Introduce minimum allowed major driver and nif versions on load

4 files changed, 36 insertions, 4 deletions

diff --git a/erts/emulator/beam/erl_bif_ddll.c b/erts/emulator/beam/erl_bif_ddll.c
index 1728b200f7..56cd2ba04f 100644
--- a/erts/emulator/beam/erl_bif_ddll.c
+++ b/erts/emulator/beam/erl_bif_ddll.c
@@ -1548,8 +1548,10 @@ static int do_load_driver_entry(DE_Handle *dh, char *path, char *name)
 
     switch (dp->extended_marker) {
     case ERL_DRV_EXTENDED_MARKER:
-	if (ERL_DRV_EXTENDED_MAJOR_VERSION != dp->major_version
-	    || ERL_DRV_EXTENDED_MINOR_VERSION < dp->minor_version) {
+	if (dp->major_version < ERL_DRV_MIN_REQUIRED_MAJOR_VERSION_ON_LOAD
+	    || (ERL_DRV_EXTENDED_MAJOR_VERSION < dp->major_version
+		|| (ERL_DRV_EXTENDED_MAJOR_VERSION == dp->major_version
+		    && ERL_DRV_EXTENDED_MINOR_VERSION < dp->minor_version))) {
 	    /* Incompatible driver version */
 	    res = ERL_DE_LOAD_ERROR_INCORRECT_VERSION;
 	    goto error;
diff --git a/erts/emulator/beam/erl_driver.h b/erts/emulator/beam/erl_driver.h
index 5517c26ba4..3ecb379326 100644
--- a/erts/emulator/beam/erl_driver.h
+++ b/erts/emulator/beam/erl_driver.h
@@ -136,6 +136,22 @@ typedef struct {
 #define ERL_DRV_EXTENDED_MINOR_VERSION	0
 
 /*
+ * The emulator will refuse to load a driver with a major version
+ * lower than ERL_DRV_MIN_REQUIRED_MAJOR_VERSION_ON_LOAD. The load
+ * may however fail if user have not removed use of deprecated
+ * symbols.
+ *
+ * The ERL_DRV_MIN_REQUIRED_MAJOR_VERSION_ON_LOAD have to allow
+ * loading of drivers built at least two major OTP releases
+ * ago.
+ *
+ * Bump of major version to 3 happened in OTP 17. That is, in
+ * OTP 19 we can increase ERL_DRV_MIN_REQUIRED_MAJOR_VERSION_ON_LOAD
+ * to 3.
+ */
+#define ERL_DRV_MIN_REQUIRED_MAJOR_VERSION_ON_LOAD 2
+
+/*
  * The emulator will refuse to load a driver with different major
  * version than the one used by the emulator.
  */
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index 40860e141c..063dba056e 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -2049,8 +2049,10 @@ BIF_RETTYPE load_nif_2(BIF_ALIST_2)
 	      (entry = erts_sys_ddll_call_nif_init(init_func)) == NULL)) {
 	ret = load_nif_error(BIF_P, bad_lib, "Library init-call unsuccessful");
     }
-    else if (entry->major != ERL_NIF_MAJOR_VERSION
-	     || entry->minor > ERL_NIF_MINOR_VERSION
+    else if (entry->major < ERL_NIF_MIN_REQUIRED_MAJOR_VERSION_ON_LOAD
+	     || (ERL_NIF_MAJOR_VERSION < entry->major
+		 || (ERL_NIF_MAJOR_VERSION == entry->major
+		     && ERL_NIF_MINOR_VERSION < entry->minor))
 	     || (entry->major==2 && entry->minor == 5)) { /* experimental maps */
 	
 	ret = load_nif_error(BIF_P, bad_lib, "Library version (%d.%d) not compatible (with %d.%d).",
diff --git a/erts/emulator/beam/erl_nif.h b/erts/emulator/beam/erl_nif.h
index c12ba4d554..5b93c2398e 100644
--- a/erts/emulator/beam/erl_nif.h
+++ b/erts/emulator/beam/erl_nif.h
@@ -46,6 +46,18 @@
 #define ERL_NIF_MAJOR_VERSION 2
 #define ERL_NIF_MINOR_VERSION 6
 
+/*
+ * The emulator will refuse to load a nif-lib with a major version
+ * lower than ERL_NIF_MIN_REQUIRED_MAJOR_VERSION_ON_LOAD. The load
+ * may however fail if user have not removed use of deprecated
+ * symbols.
+ *
+ * The ERL_NIF_MIN_REQUIRED_MAJOR_VERSION_ON_LOAD have to allow
+ * loading of nif-libs built at least two major OTP releases
+ * ago.
+ */
+#define ERL_NIF_MIN_REQUIRED_MAJOR_VERSION_ON_LOAD 2
+
 #include <stdlib.h>
 
 #ifdef SIZEOF_CHAR