USB: gadget: f_mass_storage: fix in error recovery

In to places in fsg_common_init() an unconditional call to kfree()
on common was performed in error recovery which is not a valid
behaviour since fsg_common structure is not always allocated by
fsg_common_init().

To fix, the calls has been replaced with a goto to a proper error
recovery which does the correct thing.

Also, refactored fsg_common_release() function.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Reviewed-by: Viral Mehta <viral.mehta@lntinfotech.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Michal Nazarewicz 2010-05-12 12:51:13 +02:00 committed by Greg Kroah-Hartman
parent f537da685c
commit b9e000884e

View file

@ -2742,10 +2742,8 @@ static struct fsg_common *fsg_common_init(struct fsg_common *common,
/* Maybe allocate device-global string IDs, and patch descriptors */
if (fsg_strings[FSG_STRING_INTERFACE].id == 0) {
rc = usb_string_id(cdev);
if (rc < 0) {
kfree(common);
return ERR_PTR(rc);
}
if (unlikely(rc < 0))
goto error_release;
fsg_strings[FSG_STRING_INTERFACE].id = rc;
fsg_intf_desc.iInterface = rc;
}
@ -2753,9 +2751,9 @@ static struct fsg_common *fsg_common_init(struct fsg_common *common,
/* Create the LUNs, open their backing files, and register the
* LUN devices in sysfs. */
curlun = kzalloc(nluns * sizeof *curlun, GFP_KERNEL);
if (!curlun) {
kfree(common);
return ERR_PTR(-ENOMEM);
if (unlikely(!curlun)) {
rc = -ENOMEM;
goto error_release;
}
common->luns = curlun;
@ -2914,11 +2912,7 @@ static struct fsg_common *fsg_common_init(struct fsg_common *common,
static void fsg_common_release(struct kref *ref)
{
struct fsg_common *common =
container_of(ref, struct fsg_common, ref);
unsigned i = common->nluns;
struct fsg_lun *lun = common->luns;
struct fsg_buffhd *bh;
struct fsg_common *common = container_of(ref, struct fsg_common, ref);
/* If the thread isn't already dead, tell it to exit now */
if (common->state != FSG_STATE_TERMINATED) {
@ -2929,23 +2923,28 @@ static void fsg_common_release(struct kref *ref)
complete(&common->thread_notifier);
}
/* Beware tempting for -> do-while optimization: when in error
* recovery nluns may be zero. */
if (likely(common->luns)) {
struct fsg_lun *lun = common->luns;
unsigned i = common->nluns;
for (; i; --i, ++lun) {
device_remove_file(&lun->dev, &dev_attr_ro);
device_remove_file(&lun->dev, &dev_attr_file);
fsg_lun_close(lun);
device_unregister(&lun->dev);
/* In error recovery common->nluns may be zero. */
for (; i; --i, ++lun) {
device_remove_file(&lun->dev, &dev_attr_ro);
device_remove_file(&lun->dev, &dev_attr_file);
fsg_lun_close(lun);
device_unregister(&lun->dev);
}
kfree(common->luns);
}
kfree(common->luns);
i = FSG_NUM_BUFFERS;
bh = common->buffhds;
do {
kfree(bh->buf);
} while (++bh, --i);
{
struct fsg_buffhd *bh = common->buffhds;
unsigned i = FSG_NUM_BUFFERS;
do {
kfree(bh->buf);
} while (++bh, --i);
}
if (common->free_storage_on_release)
kfree(common);