4.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
[ Upstream commit f019f07ecf6a6b8bd6d7853bce70925d90af02d1 ]
The uio_unregister_device() function assumes that if "info->uio_dev" is
non-NULL that means "info" is fully allocated. Setting info->uio_de
has to be the last thing in the function.
In the current code, if request_threaded_irq() fails then we return with
info->uio_dev set to non-NULL but info is not fully allocated and it can
lead to double frees.
Fixes: beafc54c4e2f ("UIO: Add the User IO core code")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/uio/uio.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
--- a/drivers/uio/uio.c
+++ b/drivers/uio/uio.c
@@ -955,8 +955,6 @@ int __uio_register_device(struct module
if (ret)
goto err_uio_dev_add_attributes;
- info->uio_dev = idev;
-
if (info->irq && (info->irq != UIO_IRQ_CUSTOM)) {
/*
* Note that we deliberately don't use devm_request_irq
@@ -972,6 +970,7 @@ int __uio_register_device(struct module
goto err_request_irq;
}
+ info->uio_dev = idev;
return 0;
err_request_irq:
