From: John Conroy <john.conroy@interoptechnologies.com>
Date: Wed, 13 Jul 2016 21:03:11 +0000 (-0400)
Subject: Truncate strjoin arguments if > DATA_MAX_NAME_LEN
X-Git-Tag: collectd-5.7.0~85^2~1
X-Git-Url: https://git.octo.it/?a=commitdiff_plain;h=f7d1db6cc1bed058ca03747f5c6bdd07ce12be27;p=collectd.git

Truncate strjoin arguments if > DATA_MAX_NAME_LEN

If strjoin() runs out of buffer space when joining strings, use the
remainder of available space rather than skipping additional strings

Reworked return() to avoid extra strlen() call
---

diff --git a/src/daemon/common.c b/src/daemon/common.c
index 05b11990..d1d8bf15 100644
--- a/src/daemon/common.c
+++ b/src/daemon/common.c
@@ -366,10 +366,12 @@ int strjoin (char *buffer, size_t buffer_size,
 			ptr += sep_len;
 			avail -= sep_len;
 		}
+		if (avail == 0)
+			return (-1);
 
 		field_len = strlen (fields[i]);
 		if (avail < field_len)
-			return (-1);
+			field_len = avail;
 
 		memcpy (ptr, fields[i], field_len);
 		ptr += field_len;
@@ -377,7 +379,7 @@ int strjoin (char *buffer, size_t buffer_size,
 	}
 
 	assert (buffer[buffer_size - 1] == 0);
-	return ((int) strlen (buffer));
+	return ((int) ((buffer_size - 1) - avail));
 }
 
 int escape_string (char *buffer, size_t buffer_size)