registry/internal/api/handlers/v0/list_errors.go
Radoslav Dimitrov fecef4f9ed
fix: don't leak internal error detail in GET /v0/servers 500 response (#1338)
## Summary
Fixes the information-disclosure regression introduced by #1335 (item 1
of #1337).

`ListServersError` passed the raw `err` into
`huma.Error500InternalServerError(...)`. huma serializes extra error
args into the response body's `errors` array (`ErrorModel.Errors`,
`json:"errors,omitempty"`), so on the **public, unauthenticated** `GET
/v0/servers` endpoint a genuine DB failure echoed the internal wrapped
error from `internal/database/postgres.go` (`error iterating rows: <pgx
error>`) back to the client. pgx/pgconn errors can carry SQLSTATE codes,
constraint/table/column names, and internal messages (CWE-209).

## Change
- Drop `err` from the 500 call so only the generic message is returned;
keep `log.Printf` for the server-side detail — matching the sibling
handlers (`servers.go:190/220`, `edit.go`, `status.go`).
- Add a regression test
(`TestListServersError_realFailureDoesNotLeakDetail`) that marshals the
500 error and asserts the internal detail is absent from the
client-visible body. Existing tests only asserted status codes, which is
why the leak slipped through.

The 499 client-cancelled path is unchanged (the client has already
disconnected, so nothing is leaked there).

## Test plan
- [x] `go test ./internal/api/handlers/v0/... -run ListServersError`
(3/3 pass)
- [x] `go build ./...`, `go vet`, `golangci-lint` (no new findings in
changed files)

## Note
This leaves the non-security items in #1337 (correcting the `superfluous
WriteHeader` claim, `statusClientClosed` const reuse, broader
cancellation-guard scope) for separate follow-up. Closing #1337 here
since the only security-impacting item is addressed; reopen/split if
you'd prefer to track the nits independently.

Closes #1337

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-05 03:08:33 -04:00

24 lines
751 B
Go

package v0
import (
"context"
"errors"
"log"
"github.com/danielgtaylor/huma/v2"
)
// ListServersError maps ListServers failures; client disconnects must not log as 500s.
func ListServersError(ctx context.Context, err error) error {
if err == nil {
return nil
}
if errors.Is(err, context.Canceled) || errors.Is(ctx.Err(), context.Canceled) {
return huma.NewError(499, "Client closed request", err)
}
log.Printf("list servers failed: %v", err)
// Do not pass err here: huma serializes extra error args into the response
// body, which would leak internal (e.g. pgx) error detail to clients. Log it
// server-side only, like the sibling handlers in servers.go.
return huma.Error500InternalServerError("Failed to get registry list")
}