From fbfd76746adc16d64be29ff113f673b70bc3f5c2 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Thu, 25 Jun 2026 22:17:54 -0700 Subject: [PATCH] Input: synaptics-rmi4 - block s_input when F54 queue is busy Changing the input (diagnostic report type) mid-stream changes the report size. Since V4L2 buffers are allocated based on the size at stream start, changing the input while streaming could lead to a heap buffer overflow if the new size is larger than the allocated buffers. Prevent this by blocking VIDIOC_S_INPUT with -EBUSY if the V4L2 queue is busy (streaming). Fixes: 3a762dbd5347 ("[media] Input: synaptics-rmi4 - add support for F54 diagnostics") Cc: stable@vger.kernel.org Assisted-by: Antigravity:gemini-3.5-flash Reviewed-by: Hans Verkuil Link: https://patch.msgid.link/20260626051802.4033172-5-dmitry.torokhov@gmail.com Signed-off-by: Dmitry Torokhov --- drivers/input/rmi4/rmi_f54.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/input/rmi4/rmi_f54.c b/drivers/input/rmi4/rmi_f54.c index 75839a54656b..345646612032 100644 --- a/drivers/input/rmi4/rmi_f54.c +++ b/drivers/input/rmi4/rmi_f54.c @@ -445,7 +445,12 @@ static int rmi_f54_set_input(struct f54_data *f54, unsigned int i) static int rmi_f54_vidioc_s_input(struct file *file, void *priv, unsigned int i) { - return rmi_f54_set_input(video_drvdata(file), i); + struct f54_data *f54 = video_drvdata(file); + + if (vb2_is_busy(&f54->queue)) + return -EBUSY; + + return rmi_f54_set_input(f54, i); } static int rmi_f54_vidioc_g_input(struct file *file, void *priv, -- 2.47.3