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Date:   Thu, 21 Oct 2021 09:05:58 -0700
From:   Kees Cook <keescook@chromium.org>
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Oleg Nesterov <oleg@redhat.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        David Miller <davem@davemloft.net>, sparclinux@vger.kernel.org
Subject: Re: [PATCH 04/20] signal/sparc32: Remove unreachable do_exit in
 do_sparc_fault
Message-ID: <202110210905.8CA101674@keescook>
References: <87y26nmwkb.fsf@disp2133>
 <20211020174406.17889-4-ebiederm@xmission.com>
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On Wed, Oct 20, 2021 at 12:43:50PM -0500, Eric W. Biederman wrote:
> The call to do_exit in do_sparc_fault immediately follows a call to
> unhandled_fault.  The function unhandled_fault never returns.  This
> means the call to do_exit can never be reached.

Same thought: replace with unreachable() just to make this more
self-documenting? Either way:

Reviewed-by: Kees Cook <keescook@chromium.org>

> 
> Cc: David Miller <davem@davemloft.net>
> Cc: sparclinux@vger.kernel.org
> Fixes: 2.3.41
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
> ---
>  arch/sparc/mm/fault_32.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/arch/sparc/mm/fault_32.c b/arch/sparc/mm/fault_32.c
> index fa858626b85b..90dc4ae315c8 100644
> --- a/arch/sparc/mm/fault_32.c
> +++ b/arch/sparc/mm/fault_32.c
> @@ -248,7 +248,6 @@ asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write,
>  	}
>  
>  	unhandled_fault(address, tsk, regs);
> -	do_exit(SIGKILL);
>  
>  /*
>   * We ran out of memory, or some other thing happened to us that made
> -- 
> 2.20.1
> 

-- 
Kees Cook