From 89d5dcc48c08b4669a503e99e5f8dc7b5bcd2242 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Wed, 11 Jan 2017 14:40:52 +0100 Subject: [PATCH] clk: stm32f4: avoid uninitialized variable access The failure path in the newly added function tries to free an uninitialized pointer: drivers/clk/clk-stm32f4.c: In function 'stm32f4_rcc_init': drivers/clk/clk-stm32f4.c:1106:4: error: 'gate' may be used uninitialized in this function [-Werror=maybe-uninitialized] I'm adding an initialization to NULL here to make the kfree() succeed, and I'm also rearranging the cleanup so that the same kfree() is used for any error path, making the function slightly more robust against newly introduced bugs in the error handling. Fixes: daf2d117cbca ("clk: stm32f4: Add lcd-tft clock") Signed-off-by: Arnd Bergmann Acked-by: Gabriel Fernandez Signed-off-by: Stephen Boyd --- drivers/clk/clk-stm32f4.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/clk/clk-stm32f4.c b/drivers/clk/clk-stm32f4.c index 42f8534996de..4a3bb6e63525 100644 --- a/drivers/clk/clk-stm32f4.c +++ b/drivers/clk/clk-stm32f4.c @@ -1080,7 +1080,7 @@ static struct clk_hw *stm32_register_aux_clk(const char *name, unsigned long flags, spinlock_t *lock) { struct clk_hw *hw; - struct clk_gate *gate; + struct clk_gate *gate = NULL; struct clk_mux *mux = NULL; struct clk_hw *mux_hw = NULL, *gate_hw = NULL; const struct clk_ops *mux_ops = NULL, *gate_ops = NULL; @@ -1103,7 +1103,6 @@ static struct clk_hw *stm32_register_aux_clk(const char *name, if (offset_mux != NO_MUX) { mux = kzalloc(sizeof(*mux), GFP_KERNEL); if (!mux) { - kfree(gate); hw = ERR_PTR(-EINVAL); goto fail; } @@ -1116,8 +1115,10 @@ static struct clk_hw *stm32_register_aux_clk(const char *name, mux_ops = &clk_mux_ops; } - if (mux_hw == NULL && gate_hw == NULL) - return ERR_PTR(-EINVAL); + if (mux_hw == NULL && gate_hw == NULL) { + hw = ERR_PTR(-EINVAL); + goto fail; + } hw = clk_hw_register_composite(NULL, name, parent_names, num_parents, mux_hw, mux_ops, @@ -1125,11 +1126,12 @@ static struct clk_hw *stm32_register_aux_clk(const char *name, gate_hw, gate_ops, flags); +fail: if (IS_ERR(hw)) { kfree(gate); kfree(mux); } -fail: + return hw; } -- 2.20.1