diff options
| author | Li Zefan <lizefan@huawei.com> | 2013-03-12 15:36:00 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-05-07 19:51:56 -0700 |
| commit | 97630ecdbda8138baf35a66b6e59dee940da05e1 (patch) | |
| tree | 455d48c2c0f99103af12d4790c88d52626a63990 | |
| parent | b593b4dc6442a5fd8a569fdbcc8cb5fa2609d1b1 (diff) | |
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>
| -rw-r--r-- | kernel/cgroup.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index a4c47d1b3ce..4eb1ed3e5be 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -2020,7 +2020,7 @@ static int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader) if (!group) return -ENOMEM; /* pre-allocate to guarantee space while iterating in rcu read-side. */ - retval = flex_array_prealloc(group, 0, group_size - 1, GFP_KERNEL); + retval = flex_array_prealloc(group, 0, group_size, GFP_KERNEL); if (retval) goto out_free_group_list; |