From 9d27705e3ce1b48c5ec58bf10d8aba3c36da859e Mon Sep 17 00:00:00 2001 From: Markus Elfring Date: Sun, 16 Apr 2023 17:30:46 +0200 Subject: [PATCH] drm/bridge: it6505: Move a variable assignment behind a null pointer check in receive_timing_debugfs_show() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ 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 Link: https://patchwork.freedesktop.org/patch/msgid/fa69384f-1485-142b-c4ee-3df54ac68a89@web.de Reviewed-by: Robert Foss Signed-off-by: Robert Foss Signed-off-by: Sasha Levin --- 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 99123eec4551..292c4f6da04a 100644 --- a/drivers/gpu/drm/bridge/ite-it6505.c +++ b/drivers/gpu/drm/bridge/ite-it6505.c @@ -3085,7 +3085,7 @@ 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; @@ -3094,6 +3094,7 @@ 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);