[PATCH v3 0/3] media: Fix gcc warnings

[PATCH v3 0/3] media: Fix gcc warnings

[Ricardo Ribalda]

drivers/staging/media/tegra-video/tegra20.c: In function ‘tegra20_vip_start_streaming’:
    drivers/staging/media/tegra-video/tegra20.c:624:72: warning: ‘yuv_input_format’ may be used uninitialized [-Wmaybe-uninitialized]
      624 |                          VI_INPUT_VIP_INPUT_ENABLE | main_input_format | yuv_input_format);
    drivers/staging/media/tegra-video/tegra20.c:617:22: note: ‘yuv_input_format’ was declared here
      617 |         unsigned int yuv_input_format;
          |                      ^~~~~~~~~~~~~~~~
    drivers/media/radio/radio-shark2.c: In function ‘usb_shark_probe’:
    drivers/media/radio/radio-shark2.c:191:17: warning: ‘%s’ directive output may be truncated writing up to 35 bytes into a region of size 32 [-Wformat-truncation=]
      191 |                 .name           = "%s:blue:",
          |                 ^
    In function ‘shark_register_leds’,
        inlined from ‘usb_shark_probe’ at drivers/media/radio/radio-shark2.c:306:11:
    drivers/media/radio/radio-shark2.c:212:17: note: ‘snprintf’ output between 7 and 42 bytes into a destination of size 32
      212 |                 snprintf(shark->led_names[i], sizeof(shark->led_names[0]),
          |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      213 |                          shark->leds[i].name, shark->v4l2_dev.name);
          |                          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    drivers/media/radio/radio-shark2.c: In function ‘usb_shark_probe’:
    drivers/media/radio/radio-shark2.c:197:17: warning: ‘%s’ directive output may be truncated writing up to 35 bytes into a region of size 32 [-Wformat-truncation=]
      197 |                 .name           = "%s:red:",
          |                 ^
    In function ‘shark_register_leds’,
        inlined from ‘usb_shark_probe’ at drivers/media/radio/radio-shark2.c:306:11:
    drivers/media/radio/radio-shark2.c:212:17: note: ‘snprintf’ output between 6 and 41 bytes into a destination of size 32
      212 |                 snprintf(shark->led_names[i], sizeof(shark->led_names[0]),
          |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      213 |                          shark->leds[i].name, shark->v4l2_dev.name);
          |                          ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      AR      drivers/staging/media/tegra-video/built-in.a
      AR      drivers/staging/media/built-in.a
    In file included from ./include/asm-generic/preempt.h:5,
                     from ./arch/arm/include/generated/asm/preempt.h:1,
                     from ./include/linux/preempt.h:79,
                     from ./include/linux/spinlock.h:56,
                     from ./include/linux/mmzone.h:8,
                     from ./include/linux/gfp.h:7,
                     from ./include/linux/umh.h:4,
                     from ./include/linux/kmod.h:9,
                     from ./include/linux/module.h:17,
                     from drivers/media/dvb-core/dvbdev.c:15:
    In function ‘check_object_size’,
        inlined from ‘check_copy_size’ at ./include/linux/thread_info.h:251:2,
        inlined from ‘copy_from_user’ at ./include/linux/uaccess.h:182:6,
        inlined from ‘dvb_usercopy’ at drivers/media/dvb-core/dvbdev.c:987:7:
    ./include/linux/thread_info.h:215:17: warning: ‘sbuf’ may be used uninitialized [-Wmaybe-uninitialized]
      215 |                 __check_object_size(ptr, n, to_user);
          |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ./include/linux/thread_info.h: In function ‘dvb_usercopy’:
    ./include/linux/thread_info.h:208:13: note: by argument 1 of type ‘const void *’ to ‘__check_object_size’ declared here
      208 | extern void __check_object_size(const void *ptr, unsigned long n,
          |             ^~~~~~~~~~~~~~~~~~~
    drivers/media/dvb-core/dvbdev.c:959:17: note: ‘sbuf’ declared here
      959 |         char    sbuf[128];
          |                 ^~~~
      AR      drivers/media/radio/built-in.a

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
Changes in v3: Thanks Luca
- Fix error while rebasing the change from Thierry. (sorry :S)
- Link to v2: https://lore.kernel.org/r/20240325-gcc-arm-warnings-v2-0-47523cf5c8ca@chromium.org

Changes in v2: Thanks Thierry
- Make tegra20_vi_get_output_formats() and tegra20_vi_get_inut_formats,
  consistent.
- Link to v1: https://lore.kernel.org/r/20240323-gcc-arm-warnings-v1-0-0b45cc52f39e@chromium.org

