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uas: Fix memory management

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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>
This commit is contained in:
Hans de Goede 2013-11-13 09:32:22 +01:00 committed by Sarah Sharp
parent c6f63207a3
commit 21fc05b680
1 changed files with 14 additions and 19 deletions
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33
drivers/usb/storage/uas.c
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@ -315,7 +315,7 @@ static void uas_stat_cmplt(struct urb *urb)
{
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 @@ err:
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 @@ static int uas_eh_task_mgmt(struct scsi_cmnd *cmnd,
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_eh_bus_reset_handler(struct scsi_cmnd *cmnd)
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 @@ static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
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 @@ static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
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 @@ static int uas_probe(struct usb_interface *intf, const struct usb_device_id *id)
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 @@ free_streams:
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 @@ set_alt0:
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_pre_reset(struct usb_interface *intf)
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_post_reset(struct usb_interface *intf)
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_resume(struct usb_interface *intf)
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 int uas_reset_resume(struct usb_interface *intf)
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 @@ static void uas_disconnect(struct usb_interface *intf)
uas_zap_dead(devinfo);
scsi_remove_host(shost);
uas_free_streams(devinfo);
kfree(devinfo);
scsi_host_put(shost);
}
/*
@ -1176,7 +1171,7 @@ static void uas_shutdown(struct device *dev)
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;