lkml.org 
[lkml]   [2020]   [Apr]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 5.5 085/257] usb: gadget: f_fs: Fix use after free issue as part of queue failure
Date
From: Sriharsha Allenki <sallenki@codeaurora.org>

commit f63ec55ff904b2f2e126884fcad93175f16ab4bb upstream.

In AIO case, the request is freed up if ep_queue fails.
However, io_data->req still has the reference to this freed
request. In the case of this failure if there is aio_cancel
call on this io_data it will lead to an invalid dequeue
operation and a potential use after free issue.
Fix this by setting the io_data->req to NULL when the request
is freed as part of queue failure.

Fixes: 2e4c7553cd6f ("usb: gadget: f_fs: add aio support")
Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>
CC: stable <stable@vger.kernel.org>
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Link: https://lore.kernel.org/r/20200326115620.12571-1-sallenki@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/gadget/function/f_fs.c | 1 +
1 file changed, 1 insertion(+)

--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -1120,6 +1120,7 @@ static ssize_t ffs_epfile_io(struct file

ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
if (unlikely(ret)) {
+ io_data->req = NULL;
usb_ep_free_request(ep->ep, req);
goto error_lock;
}

\
 
 \ /
  Last update: 2020-04-16 17:47    [W:0.853 / U:0.156 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site