[MEDIUM] Handle long lines properly
Currently, there is a hidden line length limit in the haproxy, set
to 256-1 chars. With large acls (for example many hdr(host) matches)
it may be not enough and which is even worse, error message may
be totally confusing as everything above this limit is treated
as a next line:
echo -ne "frontend aqq 1.2.3.4:80\nmode http\nacl e hdr(host) -i X X X X X X X www.xx.example.com stats\n"|
sed s/X/www.some-host-name.example.com/g > ha.cfg && haproxy -c -f ./ha.cfg
[WARNING] 300/163906 (11342) : parsing [./ha.cfg:4] : 'stats' ignored because frontend 'aqq' has no backend capability.
Recently I hit simmilar problem and it took me a while to find why
requests for "stats" are not handled properly.
This patch:
- makes the limit configurable (LINESIZE)
- increases default line length limit from 256 to 2048
- increases MAX_LINE_ARGS from 40 to 64
- fixes hidden assignment in fgets()
- moves arg/end/args/line inside the loop, making code auditing easier
- adds a check that shows error if the limit is reached
- changes "*line++ = 0;" to "*line++ = '\0';" (cosmetics)
With this patch, when LINESIZE is defined to 256, above example produces:
[ALERT] 300/164724 (27364) : parsing [/tmp/ha.cfg:3]: line too long, limit: 255.
[ALERT] 300/164724 (27364) : Error reading configuration file : /tmp/ha.cfg
diff --git a/include/common/defaults.h b/include/common/defaults.h
index 5b18767..1a69f40 100644
--- a/include/common/defaults.h
+++ b/include/common/defaults.h
@@ -43,8 +43,13 @@
#define REQURI_LEN 1024
#define CAPTURE_LEN 64
+// maximum line size when parsing config
+#ifndef LINESIZE
+#define LINESIZE 2048
+#endif
+
// max # args on a configuration line
-#define MAX_LINE_ARGS 40
+#define MAX_LINE_ARGS 64
// max # of added headers per request
#define MAX_NEWHDR 10
diff --git a/src/cfgparse.c b/src/cfgparse.c
index 6fcf09f..e347cff 100644
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -2305,13 +2305,9 @@
*/
int readcfgfile(const char *file)
{
- char thisline[256];
- char *line;
+ char thisline[LINESIZE];
FILE *f;
int linenum = 0;
- char *end;
- char *args[MAX_LINE_ARGS + 1];
- int arg;
int cfgerr = 0;
int confsect = CFG_NONE;
@@ -2323,11 +2319,25 @@
init_default_instance();
- while (fgets(line = thisline, sizeof(thisline), f) != NULL) {
+ while (fgets(thisline, sizeof(thisline), f) != NULL) {
+ int arg;
+ char *end;
+ char *args[MAX_LINE_ARGS + 1];
+ char *line = thisline;
+
linenum++;
end = line + strlen(line);
+ if (end-line == sizeof(thisline)-1 && *(end-1) != '\n') {
+ /* Check if we reached the limit and the last char is not \n.
+ * Watch out for the last line without the terminating '\n'!
+ */
+ Alert("parsing [%s:%d]: line too long, limit: %d.\n",
+ file, linenum, sizeof(thisline)-1);
+ return -1;
+ }
+
/* skip leading spaces */
while (isspace((unsigned char)*line))
line++;
@@ -2385,7 +2395,7 @@
}
else if (isspace((unsigned char)*line)) {
/* a non-escaped space is an argument separator */
- *line++ = 0;
+ *line++ = '\0';
while (isspace((unsigned char)*line))
line++;
args[++arg] = line;