The patch titled
     register_memory/unregister_memory: fix use-after-free and refcounting
has been removed from the -mm tree.  Its filename was
     register_memory-unregister_memory-fix-use-after-free-and-refcounting.patch

This patch was dropped because it was merged into mainline or a subsystem tree

The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/

------------------------------------------------------
Subject: register_memory/unregister_memory: fix use-after-free and refcounting
From: Badari Pulavarty <[EMAIL PROTECTED]>

register_memory()/unregister_memory() never gets called with "root". 
unregister_memory() is accessing kobject_name of the object just freed up. 
Since no one uses the code, lets take the code out.  And also, make
register_memory() static.

Another bug fix - before calling unregister_memory() remove_memory_block()
gets a ref on kobject.  unregister_memory() need to drop that ref before
calling sysdev_unregister().

Signed-off-by: Badari Pulavarty <[EMAIL PROTECTED]>
Cc: Kay Sievers <[EMAIL PROTECTED]>
Cc: Greg Kroah-Hartman <[EMAIL PROTECTED]>
Cc: Yasunori Goto <[EMAIL PROTECTED]>
Cc: Andy Whitcroft <[EMAIL PROTECTED]>
Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
---

 drivers/base/memory.c |   22 +++++++---------------
 1 file changed, 7 insertions(+), 15 deletions(-)

diff -puN 
drivers/base/memory.c~register_memory-unregister_memory-fix-use-after-free-and-refcounting
 drivers/base/memory.c
--- 
a/drivers/base/memory.c~register_memory-unregister_memory-fix-use-after-free-and-refcounting
+++ a/drivers/base/memory.c
@@ -62,8 +62,8 @@ void unregister_memory_notifier(struct n
 /*
  * register_memory - Setup a sysfs device for a memory block
  */
-int register_memory(struct memory_block *memory, struct mem_section *section,
-               struct node *root)
+static
+int register_memory(struct memory_block *memory, struct mem_section *section)
 {
        int error;
 
@@ -71,26 +71,18 @@ int register_memory(struct memory_block 
        memory->sysdev.id = __section_nr(section);
 
        error = sysdev_register(&memory->sysdev);
-
-       if (root && !error)
-               error = sysfs_create_link(&root->sysdev.kobj,
-                                         &memory->sysdev.kobj,
-                                         kobject_name(&memory->sysdev.kobj));
-
        return error;
 }
 
 static void
-unregister_memory(struct memory_block *memory, struct mem_section *section,
-               struct node *root)
+unregister_memory(struct memory_block *memory, struct mem_section *section)
 {
        BUG_ON(memory->sysdev.cls != &memory_sysdev_class);
        BUG_ON(memory->sysdev.id != __section_nr(section));
 
+       /* drop the ref. we got in remove_memory_block() */
+       kobject_put(&memory->sysdev.kobj);
        sysdev_unregister(&memory->sysdev);
-       if (root)
-               sysfs_remove_link(&root->sysdev.kobj,
-                                 kobject_name(&memory->sysdev.kobj));
 }
 
 /*
@@ -345,7 +337,7 @@ static int add_memory_block(unsigned lon
        mutex_init(&mem->state_mutex);
        mem->phys_device = phys_device;
 
-       ret = register_memory(mem, section, NULL);
+       ret = register_memory(mem, section);
        if (!ret)
                ret = mem_create_simple_file(mem, phys_index);
        if (!ret)
@@ -396,7 +388,7 @@ int remove_memory_block(unsigned long no
        mem_remove_simple_file(mem, phys_index);
        mem_remove_simple_file(mem, state);
        mem_remove_simple_file(mem, phys_device);
-       unregister_memory(mem, section, NULL);
+       unregister_memory(mem, section);
 
        return 0;
 }
_

Patches currently in -mm which might be from [EMAIL PROTECTED] are

fix-invalidate_inode_pages2_range-to-not-clear-ret.patch
memory-hotplug-add-removable-to-sysfs-to-show-memblock-removability.patch
fs-aioc-make-3-functions-static.patch

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