commit fbeaf87b54479383a77dc1fc41318bb788267154
from: Omar Polo <op@omarpolo.com>
date: Sun May 22 18:55:41 2022 UTC

fail on "jumbo" requests (except for Twrite)

except for Twrite, all other requests are passed via a single imsg.
We don't handle "jumbo" request for anything outside Twrite, nor it
does make sense actually, so let's drop it.

(well, for Twstat an argument can be made, maybe)

commit - 182b48dc821a0a4cf7bbcfcdf5f9d376136fd7e6
commit + fbeaf87b54479383a77dc1fc41318bb788267154
blob - 46b1580bded14c39a8f459de78093768df1ec8b5
blob + 40c9054fac901264fe7318860cfcf86e61265e3d
--- kamid/client.c
+++ kamid/client.c
@@ -41,6 +41,11 @@
 #include "log.h"
 #include "sandbox.h"
 #include "utils.h"
+
+/*
+ * Max message size aviable via a single imsg.
+ */
+#define IMSG_MAXSIZE (MAX_IMSGSIZE - IMSG_HEADER_SIZE)
 
 /*
  * The minimum value allowed for the msize.
@@ -1974,6 +1979,13 @@ handle_message(struct imsg *imsg, size_t len, int cont
 		writetag = hdr.tag;
 		twrite(&hdr, data, len, &writefid, &writepos, &writeleft,
 		    &writeskip);
+		return;
+	}
+
+	if (len > IMSG_MAXSIZE) {
+		log_warnx("can't handle message: too long for its type");
+		client_send_listener(IMSG_CLOSE, NULL, 0);
+		client_shutdown();
 		return;
 	}