pgrepr: Fix i16 overflow panic decoding binary numeric#37070
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ggevay merged 1 commit intoJun 16, 2026
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The `numeric` binary wire header (ndigits/weight/sign/dscale) is read as i16 straight from the client's Bind parameter, and the scale was computed in i16: `(units - weight - 1) * 4`. A user-controlled `weight` of i16::MIN overflows this, panicking (and, with overflow-checks, aborting) the pgwire connection task -- a remote, post-auth, single-message DoS. Compute the scale in i32 (the i16 wire fields cannot overflow it) and explicitly reject headers whose implied scale exceeds the decode context's precision, returning a clean INVALID_PARAMETER_VALUE instead of panicking. Adds a pgtest regression test (numeric-binary-overflow.pt) plus param_formats/binary_values support in the pgtest harness to drive binary-format parameters. SQL-385 Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
aljoscha
approved these changes
Jun 16, 2026
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Fixes SQL-385
The
numericbinary wire header (ndigits/weight/sign/dscale) is read as i16 straight from the client's Bind parameter, and the scale was computed in i16:(units - weight - 1) * 4. An user-controlledweightof i16::MIN overflows this, panicking (and, with overflow-checks, aborting) the pgwire connection task -- a remote, post-auth, single-message DoS.Compute the scale in i32 (the i16 wire fields cannot overflow it) and explicitly reject headers whose implied scale exceeds the decode context's precision, returning a clean INVALID_PARAMETER_VALUE instead of panicking.
Adds a pgtest regression test (numeric-binary-overflow.pt) plus param_formats/binary_values support in the pgtest harness to drive binary-format parameters.