path: root/include
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authorOliver Neukum <oneukum@suse.de>2014-03-26 14:32:51 +0100
committerDavid S. Miller <davem@davemloft.net>2014-03-27 14:59:10 -0400
commit14a0d635d18d0fb552dcc979d6d25106e6541f2e (patch)
tree2fa1bce86903a0f841ab662eb85de4445bbfe398 /include
parent681daee2443291419c57cccb0671f5f94a839005 (diff)
usbnet: include wait queue head in device structure
This fixes a race which happens by freeing an object on the stack. Quoting Julius: > The issue is > that it calls usbnet_terminate_urbs() before that, which temporarily > installs a waitqueue in dev->wait in order to be able to wait on the > tasklet to run and finish up some queues. The waiting itself looks > okay, but the access to 'dev->wait' is totally unprotected and can > race arbitrarily. I think in this case usbnet_bh() managed to succeed > it's dev->wait check just before usbnet_terminate_urbs() sets it back > to NULL. The latter then finishes and the waitqueue_t structure on its > stack gets overwritten by other functions halfway through the > wake_up() call in usbnet_bh(). The fix is to just not allocate the data structure on the stack. As dev->wait is abused as a flag it also takes a runtime PM change to fix this bug. Signed-off-by: Oliver Neukum <oneukum@suse.de> Reported-by: Grant Grundler <grundler@google.com> Tested-by: Grant Grundler <grundler@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
1 files changed, 1 insertions, 1 deletions
diff --git a/include/linux/usb/usbnet.h b/include/linux/usb/usbnet.h
index e303eef94dd5..0662e98fef72 100644
--- a/include/linux/usb/usbnet.h
+++ b/include/linux/usb/usbnet.h
@@ -30,7 +30,7 @@ struct usbnet {
struct driver_info *driver_info;
const char *driver_name;
void *driver_priv;
- wait_queue_head_t *wait;
+ wait_queue_head_t wait;
struct mutex phy_mutex;
unsigned char suspend_count;
unsigned char pkt_cnt, pkt_err;