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Subject: Re: [PATCH] arm64/vdso: don't leak kernel addresses
To:     Matteo Croce <mcroce@redhat.com>,
        linux-arm-kernel@lists.infradead.org
Cc:     linux-kernel@vger.kernel.org,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>
References: <20190330184638.16219-1-mcroce@redhat.com>
From:   Mukesh Ojha <mojha@codeaurora.org>
Message-ID: <03d00567-2efb-a2e9-e771-bf3bf121a8fa@codeaurora.org>
Date:   Sun, 31 Mar 2019 01:10:54 +0530
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On 3/31/2019 12:16 AM, Matteo Croce wrote:
> Since commit ad67b74d2469d9b8 ("printk: hash addresses printed with %p"),
> two obfuscated kernel pointer are printed at every boot:
>
>      vdso: 2 pages (1 code @ (____ptrval____), 1 data @ (____ptrval____))
>
> Remove the addresses from the print, which turns into a more discrete:
>
>      vdso: 2 pages (1 code, 1 data)
>
> Fixes: ad67b74d2469d9b8 ("printk: hash addresses printed with %p")
> Signed-off-by: Matteo Croce <mcroce@redhat.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>

Cheers,
-Mukesh


> ---
>   arch/arm64/kernel/vdso.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
> index 2d419006ad43..fdfee0ef5bc5 100644
> --- a/arch/arm64/kernel/vdso.c
> +++ b/arch/arm64/kernel/vdso.c
> @@ -146,8 +146,8 @@ static int __init vdso_init(void)
>   	}
>   
>   	vdso_pages = (vdso_end - vdso_start) >> PAGE_SHIFT;
> -	pr_info("vdso: %ld pages (%ld code @ %p, %ld data @ %p)\n",
> -		vdso_pages + 1, vdso_pages, vdso_start, 1L, vdso_data);
> +	pr_info("vdso: %ld pages (%ld code, %ld data)\n",
> +		vdso_pages + 1, vdso_pages, 1L);
>   
>   	/* Allocate the vDSO pagelist, plus a page for the data. */
>   	vdso_pagelist = kcalloc(vdso_pages + 1, sizeof(struct page *),