Changeset 4680ef5 in mainline

Timestamp:

2007-06-13T21:36:59Z (18 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

8b243f2

Parents:

341140c

Message:

Fix a double-free recently introduced in revision r2436.
Add a comment clarifying the life-cycle of the kernel_uarg structure.

Comment out the freeing of userspace thread stack while still running on it.
This should be fixed by implementing userspace version of thread_join().

Files:

• kernel/generic/src/proc/thread.c (modified) (2 diffs)
• uspace/libc/generic/thread.c (modified) (1 diff)

kernel/generic/src/proc/thread.c

@@ -386 +386 @@
                 task_destroy(t->task);
         
-        /*
-         * If the thread had a userspace context, free up its kernel_uarg
-         * structure.
-         */
-        if (t->flags & THREAD_FLAG_USPACE) {
-                ASSERT(t->thread_arg);
-                free(t->thread_arg);
-        }
-
         slab_free(thread_slab, t);
 }
@@ -683 +674 @@
                 return (unative_t) rc;
 
-        kernel_uarg = (uspace_arg_t *) malloc(sizeof(uspace_arg_t), 0); 
+        /*
+         * In case of failure, kernel_uarg will be deallocated in this function.
+         * In case of success, kernel_uarg will be freed in uinit().
+         */
+        kernel_uarg = (uspace_arg_t *) malloc(sizeof(uspace_arg_t), 0);
+        
         rc = copy_from_uspace(kernel_uarg, uspace_uarg, sizeof(uspace_arg_t));
         if (rc != 0) {

uspace/libc/generic/thread.c

@@ -108 +108 @@
         uarg->uspace_thread_function(uarg->uspace_thread_arg);
         /* XXX: we cannot free the userspace stack while running on it */
-        free(uarg->uspace_stack);
-        free(uarg);
+//      free(uarg->uspace_stack);
+//      free(uarg);
 
         /* If there is a manager, destroy it */