From: Markus Elfring elfring@users.sourceforge.net
[ Upstream commit 0be05a75de2916421e88e0d64b001984f54df0bd ]
The address of a data structure member was determined before a corresponding null pointer check in the implementation of the function “receive_timing_debugfs_show”.
Thus avoid the risk for undefined behaviour by moving the assignment for the variable “vid” behind the null pointer check.
This issue was detected by using the Coccinelle software.
Fixes: b5c84a9edcd4 ("drm/bridge: add it6505 driver") Signed-off-by: Markus Elfring elfring@users.sourceforge.net Link: https://patchwork.freedesktop.org/patch/msgid/fa69384f-1485-142b-c4ee-3df54a... Reviewed-by: Robert Foss rfoss@kernel.org Signed-off-by: Robert Foss rfoss@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/bridge/ite-it6505.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c index bc451b2a77c28..32ea61b79965e 100644 --- a/drivers/gpu/drm/bridge/ite-it6505.c +++ b/drivers/gpu/drm/bridge/ite-it6505.c @@ -3195,7 +3195,7 @@ static ssize_t receive_timing_debugfs_show(struct file *file, char __user *buf, size_t len, loff_t *ppos) { struct it6505 *it6505 = file->private_data; - struct drm_display_mode *vid = &it6505->video_info; + struct drm_display_mode *vid; u8 read_buf[READ_BUFFER_SIZE]; u8 *str = read_buf, *end = read_buf + READ_BUFFER_SIZE; ssize_t ret, count; @@ -3204,6 +3204,7 @@ static ssize_t receive_timing_debugfs_show(struct file *file, char __user *buf, return -ENODEV;
it6505_calc_video_info(it6505); + vid = &it6505->video_info; str += scnprintf(str, end - str, "---video timing---\n"); str += scnprintf(str, end - str, "PCLK:%d.%03dMHz\n", vid->clock / 1000, vid->clock % 1000);