Coverity: mt76x0_phy_get_target_power(): Memory - illegal accesses

Coverity: mt76x0_phy_get_target_power(): Memory - illegal accesses

[coverity-bot]

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 Dec 1 17:29:12 2022 +0100
    b376d96362d8 ("wifi: mt76: move mt76_rate_power from core to mt76x02 driver code")

Coverity reported the following:

*** CID 1527804:  Memory - illegal accesses  (OVERRUN)
drivers/net/wireless/mediatek/mt76/mt76x0/phy.c:645 in mt76x0_phy_get_target_power()
639     	case 4:
640     		/* vht rates */
641     		tx_rate = info[1] & 0xf;
642     		if (tx_rate > 9)
643     			return -EINVAL;
644
vvv     CID 1527804:  Memory - illegal accesses  (OVERRUN)
vvv     Overrunning array "dev->rate_power.vht" of 2 bytes at byte offset 9 using index "tx_rate" (which evaluates to 9).
645     		*target_power = cur_power + dev->rate_power.vht[tx_rate];
646     		*target_pa_power = mt76x0_phy_get_rf_pa_mode(dev, 1, tx_rate);
647     		break;
648     	default:
649     		/* ht rates */
650     		tx_rate = info[1] & 0x7f;

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: 1527804 ("Memory - illegal accesses")
Fixes: b376d96362d8 ("wifi: mt76: move mt76_rate_power from core to mt76x02 driver code")

Thanks for your attention!

-- 
Coverity-bot