diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2015-02-06 02:07:45 -0500 |
|---|---|---|
| committer | Sasha Levin <sasha.levin@oracle.com> | 2015-03-28 10:01:39 -0400 |
| commit | c81fc59be42c6e0d5061d00ee910c59db08da90e (patch) | |
| tree | 255d1fd5e0bf4fe3f88c0393c699ec563fd2d9ca /drivers | |
| parent | c7fd1867c7d0626bf00373cec0f64b0ce4f4ec84 (diff) | |
gadgetfs: use-after-free in ->aio_read()
[ Upstream commit f01d35a15fa04162a58b95970fc01fa70ec9dacd ]
AIO_PREAD requests call ->aio_read() with iovec on caller's stack, so if
we are going to access it asynchronously, we'd better get ourselves
a copy - the one on kernel stack of aio_run_iocb() won't be there
anymore. function/f_fs.c take care of doing that, legacy/inode.c
doesn't...
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/usb/gadget/legacy/inode.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/drivers/usb/gadget/legacy/inode.c b/drivers/usb/gadget/legacy/inode.c index 08048613eed6..db2becd31a51 100644 --- a/drivers/usb/gadget/legacy/inode.c +++ b/drivers/usb/gadget/legacy/inode.c @@ -565,7 +565,6 @@ static ssize_t ep_copy_to_user(struct kiocb_priv *priv) if (total == 0) break; } - return len; } @@ -584,6 +583,7 @@ static void ep_user_copy_worker(struct work_struct *work) aio_complete(iocb, ret, ret); kfree(priv->buf); + kfree(priv->iv); kfree(priv); } @@ -604,6 +604,7 @@ static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req) */ if (priv->iv == NULL || unlikely(req->actual == 0)) { kfree(req->buf); + kfree(priv->iv); kfree(priv); iocb->private = NULL; /* aio_complete() reports bytes-transferred _and_ faults */ @@ -639,7 +640,7 @@ ep_aio_rwtail( struct usb_request *req; ssize_t value; - priv = kmalloc(sizeof *priv, GFP_KERNEL); + priv = kzalloc(sizeof *priv, GFP_KERNEL); if (!priv) { value = -ENOMEM; fail: @@ -648,7 +649,14 @@ fail: } iocb->private = priv; priv->iocb = iocb; - priv->iv = iv; + if (iv) { + priv->iv = kmemdup(iv, nr_segs * sizeof(struct iovec), + GFP_KERNEL); + if (!priv->iv) { + kfree(priv); + goto fail; + } + } priv->nr_segs = nr_segs; INIT_WORK(&priv->work, ep_user_copy_worker); @@ -688,6 +696,7 @@ fail: mutex_unlock(&epdata->lock); if (unlikely(value)) { + kfree(priv->iv); kfree(priv); put_ep(epdata); } else |