From fed4626501c871890da287bec62a96e52da1af89 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Fri, 27 Mar 2026 11:45:20 +0100 Subject: [PATCH 1/2] can: ucan: fix devres lifetime USB drivers bind to USB interfaces and any device managed resources should have their lifetime tied to the interface rather than parent USB device. This avoids issues like memory leaks when drivers are unbound without their devices being physically disconnected (e.g. on probe deferral or configuration changes). Fix the control message buffer lifetime so that it is released on driver unbind. Fixes: 9f2d3eae88d2 ("can: ucan: add driver for Theobroma Systems UCAN devices") Cc: stable@vger.kernel.org # 4.19 Cc: Jakob Unterwurzacher Signed-off-by: Johan Hovold Link: https://patch.msgid.link/20260327104520.1310158-1-johan@kernel.org Signed-off-by: Marc Kleine-Budde --- drivers/net/can/usb/ucan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/can/usb/ucan.c b/drivers/net/can/usb/ucan.c index 0ea0ac75e42f..ee3c1abbd063 100644 --- a/drivers/net/can/usb/ucan.c +++ b/drivers/net/can/usb/ucan.c @@ -1397,7 +1397,7 @@ static int ucan_probe(struct usb_interface *intf, */ /* Prepare Memory for control transfers */ - ctl_msg_buffer = devm_kzalloc(&udev->dev, + ctl_msg_buffer = devm_kzalloc(&intf->dev, sizeof(union ucan_ctl_payload), GFP_KERNEL); if (!ctl_msg_buffer) { From a535a9217ca3f2fccedaafb2fddb4c48f27d36dc Mon Sep 17 00:00:00 2001 From: Samuel Page Date: Wed, 8 Apr 2026 15:30:13 +0100 Subject: [PATCH 2/2] can: raw: fix ro->uniq use-after-free in raw_rcv() raw_release() unregisters raw CAN receive filters via can_rx_unregister(), but receiver deletion is deferred with call_rcu(). This leaves a window where raw_rcv() may still be running in an RCU read-side critical section after raw_release() frees ro->uniq, leading to a use-after-free of the percpu uniq storage. Move free_percpu(ro->uniq) out of raw_release() and into a raw-specific socket destructor. can_rx_unregister() takes an extra reference to the socket and only drops it from the RCU callback, so freeing uniq from sk_destruct ensures the percpu area is not released until the relevant callbacks have drained. Fixes: 514ac99c64b2 ("can: fix multiple delivery of a single CAN frame for overlapping CAN filters") Cc: stable@vger.kernel.org # v4.1+ Assisted-by: Bynario AI Signed-off-by: Samuel Page Link: https://patch.msgid.link/26ec626d-cae7-4418-9782-7198864d070c@bynar.io Acked-by: Oliver Hartkopp [mkl: applied manually] Signed-off-by: Marc Kleine-Budde --- net/can/raw.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/net/can/raw.c b/net/can/raw.c index eee244ffc31e..58a96e933deb 100644 --- a/net/can/raw.c +++ b/net/can/raw.c @@ -361,6 +361,14 @@ static int raw_notifier(struct notifier_block *nb, unsigned long msg, return NOTIFY_DONE; } +static void raw_sock_destruct(struct sock *sk) +{ + struct raw_sock *ro = raw_sk(sk); + + free_percpu(ro->uniq); + can_sock_destruct(sk); +} + static int raw_init(struct sock *sk) { struct raw_sock *ro = raw_sk(sk); @@ -387,6 +395,8 @@ static int raw_init(struct sock *sk) if (unlikely(!ro->uniq)) return -ENOMEM; + sk->sk_destruct = raw_sock_destruct; + /* set notifier */ spin_lock(&raw_notifier_lock); list_add_tail(&ro->notifier, &raw_notifier_list); @@ -436,7 +446,6 @@ static int raw_release(struct socket *sock) ro->bound = 0; ro->dev = NULL; ro->count = 0; - free_percpu(ro->uniq); sock_orphan(sk); sock->sk = NULL;