kernel/git/stable/linux-stable.git/drivers/media, branch linux-6.19.y

media: hackrf: fix to not free memory after the device is registered in hackrf_probe()

2026-04-22T11:30:52+00:00

commit 3b7da2b4d0fe014eff181ed37e3bf832eb8ed258 upstream. In hackrf driver, the following race condition occurs: ``` CPU0 CPU1 hackrf_probe() kzalloc(); // alloc hackrf_dev .... v4l2_device_register(); .... fd = sys_open("/path/to/dev"); // open hackrf fd .... v4l2_device_unregister(); .... kfree(); // free hackrf_dev .... sys_ioctl(fd, ...); v4l2_ioctl(); video_is_registered() // UAF!! .... sys_close(fd); v4l2_release() // UAF!! hackrf_video_release() kfree(); // DFB!! ``` When a V4L2 or video device is unregistered, the device node is removed so new open() calls are blocked. However, file descriptors that are already open-and any in-flight I/O-do not terminate immediately; they remain valid until the last reference is dropped and the driver's release() is invoked. Therefore, freeing device memory on the error path after hackrf_probe() has registered dev it will lead to a race to use-after-free vuln, since those already-open handles haven't been released yet. And since release() free memory too, race to use-after-free and double-free vuln occur. To prevent this, if device is registered from probe(), it should be modified to free memory only through release() rather than calling kfree() directly. Cc: Reported-by: syzbot+6ffd76b5405c006a46b7@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=6ffd76b5405c006a46b7 Reported-by: syzbot+f1b20958f93d2d250727@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=f1b20958f93d2d250727 Fixes: 8bc4a9ed8504 ("[media] hackrf: add support for transmitter") Signed-off-by: Jeongjun Park Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman

media: vidtv: fix pass-by-value structs causing MSAN warnings

2026-04-22T11:30:52+00:00

commit 5f8e73bde67e931468bc2a1860d78d72f0c6ba41 upstream. vidtv_ts_null_write_into() and vidtv_ts_pcr_write_into() take their argument structs by value, causing MSAN to report uninit-value warnings. While only vidtv_ts_null_write_into() has triggered a report so far, both functions share the same issue. Fix by passing both structs by const pointer instead, avoiding the stack copy of the struct along with its MSAN shadow and origin metadata. The functions do not modify the structs, which is enforced by the const qualifier. Fixes: f90cf6079bf67 ("media: vidtv: add a bridge driver") Cc: stable@vger.kernel.org Reported-by: syzbot+96f901260a0b2d29cd1a@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=96f901260a0b2d29cd1a Tested-by: syzbot+96f901260a0b2d29cd1a@syzkaller.appspotmail.com Suggested-by: Yihan Ding Signed-off-by: Abd-Alrhman Masalkhi Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman

media: as102: fix to not free memory after the device is registered in as102_usb_probe()

2026-04-22T11:30:52+00:00

commit 8bd29dbe03fc5b0f039ab2395ff37b64236d2f0c upstream. In as102_usb driver, the following race condition occurs: ``` CPU0 CPU1 as102_usb_probe() kzalloc(); // alloc as102_dev_t .... usb_register_dev(); fd = sys_open("/path/to/dev"); // open as102 fd .... usb_deregister_dev(); .... kfree(); // free as102_dev_t .... sys_close(fd); as102_release() // UAF!! as102_usb_release() kfree(); // DFB!! ``` When a USB character device registered with usb_register_dev() is later unregistered (via usb_deregister_dev() or disconnect), the device node is removed so new open() calls fail. However, file descriptors that are already open do not go away immediately: they remain valid until the last reference is dropped and the driver's .release() is invoked. In as102, as102_usb_probe() calls usb_register_dev() and then, on an error path, does usb_deregister_dev() and frees as102_dev_t right away. If userspace raced a successful open() before the deregistration, that open FD will later hit as102_release() --> as102_usb_release() and access or free as102_dev_t again, occur a race to use-after-free and double-free vuln. The fix is to never kfree(as102_dev_t) directly once usb_register_dev() has succeeded. After deregistration, defer freeing memory to .release(). In other words, let release() perform the last kfree when the final open FD is closed. Cc: Reported-by: syzbot+47321e8fd5a4c84088db@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=47321e8fd5a4c84088db Fixes: cd19f7d3e39b ("[media] as102: fix leaks at failure paths in as102_usb_probe()") Signed-off-by: Jeongjun Park Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman

media: em28xx: fix use-after-free in em28xx_v4l2_open()

2026-04-22T11:30:51+00:00

commit a66485a934c7187ae8e36517d40615fa2e961cff upstream. em28xx_v4l2_open() reads dev->v4l2 without holding dev->lock, creating a race with em28xx_v4l2_init()'s error path and em28xx_v4l2_fini(), both of which free the em28xx_v4l2 struct and set dev->v4l2 to NULL under dev->lock. This race leads to two issues: - use-after-free in v4l2_fh_init() when accessing vdev->ctrl_handler, since the video_device is embedded in the freed em28xx_v4l2 struct. - NULL pointer dereference in em28xx_resolution_set() when accessing v4l2->norm, since dev->v4l2 has been set to NULL. Fix this by moving the mutex_lock() before the dev->v4l2 read and adding a NULL check for dev->v4l2 under the lock. Reported-by: syzbot+c025d34b8eaa54c571b8@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=c025d34b8eaa54c571b8 Fixes: 8139a4d583ab ("[media] em28xx: move v4l2 user counting fields from struct em28xx to struct v4l2") Cc: stable@vger.kernel.org Signed-off-by: Abhishek Kumar Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman

