50192: use set{u,g}id() for dropping privilege on NetBSD

ChangeLog

@@ -1,3 +1,8 @@
+2022-05-11  Jun-ichi Takimoto  <takimoto-j@kba.biglobe.ne.jp>
+
+	* 50192: Src/openssh_bsd_setres_id.c: use set{u,g}id() instead of
+	setre{u,g}id() for dropping privilege on NetBSD
+
 2022-05-08  dana  <dana@dana.is>
 
 	* 50176 (with xpufx, tweaked): Completion/Linux/Command/_htop:

Src/openssh_bsd_setres_id.c

@@ -55,6 +55,16 @@
 #include <unistd.h>
 #include <string.h>
 
+#ifdef __NetBSD__
+/*
+ * On NetBSD, setreuid() does not reset the saved uid if the real uid
+ * is not modified. Better to use setuid() that resets all of real,
+ * effective and saved uids to the specified value. Same for setregid().
+ */
+#define BROKEN_SETREUID
+#define BROKEN_SETREGID
+#endif
+
 #if defined(ZSH_IMPLEMENT_SETRESGID) || defined(BROKEN_SETRESGID)
 int
 setresgid(gid_t rgid, gid_t egid, gid_t sgid)