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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id j8sm3442213pjw.11.2020.06.03.16.32.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 03 Jun 2020 16:32:12 -0700 (PDT) From: Kees Cook To: linux-kernel@vger.kernel.org Cc: Kees Cook , Linus Torvalds , Miguel Ojeda , Alexander Potapenko , Joe Perches , Andy Whitcroft , x86@kernel.org, drbd-dev@lists.linbit.com, linux-block@vger.kernel.org, b43-dev@lists.infradead.org, netdev@vger.kernel.org, linux-wireless@vger.kernel.org, linux-ide@vger.kernel.org, linux-clk@vger.kernel.org, linux-spi@vger.kernel.org, linux-mm@kvack.org, clang-built-linux@googlegroups.com Subject: [PATCH 03/10] b43: Remove uninitialized_var() usage Date: Wed, 3 Jun 2020 16:31:56 -0700 Message-Id: <20200603233203.1695403-4-keescook@chromium.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200603233203.1695403-1-keescook@chromium.org> References: <20200603233203.1695403-1-keescook@chromium.org> MIME-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. As a precursor to removing[2] this[3] macro[4], just initialize this variable to NULL, and make the (unreachable!) code do a conditional test. [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Signed-off-by: Kees Cook --- drivers/net/wireless/broadcom/b43/phy_n.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/broadcom/b43/phy_n.c b/drivers/net/wireless/broadcom/b43/phy_n.c index d3c001fa8eb4..88cdcea10d61 100644 --- a/drivers/net/wireless/broadcom/b43/phy_n.c +++ b/drivers/net/wireless/broadcom/b43/phy_n.c @@ -4222,7 +4222,7 @@ static void b43_nphy_tx_gain_table_upload(struct b43_wldev *dev) u32 rfpwr_offset; u8 pga_gain, pad_gain; int i; - const s16 *uninitialized_var(rf_pwr_offset_table); + const s16 *rf_pwr_offset_table = NULL; table = b43_nphy_get_tx_gain_table(dev); if (!table) @@ -4256,9 +4256,13 @@ static void b43_nphy_tx_gain_table_upload(struct b43_wldev *dev) pga_gain = (table[i] >> 24) & 0xf; pad_gain = (table[i] >> 19) & 0x1f; if (b43_current_band(dev->wl) == NL80211_BAND_2GHZ) - rfpwr_offset = rf_pwr_offset_table[pad_gain]; + rfpwr_offset = rf_pwr_offset_table + ? rf_pwr_offset_table[pad_gain] + : 0; else - rfpwr_offset = rf_pwr_offset_table[pga_gain]; + rfpwr_offset = rf_pwr_offset_table + ? rf_pwr_offset_table[pga_gain] + : 0; } else { pga_gain = (table[i] >> 24) & 0xF; if (b43_current_band(dev->wl) == NL80211_BAND_2GHZ)