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Date:   Sun, 23 Jan 2022 16:55:51 +0300
From:   Alexey Dobriyan <adobriyan@gmail.com>
To:     Hao Lee <haolee.swjtu@gmail.com>
Cc:     akpm@linux-foundation.org, christian.brauner@ubuntu.com,
        keescook@chromium.org, jamorris@linux.microsoft.com,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] proc: use kmalloc instead of __get_free_page() to alloc
 path buffer
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References: <20220123100837.GA1491@haolee.io>
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On Sun, Jan 23, 2022 at 10:08:37AM +0000, Hao Lee wrote:
> It's not a standard approach that use __get_free_page() to alloc path
> buffer directly. We'd better use kmalloc and PATH_MAX.

> --- a/fs/proc/base.c
> +++ b/fs/proc/base.c
> @@ -1764,25 +1764,26 @@ static const char *proc_pid_get_link(struct dentry *dentry,
>  
>  static int do_proc_readlink(struct path *path, char __user *buffer, int buflen)
>  {
> -	char *tmp = (char *)__get_free_page(GFP_KERNEL);
> +	char *buf = NULL;

I'd rather not rename anything but keep it minimal.