---
Ricardo Ribalda (3):
      staging: media: tegra-video: Fix -Wmaybe-unitialized warn in gcc
      media: radio-shark2: Avoid led_names truncations
      media: dvbdev: Initialize sbuf

 drivers/media/dvb-core/dvbdev.c             | 2 +-
 drivers/media/radio/radio-shark2.c          | 2 +-
 drivers/staging/media/tegra-video/tegra20.c | 1 +
 3 files changed, 3 insertions(+), 2 deletions(-)
---
base-commit: b14257abe7057def6127f6fb2f14f9adc8acabdb
change-id: 20240323-gcc-arm-warnings-e4c142cb5ac0

Best regards,
-- 
Ricardo Ribalda <ribalda@chromium.org>

[PATCH v3 1/3] staging: media: tegra-video: Fix -Wmaybe-unitialized warn in gcc

[Ricardo Ribalda]

Make sure that tegra20_vi_get_input_formats always assign a value for
yuv_input_format.

Fix:
drivers/staging/media/tegra-video/tegra20.c:624:72: warning: ‘yuv_input_format’ may be used uninitialized [-Wmaybe-uninitialized]

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
 drivers/staging/media/tegra-video/tegra20.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/staging/media/tegra-video/tegra20.c b/drivers/staging/media/tegra-video/tegra20.c
index c25286772603c..630e2ff987a37 100644
--- a/drivers/staging/media/tegra-video/tegra20.c
+++ b/drivers/staging/media/tegra-video/tegra20.c
@@ -164,6 +164,7 @@ static void tegra20_vi_get_input_formats(struct tegra_vi_channel *chan,
 	unsigned int input_mbus_code = chan->fmtinfo->code;
 
 	(*main_input_format) = VI_INPUT_INPUT_FORMAT_YUV422;
+	(*yuv_input_format) = VI_INPUT_YUV_INPUT_FORMAT_UYVY;
 
 	switch (input_mbus_code) {
 	case MEDIA_BUS_FMT_UYVY8_2X8:

-- 
2.44.0.396.g6e790dbe36-goog

Re: [PATCH v3 1/3] staging: media: tegra-video: Fix -Wmaybe-unitialized warn in gcc

[Luca Ceresoli]

On Mon, 25 Mar 2024 14:50:23 +0000
Ricardo Ribalda <ribalda@chromium.org> wrote:

> Make sure that tegra20_vi_get_input_formats always assign a value for
> yuv_input_format.
> 
> Fix:
> drivers/staging/media/tegra-video/tegra20.c:624:72: warning: ‘yuv_input_format’ may be used uninitialized [-Wmaybe-uninitialized]
> 
> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>

Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>

-- 
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

[PATCH v3 2/3] media: radio-shark2: Avoid led_names truncations

[Ricardo Ribalda]

Increase the size of led_names so it can fit any valid v4l2 device name.

Fixes:
drivers/media/radio/radio-shark2.c:197:17: warning: ‘%s’ directive output may be truncated writing up to 35 bytes into a region of size 32 [-Wformat-truncation=]

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
 drivers/media/radio/radio-shark2.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/radio/radio-shark2.c b/drivers/media/radio/radio-shark2.c
index f1c5c0a6a335c..e3e6aa87fe081 100644
--- a/drivers/media/radio/radio-shark2.c
+++ b/drivers/media/radio/radio-shark2.c
@@ -62,7 +62,7 @@ struct shark_device {
 #ifdef SHARK_USE_LEDS
 	struct work_struct led_work;
 	struct led_classdev leds[NO_LEDS];
-	char led_names[NO_LEDS][32];
+	char led_names[NO_LEDS][64];
 	atomic_t brightness[NO_LEDS];
 	unsigned long brightness_new;
 #endif

-- 
2.44.0.396.g6e790dbe36-goog

[PATCH v3 3/3] media: dvbdev: Initialize sbuf

[Ricardo Ribalda]

Because the size passed to copy_from_user() cannot be known beforehand,
it needs to be checked during runtime with check_object_size. That makes
gcc believe that the content of sbuf can be used before init.

Fix:
./include/linux/thread_info.h:215:17: warning: ‘sbuf’ may be used uninitialized [-Wmaybe-uninitialized]

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
 drivers/media/dvb-core/dvbdev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/dvb-core/dvbdev.c b/drivers/media/dvb-core/dvbdev.c
index 733d0bc4b4cc3..b43695bc51e75 100644
--- a/drivers/media/dvb-core/dvbdev.c
+++ b/drivers/media/dvb-core/dvbdev.c
@@ -956,7 +956,7 @@ int dvb_usercopy(struct file *file,
 		 int (*func)(struct file *file,
 			     unsigned int cmd, void *arg))
 {
-	char    sbuf[128];
+	char    sbuf[128] = {};
 	void    *mbuf = NULL;
 	void    *parg = NULL;
 	int     err  = -EINVAL;

-- 
2.44.0.396.g6e790dbe36-goog