cgroup: fix an off-by-one bug which may trigger BUG_ON()
authorLi Zefan <lizefan@huawei.com>
Tue, 12 Mar 2013 22:36:00 +0000 (15:36 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 8 May 2013 02:51:56 +0000 (19:51 -0700)
commit97630ecdbda8138baf35a66b6e59dee940da05e1
tree455d48c2c0f99103af12d4790c88d52626a63990
parentb593b4dc6442a5fd8a569fdbcc8cb5fa2609d1b1
cgroup: fix an off-by-one bug which may trigger BUG_ON()

commit 3ac1707a13a3da9cfc8f242a15b2fae6df2c5f88 upstream.

The 3rd parameter of flex_array_prealloc() is the number of elements,
not the index of the last element.

The effect of the bug is, when opening cgroup.procs, a flex array will
be allocated and all elements of the array is allocated with
GFP_KERNEL flag, but the last one is GFP_ATOMIC, and if we fail to
allocate memory for it, it'll trigger a BUG_ON().

Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernel/cgroup.c