diff options
author | Chen Zhongjin <chenzhongjin@huawei.com> | 2022-11-08 10:06:30 +0300 |
---|---|---|
committer | Mauro Carvalho Chehab <mchehab@kernel.org> | 2022-11-25 10:33:14 +0300 |
commit | 675807dee3e9e3b17ebe140085b3d78b7adc1a31 (patch) | |
tree | 10d75d6cfb327033b53cf96ba8426b269f8f0eca /drivers/media/test-drivers/vidtv/vidtv_bridge.c | |
parent | 645e71337e1c31795f48f18dd62202a001101a85 (diff) | |
download | linux-675807dee3e9e3b17ebe140085b3d78b7adc1a31.tar.xz |
media: vidtv: Fix use-after-free in vidtv_bridge_dvb_init()
KASAN reports a use-after-free:
BUG: KASAN: use-after-free in dvb_dmxdev_release+0x4d5/0x5d0 [dvb_core]
Call Trace:
...
dvb_dmxdev_release+0x4d5/0x5d0 [dvb_core]
vidtv_bridge_probe+0x7bf/0xa40 [dvb_vidtv_bridge]
platform_probe+0xb6/0x170
...
Allocated by task 1238:
...
dvb_register_device+0x1a7/0xa70 [dvb_core]
dvb_dmxdev_init+0x2af/0x4a0 [dvb_core]
vidtv_bridge_probe+0x766/0xa40 [dvb_vidtv_bridge]
...
Freed by task 1238:
dvb_register_device+0x6d2/0xa70 [dvb_core]
dvb_dmxdev_init+0x2af/0x4a0 [dvb_core]
vidtv_bridge_probe+0x766/0xa40 [dvb_vidtv_bridge]
...
It is because the error handling in vidtv_bridge_dvb_init() is wrong.
First, vidtv_bridge_dmx(dev)_init() will clean themselves when fail, but
goto fail_dmx(_dev): calls release functions again, which causes
use-after-free.
Also, in fail_fe, fail_tuner_probe and fail_demod_probe, j = i will cause
out-of-bound when i finished its loop (i == NUM_FE). And the loop
releasing is wrong, although now NUM_FE is 1 so it won't cause problem.
Fix this by correctly releasing everything.
Fixes: f90cf6079bf6 ("media: vidtv: add a bridge driver")
Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Diffstat (limited to 'drivers/media/test-drivers/vidtv/vidtv_bridge.c')
-rw-r--r-- | drivers/media/test-drivers/vidtv/vidtv_bridge.c | 22 |
1 files changed, 8 insertions, 14 deletions
diff --git a/drivers/media/test-drivers/vidtv/vidtv_bridge.c b/drivers/media/test-drivers/vidtv/vidtv_bridge.c index 82620613d56b..dff7265a42ca 100644 --- a/drivers/media/test-drivers/vidtv/vidtv_bridge.c +++ b/drivers/media/test-drivers/vidtv/vidtv_bridge.c @@ -459,26 +459,20 @@ fail_dmx_conn: for (j = j - 1; j >= 0; --j) dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->dmx_fe[j]); -fail_dmx_dev: dvb_dmxdev_release(&dvb->dmx_dev); -fail_dmx: +fail_dmx_dev: dvb_dmx_release(&dvb->demux); +fail_dmx: +fail_demod_probe: + for (i = i - 1; i >= 0; --i) { + dvb_unregister_frontend(dvb->fe[i]); fail_fe: - for (j = i; j >= 0; --j) - dvb_unregister_frontend(dvb->fe[j]); + dvb_module_release(dvb->i2c_client_tuner[i]); fail_tuner_probe: - for (j = i; j >= 0; --j) - if (dvb->i2c_client_tuner[j]) - dvb_module_release(dvb->i2c_client_tuner[j]); - -fail_demod_probe: - for (j = i; j >= 0; --j) - if (dvb->i2c_client_demod[j]) - dvb_module_release(dvb->i2c_client_demod[j]); - + dvb_module_release(dvb->i2c_client_demod[i]); + } fail_adapter: dvb_unregister_adapter(&dvb->adapter); - fail_i2c: i2c_del_adapter(&dvb->i2c_adapter); |