Segfault in HTCP CLR request on 64-bit

[Jason Noble]

I recently ran into an issue where Squid 2.7 would segfault trying to 
issue HTCP CLR requests.  I found the segfault only occurred on 64-bit 
machines.  While debugging, I found that the value of stuff.S.req_hdrs 
was not initialized but later, strlen was being called on it.  This 
seems to -- by chance -- not fail on 32 bit builds, but always segfaults 
on 64-bit.  The attached patch fixed the problem for me and it seems 
good programming practice to properly initialize pointers to prevent 
issues such as this.  As the htcpStuff struct is used in other places, I 
have concerns that other issues may be lurking as well, although I have 
yet to run into them.

Regards,
Jason
diff --git a/src/htcp.c b/src/htcp.c
index b262d0f..5cfe715 100644
--- a/src/htcp.c
+++ b/src/htcp.c
@@ -1265,6 +1265,7 @@ htcpClear(StoreEntry * e, const char *uri, request_t * req
     stuff.f1 = 0;
     stuff.response = 0;
     stuff.msg_id = ++msg_id_counter;
+    stuff.S.req_hdrs = 0;
     switch (reason) {
     case HTCP_CLR_INVALIDATION:
        stuff.reason = 1;