From: Chris Wulff <crwulff@gmail.com> stable inclusion from stable-v4.19.320 commit ba15815dd24cc5ec0d23e2170dc58c7db1e03b4a category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAOXZ1 CVE: CVE-2024-44960 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 973a57891608a98e894db2887f278777f564de18 upstream. Make sure the descriptor has been set before looking at maxpacket. This fixes a null pointer panic in this case. This may happen if the gadget doesn't properly set up the endpoint for the current speed, or the gadget descriptors are malformed and the descriptor for the speed/endpoint are not found. No current gadget driver is known to have this problem, but this may cause a hard-to-find bug during development of new gadgets. Fixes: 54f83b8c8ea9 ("USB: gadget: Reject endpoints with 0 maxpacket value") Cc: stable@vger.kernel.org Signed-off-by: Chris Wulff <crwulff@gmail.com> Link: https://lore.kernel.org/r/20240725010419.314430-2-crwulff@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ye Bin <yebin10@huawei.com> --- drivers/usb/gadget/udc/core.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c index b45dd7827ff9..1335a715f5dd 100644 --- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -99,12 +99,10 @@ int usb_ep_enable(struct usb_ep *ep) goto out; /* UDC drivers can't handle endpoints with maxpacket size 0 */ - if (usb_endpoint_maxp(ep->desc) == 0) { - /* - * We should log an error message here, but we can't call - * dev_err() because there's no way to find the gadget - * given only ep. - */ + if (!ep->desc || usb_endpoint_maxp(ep->desc) == 0) { + WARN_ONCE(1, "%s: ep%d (%s) has %s\n", __func__, ep->address, ep->name, + (!ep->desc) ? "NULL descriptor" : "maxpacket 0"); + ret = -EINVAL; goto out; } -- 2.34.1