[BUG] check: http-check expect + regex would crash in defaults section
Manoj Kumar reported a case where haproxy would crash upon start-up. The
cause was an "http-check expect" statement declared in the defaults section,
which caused a NULL regex to be used during the check. This statement is not
allowed in defaults sections precisely because this requires saving a copy
of the regex in the default proxy. But the check was not made to prevent it
from being declared there, hence the issue.
Instead of adding code to detect its abnormal use, we decided to implement
it. It was not that much complex because the expect_str part was not used
with regexes, so it could hold the string form of the regex in order to
compile it again for every backend (there's no way to clone regexes).
This patch has been tested and works. So it's both a bugfix and a minor
feature enhancement.
It should be backported to 1.4 though it's not critical since the config
was not supposed to be supported.
diff --git a/include/types/proxy.h b/include/types/proxy.h
index e4fcc77..da64bb1 100644
--- a/include/types/proxy.h
+++ b/include/types/proxy.h
@@ -316,7 +316,7 @@
int grace; /* grace time after stop request */
char *check_req; /* HTTP or SSL request to use for PR_O_HTTP_CHK|PR_O_SSL3_CHK */
int check_len; /* Length of the HTTP or SSL3 request */
- char *expect_str; /* http-check expected content */
+ char *expect_str; /* http-check expected content : string or text version of the regex */
regex_t *expect_regex; /* http-check expected content */
struct chunk errmsg[HTTP_ERR_SIZE]; /* default or customized error messages for known errors */
int uuid; /* universally unique proxy ID, used for SNMP */