umputun / reproxy / 25721950550

79%

Build Type

push

github

Committed by web-flow

Commit Message

fix(proxy): bound RoundRobinSelector return to current n (#250) (#251)

* fix(proxy): bound RoundRobinSelector return to current n

When alive-backend count shrinks between calls (e.g. health-check flips
a backend dead), the previously stored lastSelected could exceed the new
n. The returned index was the un-bounded stale value, causing matchHandler
to index out of range and panic.

Apply modulo before returning, so Select is always in [0, n) regardless
of how lastSelected was set on a prior call. Adds regression test that
reproduces the panic with shrinking n.

Related to #250

* chore: address lint cleanups (atomic.Int32, gosec G710)

Replace int32+sync/atomic free functions with atomic.Int32 type in
test files (modernize/atomictypes lint), and suppress gosec G710 on
the http->https redirect handler with explanation - redirect target
is derived from the request host, matching the standard upgrade
pattern.

* fix: address Copilot review on PR #251

Apply modulo on lastSelected write to keep [0, n) invariant - matches
original code's wrap-to-0 semantics when n changes, while still bounding
the returned value to current n. Both forms fix the panic; this one has
smaller behavioral delta from pre-fix code.

Add TestRoundRobinSelector_SelectGrowingN that pins the wrap behavior
when n grows back (e.g., dead backend recovers), catching regression
to the non-modulo write.

Expand the //nolint:gosec comment on the http->https redirect to spell
out the threat model (Host header is browser-set from URL hostname,
so a foreign Host can't be injected into a victim's request).

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5 of 5 new or added lines in 2 files covered. (100.0%)

2 existing lines in 1 file now uncovered.

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