uas: Fix memory management
The scsi-host structure is refcounted, scsi_remove_host tears down the
scsi-host but does not decrement the refcount, so we need to call
scsi_put_host on disconnect to get the underlying memory to be freed.
After calling scsi_remove_host, the scsi-core may still hold a reference to
the scsi-host, iow we may still get called after uas_disconnect, but we
do our own life cycle management of uas_devinfo, freeing it on disconnect,
and thus may end up using devinfo after it has been freed. Switch to letting
scsi_host_alloc allocate and manage the memory for us.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
index 8c68580..d81d041 100644
--- a/drivers/usb/storage/uas.c
+++ b/drivers/usb/storage/uas.c
@@ -315,7 +315,7 @@
{
struct iu *iu = urb->transfer_buffer;
struct Scsi_Host *shost = urb->context;
- struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
+ struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
struct scsi_cmnd *cmnd;
struct uas_cmd_info *cmdinfo;
unsigned long flags;
@@ -562,7 +562,7 @@
static struct urb *uas_submit_sense_urb(struct Scsi_Host *shost,
gfp_t gfp, unsigned int stream)
{
- struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
+ struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
struct urb *urb;
urb = uas_alloc_sense_urb(devinfo, gfp, shost, stream);
@@ -734,7 +734,7 @@
const char *fname, u8 function)
{
struct Scsi_Host *shost = cmnd->device->host;
- struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
+ struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
u16 tag = devinfo->qdepth;
unsigned long flags;
struct urb *sense_urb;
@@ -879,7 +879,7 @@
static int uas_slave_alloc(struct scsi_device *sdev)
{
- sdev->hostdata = (void *)sdev->host->hostdata[0];
+ sdev->hostdata = (void *)sdev->host->hostdata;
return 0;
}
@@ -1005,11 +1005,8 @@
if (uas_switch_interface(udev, intf))
return -ENODEV;
- devinfo = kmalloc(sizeof(struct uas_dev_info), GFP_KERNEL);
- if (!devinfo)
- goto set_alt0;
-
- shost = scsi_host_alloc(&uas_host_template, sizeof(void *));
+ shost = scsi_host_alloc(&uas_host_template,
+ sizeof(struct uas_dev_info));
if (!shost)
goto set_alt0;
@@ -1019,6 +1016,7 @@
shost->max_channel = 0;
shost->sg_tablesize = udev->bus->sg_tablesize;
+ devinfo = (struct uas_dev_info *)shost->hostdata;
devinfo->intf = intf;
devinfo->udev = udev;
devinfo->resetting = 0;
@@ -1044,8 +1042,6 @@
if (result)
goto free_streams;
- shost->hostdata[0] = (unsigned long)devinfo;
-
scsi_scan_host(shost);
usb_set_intfdata(intf, shost);
return result;
@@ -1054,7 +1050,6 @@
uas_free_streams(devinfo);
set_alt0:
usb_set_interface(udev, intf->altsetting[0].desc.bInterfaceNumber, 0);
- kfree(devinfo);
if (shost)
scsi_host_put(shost);
return result;
@@ -1063,7 +1058,7 @@
static int uas_pre_reset(struct usb_interface *intf)
{
struct Scsi_Host *shost = usb_get_intfdata(intf);
- struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
+ struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
unsigned long flags;
if (devinfo->shutdown)
@@ -1089,7 +1084,7 @@
static int uas_post_reset(struct usb_interface *intf)
{
struct Scsi_Host *shost = usb_get_intfdata(intf);
- struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
+ struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
unsigned long flags;
if (devinfo->shutdown)
@@ -1113,7 +1108,7 @@
static int uas_suspend(struct usb_interface *intf, pm_message_t message)
{
struct Scsi_Host *shost = usb_get_intfdata(intf);
- struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
+ struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
/* Wait for any pending requests to complete */
flush_work(&devinfo->work);
@@ -1133,7 +1128,7 @@
static int uas_reset_resume(struct usb_interface *intf)
{
struct Scsi_Host *shost = usb_get_intfdata(intf);
- struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
+ struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
unsigned long flags;
if (uas_configure_endpoints(devinfo) != 0) {
@@ -1152,7 +1147,7 @@
static void uas_disconnect(struct usb_interface *intf)
{
struct Scsi_Host *shost = usb_get_intfdata(intf);
- struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
+ struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
devinfo->resetting = 1;
cancel_work_sync(&devinfo->work);
@@ -1163,7 +1158,7 @@
uas_zap_dead(devinfo);
scsi_remove_host(shost);
uas_free_streams(devinfo);
- kfree(devinfo);
+ scsi_host_put(shost);
}
/*
@@ -1176,7 +1171,7 @@
struct usb_interface *intf = to_usb_interface(dev);
struct usb_device *udev = interface_to_usbdev(intf);
struct Scsi_Host *shost = usb_get_intfdata(intf);
- struct uas_dev_info *devinfo = (void *)shost->hostdata[0];
+ struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
if (system_state != SYSTEM_RESTART)
return;
