Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1Testing for regressions in Media Controller API register, ioctl, syscall,
2and unregister paths. There have a few problems that result in use-after
3free on media_device, media_devnode, and cdev pointers when the driver is
4unbound while ioctl is in progress.
5
6Test Procedure:
7
8Run bin/unbind loop while ioctls are in progress.
9Run rmmod and modprobe.
10Disconnect the device.
11
12Setup:
13
14Build media_device_test
15cd tools/testing/selftests/media_tests
16make
17
18Regressions test for cdev use-after-free error on /dev/mediaX when driver
19is unbound:
20
21Start media_device_test to regression test media devnode dynamic alloc
22and cdev use-after-free fixes. This opens media dev files and sits in
23a loop running media ioctl MEDIA_IOC_DEVICE_INFO command once every 10
24seconds. The idea is when device file goes away, media devnode and cdev
25should stick around until this test exits.
26
27The test for a random number of iterations or until user kills it with a
28sleep 10 in between the ioctl calls.
29
30sudo ./media_device_test -d /dev/mediaX
31
32Regression test for media_devnode unregister race with ioctl_syscall:
33
34Start 6 open_loop_test.sh tests with different /dev/mediaX files. When
35device file goes away after unbind, device file name changes. Start the
36test with possible device names. If we start with /dev/media0 for example,
37after unbind, /dev/media1 or /dev/media2 could get created. The idea is
38keep ioctls going while bind/unbind runs.
39
40Copy bind_unbind_sample.txt and make changes to specify the driver name
41and number to run bind and unbind. Start the bind_unbind.sh
42
43Run dmesg looking for any use-after-free errors or mutex lock errors.