1 files changed, 19 insertions, 28 deletions

diff --git a/erts/emulator/beam/io.c b/erts/emulator/beam/io.c
index 4f131c74de..38e403d91a 100644
--- a/erts/emulator/beam/io.c
+++ b/erts/emulator/beam/io.c
@@ -4884,10 +4884,24 @@ erts_port_control(Process* c_p,
 	ASSERT(!tmp_alloced);
 	if (*ebinp == HEADER_SUB_BIN)
 	    ebinp = binary_val(((ErlSubBin *) ebinp)->orig);
+
 	if (*ebinp != HEADER_PROC_BIN)
 	    copy = 1;
 	else {
-	    binp = ((ProcBin *) ebinp)->val;
+            ProcBin *pb = (ProcBin *) ebinp;
+            int offset = bufp - pb->val->orig_bytes;
+
+	    ASSERT(pb->val->orig_bytes <= bufp
+		   && bufp + size <= pb->val->orig_bytes + pb->val->orig_size);
+
+            if (pb->flags) {
+                erts_emasculate_writable_binary(pb);
+
+                /* The procbin may have been reallocated, so update bufp */
+                bufp = pb->val->orig_bytes + offset;
+            }
+
+	    binp = pb->val;
 	    ASSERT(bufp <= bufp + size);
 	    ASSERT(binp->orig_bytes <= bufp
 		   && bufp + size <= binp->orig_bytes + binp->orig_size);
@@ -6890,12 +6904,6 @@ ErlDrvSizeT driver_vec_to_buf(ErlIOVec *vec, char *buf, ErlDrvSizeT len)
     return (orig_len - len);
 }
 
-
-/*
- * - driver_alloc_binary() is thread safe (efile driver depend on it).
- * - driver_realloc_binary(), and driver_free_binary() are *not* thread safe.
- */
-
 /*
  * reference count on driver binaries...
  */
@@ -6938,26 +6946,15 @@ driver_alloc_binary(ErlDrvSizeT size)
     return Binary2ErlDrvBinary(bin);
 }
 
-/* Reallocate space hold by binary */
+/* Reallocate space held by binary */
 
 ErlDrvBinary* driver_realloc_binary(ErlDrvBinary* bin, ErlDrvSizeT size)
 {
     Binary* oldbin;
     Binary* newbin;
 
-    if (!bin) {
-	erts_dsprintf_buf_t *dsbufp = erts_create_logger_dsbuf();
-	erts_dsprintf(dsbufp,
-		      "Bad use of driver_realloc_binary(%p, %lu): "
-		      "called with ",
-		      bin, (unsigned long)size);
-	if (!bin) {
-	    erts_dsprintf(dsbufp, "NULL pointer as first argument");
-	}
-	erts_send_warning_to_logger_nogl(dsbufp);
-	if (!bin)
-	    return driver_alloc_binary(size);
-    }
+    if (!bin)
+	return driver_alloc_binary(size);
 
     oldbin = ErlDrvBinary2Binary(bin);
     newbin = (Binary *) erts_bin_realloc_fnf(oldbin, size);
@@ -6971,14 +6968,8 @@ ErlDrvBinary* driver_realloc_binary(ErlDrvBinary* bin, ErlDrvSizeT size)
 void driver_free_binary(ErlDrvBinary* dbin)
 {
     Binary *bin;
-    if (!dbin) {
-	erts_dsprintf_buf_t *dsbufp = erts_create_logger_dsbuf();
-	erts_dsprintf(dsbufp,
-		      "Bad use of driver_free_binary(%p): called with "
-		      "NULL pointer as argument", dbin);
-	erts_send_warning_to_logger_nogl(dsbufp);
+    if (!dbin)
 	return;
-    }
 
     bin = ErlDrvBinary2Binary(dbin);
     if (erts_refc_dectest(&bin->refc, 0) == 0)