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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id x25sm2353911pge.23.2020.06.03.16.32.12 (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 02/10] drbd: Remove uninitialized_var() usage Date: Wed, 3 Jun 2020 16:31:55 -0700 Message-Id: <20200603233203.1695403-3-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 X-Rspamd-Queue-Id: 6D3093D663 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam05 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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. [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 Reviewed-by: Nick Desaulniers --- drivers/block/drbd/drbd_state.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/block/drbd/drbd_state.c b/drivers/block/drbd/drbd_state.c index eeaa3b49b264..0067d328f0b5 100644 --- a/drivers/block/drbd/drbd_state.c +++ b/drivers/block/drbd/drbd_state.c @@ -1604,7 +1604,7 @@ static void broadcast_state_change(struct drbd_state_change *state_change) unsigned int n_device, n_connection, n_peer_device, n_peer_devices; void (*last_func)(struct sk_buff *, unsigned int, void *, enum drbd_notification_type) = NULL; - void *uninitialized_var(last_arg); + void *last_arg = NULL; #define HAS_CHANGED(state) ((state)[OLD] != (state)[NEW]) #define FINAL_STATE_CHANGE(type) \