[hackers] [quark][PATCH] Fix strftime error handling

From: robert <robertrussell.72001_AT_gmail.com>
Date: Fri, 8 Jul 2022 11:12:17 -0700

Unlike snprintf, strftime buffer contents are undefined when it fails,
so make sure the buffer is null-terminated. To prevent garbage from
being printed out, we simply set the timestamp to the empty string, but
maybe setting it to "unknown time" or something similar would be better.
Either way, I don't think this can fail until year 10000, so it's not a
big deal.

---
 connection.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/connection.c b/connection.c
index 8aca2ab..24de809 100644
--- a/connection.c
+++ b/connection.c
_AT_@ -31,7 +31,8 @@ connection_log(const struct connection *c)
 	if (!strftime(tstmp, sizeof(tstmp), "%Y-%m-%dT%H:%M:%SZ",
 	              gmtime(&(time_t){time(NULL)}))) {
 		warn("strftime: Exceeded buffer capacity");
-		/* continue anyway (we accept the truncation) */
+		tstmp[0] = '\0'; /* tstmp contents are undefined on failure */
+		/* continue anyway */
 	}
 
 	/* generate address-string */
-- 
2.17.1

Received on Fri Jul 08 2022 - 20:12:17 CEST