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Date:   Thu, 20 Oct 2022 21:12:57 +0800
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Subject: Re: [PATCH v3 0/1] vsprintf: check non-canonical pointer by
 kern_addr_valid()
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To:     Jane Chu <jane.chu@oracle.com>, <pmladek@suse.com>,
        <rostedt@goodmis.org>, <senozhatsky@chromium.org>,
        <andriy.shevchenko@linux.intel.com>, <linux@rasmusvillemoes.dk>,
        <linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>
CC:     <konrad.wilk@oracle.com>, <haakon.bugge@oracle.com>,
        <john.haxby@oracle.com>
References: <20221019193431.2923462-1-jane.chu@oracle.com>
From:   Kefeng Wang <wangkefeng.wang@huawei.com>
In-Reply-To: <20221019193431.2923462-1-jane.chu@oracle.com>
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On 2022/10/20 3:34, Jane Chu wrote:
> Changes since v2 [1]:
>   - revised commit comment for clarification;
>   - cc linux-mm for expert's review on the kern_addr_valid() usage as suggested by Petr;

but this won't fix issue on archs which don't have correct 
kern_addr_valid(), right?

could we call copy_from_kernel_nofault() when it could works well, and 
skip it on early boot?

other options, call some functions in include/asm-generic/sections.h  or 
include/linux/kallsyms.h?


>   - cc Kefeng Wang in light of his recent patch [2]
>
> [1]: https://lore.kernel.org/lkml/288a7aba-c647-b51f-bdb3-99a62449dbb3@oracle.com/T/
> [2]: https://lore.kernel.org/lkml/20221018074014.185687-1-wangkefeng.wang@huawei.com/
>
> Jane Chu (1):
>    vsprintf: protect kernel from panic due to non-canonical pointer
>      dereference
>
>   lib/vsprintf.c | 3 +++
>   1 file changed, 3 insertions(+)
>