From c1e5c2f0cb8a22ec2e14af92afc7006491bebabb Mon Sep 17 00:00:00 2001 From: Pablo Sun Date: Thu, 4 Aug 2022 11:48:03 +0800 Subject: usb: typec: altmodes/displayport: correct pin assignment for UFP receptacles Fix incorrect pin assignment values when connecting to a monitor with Type-C receptacle instead of a plug. According to specification, an UFP_D receptacle's pin assignment should came from the UFP_D pin assignments field (bit 23:16), while an UFP_D plug's assignments are described in the DFP_D pin assignments (bit 15:8) during Mode Discovery. For example the LG 27 UL850-W is a monitor with Type-C receptacle. The monitor responds to MODE DISCOVERY command with following DisplayPort Capability flag: dp->alt->vdo=0x140045 The existing logic only take cares of UPF_D plug case, and would take the bit 15:8 for this 0x140045 case. This results in an non-existing pin assignment 0x0 in dp_altmode_configure. To fix this problem a new set of macros are introduced to take plug/receptacle differences into consideration. Fixes: 0e3bb7d6894d ("usb: typec: Add driver for DisplayPort alternate mode") Cc: stable@vger.kernel.org Co-developed-by: Pablo Sun Co-developed-by: Macpaul Lin Reviewed-by: Guillaume Ranquet Reviewed-by: Heikki Krogerus Signed-off-by: Pablo Sun Signed-off-by: Macpaul Lin Link: https://lore.kernel.org/r/20220804034803.19486-1-macpaul.lin@mediatek.com Signed-off-by: Greg Kroah-Hartman --- include/linux/usb/typec_dp.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include') diff --git a/include/linux/usb/typec_dp.h b/include/linux/usb/typec_dp.h index cfb916cccd31..8d09c2f0a9b8 100644 --- a/include/linux/usb/typec_dp.h +++ b/include/linux/usb/typec_dp.h @@ -73,6 +73,11 @@ enum { #define DP_CAP_USB BIT(7) #define DP_CAP_DFP_D_PIN_ASSIGN(_cap_) (((_cap_) & GENMASK(15, 8)) >> 8) #define DP_CAP_UFP_D_PIN_ASSIGN(_cap_) (((_cap_) & GENMASK(23, 16)) >> 16) +/* Get pin assignment taking plug & receptacle into consideration */ +#define DP_CAP_PIN_ASSIGN_UFP_D(_cap_) ((_cap_ & DP_CAP_RECEPTACLE) ? \ + DP_CAP_UFP_D_PIN_ASSIGN(_cap_) : DP_CAP_DFP_D_PIN_ASSIGN(_cap_)) +#define DP_CAP_PIN_ASSIGN_DFP_D(_cap_) ((_cap_ & DP_CAP_RECEPTACLE) ? \ + DP_CAP_DFP_D_PIN_ASSIGN(_cap_) : DP_CAP_UFP_D_PIN_ASSIGN(_cap_)) /* DisplayPort Status Update VDO bits */ #define DP_STATUS_CONNECTION(_status_) ((_status_) & 3) -- cgit v1.2.3-59-g8ed1b From 9c6d778800b921bde3bff3cff5003d1650f942d1 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Fri, 26 Aug 2022 15:31:32 -0400 Subject: USB: core: Prevent nested device-reset calls Automatic kernel fuzzing revealed a recursive locking violation in usb-storage: ============================================ WARNING: possible recursive locking detected 5.18.0 #3 Not tainted -------------------------------------------- kworker/1:3/1205 is trying to acquire lock: ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at: usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 but task is already holding lock: ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at: usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 ... stack backtrace: CPU: 1 PID: 1205 Comm: kworker/1:3 Not tainted 5.18.0 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2988 [inline] check_deadlock kernel/locking/lockdep.c:3031 [inline] validate_chain kernel/locking/lockdep.c:3816 [inline] __lock_acquire.cold+0x152/0x3ca kernel/locking/lockdep.c:5053 lock_acquire kernel/locking/lockdep.c:5665 [inline] lock_acquire+0x1ab/0x520 kernel/locking/lockdep.c:5630 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x14f/0x1610 kernel/locking/mutex.c:747 usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230 usb_reset_device+0x37d/0x9a0 drivers/usb/core/hub.c:6109 r871xu_dev_remove+0x21a/0x270 drivers/staging/rtl8712/usb_intf.c:622 usb_unbind_interface+0x1bd/0x890 drivers/usb/core/driver.c:458 device_remove drivers/base/dd.c:545 [inline] device_remove+0x11f/0x170 drivers/base/dd.c:537 __device_release_driver drivers/base/dd.c:1222 [inline] device_release_driver_internal+0x1a7/0x2f0 drivers/base/dd.c:1248 usb_driver_release_interface+0x102/0x180 drivers/usb/core/driver.c:627 usb_forced_unbind_intf+0x4d/0xa0 drivers/usb/core/driver.c:1118 usb_reset_device+0x39b/0x9a0 drivers/usb/core/hub.c:6114 This turned out not to be an error in usb-storage but rather a nested device reset attempt. That is, as the rtl8712 driver was being unbound from a composite device in preparation for an unrelated USB reset (that driver does not have pre_reset or post_reset callbacks), its ->remove routine called usb_reset_device() -- thus nesting one reset call within another. Performing a reset as part of disconnect processing is a questionable practice at best. However, the bug report points out that the USB core does not have any protection against nested resets. Adding a reset_in_progress flag and testing it will prevent such errors in the future. Link: https://lore.kernel.org/all/CAB7eexKUpvX-JNiLzhXBDWgfg2T9e9_0Tw4HQ6keN==voRbP0g@mail.gmail.com/ Cc: stable@vger.kernel.org Reported-and-tested-by: Rondreis Signed-off-by: Alan Stern Link: https://lore.kernel.org/r/YwkflDxvg0KWqyZK@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hub.c | 10 ++++++++++ include/linux/usb.h | 2 ++ 2 files changed, 12 insertions(+) (limited to 'include') diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 2633acde7ac1..d4b1e70d1498 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -6038,6 +6038,11 @@ re_enumerate: * the reset is over (using their post_reset method). * * Return: The same as for usb_reset_and_verify_device(). + * However, if a reset is already in progress (for instance, if a + * driver doesn't have pre_ or post_reset() callbacks, and while + * being unbound or re-bound during the ongoing reset its disconnect() + * or probe() routine tries to perform a second, nested reset), the + * routine returns -EINPROGRESS. * * Note: * The caller must own the device lock. For example, it's safe to use @@ -6071,6 +6076,10 @@ int usb_reset_device(struct usb_device *udev) return -EISDIR; } + if (udev->reset_in_progress) + return -EINPROGRESS; + udev->reset_in_progress = 1; + port_dev = hub->ports[udev->portnum - 1]; /* @@ -6135,6 +6144,7 @@ int usb_reset_device(struct usb_device *udev) usb_autosuspend_device(udev); memalloc_noio_restore(noio_flag); + udev->reset_in_progress = 0; return ret; } EXPORT_SYMBOL_GPL(usb_reset_device); diff --git a/include/linux/usb.h b/include/linux/usb.h index f7a9914fc97f..9ff1ad4dfad1 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -575,6 +575,7 @@ struct usb3_lpm_parameters { * @devaddr: device address, XHCI: assigned by HW, others: same as devnum * @can_submit: URBs may be submitted * @persist_enabled: USB_PERSIST enabled for this device + * @reset_in_progress: the device is being reset * @have_langid: whether string_langid is valid * @authorized: policy has said we can use it; * (user space) policy determines if we authorize this device to be @@ -662,6 +663,7 @@ struct usb_device { unsigned can_submit:1; unsigned persist_enabled:1; + unsigned reset_in_progress:1; unsigned have_langid:1; unsigned authorized:1; unsigned authenticated:1; -- cgit v1.2.3-59-g8ed1b