On Sat, Feb 26, 2022 at 12:43 AM <broonie@xxxxxxxxxx> wrote:
>
> Hi all,
>
> After merging the drm tree, today's linux-next build (x86 allmodconfig)
> failed like this:
>
> lib/strncpy_from_user.o: warning: objtool: strncpy_from_user()+0x10b: call to do_strncpy_from_user() with UACCESS enabled
> lib/strnlen_user.o: warning: objtool: strnlen_user()+0xbb: call to do_strnlen_user() with UACCESS enabled
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c: In function 'receive_timing_debugfs_show':
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3077:23: error: array subscript 4096 is outside array bounds of 'u8[200]' {aka 'unsigned char[200]'} [-Werror=array-bounds]
> 3077 | u8 *str = read_buf, *end = read_buf + PAGE_SIZE;
> | ^~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3076:5: note: while referencing 'read_buf'
> 3076 | u8 read_buf[READ_BUFFER_SIZE];
> | ^~~~~~~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3077:23: error: array subscript 4096 is outside array bounds of 'u8[200]' {aka 'unsigned char[200]'} [-Werror=array-bounds]
> 3077 | u8 *str = read_buf, *end = read_buf + PAGE_SIZE;
> | ^~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3076:5: note: while referencing 'read_buf'
> 3076 | u8 read_buf[READ_BUFFER_SIZE];
> | ^~~~~~~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3077:23: error: array subscript 4096 is outside array bounds of 'u8[200]' {aka 'unsigned char[200]'} [-Werror=array-bounds]
> 3077 | u8 *str = read_buf, *end = read_buf + PAGE_SIZE;
> | ^~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3076:5: note: while referencing 'read_buf'
> 3076 | u8 read_buf[READ_BUFFER_SIZE];
> | ^~~~~~~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3077:23: error: array subscript 4096 is outside array bounds of 'u8[200]' {aka 'unsigned char[200]'} [-Werror=array-bounds]
> 3077 | u8 *str = read_buf, *end = read_buf + PAGE_SIZE;
> | ^~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3076:5: note: while referencing 'read_buf'
> 3076 | u8 read_buf[READ_BUFFER_SIZE];
> | ^~~~~~~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3077:23: error: array subscript 4096 is outside array bounds of 'u8[200]' {aka 'unsigned char[200]'} [-Werror=array-bounds]
> 3077 | u8 *str = read_buf, *end = read_buf + PAGE_SIZE;
> | ^~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3076:5: note: while referencing 'read_buf'
> 3076 | u8 read_buf[READ_BUFFER_SIZE];
> | ^~~~~~~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3077:23: error: array subscript 4096 is outside array bounds of 'u8[200]' {aka 'unsigned char[200]'} [-Werror=array-bounds]
> 3077 | u8 *str = read_buf, *end = read_buf + PAGE_SIZE;
> | ^~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3076:5: note: while referencing 'read_buf'
> 3076 | u8 read_buf[READ_BUFFER_SIZE];
> | ^~~~~~~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3077:23: error: array subscript 4096 is outside array bounds of 'u8[200]' {aka 'unsigned char[200]'} [-Werror=array-bounds]
> 3077 | u8 *str = read_buf, *end = read_buf + PAGE_SIZE;
> | ^~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3076:5: note: while referencing 'read_buf'
> 3076 | u8 read_buf[READ_BUFFER_SIZE];
> | ^~~~~~~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3077:23: error: array subscript 4096 is outside array bounds of 'u8[200]' {aka 'unsigned char[200]'} [-Werror=array-bounds]
> 3077 | u8 *str = read_buf, *end = read_buf + PAGE_SIZE;
> | ^~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3076:5: note: while referencing 'read_buf'
> 3076 | u8 read_buf[READ_BUFFER_SIZE];
> | ^~~~~~~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3077:23: error: array subscript 4096 is outside array bounds of 'u8[200]' {aka 'unsigned char[200]'} [-Werror=array-bounds]
> 3077 | u8 *str = read_buf, *end = read_buf + PAGE_SIZE;
> | ^~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3076:5: note: while referencing 'read_buf'
> 3076 | u8 read_buf[READ_BUFFER_SIZE];
> | ^~~~~~~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3077:23: error: array subscript 4096 is outside array bounds of 'u8[200]' {aka 'unsigned char[200]'} [-Werror=array-bounds]
> 3077 | u8 *str = read_buf, *end = read_buf + PAGE_SIZE;
> | ^~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3076:5: note: while referencing 'read_buf'
> 3076 | u8 read_buf[READ_BUFFER_SIZE];
> | ^~~~~~~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3077:23: error: array subscript 4096 is outside array bounds of 'u8[200]' {aka 'unsigned char[200]'} [-Werror=array-bounds]
> 3077 | u8 *str = read_buf, *end = read_buf + PAGE_SIZE;
> | ^~~
> /tmp/next/build/drivers/gpu/drm/bridge/ite-it6505.c:3076:5: note: while referencing 'read_buf'
> 3076 | u8 read_buf[READ_BUFFER_SIZE];
> | ^~~~~~~~
> cc1: all warnings being treated as errors
>
> Caused by commit
>
> b5c84a9edcd418 ("drm/bridge: add it6505 driver")
>
> I have used the drm tree from yesterday instead.
hi all,
The following fix should be able to address the errors. Should it be
squashed into b5c84a9edcd418 ("drm/bridge: add it6505 driver")?
diff --git a/drivers/gpu/drm/bridge/ite-it6505.c
b/drivers/gpu/drm/bridge/ite-it6505.c
index fb16a176822d81..f2f101220ade94 100644
--- a/drivers/gpu/drm/bridge/ite-it6505.c
+++ b/drivers/gpu/drm/bridge/ite-it6505.c
@@ -289,7 +289,7 @@
#define WORD_LENGTH_20BIT 2
#define WORD_LENGTH_24BIT 3
#define DEBUGFS_DIR_NAME "it6505-debugfs"
-#define READ_BUFFER_SIZE 200
+#define READ_BUFFER_SIZE 400
/* Vendor option */
#define HDCP_DESIRED 1
@@ -3074,7 +3074,7 @@ static ssize_t
receive_timing_debugfs_show(struct file *file, char __user *buf,
struct it6505 *it6505 = file->private_data;
struct drm_display_mode *vid = &it6505->video_info;
u8 read_buf[READ_BUFFER_SIZE];
- u8 *str = read_buf, *end = read_buf + PAGE_SIZE;
+ u8 *str = read_buf, *end = read_buf + READ_BUFFER_SIZE;
ssize_t ret, count;
if (!it6505)
