Alertmanager: reject global mattermost_webhook_url_file - #7768
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Alertmanager: reject global mattermost_webhook_url_file#7768friedrichg wants to merge 2 commits into
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validateGlobalConfig checks ten global *_file settings but omitted MattermostWebhookURLFile, the only one missing. This was not exploitable. When a mattermost receiver is present, upstream copies the global value into the receiver's WebhookURLFile during unmarshal (config.go:637), which happens inside config.Load and therefore before validateAlertmanagerConfig runs, so validateMattermostConfig already rejected it. With no mattermost receiver the global value was accepted but never propagated, and nothing read it. The coverage was accidental though: it depends entirely on upstream doing that propagation in UnmarshalYAML. If that ever moves into the notifier constructor the check silently stops working. Validate the field directly so the guarantee does not rest on upstream ordering. Reuse the existing error and extend its message to name both settings, matching how slack_api_url_file, rocketchat_token_file and the other dual-scope settings are reported. Signed-off-by: Friedrich Gonzalez <1517449+friedrichg@users.noreply.github.com>
Signed-off-by: Friedrich Gonzalez <1517449+friedrichg@users.noreply.github.com>
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What this PR does: Adds
mattermost_webhook_url_fileto the global*_filechecks invalidateGlobalConfig, the only one of the eleven that was missing.Not exploitable today. When a mattermost receiver is present, upstream copies the global value into the receiver's
WebhookURLFileduring unmarshal, which runs before validation, so the per-receiver check already rejected it. With no mattermost receiver the value was accepted but never read.The coverage was accidental though, resting entirely on upstream doing that propagation in
UnmarshalYAML. Validating the field directly means the guarantee no longer depends on upstream ordering.Reuses the existing error and extends its message to name both settings, matching how the other dual-scope settings are reported.
Found while auditing every file-path field reachable from a tenant config; the other 42 are all rejected.
CHANGELOG entry needs a PR number.