kernel/linux.git/drivers/usb/usbip/stub_dev.c, branch v6.6.134

USB: usbip: fix stub_dev hub disconnect

2023-11-20T10:59:26+00:00

[ Upstream commit 97475763484245916735a1aa9a3310a01d46b008 ] If a hub is disconnected that has device(s) that's attached to the usbip layer the disconnect function might fail because it tries to release the port on an already disconnected hub. Fixes: 6080cd0e9239 ("staging: usbip: claim ports used by shared devices") Signed-off-by: Jonas Blixt Acked-by: Shuah Khan Link: https://lore.kernel.org/r/20230615092810.1215490-1-jonas.blixt@actia.se Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

USB: usbip: missing lock in stub down

2022-10-22T11:22:25+00:00

Missing lock in sysfs operation when we want to close the connection in order to check the status and send the down event in a safe way. Signed-off-by: Jose Ignacio Tornos Martinez Reviewed-by: Shuah Khan Link: https://lore.kernel.org/r/20221003091016.641900-1-jtornosm@redhat.com Signed-off-by: Greg Kroah-Hartman

usbip: convert sysfs snprintf to sysfs_emit

2022-10-22T11:21:23+00:00

Follow the advice of the Documentation/filesystems/sysfs.rst and show() should only use sysfs_emit() or sysfs_emit_at() when formatting the value to be returned to user space. Signed-off-by: Xuezhi Zhang Reviewed-by: Shuah Khan Link: https://lore.kernel.org/r/20221014110606.599352-1-zhangxuezhi3@gmail.com Signed-off-by: Greg Kroah-Hartman

usb: usbip: fix a refcount leak in stub_probe()

2022-04-21T17:01:22+00:00

usb_get_dev() is called in stub_device_alloc(). When stub_probe() fails after that, usb_put_dev() needs to be called to release the reference. Fix this by moving usb_put_dev() to sdev_free error path handling. Find this by code review. Fixes: 3ff67445750a ("usbip: fix error handling in stub_probe()") Reviewed-by: Shuah Khan Signed-off-by: Hangyu Hua Link: https://lore.kernel.org/r/20220412020257.9767-1-hbh25y@gmail.com Signed-off-by: Greg Kroah-Hartman

usbip: stub-dev synchronize sysfs code paths

2021-04-05T07:05:42+00:00

Fuzzing uncovered race condition between sysfs code paths in usbip drivers. Device connect/disconnect code paths initiated through sysfs interface are prone to races if disconnect happens during connect and vice versa. Use sysfs_lock to protect sysfs paths in stub-dev. Cc: stable@vger.kernel.org Reported-and-tested-by: syzbot+a93fba6d384346a761e3@syzkaller.appspotmail.com Signed-off-by: Shuah Khan Link: https://lore.kernel.org/r/2b182f3561b4a065bf3bf6dce3b0e9944ba17b3f.1616807117.git.skhan@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

usbip: fix stub_dev usbip_sockfd_store() races leading to gpf

2021-03-10T18:32:34+00:00

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: 9720b4bc76a83807 ("staging/usbip: convert to kthread") Cc: stable@vger.kernel.org Reported-by: syzbot Reported-by: syzbot Reported-by: syzbot Reported-by: Tetsuo Handa Signed-off-by: Shuah Khan Link: https://lore.kernel.org/r/268a0668144d5ff36ec7d87fdfa90faf583b7ccc.1615171203.git.skhan@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

usbip: fix stub_dev to check for stream socket

2021-03-10T18:32:33+00:00

Fix usbip_sockfd_store() to validate the passed in file descriptor is a stream socket. If the file descriptor passed was a SOCK_DGRAM socket, sock_recvmsg() can't detect end of stream. Cc: stable@vger.kernel.org Suggested-by: Tetsuo Handa Signed-off-by: Shuah Khan Link: https://lore.kernel.org/r/e942d2bd03afb8e8552bd2a5d84e18d17670d521.1615171203.git.skhan@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

