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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id n69sm7060385pjc.25.2020.06.19.20.30.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Jun 2020 20:30:20 -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-doc@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 v2 11/16] media: sur40: Remove uninitialized_var() usage Date: Fri, 19 Jun 2020 20:30:02 -0700 Message-Id: <20200620033007.1444705-12-keescook@chromium.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200620033007.1444705-1-keescook@chromium.org> References: <20200620033007.1444705-1-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 remove this variable since it was actually unused: drivers/input/touchscreen/sur40.c:459:6: warning: variable 'packet_id' set but not used [-Wunused-but-set-variable] 459 | u32 packet_id; | ^~~~~~~~~ However, in keeping with the documentation desires outlined in commit 335abaea7a27 ("Input: sur40 - silence unnecessary noisy debug output"), comment out the assignment instead of removing it. [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/ Fixes: 335abaea7a27 ("Input: sur40 - silence unnecessary noisy debug output") Signed-off-by: Kees Cook --- drivers/input/touchscreen/sur40.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/input/touchscreen/sur40.c b/drivers/input/touchscreen/sur40.c index 34d31c7ec8ba..620cdd7d214a 100644 --- a/drivers/input/touchscreen/sur40.c +++ b/drivers/input/touchscreen/sur40.c @@ -456,8 +456,6 @@ static void sur40_poll(struct input_dev *input) { struct sur40_state *sur40 = input_get_drvdata(input); int result, bulk_read, need_blobs, packet_blobs, i; - u32 uninitialized_var(packet_id); - struct sur40_header *header = &sur40->bulk_in_buffer->header; struct sur40_blob *inblob = &sur40->bulk_in_buffer->blobs[0]; @@ -491,7 +489,7 @@ static void sur40_poll(struct input_dev *input) if (need_blobs == -1) { need_blobs = le16_to_cpu(header->count); dev_dbg(sur40->dev, "need %d blobs\n", need_blobs); - packet_id = le32_to_cpu(header->packet_id); + /* packet_id = le32_to_cpu(header->packet_id); */ } /*