linux/drivers/greybus
Sicong Huang 74cd0a4218 greybus: Fix use-after-free bug in gb_interface_release due to race condition.
commit 5c9c5d7f26 upstream.

In gb_interface_create, &intf->mode_switch_completion is bound with
gb_interface_mode_switch_work. Then it will be started by
gb_interface_request_mode_switch. Here is the relevant code.
if (!queue_work(system_long_wq, &intf->mode_switch_work)) {
	...
}

If we call gb_interface_release to make cleanup, there may be an
unfinished work. This function will call kfree to free the object
"intf". However, if gb_interface_mode_switch_work is scheduled to
run after kfree, it may cause use-after-free error as
gb_interface_mode_switch_work will use the object "intf".
The possible execution flow that may lead to the issue is as follows:

CPU0                            CPU1

                            |   gb_interface_create
                            |   gb_interface_request_mode_switch
gb_interface_release        |
kfree(intf) (free)          |
                            |   gb_interface_mode_switch_work
                            |   mutex_lock(&intf->mutex) (use)

Fix it by canceling the work before kfree.

Signed-off-by: Sicong Huang <congei42@163.com>
Link: https://lore.kernel.org/r/20240416080313.92306-1-congei42@163.com
Cc: Ronnie Sahlberg <rsahlberg@ciq.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05 09:08:20 +02:00
..
arpc.h
bundle.c
connection.c
control.c
core.c
debugfs.c
es2.c
greybus_trace.h
hd.c
interface.c greybus: Fix use-after-free bug in gb_interface_release due to race condition. 2024-07-05 09:08:20 +02:00
Kconfig
Makefile
manifest.c
module.c
operation.c
svc_watchdog.c
svc.c greybus: svc: fix an error handling bug in gb_svc_hello() 2022-04-15 14:17:58 +02:00