From: Tim Duesterhus <tim@bastelstu.be>
Date: Mon, 22 Jun 2020 20:57:45 +0000 (+0200)
Subject: MINOR: cfgparse: Warn on truncated lines / files
X-Git-Tag: v2.2-dev11~44
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=2fd5bdb439da29f15381aeb57c51327ba57674fc;p=thirdparty%2Fhaproxy.git

MINOR: cfgparse: Warn on truncated lines / files

As discussed on the list: https://www.mail-archive.com/haproxy@formilux.org/msg37698.html

This patch adds warnings to the configuration parser that detect the
following situations:

- A line being truncated by a null byte in the middle.
- A file not ending in a new line (and possibly being truncated).
---

diff --git a/src/cfgparse.c b/src/cfgparse.c
index 4ccca14d2b..257df05a1e 100644
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -1854,6 +1854,7 @@ int readcfgfile(const char *file)
 	size_t outlen = 0;
 	size_t outlinesize = 0;
 	int fatal = 0;
+	int missing_lf = -1;
 
 	if ((thisline = malloc(sizeof(*thisline) * linesize)) == NULL) {
 		ha_alert("parsing [%s] : out of memory.\n", file);
@@ -1872,6 +1873,14 @@ next_line:
 		char *args[MAX_LINE_ARGS + 1];
 		char *line = thisline;
 
+		if (missing_lf != -1) {
+			ha_warning("parsing [%s:%d]: Stray NUL character at position %d. "
+			           "This will become a hard error in HAProxy 2.3.\n",
+			           file, linenum, (missing_lf + 1));
+			err_code |= ERR_WARN;
+			missing_lf = -1;
+		}
+
 		linenum++;
 
 		if (fatal >= 50) {
@@ -1909,6 +1918,10 @@ next_line:
 			/* kill trailing LF */
 			*(end - 1) = 0;
 		}
+		else {
+			/* mark this line as truncated */
+			missing_lf = end - line;
+		}
 
 		/* skip leading spaces */
 		while (isspace((unsigned char)*line))
@@ -2058,6 +2071,13 @@ next_line:
 		}
 	}
 
+	if (missing_lf != -1) {
+		ha_warning("parsing [%s:%d]: Missing LF on last line, file might have been truncated at position %d. "
+		           "This will become a hard error in HAProxy 2.3.\n",
+		           file, linenum, (missing_lf + 1));
+		err_code |= ERR_WARN;
+	}
+
 	if (cs && cs->post_section_parser)
 		err_code |= cs->post_section_parser();