Peter writes:
Fixes one issue with dequeuing requests after disabling endpoint for cdnsp udc driver
* tag 'v5.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/peter.chen/usb:
usb: cdnsp: Fixes issue with dequeuing requests after disabling endpoint
In host mode port connection status flag is "0" when loading
the driver. After loading the driver system asserts suspend
which is handled by "_dwc2_hcd_suspend()" function. Before
the system suspend the port connection status is "0". As
result need to check the "port_connect_status" if it is "0",
then skipping entering to suspend.
Cc: <stable@vger.kernel.org> # 5.2
Fixes: 6f6d70597c ("usb: dwc2: bus suspend/resume for hosts with DWC2_POWER_DOWN_PARAM_NONE")
Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Link: https://lore.kernel.org/r/20210326102510.BDEDEA005D@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This LTE modem (M.2 card) has a bug in its power management:
there is some kind of race condition for U3 wake-up between the host and
the device. The modem firmware sometimes crashes/locks when both events
happen at the same time and the modem fully drops off the USB bus (and
sometimes re-enumerates, sometimes just gets stuck until the next
reboot).
Tested with the modem wired to the XHCI controller on an AMD 3015Ce
platform. Without the patch, the modem dropped of the USB bus 5 times in
3 days. With the quirk, it stayed connected for a week while the
'runtime_suspended_time' counter incremented as excepted.
Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
Link: https://lore.kernel.org/r/20210319124802.2315195-1-vpalatin@chromium.org
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make sure to always claim the data interface and bail out if binding
fails.
Note that the driver had a check to verify that the data interface was
not already bound to a driver but would not detect other failures (e.g.
if the interface was not authorised).
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210322155318.9837-8-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
init_dma_pools() calls dma_pool_create(...dev->dev) to create dma pool.
however, dev->dev is actually set after calling init_dma_pools(), which
effectively makes dma_pool_create(..NULL) and cause crash.
To fix this issue, init dma only after dev->dev is set.
[ 1.317993] RIP: 0010:dma_pool_create+0x83/0x290
[ 1.323257] Call Trace:
[ 1.323390] ? pci_write_config_word+0x27/0x30
[ 1.323626] init_dma_pools+0x41/0x1a0 [snps_udc_core]
[ 1.323899] udc_pci_probe+0x202/0x2b1 [amd5536udc_pci]
Fixes: 7c51247a1f (usb: gadget: udc: Provide correct arguments for 'dma_pool_create')
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Link: https://lore.kernel.org/r/20210317230400.357756-1-ztong0001@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the gadget driver doesn't specify a max_speed, then use the
controller's maximum supported speed as default. For DWC_usb32 IP, the
gadget's speed maybe limited to gen2x1 rate only if the driver's
max_speed is unknown. This scenario should not occur with the current
implementation since the default gadget driver's max_speed should always
be specified. However, to make the driver more robust and help with
readability, let's cover all the scenarios in __dwc3_gadget_set_speed().
Fixes: 450b9e9fab ("usb: dwc3: gadget: Set speed only up to the max supported")
Cc: <stable@vger.kernel.org>
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/55ac7001af73bfe9bc750c6446ef4ac8cf6f9313.1615254129.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The ACPI probe starts failing since commit bea46b9815 ("usb: dwc3:
qcom: Add interconnect support in dwc3 driver"), because there is no
interconnect support for ACPI, and of_icc_get() call in
dwc3_qcom_interconnect_init() will just return -EINVAL.
Fix the problem by skipping interconnect init for ACPI probe, and then
the NULL icc_path_ddr will simply just scheild all ICC calls.
