BUG/MEDIUM: lua: the function txn_done() from action wrapper can crash

If an action wrapper stops the processing of the transaction
with a txn_done() function, the return code of the action is
"continue". So the continue can implies the processing of other
like adding headers. However, the HTTP content is flushed and
a segfault occurs.

This patchs add a flag indicating that the Lua code want to
stop the processing, ths flags is forwarded to the haproxy core,
and other actions are ignored.

Must be backported in 1.6

diff --git a/include/types/hlua.h b/include/types/hlua.h
index b22e03e7d8a496e161362a01d6fa48244f88a0c5..698786dd8d65320da52261022e0df91abfadb205 100644 (file)
--- a/include/types/hlua.h
+++ b/include/types/hlua.h
@@ -31,6 +31,7 @@ struct stream;
 #define HLUA_WAKEREQWR 0x00000008
 #define HLUA_EXIT      0x00000010
 #define HLUA_MUST_GC   0x00000020
+#define HLUA_STOP      0x00000040
 
 #define HLUA_F_AS_STRING    0x01
 #define HLUA_F_MAY_USE_HTTP 0x02

diff --git a/src/hlua.c b/src/hlua.c
index f9a317d65fa41c5f83d392bf04556a3f1636b660..5cbfcfef9e9200c3e94a7c8d9d91640b8c08e3f6 100644 (file)
--- a/src/hlua.c
+++ b/src/hlua.c
@@ -4810,10 +4810,12 @@ __LJMP static int hlua_txn_set_mark(lua_State *L)
 __LJMP static int hlua_txn_done(lua_State *L)
 {
        struct hlua_txn *htxn;
+       struct hlua *hlua;
        struct channel *ic, *oc;
 
        MAY_LJMP(check_args(L, 1, "close"));
        htxn = MAY_LJMP(hlua_checktxn(L, 1));
+       hlua = hlua_gethlua(L);
 
        /* If the flags NOTERM is set, we cannot terminate the http
         * session, so we just end the execution of the current
@@ -4857,6 +4859,7 @@ __LJMP static int hlua_txn_done(lua_State *L)
 
        ic->analysers = 0;
 
+       hlua->flags |= HLUA_STOP;
        WILL_LJMP(hlua_done(L));
        return 0;
 }
@@ -5555,6 +5558,8 @@ static enum act_return hlua_action(struct act_rule *rule, struct proxy *px,
        case HLUA_E_OK:
                if (!hlua_check_proto(s, dir))
                        return ACT_RET_ERR;
+               if (s->hlua.flags & HLUA_STOP)
+                       return ACT_RET_STOP;
                return ACT_RET_CONT;
 
        /* yield. */