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| author | Shuah Khan <skhan@linuxfoundation.org> | 2021-03-29 19:36:50 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-04-14 08:22:33 +0200 |
| commit | 98671cffee7f988e4d8a9764e818cd8bf57e9b69 (patch) | |
| tree | 6b9f276a2fc3091ca57c37c576c21f23abcd3cdd | |
| parent | dcc23b41c2b84358cb4aabf99d0a5cf83754435b (diff) | |
| download | linux-stable-98671cffee7f988e4d8a9764e818cd8bf57e9b69.tar.gz linux-stable-98671cffee7f988e4d8a9764e818cd8bf57e9b69.tar.bz2 linux-stable-98671cffee7f988e4d8a9764e818cd8bf57e9b69.zip | |
usbip: vudc synchronize sysfs code paths
commit bd8b82042269a95db48074b8bb400678dbac1815 upstream.
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 1634d8698e15..74568325d8c0 100644 --- a/drivers/usb/usbip/vudc_dev.c +++ b/drivers/usb/usbip/vudc_dev.c @@ -571,6 +571,7 @@ 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 1bde09e5cb47..de2babadd146 100644 --- a/drivers/usb/usbip/vudc_sysfs.c +++ b/drivers/usb/usbip/vudc_sysfs.c @@ -113,6 +113,7 @@ 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) { @@ -188,6 +189,8 @@ 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 { @@ -208,6 +211,7 @@ static ssize_t usbip_sockfd_store(struct device *dev, } spin_unlock_irqrestore(&udc->lock, flags); + mutex_unlock(&udc->ud.sysfs_lock); return count; @@ -217,6 +221,7 @@ unlock_ud: spin_unlock_irq(&udc->ud.lock); unlock: spin_unlock_irqrestore(&udc->lock, flags); + mutex_unlock(&udc->ud.sysfs_lock); return ret; } |