Coverity: mt7915_mcu_get_chan_mib_info(): Memory - illegal accesses - coverity-bot

From: coverity-bot <keescook@chromium.org>
To: Bo Jiao <Bo.Jiao@mediatek.com>
Cc: Lorenzo Bianconi <lorenzo@kernel.org>,
	linux-wireless@vger.kernel.org, Jakub Kicinski <kuba@kernel.org>,
	Kalle Valo <kvalo@kernel.org>,
	Matthias Brugger <matthias.bgg@gmail.com>,
	Shayne Chen <shayne.chen@mediatek.com>,
	Eric Dumazet <edumazet@google.com>,
	linux-arm-kernel@lists.infradead.org, netdev@vger.kernel.org,
	linux-mediatek@lists.infradead.org, Felix Fietkau <nbd@nbd.name>,
	"David S. Miller" <davem@davemloft.net>,
	linux-kernel@vger.kernel.org, Paolo Abeni <pabeni@redhat.com>,
	Sean Wang <sean.wang@mediatek.com>,
	MeiChia Chiu <MeiChia.Chiu@mediatek.com>,
	Ryder Lee <ryder.lee@mediatek.com>,
	Sujuan Chen <sujuan.chen@mediatek.com>,
	Bo Jiao <bo.jiao@mediatek.com>,
	"Gustavo A. R. Silva" <gustavo@embeddedor.com>,
	linux-next@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Coverity: mt7915_mcu_get_chan_mib_info(): Memory - illegal accesses
Date: Fri, 2 Dec 2022 14:24:30 -0800	[thread overview]
Message-ID: <202212021424.34C0F695E4@keescook> (raw)

Hello!

This is an experimental semi-automated report about issues detected by
Coverity from a scan of next-20221202 as part of the linux-next scan project:
https://scan.coverity.com/projects/linux-next-weekly-scan

You're getting this email because you were associated with the identified
lines of code (noted below) that were touched by commits:

  Thu Feb 3 13:57:56 2022 +0100
    417a4534d223 ("mt76: mt7915: update mt7915_chan_mib_offs for mt7916")

Coverity reported the following:

*** CID 1527801:  Memory - illegal accesses  (OVERRUN)
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c:3005 in mt7915_mcu_get_chan_mib_info()
2999     		start = 5;
3000     		ofs = 0;
3001     	}
3002
3003     	for (i = 0; i < 5; i++) {
3004     		req[i].band = cpu_to_le32(phy->mt76->band_idx);
vvv     CID 1527801:  Memory - illegal accesses  (OVERRUN)
vvv     Overrunning array "offs" of 9 4-byte elements at element index 9 (byte offset 39) using index "i + start" (which evaluates to 9).
3005     		req[i].offs = cpu_to_le32(offs[i + start]);
3006
3007     		if (!is_mt7915(&dev->mt76) && i == 3)
3008     			break;
3009     	}
3010

If this is a false positive, please let us know so we can mark it as
such, or teach the Coverity rules to be smarter. If not, please make
sure fixes get into linux-next. :) For patches fixing this, please
include these lines (but double-check the "Fixes" first):

Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 1527801 ("Memory - illegal accesses")
Fixes: 417a4534d223 ("mt76: mt7915: update mt7915_chan_mib_offs for mt7916")

Thanks for your attention!

-- 
Coverity-bot