diff options
| author | Oliver Neukum <oneukum@suse.com> | 2020-09-17 13:34:27 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-09-23 13:11:01 +0300 |
| commit | 51e7ea12ccedbed2f9e31b593d02432986e491fb (patch) | |
| tree | 9e289d0f0f440aa9bb5b2677a729317a0bb83f5f | |
| parent | 1f4b55978ea2ce37d0730515ef9f12b01c2c557b (diff) | |
| download | linux-51e7ea12ccedbed2f9e31b593d02432986e491fb.tar.xz | |
usblp: fix race between disconnect() and read()
commit 9cdabcb3ef8c24ca3a456e4db7b012befb688e73 upstream.
read() needs to check whether the device has been
disconnected before it tries to talk to the device.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Reported-by: syzbot+be5b5f86a162a6c281e6@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/20200917103427.15740-1-oneukum@suse.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/class/usblp.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/usb/class/usblp.c b/drivers/usb/class/usblp.c index 419804c9c974..db36a796af8c 100644 --- a/drivers/usb/class/usblp.c +++ b/drivers/usb/class/usblp.c @@ -827,6 +827,11 @@ static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, lo if (rv < 0) return rv; + if (!usblp->present) { + count = -ENODEV; + goto done; + } + if ((avail = usblp->rstatus) < 0) { printk(KERN_ERR "usblp%d: error %d reading from printer\n", usblp->minor, (int)avail); |