In pxa3xx_gcu_write, a count parameter of type size_t is passed to words of type int. Then, copy_from_user may cause a heap overflow because it is used as the third argument of copy_from_user. Signed-off-by: Hyunwoo Kim <imv4bel@xxxxxxxxx> --- drivers/video/fbdev/pxa3xx-gcu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/video/fbdev/pxa3xx-gcu.c b/drivers/video/fbdev/pxa3xx-gcu.c index 043cc8f9ef1c..5ca6d37e365f 100644 --- a/drivers/video/fbdev/pxa3xx-gcu.c +++ b/drivers/video/fbdev/pxa3xx-gcu.c @@ -389,7 +389,7 @@ pxa3xx_gcu_write(struct file *file, const char *buff, priv->shared->num_words += words; /* Last word reserved for batch buffer end command */ - if (words >= PXA3XX_GCU_BATCH_WORDS) + if (words >= PXA3XX_GCU_BATCH_WORDS || words < 0) return -E2BIG; /* Wait for a free buffer */ -- 2.25.1
