we should not solve this by restricting the overall
    number of nodes.  Instead add a direct test of whether each individual
    offset is too large.
    
    contrib/ltree's ltxtquery type uses essentially the same logic and
    has the same 16-bit restriction.
    
    (The core backend's tsquery.c has a variant of this logic too, but
    in that case the target field is 32 bits, so it is okay so long
    as varlena datums are restricted to 1GB.)
    
    In v16 and up, these types support soft error reporting, so we have
    to complicate the recursive findoprnd function's API a bit to allow
    the complaint to be reported softly.  v14/v15 don't need that.
    
    Undocumented and overcomplicated code like this makes my head hurt,
    so add some comments and simplify while at it.
    
    Reported-by: Xint Code
    Author: Tom Lane <tgl@sss.pgh.pa.us>
    Reviewed-by: Michael Paquier <michael@paquier.xyz>
    Backpatch-through: 14
    Security: CVE-2026-6473

[parent: b63f25bddfeb]