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Subject: Re: [PATCH 5.12] mt76: fix potential DMA mapping leak
To:     Kalle Valo <kvalo@codeaurora.org>
Cc:     linux-wireless@vger.kernel.org, greearb@candelatech.com
References: <20210323214737.53254-1-nbd@nbd.name>
 <20210411084750.380F5C43461@smtp.codeaurora.org>
From:   Felix Fietkau <nbd@nbd.name>
Message-ID: <3766ead5-944d-6feb-e897-f7b59b9c5f11@nbd.name>
Date:   Sun, 11 Apr 2021 12:25:09 +0200
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On 2021-04-11 10:47, Kalle Valo wrote:
> Felix Fietkau <nbd@nbd.name> wrote:
> 
>> With buf uninitialized in mt76_dma_tx_queue_skb_raw, its field skip_unmap
>> could potentially inherit a non-zero value from stack garbage.
>> If this happens, it will cause DMA mappings for MCU command frames to not be
>> unmapped after completion
>> 
>> Fixes: 27d5c528a7ca ("mt76: fix double DMA unmap of the first buffer on 7615/7915")
>> Cc: stable@vger.kernel.org
>> Signed-off-by: Felix Fietkau <nbd@nbd.name>
> 
> Sorry, I missed this and I suspect it's now too late for v5.12. Felix, can you
> instead take this to your tree so that we can get this to v5.13? I assigned
> this to you on patchwork.
Will do. I plan on sending an updated pull request today.

- Felix