The following path will cause array out of bound.
memblock_add_region() will always set nid in memblock.reserved to
MAX_NUMNODES. In numa_register_memblks(), after we set all nid to
correct valus in memblock.reserved, we called setup_node_data(), and
used memblock_alloc_nid() to allocate memory, with nid set to
MAX_NUMNODES.
The nodemask_t type can be seen as a bit array. And the index is 0 ~
MAX_NUMNODES-1.
After that, when we call node_set() in numa_clear_kernel_node_hotplug(),
the nodemask_t got an index of value MAX_NUMNODES, which is out of [0 ~
MAX_NUMNODES-1].
See below:
numa_init()
|---> numa_register_memblks()
| |---> memblock_set_node(memory) set correct nid in memblock.memory
| |---> memblock_set_node(reserved) set correct nid in memblock.reserved
| |......
| |---> setup_node_data()
| |---> memblock_alloc_nid() here, nid is set to MAX_NUMNODES (1024)
|......
|---> numa_clear_kernel_node_hotplug()
|---> node_set() here, we have an index 1024, and overflowed
This patch moves nid setting to numa_clear_kernel_node_hotplug() to fix
this problem.
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Tested-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Reported-by: Dave Jones <davej@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Tested-by: Dave Jones <davej@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
7bc35fdde6