Hans Leidekker : wpcap: Call GetAdaptersAddresses() in a loop.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 80d629acbd13c160de5af1cd48960265f54de00d
URL:    https://gitlab.winehq.org/wine/wine/-/commit/80d629acbd13c160de5af1cd4896026...

Author: Hans Leidekker <hans(a)codeweavers.com>
Date:   Mon Sep  4 18:07:24 2023 +0200

wpcap: Call GetAdaptersAddresses() in a loop.

---

 dlls/wpcap/wpcap.c | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/dlls/wpcap/wpcap.c b/dlls/wpcap/wpcap.c
index f96e7098ae5..b96e940c024 100644
--- a/dlls/wpcap/wpcap.c
+++ b/dlls/wpcap/wpcap.c
@@ -391,18 +391,21 @@ static void free_devices( struct pcap_interface *devs )
 
 static IP_ADAPTER_ADDRESSES *get_adapters( void )
 {
-    DWORD size = 0;
-    IP_ADAPTER_ADDRESSES *ret;
+    ULONG err, size = 4096;
+    IP_ADAPTER_ADDRESSES *tmp, *ret;
     ULONG flags = GAA_FLAG_SKIP_ANYCAST | GAA_FLAG_SKIP_MULTICAST | GAA_FLAG_SKIP_DNS_SERVER;
 
-    if (GetAdaptersAddresses( AF_UNSPEC, flags, NULL, NULL, &size ) != ERROR_BUFFER_OVERFLOW) return NULL;
     if (!(ret = malloc( size ))) return NULL;
-    if (GetAdaptersAddresses( AF_UNSPEC, flags, NULL, ret, &size ))
+    err = GetAdaptersAddresses( AF_UNSPEC, flags, NULL, ret, &size );
+    while (err == ERROR_BUFFER_OVERFLOW)
     {
-        free( ret );
-        return NULL;
+        if (!(tmp = realloc( ret, size ))) break;
+        ret = tmp;
+        err = GetAdaptersAddresses( AF_UNSPEC, flags, NULL, ret, &size );
     }
-    return ret;
+    if (err == ERROR_SUCCESS) return ret;
+    free( ret );
+    return NULL;
 }
 
 static IP_ADAPTER_ADDRESSES *find_adapter( IP_ADAPTER_ADDRESSES *list, const char *name )