Marc Kleine-Budde c1f3f9797c can: netlink: can_changelink(): fix NULL pointer deref of struct can_priv::do_set_mode ... Andrei Lalaev reported a NULL pointer deref when a CAN device is restarted from Bus Off and the driver does not implement the struct can_priv::do_set_mode callback. There are 2 code path that call struct can_priv::do_set_mode: - directly by a manual restart from the user space, via can_changelink() - delayed automatic restart after bus off (deactivated by default) To prevent the NULL pointer deference, refuse a manual restart or configure the automatic restart delay in can_changelink() and report the error via extack to user space. As an additional safety measure let can_restart() return an error if can_priv::do_set_mode is not set instead of dereferencing it unchecked. Reported-by: Andrei Lalaev <andrey.lalaev@gmail.com> Closes: https://lore.kernel.org/all/20250714175520.307467-1-andrey.lalaev@gmail.com Fixes: 39549eef35 ("can: CAN Network device driver and Netlink interface") Link: https://patch.msgid.link/20250718-fix-nullptr-deref-do_set_mode-v1-1-0b520097bb96@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>		2025-07-22 12:55:13 +02:00
..
bittiming.c	can: bittiming: can_validate_bitrate(): report error via netlink	2023-02-06 13:57:27 +01:00
calc_bittiming.c	can: bittiming: can_calc_bittiming(): convert from netdev_err() to NL_SET_ERR_MSG_FMT()	2023-02-06 13:57:27 +01:00
dev.c	can: netlink: can_changelink(): fix NULL pointer deref of struct can_priv::do_set_mode	2025-07-22 12:55:13 +02:00
length.c	can: length: refactor frame lengths definition to add size in bits	2023-06-22 09:43:40 +02:00
Makefile	can: Kconfig: add CONFIG_CAN_RX_OFFLOAD	2022-06-11 17:11:02 +02:00
netlink.c	can: netlink: can_changelink(): fix NULL pointer deref of struct can_priv::do_set_mode	2025-07-22 12:55:13 +02:00
rx-offload.c	netdev: replace napi_reschedule with napi_schedule	2023-10-11 17:28:06 -07:00
skb.c	can: dev: can_put_echo_skb(): don't crash kernel if can_priv::echo_skb is accessed out of bounds	2023-10-05 21:34:13 +02:00