[PATCH] Fix daemon crash on messages without From:/Sender: header - #13
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janmuennich wants to merge 1 commit into
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[PATCH] Fix daemon crash on messages without From:/Sender: header#13janmuennich wants to merge 1 commit into
janmuennich wants to merge 1 commit into
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eoh() falls back to hval="from" when no Sender: header is present, then unconditionally looks up self.__header[hval]. For messages carrying neither a From: nor a Sender: header (e.g. message-id=<>, common in spam and bounces), the "from" key is never populated by the header() callback, so the lookup raises KeyError inside the milter callback. When that KeyError unwinds across the pymilter/libmilter thread boundary it can corrupt the exception object's refcount and abort the interpreter (CPython _PyObject_Dump of a KeyError instance), taking the whole daemon down. Postfix then waits out the milter timeout (300s) and falls back to milter_default_action, leaving From-domain verification disabled until the daemon is restarted. Guard the lookup: when neither Sender: nor From: is present there is no domain to verify, so log and skip the message (Milter.CONTINUE), mirroring the existing empty-address skip path.
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eoh() falls back to hval="from" when no Sender: header is present, then unconditionally looks up self.__header[hval]. For messages carrying neither a From: nor a Sender: header (e.g. message-id=<>, common in spam and bounces), the "from" key is never populated by the header() callback, so the lookup raises KeyError inside the milter callback.
When that KeyError unwinds across the pymilter/libmilter thread boundary it can corrupt the exception object's refcount and abort the interpreter (CPython _PyObject_Dump of a KeyError instance), taking the whole daemon down. Postfix then waits out the milter timeout (300s) and falls back to milter_default_action, leaving From-domain verification disabled until the daemon is restarted.
Guard the lookup: when neither Sender: nor From: is present there is no domain to verify, so log and skip the message (Milter.CONTINUE), mirroring the existing empty-address skip path.