Workaround for https://crbug.com/988025.

--- src/lib/crypto/krb/prng.c
+++ src/lib/crypto/krb/prng.c
@@ -102,6 +102,11 @@ k5_get_os_entropy(unsigned char *buf, size_t len, int strong)
 #if defined(__linux__) && defined(SYS_getrandom)
     int r;
 
+    // https://crbug.com/988025: Workaround for uninitialized memory errors
+    // under MSAN. Memory sanitizer does not track memory writes by
+    // SYS_getrandom calls.
+    memset(buf, 0, len);
+
     while (len > 0) {
         /*
          * Pull from the /dev/urandom pool, but require it to have been seeded.