From b36c181bfc0d75f461c892782259c2c2acc29394 Mon Sep 17 00:00:00 2001
From: Simo Sorce <simo@redhat.com>
Date: Mar 23 2020 20:18:19 +0000
Subject: Use getrandom() for random numbers


Although this place id not cryptgraphically relevant, there is no point
in not using a proper random value. This happens only once so it is not
a performance issue.

Signed-off-by: Simo Sorce <simo@redhat.com>

---

diff --git a/src/client/gpm_common.c b/src/client/gpm_common.c
index 808f350..60b1fdc 100644
--- a/src/client/gpm_common.c
+++ b/src/client/gpm_common.c
@@ -9,6 +9,7 @@
 #include <pthread.h>
 #include <sys/epoll.h>
 #include <fcntl.h>
+#include <sys/random.h>
 #include <sys/timerfd.h>
 
 #define FRAGMENT_BIT (1 << 31)
@@ -41,7 +42,9 @@ pthread_once_t gpm_init_once_control = PTHREAD_ONCE_INIT;
 static void gpm_init_once(void)
 {
     pthread_mutexattr_t attr;
-    unsigned int seedp;
+    char *buf = (char *)&gpm_global_ctx.next_xid;
+    size_t len = sizeof(gpm_global_ctx.next_xid);
+    size_t ret = 0;
 
     pthread_mutexattr_init(&attr);
     pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
@@ -52,8 +55,9 @@ static void gpm_init_once(void)
     gpm_global_ctx.epollfd = -1;
     gpm_global_ctx.timerfd = -1;
 
-    seedp = time(NULL) + getpid() + pthread_self();
-    gpm_global_ctx.next_xid = rand_r(&seedp);
+    while(ret < len) {
+        ret += getrandom(buf + ret, len - ret, 0);
+    }
 
     pthread_mutexattr_destroy(&attr);