From: Vincent Mailhol <mailhol.vincent@wanadoo.fr> stable inclusion from stable-v6.6.79 commit 1590667a60753ee5a54871f2840ceefd4a7831fa category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBPC8Y CVE: CVE-2025-21773 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit a1ad2109ce41c9e3912dadd07ad8a9c640064ffb upstream. The driver assumed that es58x_dev->udev->serial could never be NULL. While this is true on commercially available devices, an attacker could spoof the device identity providing a NULL USB serial number. That would trigger a NULL pointer dereference. Add a check on es58x_dev->udev->serial before accessing it. Reported-by: yan kang <kangyan91@outlook.com> Reported-by: yue sun <samsun1006219@gmail.com> Closes: https://lore.kernel.org/linux-can/SY8P300MB0421E0013C0EBD2AA46BA709A1F42@SY8... Fixes: 9f06631c3f1f ("can: etas_es58x: export product information through devlink_ops::info_get()") Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://patch.msgid.link/20250204154859.9797-2-mailhol.vincent@wanadoo.fr Cc: stable@vger.kernel.org Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Yi Yang <yiyang13@huawei.com> --- drivers/net/can/usb/etas_es58x/es58x_devlink.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/usb/etas_es58x/es58x_devlink.c b/drivers/net/can/usb/etas_es58x/es58x_devlink.c index 635edeb8f68c..e763a9904bed 100644 --- a/drivers/net/can/usb/etas_es58x/es58x_devlink.c +++ b/drivers/net/can/usb/etas_es58x/es58x_devlink.c @@ -248,7 +248,11 @@ static int es58x_devlink_info_get(struct devlink *devlink, return ret; } - return devlink_info_serial_number_put(req, es58x_dev->udev->serial); + if (es58x_dev->udev->serial) + ret = devlink_info_serial_number_put(req, + es58x_dev->udev->serial); + + return ret; } const struct devlink_ops es58x_dl_ops = { -- 2.25.1