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Message-ID: <8b72ce47-c338-2061-f11a-c0a608686d8c@linaro.org>
Date:   Fri, 11 Aug 2023 09:42:55 +0100
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Subject: Re: [PATCH v2 4/4] venus: hfi_parser: Add check to keep the number of
 codecs within range
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To:     Vikash Garodia <quic_vgarodia@quicinc.com>,
        stanimir.k.varbanov@gmail.com, agross@kernel.org,
        andersson@kernel.org, konrad.dybcio@linaro.org, mchehab@kernel.org,
        hans.verkuil@cisco.com, tfiga@chromium.org
Cc:     linux-media@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org
References: <1691634304-2158-1-git-send-email-quic_vgarodia@quicinc.com>
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 <fec4a8c7-206f-7af8-4ea9-c919a677bf7e@linaro.org>
 <2214c31b-eca2-012e-a100-21252a724e7c@quicinc.com>
From:   Bryan O'Donoghue <bryan.odonoghue@linaro.org>
In-Reply-To: <2214c31b-eca2-012e-a100-21252a724e7c@quicinc.com>
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On 11/08/2023 07:04, Vikash Garodia wrote:
> 
> On 8/10/2023 5:03 PM, Bryan O'Donoghue wrote:
>> On 10/08/2023 03:25, Vikash Garodia wrote:
>>> +    if (hweight_long(core->dec_codecs) + hweight_long(core->enc_codecs) >
>>> MAX_CODEC_NUM)
>>> +        return;
>>> +
>>
>> Shouldn't this be >= ?
> Not needed. Lets take a hypothetical case when core->dec_codecs has initial 16
> (0-15) bits set and core->enc_codecs has next 16 bits (16-31) set. The bit count
> would be 32. The codec loop after this check would run on caps array index 0-31.
> I do not see a possibility for OOB access in this case.
> 
>>
>> struct hfi_plat_caps caps[MAX_CODEC_NUM];
>>
>> ---
>> bod
>>

Are you not doing a general defensive coding pass in this series ie

"[PATCH v2 2/4] venus: hfi: fix the check to handle session buffer 
requirement"

---
bod