kernel/linux.git/drivers/usb/core/driver.c, branch v4.14.85

USB: remove LPM management from usb_driver_claim_interface()

2018-10-04T00:00:56+00:00

commit c183813fcee44a249339b7c46e1ad271ca1870aa upstream. usb_driver_claim_interface() disables and re-enables Link Power Management, but it shouldn't do either one, for the reasons listed below. This patch removes the two LPM-related function calls from the routine. The reason for disabling LPM in the analogous function usb_probe_interface() is so that drivers won't have to deal with unwanted LPM transitions in their probe routine. But usb_driver_claim_interface() doesn't call the driver's probe routine (or any other callbacks), so that reason doesn't apply here. Furthermore, no driver other than usbfs will ever call usb_driver_claim_interface() unless it is already bound to another interface in the same device, which means disabling LPM here would be redundant. usbfs doesn't interact with LPM at all. Lastly, the error return from usb_unlocked_disable_lpm() isn't handled properly; the code doesn't clean up its earlier actions before returning. Signed-off-by: Alan Stern Fixes: 8306095fd2c1 ("USB: Disable USB 3.0 LPM in critical sections.") CC: Signed-off-by: Greg Kroah-Hartman

USB: fix error handling in usb_driver_claim_interface()

2018-10-04T00:00:55+00:00

commit bd729f9d67aa9a303d8925bb8c4f06af25f407d1 upstream. The syzbot fuzzing project found a use-after-free bug in the USB core. The bug was caused by usbfs not unbinding from an interface when the USB device file was closed, which led another process to attempt the unbind later on, after the private data structure had been deallocated. The reason usbfs did not unbind the interface at the appropriate time was because it thought the interface had never been claimed in the first place. This was caused by the fact that usb_driver_claim_interface() does not clean up properly when device_bind_driver() returns an error. Although the error code gets passed back to the caller, the iface->dev.driver pointer remains set and iface->condition remains equal to USB_INTERFACE_BOUND. This patch adds proper error handling to usb_driver_claim_interface(). Signed-off-by: Alan Stern Reported-by: syzbot+f84aa7209ccec829536f@syzkaller.appspotmail.com CC: Signed-off-by: Greg Kroah-Hartman

usb: hub: Do not attempt to autosuspend disconnected devices

2017-03-23T07:13:22+00:00

While running a bind/unbind stress test with the dwc3 usb driver on rk3399, the following crash was observed. Unable to handle kernel NULL pointer dereference at virtual address 00000218 pgd = ffffffc00165f000 [00000218] *pgd=000000000174f003, *pud=000000000174f003, *pmd=0000000001750003, *pte=00e8000001751713 Internal error: Oops: 96000005 [#1] PREEMPT SMP Modules linked in: uinput uvcvideo videobuf2_vmalloc cmac ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat rfcomm xt_mark fuse bridge stp llc zram btusb btrtl btbcm btintel bluetooth ip6table_filter mwifiex_pcie mwifiex cfg80211 cdc_ether usbnet r8152 mii joydev snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device ppp_async ppp_generic slhc tun CPU: 1 PID: 29814 Comm: kworker/1:1 Not tainted 4.4.52 #507 Hardware name: Google Kevin (DT) Workqueue: pm pm_runtime_work task: ffffffc0ac540000 ti: ffffffc0af4d4000 task.ti: ffffffc0af4d4000 PC is at autosuspend_check+0x74/0x174 LR is at autosuspend_check+0x70/0x174 ... Call trace: [] autosuspend_check+0x74/0x174 [] usb_runtime_idle+0x20/0x40 [] __rpm_callback+0x48/0x7c [] rpm_idle+0x1e8/0x498 [] pm_runtime_work+0x88/0xcc [] process_one_work+0x390/0x6b8 [] worker_thread+0x480/0x610 [] kthread+0x164/0x178 [] ret_from_fork+0x10/0x40 Source: (gdb) l *0xffffffc00080dcc0 0xffffffc00080dcc0 is in autosuspend_check (drivers/usb/core/driver.c:1778). 1773 /* We don't need to check interfaces that are 1774 * disabled for runtime PM. Either they are unbound 1775 * or else their drivers don't support autosuspend 1776 * and so they are permanently active. 1777 */ 1778 if (intf->dev.power.disable_depth) 1779 continue; 1780 if (atomic_read(&intf->dev.power.usage_count) > 0) 1781 return -EBUSY; 1782 w |= intf->needs_remote_wakeup; Code analysis shows that intf is set to NULL in usb_disable_device() prior to setting actconfig to NULL. At the same time, usb_runtime_idle() does not lock the usb device, and neither does any of the functions in the traceback. This means that there is no protection against a race condition where usb_disable_device() is removing dev->actconfig->interface[] pointers while those are being accessed from autosuspend_check(). To solve the problem, synchronize and validate device state between autosuspend_check() and usb_disconnect(). Acked-by: Alan Stern Signed-off-by: Guenter Roeck Cc: stable Signed-off-by: Greg Kroah-Hartman

