[PATCH AUTOSEL 4.19 17/57] usbip: fix vhci_hcd controller counting

Sasha Levin
2019-03-30T01:40:31Z

From: Maciej Żenczykowski <maze@google.com>

[ Upstream commit e0a2e73e501c77037c8756137e87b12c7c3c9793 ]

Without this usbip fails on a machine with devices
that lexicographically come after vhci_hcd.

ie.
$ ls -l /sys/devices/platform
...
drwxr-xr-x. 4 root root 0 Sep 19 16:21 serial8250
-rw-r--r--. 1 root root 4096 Sep 19 23:50 uevent
drwxr-xr-x. 6 root root 0 Sep 20 13:15 vhci_hcd.0
drwxr-xr-x. 4 root root 0 Sep 19 16:22 w83627hf.656

Because it detects 'w83627hf.656' as another vhci_hcd controller,
and then fails to be able to talk to it.

Note: this doesn't actually fix usbip's support for multiple
controllers... that's still broken for other reasons
("vhci_hcd.0" is hardcoded in a string macro), but is enough to
actually make it work on the above machine.

See also:
https://bugzilla.redhat.com/show_bug.cgi?id=1631148

Cc: Jonathan Dieter <jdieter@gmail.com>
Cc: Valentina Manea <valentina.manea.m@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: linux-usb@vger.kernel.org
Signed-off-by: Maciej Żenczykowski <zenczykowski@gmail.com>
Acked-by: Shuah Khan (Samsung OSG) <shuah@kernel.org>
Tested-by: Jonathan Dieter <jdieter@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/usb/usbip/libsrc/vhci_driver.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/usb/usbip/libsrc/vhci_driver.c b/tools/usb/usbip/libsrc/vhci_driver.c
index 4204359c9fee..8159fd98680b 100644
--- a/tools/usb/usbip/libsrc/vhci_driver.c
+++ b/tools/usb/usbip/libsrc/vhci_driver.c
@@ -150,7 +150,7 @@ static int get_nports(struct udev_device *hc_device)

static int vhci_hcd_filter(const struct dirent *dirent)
{
- return strcmp(dirent->d_name, "vhci_hcd") >= 0;
+ return !strncmp(dirent->d_name, "vhci_hcd.", 9);
}

static int get_ncontrollers(void)
--
2.19.1