From: Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx> commit 7105e92c60c9cc4112c782d69c172e96b69a43dc upstream. This patch intended to fix an well-knonw issue in old drivers where the endpoint type is taken for granted, which is often triggered by fuzzers. That was the case for this driver [1], and although the fix seems to be correct, it uncovered another issue that leads to a regression [2], if the endpoints of the current interface are checked. The driver makes use of endpoints that belong to a different interface rather than the one it binds (it binds to the third interface, but also accesses an endpoint from a different one). The driver should claim the interfaces it requires, but that is still not the case. Given that the regression is more severe than the issue found by syzkaller, the best approach is reverting the patch that causes the regression, and trying to fix the underlying problem before checking the endpoint types again. Note that reverting this patch will probably trigger the syzkaller bug at some point. This reverts commit 2b9c3eb32a699acdd4784d6b93743271b4970899. Link: https://syzkaller.appspot.com/bug?extid=348331f63b034f89b622 [1] Link: https://lore.kernel.org/linux-input/87sf161jjc.wl-tiwai@xxxxxxx/ [2] Fixes: 2b9c3eb32a69 ("Input: bcm5974 - check endpoint type before starting traffic") Reported-by: Jacopo Radice <jacopo.radice@xxxxxxxxxxx> Closes: https://bugzilla.suse.com/show_bug.cgi?id=1220030 Signed-off-by: Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx> Link: https://lore.kernel.org/r/20240305-revert_bcm5974_ep_check-v3-1-527198cf6499@xxxxxxxxx Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/input/mouse/bcm5974.c | 20 -------------------- 1 file changed, 20 deletions(-) --- a/drivers/input/mouse/bcm5974.c +++ b/drivers/input/mouse/bcm5974.c @@ -19,7 +19,6 @@ * Copyright (C) 2006 Nicolas Boichat (nicolas@xxxxxxxxxx) */ -#include "linux/usb.h" #include <linux/kernel.h> #include <linux/errno.h> #include <linux/slab.h> @@ -194,8 +193,6 @@ enum tp_type { /* list of device capability bits */ #define HAS_INTEGRATED_BUTTON 1 -/* maximum number of supported endpoints (currently trackpad and button) */ -#define MAX_ENDPOINTS 2 /* trackpad finger data block size */ #define FSIZE_TYPE1 (14 * sizeof(__le16)) @@ -894,18 +891,6 @@ static int bcm5974_resume(struct usb_int return error; } -static bool bcm5974_check_endpoints(struct usb_interface *iface, - const struct bcm5974_config *cfg) -{ - u8 ep_addr[MAX_ENDPOINTS + 1] = {0}; - - ep_addr[0] = cfg->tp_ep; - if (cfg->tp_type == TYPE1) - ep_addr[1] = cfg->bt_ep; - - return usb_check_int_endpoints(iface, ep_addr); -} - static int bcm5974_probe(struct usb_interface *iface, const struct usb_device_id *id) { @@ -918,11 +903,6 @@ static int bcm5974_probe(struct usb_inte /* find the product index */ cfg = bcm5974_get_config(udev); - if (!bcm5974_check_endpoints(iface, cfg)) { - dev_err(&iface->dev, "Unexpected non-int endpoint\n"); - return -ENODEV; - } - /* allocate memory for our device state and initialize it */ dev = kzalloc(sizeof(struct bcm5974), GFP_KERNEL); input_dev = input_allocate_device(); Patches currently in stable-queue which might be from javier.carrasco.cruz@xxxxxxxxx are queue-6.6/revert-input-bcm5974-check-endpoint-type-before-starting-traffic.patch queue-6.6/input-bcm5974-check-endpoint-type-before-starting-tr.patch
