Re: [PATCH] Yama: use atomic allocations when reporting

From: Kees Cook
Date: Wed May 04 2016 - 13:22:59 EST


On Wed, May 4, 2016 at 7:18 AM, Sasha Levin <sasha.levin@xxxxxxxxxx> wrote:
> Access reporting often happens from atomic contexes. Avoid
> lockups when allocating memory for command lines.
>
> Fixes: 8a56038c2ae ("Yama: consolidate error reporting")
> Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx>

Thanks for catching this! Applied.

-Kees

> ---
> security/yama/yama_lsm.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c
> index c19f6e5..9b756b1 100644
> --- a/security/yama/yama_lsm.c
> +++ b/security/yama/yama_lsm.c
> @@ -47,8 +47,8 @@ static void report_access(const char *access, struct task_struct *target,
> {
> char *target_cmd, *agent_cmd;
>
> - target_cmd = kstrdup_quotable_cmdline(target, GFP_KERNEL);
> - agent_cmd = kstrdup_quotable_cmdline(agent, GFP_KERNEL);
> + target_cmd = kstrdup_quotable_cmdline(target, GFP_ATOMIC);
> + agent_cmd = kstrdup_quotable_cmdline(agent, GFP_ATOMIC);
>
> pr_notice_ratelimited(
> "ptrace %s of \"%s\"[%d] was attempted by \"%s\"[%d]\n",
> --
> 1.9.1
>



--
Kees Cook
Chrome OS & Brillo Security