Fixes: bea46b9815 ("usb: dwc3: qcom: Add interconnect support in dwc3 driver")
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210311060318.25418-1-shawn.guo@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull USB and Thunderbolt driver fixes from Greg KH:
"Here are some small Thunderbolt and USB driver fixes for some reported
issues:
- thunderbolt fixes for minor problems
- typec fixes for power issues
- usb-storage quirk addition
- usbip bugfix
- dwc3 bugfix when stopping transfers
- cdnsp bugfix for isoc transfers
- gadget use-after-free fix
All have been in linux-next this week with no reported issues"
* tag 'usb-5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: typec: tcpm: Skip sink_cap query only when VDM sm is busy
usb: dwc3: gadget: Prevent EP queuing while stopping transfers
usb: typec: tcpm: Invoke power_supply_changed for tcpm-source-psy-
usb: typec: Remove vdo[3] part of tps6598x_rx_identity_reg struct
usb-storage: Add quirk to defeat Kindle's automatic unload
usb: gadget: configfs: Fix KASAN use-after-free
usbip: Fix incorrect double assignment to udc->ud.tcp_rx
usb: cdnsp: Fixes incorrect value in ISOC TRB
thunderbolt: Increase runtime PM reference count on DP tunnel discovery
thunderbolt: Initialize HopID IDAs in tb_switch_alloc()
In the situations where the DWC3 gadget stops active transfers, once
calling the dwc3_gadget_giveback(), there is a chance where a function
driver can queue a new USB request in between the time where the dwc3
lock has been released and re-aquired. This occurs after we've already
issued an ENDXFER command. When the stop active transfers continues
to remove USB requests from all dep lists, the newly added request will
also be removed, while controller still has an active TRB for it.
This can lead to the controller accessing an unmapped memory address.
Fix this by ensuring parameters to prevent EP queuing are set before
calling the stop active transfers API.
Fixes: ae7e86108b ("usb: dwc3: Stop active transfers before halting the controller")
Signed-off-by: Wesley Cheng <wcheng@codeaurora.org>
Link: https://lore.kernel.org/r/1615507142-23097-1-git-send-email-wcheng@codeaurora.org
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove the unused "u32 vdo[3]" part in the tps6598x_rx_identity_reg
struct. This helps avoid "failed to register partner" errors which
happen when tps6598x_read_partner_identity() fails because the
amount of data read is 12 bytes smaller than the struct size.
Note that vdo[3] is already in usb_pd_identity and hence
shouldn't be added to tps6598x_rx_identity_reg as well.
Fixes: f6c56ca91b ("usb: typec: Add the Product Type VDOs to struct usb_pd_identity")
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Guido Günther <agx@sigxcpu.org>
Signed-off-by: Elias Rudberg <mail@eliasrudberg.se>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210311124710.6563-1-mail@eliasrudberg.se
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Matthias reports that the Amazon Kindle automatically removes its
emulated media if it doesn't receive another SCSI command within about
one second after a SYNCHRONIZE CACHE. It does so even when the host
has sent a PREVENT MEDIUM REMOVAL command. The reason for this
behavior isn't clear, although it's not hard to make some guesses.
At any rate, the results can be unexpected for anyone who tries to
access the Kindle in an unusual fashion, and in theory they can lead
to data loss (for example, if one file is closed and synchronized
while other files are still in the middle of being written).
To avoid such problems, this patch creates a new usb-storage quirks
flag telling the driver always to issue a REQUEST SENSE following a
SYNCHRONIZE CACHE command, and adds an unusual_devs entry for the
Kindle with the flag set. This is sufficient to prevent the Kindle
from doing its automatic unload, without interfering with proper
operation.
Another possible way to deal with this would be to increase the
frequency of TEST UNIT READY polling that the kernel normally carries
out for removable-media storage devices. However that would increase
the overall load on the system and it is not as reliable, because the
user can override the polling interval. Changing the driver's
behavior is safer and has minimal overhead.
CC: <stable@vger.kernel.org>
Reported-and-tested-by: Matthias Schwarzott <zzam@gentoo.org>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20210317190654.GA497856@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When gadget is disconnected, running sequence is like this.
