mirror of
https://github.com/Divested-Mobile/DivestOS-Build.git
synced 2024-12-24 06:59:27 -05:00
52 lines
1.9 KiB
Diff
52 lines
1.9 KiB
Diff
From 38740a5b87d53ceb89eb2c970150f6e94e00373a Mon Sep 17 00:00:00 2001
|
|
From: Lars-Peter Clausen <lars@metafoo.de>
|
|
Date: Thu, 14 Apr 2016 17:01:17 +0200
|
|
Subject: usb: gadget: f_fs: Fix use-after-free
|
|
|
|
When using asynchronous read or write operations on the USB endpoints the
|
|
issuer of the IO request is notified by calling the ki_complete() callback
|
|
of the submitted kiocb when the URB has been completed.
|
|
|
|
Calling this ki_complete() callback will free kiocb. Make sure that the
|
|
structure is no longer accessed beyond that point, otherwise undefined
|
|
behaviour might occur.
|
|
|
|
Fixes: 2e4c7553cd6f ("usb: gadget: f_fs: add aio support")
|
|
Cc: <stable@vger.kernel.org> # v3.15+
|
|
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
|
|
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
|
|
---
|
|
drivers/usb/gadget/function/f_fs.c | 5 ++---
|
|
1 file changed, 2 insertions(+), 3 deletions(-)
|
|
|
|
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
|
|
index e21ca2bd..15b648c 100644
|
|
--- a/drivers/usb/gadget/function/f_fs.c
|
|
+++ b/drivers/usb/gadget/function/f_fs.c
|
|
@@ -646,6 +646,7 @@ static void ffs_user_copy_worker(struct work_struct *work)
|
|
work);
|
|
int ret = io_data->req->status ? io_data->req->status :
|
|
io_data->req->actual;
|
|
+ bool kiocb_has_eventfd = io_data->kiocb->ki_flags & IOCB_EVENTFD;
|
|
|
|
if (io_data->read && ret > 0) {
|
|
use_mm(io_data->mm);
|
|
@@ -657,13 +658,11 @@ static void ffs_user_copy_worker(struct work_struct *work)
|
|
|
|
io_data->kiocb->ki_complete(io_data->kiocb, ret, ret);
|
|
|
|
- if (io_data->ffs->ffs_eventfd &&
|
|
- !(io_data->kiocb->ki_flags & IOCB_EVENTFD))
|
|
+ if (io_data->ffs->ffs_eventfd && !kiocb_has_eventfd)
|
|
eventfd_signal(io_data->ffs->ffs_eventfd, 1);
|
|
|
|
usb_ep_free_request(io_data->ep, io_data->req);
|
|
|
|
- io_data->kiocb->private = NULL;
|
|
if (io_data->read)
|
|
kfree(io_data->to_free);
|
|
kfree(io_data->buf);
|
|
--
|
|
cgit v1.1
|
|
|