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Message-ID: <a04c7754-e807-9b5c-8565-e92ab513af94@quicinc.com>
Date:   Fri, 3 Nov 2023 08:54:47 -0600
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Subject: Re: [PATCH v2] bus: mhi: host: Add alignment check for event ring
 read pointer
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To:     Krishna chaitanya chundru <quic_krichai@quicinc.com>,
        "Manivannan Sadhasivam" <mani@kernel.org>
CC:     <mhi@lists.linux.dev>, <linux-arm-msm@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <quic_vbadigan@quicinc.com>,
        <quic_ramkri@quicinc.com>, <quic_skananth@quicinc.com>,
        <quic_parass@quicinc.com>, <stable@vger.kernel.org>
References: <20231031-alignment_check-v2-1-1441db7c5efd@quicinc.com>
From:   Jeffrey Hugo <quic_jhugo@quicinc.com>
In-Reply-To: <20231031-alignment_check-v2-1-1441db7c5efd@quicinc.com>
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On 10/31/2023 3:51 AM, Krishna chaitanya chundru wrote:
> Though we do check the event ring read pointer by "is_valid_ring_ptr"
> to make sure it is in the buffer range, but there is another risk the
> pointer may be not aligned.  Since we are expecting event ring elements
> are 128 bits(struct mhi_ring_element) aligned, an unaligned read pointer
> could lead to multiple issues like DoS or ring buffer memory corruption.
> 
> So add a alignment check for event ring read pointer.
> 
> Fixes: ec32332df764 ("bus: mhi: core: Sanity check values from remote device before use")
> cc: stable@vger.kernel.org
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>

Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>