. composite_disconnect
. Call trace:
usb_string_copy+0xd0/0x128
gadget_config_name_configuration_store+0x4
gadget_config_name_attr_store+0x40/0x50
configfs_write_file+0x198/0x1f4
vfs_write+0x100/0x220
SyS_write+0x58/0xa8
. configfs_composite_unbind
. configfs_composite_bind
In configfs_composite_bind, it has
"cn->strings.s = cn->configuration;"
When usb_string_copy is invoked. it would
allocate memory, copy input string, release previous pointed memory space,
and use new allocated memory.
When gadget is connected, host sends down request to get information.
Call trace:
usb_gadget_get_string+0xec/0x168
lookup_string+0x64/0x98
composite_setup+0xa34/0x1ee8
If gadget is disconnected and connected quickly, in the failed case,
cn->configuration memory has been released by usb_string_copy kfree but
configfs_composite_bind hasn't been run in time to assign new allocated
"cn->configuration" pointer to "cn->strings.s".
When "strlen(s->s) of usb_gadget_get_string is being executed, the dangling
memory is accessed, "BUG: KASAN: use-after-free" error occurs.
Cc: stable@vger.kernel.org
Signed-off-by: Jim Lin <jilin@nvidia.com>
Signed-off-by: Macpaul Lin <macpaul.lin@mediatek.com>
Link: https://lore.kernel.org/r/1615444961-13376-1-git-send-email-macpaul.lin@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
MODULE_SUPPORTED_DEVICE was added in pre-git era and never was
implemented. We can safely remove it, because the kernel has grown
to have many more reliable mechanisms to determine if device is
supported or not.
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Peter writes:
It fixed one incorrect value issue for cdns ssp driver
* tag 'usb-v5.12-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/peter.chen/usb:
usb: cdnsp: Fixes incorrect value in ISOC TRB
Pull USB fixes from Greg KH:
"Here are a small number of USB fixes for 5.12-rc3 to resolve a bunch
of reported issues:
- usbip fixups for issues found by syzbot
- xhci driver fixes and quirk additions
- gadget driver fixes
- dwc3 QCOM driver fix
- usb-serial new ids and fixes
- usblp fix for a long-time issue
- cdc-acm quirk addition
- other tiny fixes for reported problems
All of these have been in linux-next for a while with no reported
issues"
* tag 'usb-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (25 commits)
xhci: Fix repeated xhci wake after suspend due to uncleared internal wake state
usb: xhci: Fix ASMedia ASM1042A and ASM3242 DMA addressing
xhci: Improve detection of device initiated wake signal.
usb: xhci: do not perform Soft Retry for some xHCI hosts
usbip: fix vudc usbip_sockfd_store races leading to gpf
usbip: fix vhci_hcd attach_store() races leading to gpf
usbip: fix stub_dev usbip_sockfd_store() races leading to gpf
usbip: fix vudc to check for stream socket
usbip: fix vhci_hcd to check for stream socket
usbip: fix stub_dev to check for stream socket
usb: dwc3: qcom: Add missing DWC3 OF node refcount decrement
USB: usblp: fix a hang in poll() if disconnected
USB: gadget: udc: s3c2410_udc: fix return value check in s3c2410_udc_probe()
usb: renesas_usbhs: Clear PIPECFG for re-enabling pipe with other EPNUM
usb: dwc3: qcom: Honor wakeup enabled/disabled state
usb: gadget: f_uac1: stop playback on function disable
usb: gadget: f_uac2: always increase endpoint max_packet_size by one audio slot
USB: gadget: u_ether: Fix a configfs return code
usb: dwc3: qcom: add ACPI device id for sc8180x
Goodix Fingerprint device is not a modem
...
Fixes issue with priority of operator. Operator "|" priority is
higher then "? :".
To improve the readability the operator "? :" has been replaced with
"if ()" statement.
