From b662b162c3d06f120749eea0351ec9317d9dd905 Mon Sep 17 00:00:00 2001 From: Feng Jiang Date: Wed, 9 Apr 2025 09:46:33 +0800 Subject: [PATCH] drm: Fix potential overflow issue in event_string array MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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 Reviewed-by: André Almeida Reviewed-by: Raag Jadav Link: https://lore.kernel.org/r/20250409014633.31303-1-jiangfeng@kylinos.cn Signed-off-by: Rodrigo Vivi --- drivers/gpu/drm/drm_drv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) 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) -- 2.50.1