From: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> commit c3dadc19b7564c732598b30d637c6f275c3b77b6 upstream. Attempting to transmit rx_done messages after the GLINK instance is being torn down will cause use after free and memory leaks. So cancel the intent_work and free up the pending intents. With this there are no concurrent accessors of the channel left during qcom_glink_native_remove() and there is therefor no need to hold the spinlock during this operation - which would prohibit the use of cancel_work_sync() in the release function. So remove this. Fixes: 1d2ea36eead9 ("rpmsg: glink: Add rx done command") Cc: stable@xxxxxxxxxxxxxxx Acked-by: Chris Lew <clew@xxxxxxxxxxxxxx> Tested-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx> Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/rpmsg/qcom_glink_native.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) --- a/drivers/rpmsg/qcom_glink_native.c +++ b/drivers/rpmsg/qcom_glink_native.c @@ -243,11 +243,23 @@ static void qcom_glink_channel_release(s { struct glink_channel *channel = container_of(ref, struct glink_channel, refcount); + struct glink_core_rx_intent *intent; struct glink_core_rx_intent *tmp; unsigned long flags; int iid; + /* cancel pending rx_done work */ + cancel_work_sync(&channel->intent_work); + spin_lock_irqsave(&channel->intent_lock, flags); + /* Free all non-reuse intents pending rx_done work */ + list_for_each_entry_safe(intent, tmp, &channel->done_intents, node) { + if (!intent->reuse) { + kfree(intent->data); + kfree(intent); + } + } + idr_for_each_entry(&channel->liids, tmp, iid) { kfree(tmp->data); kfree(tmp); @@ -1597,7 +1609,6 @@ void qcom_glink_native_remove(struct qco struct glink_channel *channel; int cid; int ret; - unsigned long flags; disable_irq(glink->irq); cancel_work_sync(&glink->rx_work); @@ -1606,7 +1617,6 @@ void qcom_glink_native_remove(struct qco if (ret) dev_warn(glink->dev, "Can't remove GLINK devices: %d\n", ret); - spin_lock_irqsave(&glink->idr_lock, flags); /* Release any defunct local channels, waiting for close-ack */ idr_for_each_entry(&glink->lcids, channel, cid) kref_put(&channel->refcount, qcom_glink_channel_release); @@ -1617,7 +1627,6 @@ void qcom_glink_native_remove(struct qco idr_destroy(&glink->lcids); idr_destroy(&glink->rcids); - spin_unlock_irqrestore(&glink->idr_lock, flags); mbox_free_channel(glink->mbox_chan); } EXPORT_SYMBOL_GPL(qcom_glink_native_remove);