Fixes: 3d82904559 ("usb: cdnsp: cdns3 Add main part of Cadence USBSSP DRD Driver")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Signed-off-by: Peter Chen <peter.chen@kernel.org>
If port terminations are detected in suspend, but link never reaches U0
then xHCI may have an internal uncleared wake state that will cause an
immediate wake after suspend.
This wake state is normally cleared when driver clears the PORT_CSC bit,
which is set after a device is enabled and in U0.
Write 1 to clear PORT_CSC for ports that don't have anything connected
when suspending. This makes sure any pending internal wake states in
xHCI are cleared.
Cc: stable@vger.kernel.org
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210311115353.2137560-5-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A xHC USB 3 port might miss the first wake signal from a USB 3 device
if the port LFPS reveiver isn't enabled fast enough after xHC resume.
xHC host will anyway be resumed by a PME# signal, but will go back to
suspend if no port activity is seen.
The device resends the U3 LFPS wake signal after a 100ms delay, but
by then host is already suspended, starting all over from the
beginning of this issue.
USB 3 specs say U3 wake LFPS signal is sent for max 10ms, then device
needs to delay 100ms before resending the wake.
Don't suspend immediately if port activity isn't detected in resume.
Instead add a retry. If there is no port activity then delay for 120ms,
and re-check for port activity.
Cc: <stable@vger.kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210311115353.2137560-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB devices cannot perform DMA and hence have no dma_mask set in their
device structure. Therefore importing dmabuf into a USB-based driver
fails, which breaks joining and mirroring of display in X11.
For USB devices, pick the associated USB controller as attachment device.
This allows the DRM import helpers to perform the DMA setup. If the DMA
controller does not support DMA transfers, we're out of luck and cannot
import. Our current USB-based DRM drivers don't use DMA, so the actual
DMA device is not important.
Tested by joining/mirroring displays of udl and radeon under Gnome/X11.
v8:
* release dmadev if device initialization fails (Noralf)
* fix commit description (Noralf)
v7:
* fix use-before-init bug in gm12u320 (Dan)
v6:
* implement workaround in DRM drivers and hold reference to
DMA device while USB device is in use
* remove dev_is_usb() (Greg)
* collapse USB helper into usb_intf_get_dma_device() (Alan)
* integrate Daniel's TODO statement (Daniel)
* fix typos (Greg)
v5:
* provide a helper for USB interfaces (Alan)
* add FIXME item to documentation and TODO list (Daniel)
v4:
* implement workaround with USB helper functions (Greg)
* use struct usb_device->bus->sysdev as DMA device (Takashi)
v3:
* drop gem_create_object
* use DMA mask of USB controller, if any (Daniel, Christian, Noralf)
v2:
* move fix to importer side (Christian, Daniel)
* update SHMEM and CMA helpers for new PRIME callbacks
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 6eb0233ec2 ("usb: don't inherity DMA properties for USB devices")
Tested-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org> # v5.10+
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210303133229.3288-1-tzimmermann@suse.de
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Johan writes:
USB-serial fixes for 5.12-rc3
Here's a fix for a long-standing memory leak after probe failure in
io_edgeport and a fix for a NULL-deref on disconnect in the new xr
driver.
Included are also some new device ids.
All have been in linux-next with no reported issues.
* tag 'usb-serial-5.12-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
USB: serial: io_edgeport: fix memory leak in edge_startup
USB: serial: ch341: add new Product ID
USB: serial: xr: fix NULL-deref on disconnect
USB: serial: cp210x: add some more GE USB IDs
USB: serial: cp210x: add ID for Acuity Brands nLight Air Adapter
usbip_sockfd_store() is invoked when user requests attach (import)
detach (unimport) usb gadget device from usbip host. vhci_hcd sends
import request and usbip_sockfd_store() exports the device if it is
free for export.
Export and unexport are governed by local state and shared state
- Shared state (usbip device status, sockfd) - sockfd and Device
status are used to determine if stub should be brought up or shut
down. Device status is shared between host and client.
- Local state (tcp_socket, rx and tx thread task_struct ptrs)
A valid tcp_socket controls rx and tx thread operations while the
device is in exported state.
