Return-path: Received: from mail-pa0-f47.google.com ([209.85.220.47]:35237 "EHLO mail-pa0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751975AbcHMAQL (ORCPT ); Fri, 12 Aug 2016 20:16:11 -0400 Received: by mail-pa0-f47.google.com with SMTP id i5so550559pat.2 for ; Fri, 12 Aug 2016 17:16:11 -0700 (PDT) From: Petri Gynther To: linux-wireless@vger.kernel.org Cc: kvalo@codeaurora.org, davem@davemloft.net, joe@perches.com, akarwar@marvell.com, Petri Gynther Subject: [PATCH] Modify is_zero_ether_addr() to handle byte-aligned addresses Date: Fri, 12 Aug 2016 17:15:30 -0700 Message-Id: <1471047330-8153-1-git-send-email-pgynther@google.com> (sfid-20160813_021614_638975_0567168A) Sender: linux-wireless-owner@vger.kernel.org List-ID: $ iwconfig mlan0 essid MySSID [ 36.930000] Path: /sbin/iwconfig [ 36.930000] CPU: 0 PID: 203 Comm: iwconfig Not tainted 4.7.0 #2 [ 36.940000] task: 866f83a0 ti: 866a6000 task.ti: 866a6000 [ 36.940000] [ECR ]: 0x00230400 => Misaligned r/w from 0x8677f403 [ 36.960000] [EFA ]: 0x8677f403 [ 36.960000] [BLINK ]: mwifiex_scan_networks+0x17a/0x198c [mwifiex] [ 36.960000] [ERET ]: mwifiex_scan_networks+0x18a/0x198c [mwifiex] [ 36.980000] [STAT32]: 0x00000206 : K E2 E1 [ 36.980000] BTA: 0x700736e2 SP: 0x866a7d0c FP: 0x5faddc84 [ 37.000000] LPS: 0x806a37ec LPE: 0x806a37fa LPC: 0x00000000 [ 37.000000] r00: 0x8677f401 r01: 0x8668aa08 r02: 0x00000001 r03: 0x00000000 r04: 0x8668b600 r05: 0x8677f406 r06: 0x8702b600 r07: 0x00000000 r08: 0x8702b600 r09: 0x00000000 r10: 0x870b3b00 r11: 0x00000000 r12: 0x00000000 [ 37.040000] [ 37.040000] Stack Trace: [ 37.040000] mwifiex_scan_networks+0x18a/0x198c [mwifiex] Root cause: mwifiex driver calls is_zero_ether_addr() against byte-aligned address: drivers/net/wireless/marvell/mwifiex/fw.h: struct mwifiex_scan_cmd_config { /* * BSS mode to be sent in the firmware command */ u8 bss_mode; /* Specific BSSID used to filter scan results in the firmware */ u8 specific_bssid[ETH_ALEN]; ... } __packed; drivers/net/wireless/marvell/mwifiex/scan.c: mwifiex_config_scan(..., struct mwifiex_scan_cmd_config *scan_cfg_out, ...) ... if (adapter->ext_scan && !is_zero_ether_addr(scan_cfg_out->specific_bssid)) { ... } Since firmware-related struct mwifiex_scan_cmd_config cannot be changed, modify is_zero_ether_addr() to handle byte-aligned addresses. Cc: Kalle Valo Cc: David S. Miller Cc: Joe Perches Cc: Amitkumar Karwar Signed-off-by: Petri Gynther --- include/linux/etherdevice.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h index 37ff4a6..0cfd243 100644 --- a/include/linux/etherdevice.h +++ b/include/linux/etherdevice.h @@ -90,11 +90,13 @@ static inline bool is_link_local_ether_addr(const u8 *addr) * @addr: Pointer to a six-byte array containing the Ethernet address * * Return true if the address is all zeroes. - * - * Please note: addr must be aligned to u16. */ static inline bool is_zero_ether_addr(const u8 *addr) { + if ((u32)addr & 0x1) + return (addr[0] | addr[1] | addr[2] | addr[3] | addr[4] | + addr[5]) == 0; + #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) return ((*(const u32 *)addr) | (*(const u16 *)(addr + 4))) == 0; #else -- 2.8.0.rc3.226.g39d4020