From 03f36e885fc26cb0ea299fb6df5171a51e814548 Mon Sep 17 00:00:00 2001 From: Oliver Neukum Date: Thu, 25 Oct 2007 15:46:30 +0200 Subject: [PATCH] USB: open disconnect race in iowarrior the driver sets intfdata to NULL without lock. Data structures can be freed and accessed. Signed-off-by: Oliver Neukum Signed-off-by: Greg Kroah-Hartman --- drivers/usb/misc/iowarrior.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/usb/misc/iowarrior.c b/drivers/usb/misc/iowarrior.c index c86c132d8a..764696ff1e 100644 --- a/drivers/usb/misc/iowarrior.c +++ b/drivers/usb/misc/iowarrior.c @@ -66,6 +66,7 @@ module_param(debug, bool, 0644); MODULE_PARM_DESC(debug, "debug=1 enables debugging messages"); static struct usb_driver iowarrior_driver; +static DEFINE_MUTEX(iowarrior_open_disc_lock); /*--------------*/ /* data */ @@ -608,11 +609,15 @@ static int iowarrior_open(struct inode *inode, struct file *file) return -ENODEV; } + mutex_lock(&iowarrior_open_disc_lock); dev = usb_get_intfdata(interface); - if (!dev) + if (!dev) { + mutex_unlock(&iowarrior_open_disc_lock); return -ENODEV; + } mutex_lock(&dev->mutex); + mutex_unlock(&iowarrior_open_disc_lock); /* Only one process can open each device, no sharing. */ if (dev->opened) { @@ -866,6 +871,7 @@ static void iowarrior_disconnect(struct usb_interface *interface) int minor; dev = usb_get_intfdata(interface); + mutex_lock(&iowarrior_open_disc_lock); usb_set_intfdata(interface, NULL); minor = dev->minor; @@ -879,6 +885,7 @@ static void iowarrior_disconnect(struct usb_interface *interface) dev->present = 0; mutex_unlock(&dev->mutex); + mutex_unlock(&iowarrior_open_disc_lock); if (dev->opened) { /* There is a process that holds a filedescriptor to the device , -- 2.39.5