Commit graph

6 commits

Author SHA1 Message Date
Mauro Carvalho Chehab
224f0ed85c media: dvb_frontend: don't play tricks with underflow values
[ Upstream commit 9883a4d41aba7612644e9bb807b971247cea9b9d ]

fepriv->auto_sub_step is unsigned. Setting it to -1 is just a
trick to avoid calling continue, as reported by Coverity.

It relies to have this code just afterwards:

	if (!ready) fepriv->auto_sub_step++;

Simplify the code by simply setting it to zero and use
continue to return to the while loop.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-30 02:33:23 +01:00
Mauro Carvalho Chehab
7bfceb4f48 media: dvbdev: prevent the risk of out of memory access
[ Upstream commit 972e63e895abbe8aa1ccbdbb4e6362abda7cd457 ]

The dvbdev contains a static variable used to store dvb minors.

The behavior of it depends if CONFIG_DVB_DYNAMIC_MINORS is set
or not. When not set, dvb_register_device() won't check for
boundaries, as it will rely that a previous call to
dvb_register_adapter() would already be enforcing it.

On a similar way, dvb_device_open() uses the assumption
that the register functions already did the needed checks.

This can be fragile if some device ends using different
calls. This also generate warnings on static check analysers
like Coverity.

So, add explicit guards to prevent potential risk of OOM issues.

Fixes: 5dd3f3071070 ("V4L/DVB (9361): Dynamic DVB minor allocation")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-30 02:33:23 +01:00
Ricardo Ribalda
e8d59e07ee media: dvbdev: Initialize sbuf
[ Upstream commit 17d1316de0d7dc1bdc5d6e3ad4efd30a9bf1a381 ]

Because the size passed to copy_from_user() cannot be known beforehand,
it needs to be checked during runtime with check_object_size. That makes
gcc believe that the content of sbuf can be used before init.

Fix:
./include/linux/thread_info.h:215:17: warning: ‘sbuf’ may be used uninitialized [-Wmaybe-uninitialized]

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 14:19:32 +01:00
Zhipeng Lu
a0eab8dd81 media: edia: dvbdev: fix a use-after-free
[ Upstream commit 8c64f4cdf4e6cc5682c52523713af8c39c94e6d5 ]

In dvb_register_device, *pdvbdev is set equal to dvbdev, which is freed
in several error-handling paths. However, *pdvbdev is not set to NULL
after dvbdev's deallocation, causing use-after-frees in many places,
for example, in the following call chain:

budget_register
  |-> dvb_dmxdev_init
        |-> dvb_register_device
  |-> dvb_dmxdev_release
        |-> dvb_unregister_device
              |-> dvb_remove_device
                    |-> dvb_device_put
                          |-> kref_put

When calling dvb_unregister_device, dmxdev->dvbdev (i.e. *pdvbdev in
dvb_register_device) could point to memory that had been freed in
dvb_register_device. Thereafter, this pointer is transferred to
kref_put and triggering a use-after-free.

Link: https://lore.kernel.org/linux-media/20240203134046.3120099-1-alexious@zju.edu.cn
Fixes: b61901024776 ("V4L/DVB (5244): Dvbdev: fix illegal re-usage of fileoperations struct")
Signed-off-by: Zhipeng Lu <alexious@zju.edu.cn>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 08:44:52 +01:00
Dan Carpenter
46eff4c5db media: dvbdev: drop refcount on error path in dvb_device_open()
[ Upstream commit a2dd235df435a05d389240be748909ada91201d2 ]

If call to file->f_op->open() fails, then call dvb_device_put(dvbdev).

Fixes: 0fc044b2b5e2 ("media: dvbdev: adopts refcnt to avoid UAF")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 12:12:41 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00