blob: b48c314523c1d1bb0ac30c201aaa23a361ab752b [file] [log] [blame]
From 54a3e998b1b7522de68a9caed3e3d500eff13c86 Mon Sep 17 00:00:00 2001
From: Sriharsha Allenki <>
Date: Thu, 26 Mar 2020 17:26:20 +0530
Subject: [PATCH] usb: gadget: f_fs: Fix use after free issue as part of queue
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 <>
CC: stable <>
Reviewed-by: Peter Chen <>
Signed-off-by: Greg Kroah-Hartman <>
Signed-off-by: Paul Gortmaker <>
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 265e3e523ef3..fbde4c0709a7 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -1119,6 +1119,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
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;