- While the device is exported, device status is marked used and socket,
sockfd, and thread pointers are valid.
Export sequence (stub-up) includes validating the socket and creating
receive (rx) and transmit (tx) threads to talk to the client to provide
access to the exported device. rx and tx threads depends on local and
shared state to be correct and in sync.
Unexport (stub-down) sequence shuts the socket down and stops the rx and
tx threads. Stub-down sequence relies on local and shared states to be
in sync.
There are races in updating the local and shared status in the current
stub-up sequence resulting in crashes. These stem from starting rx and
tx threads before local and global state is updated correctly to be in
sync.
1. Doesn't handle kthread_create() error and saves invalid ptr in local
state that drives rx and tx threads.
2. Updates tcp_socket and sockfd, starts stub_rx and stub_tx threads
before updating usbip_device status to SDEV_ST_USED. This opens up a
race condition between the threads and usbip_sockfd_store() stub up
and down handling.
Fix the above problems:
- Stop using kthread_get_run() macro to create/start threads.
- Create threads and get task struct reference.
- Add kthread_create() failure handling and bail out.
- Hold usbip_device lock to update local and shared states after
creating rx and tx threads.
- Update usbip_device status to SDEV_ST_USED.
- Update usbip_device tcp_socket, sockfd, tcp_rx, and tcp_tx
- Start threads after usbip_device (tcp_socket, sockfd, tcp_rx, tcp_tx,
and status) is complete.
Credit goes to syzbot and Tetsuo Handa for finding and root-causing the
kthread_get_run() improper error handling problem and others. This is a
hard problem to find and debug since the races aren't seen in a normal
case. Fuzzing forces the race window to be small enough for the
kthread_get_run() error path bug and starting threads before updating the
local and shared state bug in the stub-up sequence.
Fixes: 9720b4bc76 ("staging/usbip: convert to kthread")
Cc: stable@vger.kernel.org
Reported-by: syzbot <syzbot+a93fba6d384346a761e3@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+bf1a360e305ee719e364@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+95ce4b142579611ef0a9@syzkaller.appspotmail.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/b1c08b983ffa185449c9f0f7d1021dc8c8454b60.1615171203.git.skhan@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
attach_store() is invoked when user requests import (attach) a device
from usbip host.
Attach and detach are governed by local state and shared state
- Shared state (usbip device status) - Device status is used to manage
the attach and detach operations on import-able devices.
- Local state (tcp_socket, rx and tx thread task_struct ptrs)
A valid tcp_socket controls rx and tx thread operations while the
device is in exported state.
- Device has to be in the right state to be attached and detached.
Attach sequence includes validating the socket and creating receive (rx)
and transmit (tx) threads to talk to the host to get access to the
imported device. rx and tx threads depends on local and shared state to
be correct and in sync.
Detach sequence shuts the socket down and stops the rx and tx threads.
Detach sequence relies on local and shared states to be in sync.
There are races in updating the local and shared status in the current
attach sequence resulting in crashes. These stem from starting rx and
tx threads before local and global state is updated correctly to be in
sync.
1. Doesn't handle kthread_create() error and saves invalid ptr in local
state that drives rx and tx threads.
2. Updates tcp_socket and sockfd, starts stub_rx and stub_tx threads
before updating usbip_device status to VDEV_ST_NOTASSIGNED. This opens
up a race condition between the threads, port connect, and detach
handling.
Fix the above problems:
- Stop using kthread_get_run() macro to create/start threads.
- Create threads and get task struct reference.
- Add kthread_create() failure handling and bail out.
- Hold vhci and usbip_device locks to update local and shared states after
creating rx and tx threads.
- Update usbip_device status to VDEV_ST_NOTASSIGNED.
- Update usbip_device tcp_socket, sockfd, tcp_rx, and tcp_tx
- Start threads after usbip_device (tcp_socket, sockfd, tcp_rx, tcp_tx,
and status) is complete.
