diff mbox series

[v3] drm: Fix potential overflow issue in event_string array

Message ID 20250409014633.31303-1-jiangfeng@kylinos.cn (mailing list archive)
State New, archived
Headers show
Series [v3] drm: Fix potential overflow issue in event_string array | expand

Commit Message

Feng Jiang April 9, 2025, 1:46 a.m. UTC 
From: Feng Jiang <jiangfeng@kylinos.cn>

When calling scnprintf() to append recovery method to event_string,
the second argument should be `sizeof(event_string) - len`, otherwise
there is a potential overflow problem.

Fixes: b7cf9f4ac1b8 ("drm: Introduce device wedged event")
Signed-off-by: Feng Jiang <jiangfeng@kylinos.cn>
---
v3:
- update the subject

v2:
- update commit message
- keep scnprintf() as a single line
---
 drivers/gpu/drm/drm_drv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

André Almeida April 9, 2025, 4:03 a.m. UTC | #1 
Em 08/04/2025 22:46, jiangfeng@kylinos.cn escreveu:
> From: Feng Jiang <jiangfeng@kylinos.cn>
> 
> When calling scnprintf() to append recovery method to event_string,
> the second argument should be `sizeof(event_string) - len`, otherwise
> there is a potential overflow problem.
> 
> Fixes: b7cf9f4ac1b8 ("drm: Introduce device wedged event")
> Signed-off-by: Feng Jiang <jiangfeng@kylinos.cn>

Reviewed-by: André Almeida <andrealmeid@igalia.com>
Raag Jadav April 9, 2025, 6:24 a.m. UTC | #2 
On Wed, Apr 09, 2025 at 09:46:33AM +0800, jiangfeng@kylinos.cn wrote:
> From: Feng Jiang <jiangfeng@kylinos.cn>
> 
> When calling scnprintf() to append recovery method to event_string,
> the second argument should be `sizeof(event_string) - len`, otherwise
> there is a potential overflow problem.
> 
> Fixes: b7cf9f4ac1b8 ("drm: Introduce device wedged event")
> Signed-off-by: Feng Jiang <jiangfeng@kylinos.cn>

Reviewed-by: Raag Jadav <raag.jadav@intel.com>

Thanks for the fix.
diff mbox series

Patch

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 17fc5dc708f4..60e5ac179c15 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -549,7 +549,7 @@  int drm_dev_wedged_event(struct drm_device *dev, unsigned long method)
 		if (drm_WARN_ONCE(dev, !recovery, "invalid recovery method %u\n", opt))
 			break;
 
-		len += scnprintf(event_string + len, sizeof(event_string), "%s,", recovery);
+		len += scnprintf(event_string + len, sizeof(event_string) - len, "%s,", recovery);
 	}
 
 	if (recovery)