1 files changed, 5 insertions, 1 deletions

diff --git a/src/lib/libcrypto/err/err.c b/src/lib/libcrypto/err/err.c
index 403fcd4607..2eca16d77c 100644
--- a/src/lib/libcrypto/err/err.c
+++ b/src/lib/libcrypto/err/err.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: err.c,v 1.50 2022/12/26 07:18:52 jmc Exp $ */
+/* $OpenBSD: err.c,v 1.51 2023/03/27 09:15:45 jan Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -580,6 +580,7 @@ build_SYS_str_reasons(void)
         static char strerror_tab[NUM_SYS_STR_REASONS][LEN_SYS_STR_REASON];
         int i;
         static int init = 1;
+        int save_errno;
 
         CRYPTO_r_lock(CRYPTO_LOCK_ERR);
         if (!init) {
@@ -594,6 +595,8 @@ build_SYS_str_reasons(void)
                 return;
         }
 
+        /* strerror(3) will set errno to EINVAL when i is an unknown errno. */
+        save_errno = errno;
         for (i = 1; i <= NUM_SYS_STR_REASONS; i++) {
                 ERR_STRING_DATA *str = &SYS_str_reasons[i - 1];
 
@@ -610,6 +613,7 @@ build_SYS_str_reasons(void)
                 if (str->string == NULL)
                         str->string = "unknown";
         }
+        errno = save_errno;
 
         /* Now we still have SYS_str_reasons[NUM_SYS_STR_REASONS] = {0, NULL},
          * as required by ERR_load_strings. */