Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932184AbcDZX5V (ORCPT ); Tue, 26 Apr 2016 19:57:21 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:40247 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754101AbcDZXOI (ORCPT ); Tue, 26 Apr 2016 19:14:08 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Arnd Bergmann" , "David S. Miller" Date: Wed, 27 Apr 2016 01:02:21 +0200 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 103/217] ath9k: fix buffer overrun for ar9287 In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8426:ae4:c500:9cba:69ae:962d:6167 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2777 Lines: 67 3.16.35-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Arnd Bergmann commit 83d6f1f15f8cce844b0a131cbc63e444620e48b5 upstream. Code that was added back in 2.6.38 has an obvious overflow when accessing a static array, and at the time it was added only a code comment was put in front of it as a reminder to have it reviewed properly. This has not happened, but gcc-6 now points to the specific overflow: drivers/net/wireless/ath/ath9k/eeprom.c: In function 'ath9k_hw_get_gain_boundaries_pdadcs': drivers/net/wireless/ath/ath9k/eeprom.c:483:44: error: array subscript is above array bounds [-Werror=array-bounds] maxPwrT4[i] = data_9287[idxL].pwrPdg[i][4]; ~~~~~~~~~~~~~~~~~~~~~~~~~^~~ It turns out that the correct array length exists in the local 'intercepts' variable of this function, so we can just use that instead of hardcoding '4', so this patch changes all three instances to use that variable. The other two instances were already correct, but it's more consistent this way. Signed-off-by: Arnd Bergmann Fixes: 940cd2c12ebf ("ath9k_hw: merge the ar9287 version of ath9k_hw_get_gain_boundaries_pdadcs") Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- drivers/net/wireless/ath/ath9k/eeprom.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) --- a/drivers/net/wireless/ath/ath9k/eeprom.c +++ b/drivers/net/wireless/ath/ath9k/eeprom.c @@ -408,10 +408,9 @@ void ath9k_hw_get_gain_boundaries_pdadcs if (match) { if (AR_SREV_9287(ah)) { - /* FIXME: array overrun? */ for (i = 0; i < numXpdGains; i++) { minPwrT4[i] = data_9287[idxL].pwrPdg[i][0]; - maxPwrT4[i] = data_9287[idxL].pwrPdg[i][4]; + maxPwrT4[i] = data_9287[idxL].pwrPdg[i][intercepts - 1]; ath9k_hw_fill_vpd_table(minPwrT4[i], maxPwrT4[i], data_9287[idxL].pwrPdg[i], data_9287[idxL].vpdPdg[i], @@ -421,7 +420,7 @@ void ath9k_hw_get_gain_boundaries_pdadcs } else if (eeprom_4k) { for (i = 0; i < numXpdGains; i++) { minPwrT4[i] = data_4k[idxL].pwrPdg[i][0]; - maxPwrT4[i] = data_4k[idxL].pwrPdg[i][4]; + maxPwrT4[i] = data_4k[idxL].pwrPdg[i][intercepts - 1]; ath9k_hw_fill_vpd_table(minPwrT4[i], maxPwrT4[i], data_4k[idxL].pwrPdg[i], data_4k[idxL].vpdPdg[i], @@ -431,7 +430,7 @@ void ath9k_hw_get_gain_boundaries_pdadcs } else { for (i = 0; i < numXpdGains; i++) { minPwrT4[i] = data_def[idxL].pwrPdg[i][0]; - maxPwrT4[i] = data_def[idxL].pwrPdg[i][4]; + maxPwrT4[i] = data_def[idxL].pwrPdg[i][intercepts - 1]; ath9k_hw_fill_vpd_table(minPwrT4[i], maxPwrT4[i], data_def[idxL].pwrPdg[i], data_def[idxL].vpdPdg[i],