From 2ddd03309433d39852945c2f85d36e796c558793 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Wed, 24 Nov 2021 11:38:57 +0100 Subject: [PATCH] media: cec: safely unhook lists in cec_data smatch warns about data->list not being removed from list: drivers/media/cec/core/cec-adap.c:926 cec_transmit_msg_fh() warn: '&data->list' not removed from list It is a false warning, but it doesn't hurt to make the code more robust and safely unhook data->list and data->xfer_list together with a WARN_ON if this is actually ever needed (this really shouldn't happen). Note that fixing the data->list warning just replaced it with a new similar warning for data->xfer_list, so both needed to be addressed. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/cec/core/cec-adap.c | 8 +++++++- drivers/media/cec/core/cec-api.c | 2 +- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/media/cec/core/cec-adap.c b/drivers/media/cec/core/cec-adap.c index 79fa36d..da73eb5 100644 --- a/drivers/media/cec/core/cec-adap.c +++ b/drivers/media/cec/core/cec-adap.c @@ -342,7 +342,7 @@ static void cec_data_completed(struct cec_data *data) * Without that we would be referring to a closed filehandle. */ if (data->fh) - list_del(&data->xfer_list); + list_del_init(&data->xfer_list); if (data->blocking) { /* @@ -898,6 +898,8 @@ int cec_transmit_msg_fh(struct cec_adapter *adap, struct cec_msg *msg, if (fh) list_add_tail(&data->xfer_list, &fh->xfer_list); + else + INIT_LIST_HEAD(&data->xfer_list); list_add_tail(&data->list, &adap->transmit_queue); adap->transmit_queue_sz++; @@ -923,6 +925,10 @@ int cec_transmit_msg_fh(struct cec_adapter *adap, struct cec_msg *msg, /* The transmit completed (possibly with an error) */ *msg = data->msg; + if (WARN_ON(!list_empty(&data->list))) + list_del(&data->list); + if (WARN_ON(!list_empty(&data->xfer_list))) + list_del(&data->xfer_list); kfree(data); return 0; } diff --git a/drivers/media/cec/core/cec-api.c b/drivers/media/cec/core/cec-api.c index 769e6b4..0edb714 100644 --- a/drivers/media/cec/core/cec-api.c +++ b/drivers/media/cec/core/cec-api.c @@ -669,7 +669,7 @@ static int cec_release(struct inode *inode, struct file *filp) data->blocking = false; data->fh = NULL; - list_del(&data->xfer_list); + list_del_init(&data->xfer_list); } mutex_unlock(&adap->lock); while (!list_empty(&fh->msgs)) { -- 2.7.4