linux-kernel - Re: [PATCH] arm64: print additional fault message when executing non-exec memory

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20191028164150.GG5576@willie-the-truck>
Date:   Mon, 28 Oct 2019 16:41:51 +0000
From:   Will Deacon <will@...nel.org>
To:     Xiang Zheng <zhengxiang9@...wei.com>
Cc:     catalin.marinas@....com, james.morse@....com,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        wanghaibin.wang@...wei.com
Subject: Re: [PATCH] arm64: print additional fault message when executing
 non-exec memory

On Mon, Oct 28, 2019 at 05:08:37PM +0800, Xiang Zheng wrote:
> When attempting to executing non-executable memory, the fault message
> shows:
> 
>   Unable to handle kernel read from unreadable memory at virtual address
>   ffff802dac469000
> 
> This may confuse someone, so add a new fault message for instruction
> abort.
> 
> Signed-off-by: Xiang Zheng <zhengxiang9@...wei.com>
> ---
>  arch/arm64/mm/fault.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
> index 9fc6db0bcbad..68bf4ec376d0 100644
> --- a/arch/arm64/mm/fault.c
> +++ b/arch/arm64/mm/fault.c
> @@ -318,6 +318,8 @@ static void __do_kernel_fault(unsigned long addr, unsigned int esr,
>  	if (is_el1_permission_fault(addr, esr, regs)) {
>  		if (esr & ESR_ELx_WNR)
>  			msg = "write to read-only memory";
> +		else if (is_el1_instruction_abort(esr))
> +			msg = "execute non-executable memory";

nit, please make this "execute from non-executable memory".

With that:

Acked-by: Will Deacon <will@...nel.org>

Will