Return-path: Received: from mout.kundenserver.de ([212.227.126.131]:60502 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754099AbcA0NqS (ORCPT ); Wed, 27 Jan 2016 08:46:18 -0500 From: Arnd Bergmann To: Jouni Malinen , Kalle Valo Cc: linux-arm-kernel@lists.infradead.org, Arnd Bergmann , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] hostap: avoid uninitialized variable use in hfa384x_get_rid Date: Wed, 27 Jan 2016 14:45:26 +0100 Message-Id: <1453902342-3420391-1-git-send-email-arnd@arndb.de> (sfid-20160127_144639_297089_3DA92CE1) Sender: linux-wireless-owner@vger.kernel.org List-ID: The driver reads a value from hfa384x_from_bap(), which may fail, and then assigns the value to a local variable. gcc detects that in in the failure case, the 'rlen' variable now contains uninitialized data: In file included from ../drivers/net/wireless/intersil/hostap/hostap_pci.c:220:0: drivers/net/wireless/intersil/hostap/hostap_hw.c: In function 'hfa384x_get_rid': drivers/net/wireless/intersil/hostap/hostap_hw.c:842:5: warning: 'rec' may be used uninitialized in this function [-Wmaybe-uninitialized] if (le16_to_cpu(rec.len) == 0) { To ensure we get consistent error handling here, this changes the code to only set rlen if we actually read data correctly, which also takes care of the warning. Signed-off-by: Arnd Bergmann --- drivers/net/wireless/intersil/hostap/hostap_hw.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/intersil/hostap/hostap_hw.c b/drivers/net/wireless/intersil/hostap/hostap_hw.c index 6df3ee561d52..6dbf8ee9490a 100644 --- a/drivers/net/wireless/intersil/hostap/hostap_hw.c +++ b/drivers/net/wireless/intersil/hostap/hostap_hw.c @@ -839,12 +839,15 @@ static int hfa384x_get_rid(struct net_device *dev, u16 rid, void *buf, int len, if (!res) res = hfa384x_from_bap(dev, BAP0, &rec, sizeof(rec)); - if (le16_to_cpu(rec.len) == 0) { - /* RID not available */ - res = -ENODATA; + if (!res) { + if (le16_to_cpu(rec.len) == 0) { + /* RID not available */ + res = -ENODATA; + } + + rlen = (le16_to_cpu(rec.len) - 1) * 2; } - rlen = (le16_to_cpu(rec.len) - 1) * 2; if (!res && exact_len && rlen != len) { printk(KERN_DEBUG "%s: hfa384x_get_rid - RID len mismatch: " "rid=0x%04x, len=%d (expected %d)\n", -- 2.7.0