diff options
| author | Shuah Khan <skhan@linuxfoundation.org> | 2021-03-30 03:36:50 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-04-05 09:05:42 +0200 |
| commit | bd8b82042269a95db48074b8bb400678dbac1815 (patch) | |
| tree | 43af66f344afc0a2222eaad8cf7b1b99642e3f9b | |
| parent | usbip: stub-dev synchronize sysfs code paths (diff) | |
| download | linux-bd8b82042269a95db48074b8bb400678dbac1815.tar.xz linux-bd8b82042269a95db48074b8bb400678dbac1815.zip | |
usbip: vudc synchronize sysfs code paths
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 vudc.
Cc: stable@vger.kernel.org
Reported-and-tested-by: syzbot+a93fba6d384346a761e3@syzkaller.appspotmail.com
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://lore.kernel.org/r/caabcf3fc87bdae970509b5ff32d05bb7ce2fb15.1616807117.git.skhan@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/usbip/vudc_dev.c | 1 | ||||
| -rw-r--r-- | drivers/usb/usbip/vudc_sysfs.c | 5 |
2 files changed, 6 insertions, 0 deletions
diff --git a/drivers/usb/usbip/vudc_dev.c b/drivers/usb/usbip/vudc_dev.c index c8eeabdd9b56..2bc428f2e261 100644 --- a/drivers/usb/usbip/vudc_dev.c +++ b/drivers/usb/usbip/vudc_dev.c @@ -572,6 +572,7 @@ static int init_vudc_hw(struct vudc *udc) init_waitqueue_head(&udc->tx_waitq); spin_lock_init(&ud->lock); + mutex_init(&ud->sysfs_lock); ud->status = SDEV_ST_AVAILABLE; ud->side = USBIP_VUDC; diff --git a/drivers/usb/usbip/vudc_sysfs.c b/drivers/usb/usbip/vudc_sysfs.c index 7383a543c6d1..f7633ee655a1 100644 --- a/drivers/usb/usbip/vudc_sysfs.c +++ b/drivers/usb/usbip/vudc_sysfs.c @@ -112,6 +112,7 @@ static ssize_t usbip_sockfd_store(struct device *dev, dev_err(dev, "no device"); return -ENODEV; } + mutex_lock(&udc->ud.sysfs_lock); spin_lock_irqsave(&udc->lock, flags); /* Don't export what we don't have */ if (!udc->driver || !udc->pullup) { @@ -187,6 +188,8 @@ static ssize_t usbip_sockfd_store(struct device *dev, wake_up_process(udc->ud.tcp_rx); wake_up_process(udc->ud.tcp_tx); + + mutex_unlock(&udc->ud.sysfs_lock); return count; } else { @@ -207,6 +210,7 @@ static ssize_t usbip_sockfd_store(struct device *dev, } spin_unlock_irqrestore(&udc->lock, flags); + mutex_unlock(&udc->ud.sysfs_lock); return count; @@ -216,6 +220,7 @@ unlock_ud: spin_unlock_irq(&udc->ud.lock); unlock: spin_unlock_irqrestore(&udc->lock, flags); + mutex_unlock(&udc->ud.sysfs_lock); return ret; } |