fix excessive stack usage

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

diff --git a/cache.c b/cache.c
index 1cbe18f..89bd015 100644 (file)
--- a/cache.c
+++ b/cache.c
@@ -343,7 +343,7 @@ cache_dump_records(struct blob_buf *buf, const char *name)
 {
        struct cache_record *r, *q = avl_find_element(&records, name, r, avl);
        const char *txt;
-       char buffer[MAX_NAME_LEN];
+       char buffer[INET6_ADDRSTRLEN];
 
        if (!q)
                return;

diff --git a/service.c b/service.c
index 1cf50e3..30f4770 100644 (file)
--- a/service.c
+++ b/service.c
@@ -85,35 +85,28 @@ service_name(const char *domain)
 static void
 service_add_ptr(const char *host)
 {
-       unsigned char buffer[MAX_NAME_LEN];
-       int len = dn_comp(host, buffer, MAX_NAME_LEN, NULL, NULL);
+       int len = dn_comp(host, mdns_buf, sizeof(mdns_buf), NULL, NULL);
 
        if (len < 1)
                return;
 
-       dns_add_answer(TYPE_PTR, buffer, len);
+       dns_add_answer(TYPE_PTR, mdns_buf, len);
 }
 
 static void
 service_add_srv(struct service *s)
 {
-       unsigned char buffer[MAX_NAME_LEN];
-       struct dns_srv_data *sd;
+       struct dns_srv_data *sd = (struct dns_srv_data *) mdns_buf;
        char *host = service_name("local");
-       int len = dn_comp(host, buffer, MAX_NAME_LEN, NULL, NULL);
+       int len = sizeof(*sd);
 
-       if (len < 1)
-               return;
-
-       sd = calloc(1, len + sizeof(struct dns_srv_data));
-       if (!sd)
+       len += dn_comp(host, mdns_buf + len, sizeof(mdns_buf) - len, NULL, NULL);
+       if (len <= sizeof(*sd))
                return;
 
        sd->port = cpu_to_be16(s->port);
-       memcpy(&sd[1], buffer, len);
-       host = service_name(s->service);
-       dns_add_answer(TYPE_SRV, (uint8_t *) sd, len + sizeof(struct dns_srv_data));
-       free(sd);
+       dns_add_answer(TYPE_SRV, mdns_buf, len);
+       service_name(s->service);
 }
 
 #define TOUT_LOOKUP    60

diff --git a/ubus.c b/ubus.c
index efd6cb1..08b808d 100644 (file)
--- a/ubus.c
+++ b/ubus.c
@@ -20,6 +20,7 @@
 #include <libubox/avl.h>
 #include <libubox/uloop.h>
 
+#include "util.h"
 #include "ubus.h"
 #include "cache.h"
 #include "service.h"
@@ -51,10 +52,10 @@ mdns_browse(struct ubus_context *ctx, struct ubus_object *obj,
                struct blob_attr *msg)
 {
        struct cache_entry *s, *q;
-       char buffer[MAX_NAME_LEN];
+       char *buffer = (char *) mdns_buf;
        void *c1 = NULL, *c2;
 
-        blob_buf_init(&b, 0);
+       blob_buf_init(&b, 0);
        avl_for_each_element(&entries, s, avl) {
                char *local;
                if (*((char *) s->avl.key) != '_')
@@ -95,10 +96,10 @@ mdns_hosts(struct ubus_context *ctx, struct ubus_object *obj,
                struct blob_attr *msg)
 {
        struct cache_entry *s;
-       char buffer[MAX_NAME_LEN];
+       char *buffer = (char *) mdns_buf;
        void *c;
 
-        blob_buf_init(&b, 0);
+       blob_buf_init(&b, 0);
        avl_for_each_element(&entries, s, avl) {
                char *local;
                if (*((char *) s->avl.key) == '_')

diff --git a/util.c b/util.c
index 0c4a4ee..87db94c 100644 (file)
--- a/util.c
+++ b/util.c
@@ -33,6 +33,7 @@
 #include "dns.h"
 #include "util.h"
 
+uint8_t mdns_buf[MDNS_BUF_LEN];
 int debug = 0;
 
 static void

diff --git a/util.h b/util.h
index 947f851..140e1da 100644 (file)
--- a/util.h
+++ b/util.h
@@ -14,12 +14,17 @@
 #ifndef _UTIL_H__
 #define _UTIL_H__
 
+#include <stdint.h>
+
 #define DBG(level, fmt, ...) do { \
        if (debug >= level) \
                fprintf(stderr, "mdnsd: %s (%d): " fmt, __func__, __LINE__, ## __VA_ARGS__); \
        } while (0)
 
+#define MDNS_BUF_LEN   (8 * 1024)
+
 extern int debug;
+extern uint8_t mdns_buf[MDNS_BUF_LEN];
 
 void *memdup(const void *d, int l);