From: Tuo Li islituo@gmail.com
stable inclusion from stable-5.10.67 commit 2254383788ff93a423e20068333b9f8376d56cb4 bugzilla: 182619 https://gitee.com/openeuler/kernel/issues/I4EWO7
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit a211260c34cfadc6068fece8c9e99e0fe1e2a2b6 ]
The variable val is declared without initialization, and its address is passed to amdgpu_i2c_get_byte(). In this function, the value of val is accessed in: DRM_DEBUG("i2c 0x%02x 0x%02x read failed\n", addr, *val);
Also, when amdgpu_i2c_get_byte() returns, val may remain uninitialized, but it is accessed in: val &= ~amdgpu_connector->router.ddc_mux_control_pin;
To fix this possible uninitialized-variable access, initialize val to 0 in amdgpu_i2c_router_select_ddc_port().
Reported-by: TOTE Robot oslab@tsinghua.edu.cn Signed-off-by: Tuo Li islituo@gmail.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Chen Jun chenjun102@huawei.com Acked-by: Weilong Chen chenweilong@huawei.com
Signed-off-by: Chen Jun chenjun102@huawei.com --- drivers/gpu/drm/amd/amdgpu/amdgpu_i2c.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_i2c.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_i2c.c index 47cad23a6b9e..b91d3d29b410 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_i2c.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_i2c.c @@ -339,7 +339,7 @@ static void amdgpu_i2c_put_byte(struct amdgpu_i2c_chan *i2c_bus, void amdgpu_i2c_router_select_ddc_port(const struct amdgpu_connector *amdgpu_connector) { - u8 val; + u8 val = 0;
if (!amdgpu_connector->router.ddc_valid) return;