From f6f5b137446a77deb2e943fc9778cd523f0beb2f Mon Sep 17 00:00:00 2001
From: Benjamin Valentin <benjamin.valentin@ml-pa.com>
Date: Tue, 2 May 2023 15:02:56 +0200
Subject: [PATCH] nanocoap_sock: don't use return buffer for request

---
 sys/net/application_layer/nanocoap/sock.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/sys/net/application_layer/nanocoap/sock.c b/sys/net/application_layer/nanocoap/sock.c
index dccef29c7582..7eec11f1d36a 100644
--- a/sys/net/application_layer/nanocoap/sock.c
+++ b/sys/net/application_layer/nanocoap/sock.c
@@ -369,9 +369,12 @@ static int _get_put_cb(void *arg, coap_pkt_t *pkt)
 
 ssize_t nanocoap_sock_get(nanocoap_sock_t *sock, const char *path, void *buf, size_t len)
 {
-    uint8_t *pktpos = buf;
+    /* buffer for CoAP header */
+    uint8_t buffer[CONFIG_NANOCOAP_BLOCK_HEADER_MAX];
+    uint8_t *pktpos = buffer;
+
     coap_pkt_t pkt = {
-        .hdr = buf,
+        .hdr = (void *)pktpos,
     };
 
     struct iovec ctx = {