Bash-5.3 patch 11: fix mapfile problem when callback unsets the variable it is modifying

builtins/mapfile.def

@@ -153,9 +153,7 @@ mapfile (int fd, long line_count_goal, long origin, long nskip, long callback_qu
   line_length = 0;
   unbuffered_read = 0;
 
-  /* The following check should be done before reading any lines.  Doing it
-     here allows us to call bind_array_element instead of bind_array_variable
-     and skip the variable lookup on every call. */
+  /* The following check should be done before reading any lines. */
   entry = builtin_find_indexed_array (array_name, flags & MAPF_CLEARARRAY);
   if (entry == 0)
     return EXECUTION_FAILURE;
@@ -201,8 +199,13 @@ mapfile (int fd, long line_count_goal, long origin, long nskip, long callback_qu
 	  run_callback (callback, array_index, line);
 	}
 
-      /* XXX - bad things can happen if the callback modifies ENTRY, e.g.,
-	 unsetting it or changing it to a non-indexed-array type. */
+      /* Bad things can happen if the callback modifies ENTRY, e.g.,
+	 unsetting it or changing it to a non-indexed-array type, so we
+	 look it up again every time we need to assign something */
+      entry = bind_array_variable (array_name, array_index, line, 0);
+      if (entry == 0 || ASSIGN_DISALLOWED (entry, 0))
+	return EXECUTION_FAILURE;
+
       bind_array_element (entry, array_index, line, 0);
 
       /* Have we exceeded # of lines to store? */

patchlevel.h

@@ -25,6 +25,6 @@
    regexp `^#define[ 	]*PATCHLEVEL', since that's what support/mkversion.sh
    looks for to find the patch level (for the sccs version string). */
 
-#define PATCHLEVEL 10
+#define PATCHLEVEL 11
 
 #endif /* _PATCHLEVEL_H_ */