Revert "usbip: Implement a match function to fix usbip"

2020-09-25T14:50:11+00:00

This commit reverts commit 7a2f2974f265 ("usbip: Implement a match function to fix usbip"). In summary, commit d5643d2249b2 ("USB: Fix device driver race") inadvertently broke usbip functionality, which I resolved in an incorrect manner by introducing a match function to usbip, usbip_match(), that unconditionally returns true. However, the usbip_match function, as is, causes usbip to take over virtual devices used by syzkaller for USB fuzzing, which is a regression reported by Andrey Konovalov. Furthermore, in conjunction with the fix of another bug, handled by another patch titled "usbcore/driver: Fix specific driver selection" in this patch set, the usbip_match function causes unexpected USB subsystem behaviour when the usbip_host driver is loaded. The unexpected behaviour can be qualified as follows: - If commit 41160802ab8e ("USB: Simplify USB ID table match") is included in the kernel, then all USB devices are bound to the usbip_host driver, which appears to the user as if all USB devices were disconnected. - If the same commit (41160802ab8e) is not in the kernel (as is the case with v5.8.10) then all USB devices are re-probed and re-bound to their original device drivers, which appears to the user as a disconnection and re-connection of USB devices. Please note that this commit will make usbip non-operational again, until yet another patch in this patch set is merged, titled "usbcore/driver: Accommodate usbip". Cc: # 5.8: 41160802ab8e: USB: Simplify USB ID table match Cc: # 5.8 Cc: Bastien Nocera Cc: Valentina Manea Cc: Shuah Khan Cc: Greg Kroah-Hartman Cc: Alan Stern Cc: Reported-by: Andrey Konovalov Tested-by: Andrey Konovalov Acked-by: Shuah Khan Signed-off-by: M. Vefa Bicakci Link: https://lore.kernel.org/r/20200922110703.720960-2-m.v.b@runbox.com Signed-off-by: Greg Kroah-Hartman

usbip: Implement a match function to fix usbip

2020-08-18T09:55:23+00:00

Commit 88b7381a939d ("USB: Select better matching USB drivers when available") introduced the use of a "match" function to select a non-generic/better driver for a particular USB device. This unfortunately breaks the operation of usbip in general, as reported in the kernel bugzilla with bug 208267 (linked below). Upon inspecting the aforementioned commit, one can observe that the original code in the usb_device_match function used to return 1 unconditionally, but the aforementioned commit makes the usb_device_match function use identifier tables and "match" virtual functions, if either of them are available. Hence, this commit implements a match function for usbip that unconditionally returns true to ensure that usbip is functional again. This change has been verified to restore usbip functionality, with a v5.7.y kernel on an up-to-date version of Qubes OS 4.0, which uses usbip to redirect USB devices between VMs. Thanks to Jonathan Dieter for the effort in bisecting this issue down to the aforementioned commit. Fixes: 88b7381a939d ("USB: Select better matching USB drivers when available") Link: https://bugzilla.kernel.org/show_bug.cgi?id=208267 Link: https://bugzilla.redhat.com/show_bug.cgi?id=1856443 Link: https://github.com/QubesOS/qubes-issues/issues/5905 Signed-off-by: M. Vefa Bicakci Cc: # 5.7 Cc: Valentina Manea Cc: Alan Stern Reviewed-by: Bastien Nocera Reviewed-by: Shuah Khan Link: https://lore.kernel.org/r/20200810160017.46002-1-m.v.b@runbox.com Signed-off-by: Greg Kroah-Hartman

USB: usbip: convert to use dev_groups

2019-08-09T05:55:45+00:00

USB drivers now support the ability for the driver core to handle the creation and removal of device-specific sysfs files in a race-free manner. Take advantage of that by converting the driver to use this by moving the sysfs attributes into a group and assigning the dev_groups pointer to it. Cc: Valentina Manea Cc: Shuah Khan Link: https://lore.kernel.org/r/20190806144502.17792-13-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman