linux-kernel - Re: [PATCH v7 4/4] treewide: Switch memcpy() users of 'task->comm' to a more safer implementation

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Message-ID: <aJoHhDIL6T0Zo-nB@black.igk.intel.com>
Date: Mon, 11 Aug 2025 17:08:52 +0200
From: Andy Shevchenko <andriy.shevchenko@...el.com>
To: Bhupesh <bhupesh@...lia.com>
Cc: akpm@...ux-foundation.org, kernel-dev@...lia.com,
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Subject: Re: [PATCH v7 4/4] treewide: Switch memcpy() users of 'task->comm'
 to a more safer implementation

On Mon, Aug 11, 2025 at 12:16:09PM +0530, Bhupesh wrote:
> As Linus mentioned in [1], currently we have several memcpy() use-cases
> which use 'current->comm' to copy the task name over to local copies.
> For an example:
> 
>  ...
>  char comm[TASK_COMM_LEN];
>  memcpy(comm, current->comm, TASK_COMM_LEN);
>  ...
> 
> These should be rather calling a wrappper like "get_task_array()",
> which is implemented as:
> 
>    static __always_inline void
>        __cstr_array_copy(char *dst,
>             const char *src, __kernel_size_t size)
>    {
>         memcpy(dst, src, size);
>         dst[size] = 0;
>    }
> 
>    #define get_task_array(dst,src) \
>       __cstr_array_copy(dst, src, __must_be_array(dst))
> 
> The relevant 'memcpy()' users were identified using the following search
> pattern:
>  $ git grep 'memcpy.*->comm\>'

> [1]. https://lore.kernel.org/all/CAHk-=wi5c=_-FBGo_88CowJd_F-Gi6Ud9d=TALm65ReN7YjrMw@mail.gmail.com/
> 
> Signed-off-by: Bhupesh <bhupesh@...lia.com>

Same suggestion, make it a Link tag.

-- 
With Best Regards,
Andy Shevchenko