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Subject: Re: [PATCH v3] bus: mhi: core: Sanity check values from remote device
 before use
To:     Jeffrey Hugo <jhugo@codeaurora.org>,
        manivannan.sadhasivam@linaro.org
Cc:     bbhatt@codeaurora.org, linux-arm-msm@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <1615411855-15053-1-git-send-email-jhugo@codeaurora.org>
From:   Hemant Kumar <hemantk@codeaurora.org>
Message-ID: <dda17db8-d2f4-bf9c-1ac0-1bcd35262b7d@codeaurora.org>
Date:   Wed, 7 Apr 2021 14:30:17 -0700
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On 3/10/21 1:30 PM, Jeffrey Hugo wrote:
> When parsing the structures in the shared memory, there are values which
> come from the remote device.  For example, a transfer completion event
> will have a pointer to the tre in the relevant channel's transfer ring.
> As another example, event ring elements may specify a channel in which
> the event occurred, however the specified channel value may not be valid
> as no channel is defined at that index even though the index may be less
> than the maximum allowed index.  Such values should be considered to be
> untrusted, and validated before use.  If we blindly use such values, we
> may access invalid data or crash if the values are corrupted.
> 
> If validation fails, drop the relevant event.
> 
> Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>

Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
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