Credit goes to syzbot and Tetsuo Handa for finding and root-causing the
kthread_get_run() improper error handling problem and others. This is
hard problem to find and debug since the races aren't seen in a normal
case. Fuzzing forces the race window to be small enough for the
kthread_get_run() error path bug and starting threads before updating the
local and shared state bug in the attach sequence.
- Update usbip_device tcp_rx and tcp_tx pointers holding vhci and
usbip_device locks.
Tested with syzbot reproducer:
- https://syzkaller.appspot.com/text?tag=ReproC&x=14801034d00000
Fixes: 9720b4bc76 ("staging/usbip: convert to kthread")
Cc: stable@vger.kernel.org
Reported-by: syzbot <syzbot+a93fba6d384346a761e3@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+bf1a360e305ee719e364@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+95ce4b142579611ef0a9@syzkaller.appspotmail.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/bb434bd5d7a64fbec38b5ecfb838a6baef6eb12b.1615171203.git.skhan@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
usbip_sockfd_store() is invoked when user requests attach (import)
detach (unimport) usb device from usbip host. vhci_hcd sends import
request and usbip_sockfd_store() exports the device if it is free
for export.
Export and unexport are governed by local state and shared state
- Shared state (usbip device status, sockfd) - sockfd and Device
status are used to determine if stub should be brought up or shut
down.
- Local state (tcp_socket, rx and tx thread task_struct ptrs)
A valid tcp_socket controls rx and tx thread operations while the
device is in exported state.
- While the device is exported, device status is marked used and socket,
sockfd, and thread pointers are valid.
Export sequence (stub-up) includes validating the socket and creating
receive (rx) and transmit (tx) threads to talk to the client to provide
access to the exported device. rx and tx threads depends on local and
shared state to be correct and in sync.
Unexport (stub-down) sequence shuts the socket down and stops the rx and
tx threads. Stub-down sequence relies on local and shared states to be
in sync.
There are races in updating the local and shared status in the current
stub-up sequence resulting in crashes. These stem from starting rx and
tx threads before local and global state is updated correctly to be in
sync.
1. Doesn't handle kthread_create() error and saves invalid ptr in local
state that drives rx and tx threads.
2. Updates tcp_socket and sockfd, starts stub_rx and stub_tx threads
before updating usbip_device status to SDEV_ST_USED. This opens up a
race condition between the threads and usbip_sockfd_store() stub up
and down handling.
Fix the above problems:
- Stop using kthread_get_run() macro to create/start threads.
- Create threads and get task struct reference.
- Add kthread_create() failure handling and bail out.
- Hold usbip_device lock to update local and shared states after
creating rx and tx threads.
- Update usbip_device status to SDEV_ST_USED.
- Update usbip_device tcp_socket, sockfd, tcp_rx, and tcp_tx
- Start threads after usbip_device (tcp_socket, sockfd, tcp_rx, tcp_tx,
and status) is complete.
Credit goes to syzbot and Tetsuo Handa for finding and root-causing the
kthread_get_run() improper error handling problem and others. This is a
hard problem to find and debug since the races aren't seen in a normal
case. Fuzzing forces the race window to be small enough for the
kthread_get_run() error path bug and starting threads before updating the
local and shared state bug in the stub-up sequence.
Tested with syzbot reproducer:
- https://syzkaller.appspot.com/text?tag=ReproC&x=14801034d00000
Fixes: 9720b4bc76 ("staging/usbip: convert to kthread")
Cc: stable@vger.kernel.org
Reported-by: syzbot <syzbot+a93fba6d384346a761e3@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+bf1a360e305ee719e364@syzkaller.appspotmail.com>
Reported-by: syzbot <syzbot+95ce4b142579611ef0a9@syzkaller.appspotmail.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/268a0668144d5ff36ec7d87fdfa90faf583b7ccc.1615171203.git.skhan@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
