diff options
| author | Chen Zhongjin <chenzhongjin@huawei.com> | 2022-11-08 10:06:30 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-01-14 12:15:30 +0300 |
| commit | 0369af6fe33d4053899b121b32e91f870b2cf0ae (patch) | |
| tree | 64b2f0949b8feb41ba4474c60854fb53b4cbf819 /drivers/media | |
| parent | 3afd738e7712473bf0d9a8ccb4b1092d59345f01 (diff) | |
| download | linux-0369af6fe33d4053899b121b32e91f870b2cf0ae.tar.xz | |
media: vidtv: Fix use-after-free in vidtv_bridge_dvb_init()
[ Upstream commit ba8d9405935097e296bcf7a942c3a01df0edb865 ]
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: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/media')
| -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 fc64d0c8492a..3c281265a9ec 100644 --- a/drivers/media/test-drivers/vidtv/vidtv_bridge.c +++ b/drivers/media/test-drivers/vidtv/vidtv_bridge.c @@ -456,26 +456,20 @@ 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); |