usb: hub: Fix error loop seen after hub communication errors

2017-03-23T07:13:22+00:00

While stress testing a usb controller using a bind/unbind looop, the following error loop was observed. usb 7-1.2: new low-speed USB device number 3 using xhci-hcd usb 7-1.2: hub failed to enable device, error -108 usb 7-1-port2: cannot disable (err = -22) usb 7-1-port2: couldn't allocate usb_device usb 7-1-port2: cannot disable (err = -22) hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: activate --> -22 hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: activate --> -22 hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: activate --> -22 hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: activate --> -22 hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: activate --> -22 hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: activate --> -22 hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: activate --> -22 hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: activate --> -22 hub 7-1:1.0: hub_ext_port_status failed (err = -22) hub 7-1:1.0: hub_ext_port_status failed (err = -22) ** 57 printk messages dropped ** hub 7-1:1.0: activate --> -22 ** 82 printk messages dropped ** hub 7-1:1.0: hub_ext_port_status failed (err = -22) This continues forever. After adding tracebacks into the code, the call sequence leading to this is found to be as follows. [] hub_activate+0x368/0x7b8 [] hub_resume+0x2c/0x3c [] usb_resume_interface.isra.6+0x128/0x158 [] usb_suspend_both+0x1e8/0x288 [] usb_runtime_suspend+0x3c/0x98 [] __rpm_callback+0x48/0x7c [] rpm_callback+0xa8/0xd4 [] rpm_suspend+0x84/0x758 [] rpm_idle+0x2c8/0x498 [] __pm_runtime_idle+0x60/0xac [] usb_autopm_put_interface+0x6c/0x7c [] hub_event+0x10ac/0x12ac [] process_one_work+0x390/0x6b8 [] worker_thread+0x480/0x610 [] kthread+0x164/0x178 [] ret_from_fork+0x10/0x40 kick_hub_wq() is called from hub_activate() even after failures to communicate with the hub. This results in an endless sequence of hub event -> hub activate -> wq trigger -> hub event -> ... Provide two solutions for the problem. - Only trigger the hub event queue if communication with the hub is successful. - After a suspend failure, only resume already suspended interfaces if the communication with the device is still possible. Each of the changes fixes the observed problem. Use both to improve robustness. Acked-by: Alan Stern Signed-off-by: Guenter Roeck Cc: stable Signed-off-by: Greg Kroah-Hartman

USB: core: add missing license information to some files

2016-10-29T16:51:56+00:00

Some of the USB core files were missing explicit license information. As all files in the kernel tree are implicitly licensed under the GPLv2-only, be explicit in case someone get confused looking at individual files by using the SPDX nomenclature. Signed-off-by: Greg Kroah-Hartman

USB: leave LPM alone if possible when binding/unbinding interface drivers

2016-05-03T21:32:07+00:00

When a USB driver is bound to an interface (either through probing or by claiming it) or is unbound from an interface, the USB core always disables Link Power Management during the transition and then re-enables it afterward. The reason is because the driver might want to prevent hub-initiated link power transitions, in which case the HCD would have to recalculate the various LPM parameters. This recalculation takes place when LPM is re-enabled and the new parameters are sent to the device and its parent hub. However, if the driver does not want to prevent hub-initiated link power transitions then none of this work is necessary. The parameters don't need to be recalculated, and LPM doesn't need to be disabled and re-enabled. It turns out that disabling and enabling LPM can be time-consuming, enough so that it interferes with user programs that want to claim and release interfaces rapidly via usbfs. Since the usbfs kernel driver doesn't set the disable_hub_initiated_lpm flag, we can speed things up and get the user programs to work by leaving LPM alone whenever the flag isn't set. And while we're improving the way disable_hub_initiated_lpm gets used, let's also fix its kerneldoc. Signed-off-by: Alan Stern Tested-by: Matthew Giassa CC: Mathias Nyman CC: Signed-off-by: Greg Kroah-Hartman

USB: usb_driver_claim_interface: add sanity checking

2016-03-18T16:19:02+00:00

Attacks that trick drivers into passing a NULL pointer to usb_driver_claim_interface() using forged descriptors are known. This thwarts them by sanity checking. Signed-off-by: Oliver Neukum CC: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

usb: core: driver: Use kmalloc_array

2015-10-04T09:47:19+00:00

Use kmalloc_array instead of kmalloc to allocate memory for an array. Also, remove the dev_warn for a memory leak, making the if check more sleek. Signed-off-by: Muhammad Falak R Wani Signed-off-by: Greg Kroah-Hartman

usb: interface authorization: Control interface probing and claiming

2015-09-22T19:08:40+00:00

Driver probings and interface claims get rejected if an interface is not authorized. Signed-off-by: Stefan Koch Signed-off-by: Greg Kroah-Hartman

Revert "usb: interface authorization: Control interface probing and claiming"

2015-08-18T16:58:26+00:00

This reverts commit de7718bd9c4d3db96991a98c2a0cb38258a04e47 as the signed-off-by address is invalid. Cc: Stefan Koch Signed-off-by: Greg Kroah-Hartman