media: mediatek: vcodec: fix use-after-free in encoder release path

2026-04-22T11:30:51+00:00

commit 76e35091ffc722ba39b303e48bc5d08abb59dd56 upstream. The fops_vcodec_release() function frees the context structure (ctx) without first cancelling any pending or running work in ctx->encode_work. This creates a race window where the workqueue handler (mtk_venc_worker) may still be accessing the context memory after it has been freed. Race condition: CPU 0 (release path) CPU 1 (workqueue) --------------------- ------------------ fops_vcodec_release() v4l2_m2m_ctx_release() v4l2_m2m_cancel_job() // waits for m2m job "done" mtk_venc_worker() v4l2_m2m_job_finish() // m2m job "done" // BUT worker still running! // post-job_finish access: other ctx dereferences // UAF if ctx already freed // returns (job "done") kfree(ctx) // ctx freed Root cause: The v4l2_m2m_ctx_release() only waits for the m2m job lifecycle (via TRANS_RUNNING flag), not the workqueue lifecycle. After v4l2_m2m_job_finish() is called, the m2m framework considers the job complete and v4l2_m2m_ctx_release() returns, but the worker function continues executing and may still access ctx. The work is queued during encode operations via: queue_work(ctx->dev->encode_workqueue, &ctx->encode_work) The worker function accesses ctx->m2m_ctx, ctx->dev, and other ctx fields even after calling v4l2_m2m_job_finish(). This vulnerability was confirmed with KASAN by running an instrumented test module that widens the post-job_finish race window. KASAN detected: BUG: KASAN: slab-use-after-free in mtk_venc_worker+0x159/0x180 Read of size 4 at addr ffff88800326e000 by task kworker/u8:0/12 Workqueue: mtk_vcodec_enc_wq mtk_venc_worker Allocated by task 47: __kasan_kmalloc+0x7f/0x90 fops_vcodec_open+0x85/0x1a0 Freed by task 47: __kasan_slab_free+0x43/0x70 kfree+0xee/0x3a0 fops_vcodec_release+0xb7/0x190 Fix this by calling cancel_work_sync(&ctx->encode_work) before kfree(ctx). This ensures the workqueue handler is both cancelled (if pending) and synchronized (waits for any running handler to complete) before the context is freed. Placement rationale: The fix is placed after v4l2_ctrl_handler_free() and before list_del_init(&ctx->list). At this point, all m2m operations are done (v4l2_m2m_ctx_release() has returned), and we need to ensure the workqueue is synchronized before removing ctx from the list and freeing it. Note: The open error path does NOT need cancel_work_sync() because INIT_WORK() only initializes the work structure - it does not schedule it. Work is only scheduled later during device_run() operations. Fixes: 0934d3759615 ("media: mediatek: vcodec: separate decoder and encoder") Cc: stable@vger.kernel.org Signed-off-by: Fan Wu Reviewed-by: Nicolas Dufresne Signed-off-by: Nicolas Dufresne Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman

media: vidtv: fix nfeeds state corruption on start_streaming failure

2026-04-22T11:30:51+00:00

commit a0e5a598fe9a4612b852406b51153b881592aede upstream. syzbot reported a memory leak in vidtv_psi_service_desc_init [1]. When vidtv_start_streaming() fails inside vidtv_start_feed(), the nfeeds counter is left incremented even though no feed was actually started. This corrupts the driver state: subsequent start_feed calls see nfeeds > 1 and skip starting the mux, while stop_feed calls eventually try to stop a non-existent stream. This state corruption can also lead to memory leaks, since the mux and channel resources may be partially allocated during a failed start_streaming but never cleaned up, as the stop path finds dvb->streaming == false and returns early. Fix by decrementing nfeeds back when start_streaming fails, keeping the counter in sync with the actual number of active feeds. [1] BUG: memory leak unreferenced object 0xffff888145b50820 (size 32): comm "syz.0.17", pid 6068, jiffies 4294944486 backtrace (crc 90a0c7d4): vidtv_psi_service_desc_init+0x74/0x1b0 drivers/media/test-drivers/vidtv/vidtv_psi.c:288 vidtv_channel_s302m_init+0xb1/0x2a0 drivers/media/test-drivers/vidtv/vidtv_channel.c:83 vidtv_channels_init+0x1b/0x40 drivers/media/test-drivers/vidtv/vidtv_channel.c:524 vidtv_mux_init+0x516/0xbe0 drivers/media/test-drivers/vidtv/vidtv_mux.c:518 vidtv_start_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:194 [inline] vidtv_start_feed+0x33e/0x4d0 drivers/media/test-drivers/vidtv/vidtv_bridge.c:239 Fixes: f90cf6079bf67 ("media: vidtv: add a bridge driver") Cc: stable@vger.kernel.org Reported-by: syzbot+639ebc6ec75e96674741@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=639ebc6ec75e96674741 Signed-off-by: Ruslan Valiyev Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman

media: vidtv: fix NULL pointer dereference in vidtv_channel_pmt_match_sections

2026-04-22T11:30:48+00:00

commit f8e1fc918a9fe67103bcda01d20d745f264d00a7 upstream. syzbot reported a general protection fault in vidtv_psi_desc_assign [1]. vidtv_psi_pmt_stream_init() can return NULL on memory allocation failure, but vidtv_channel_pmt_match_sections() does not check for this. When tail is NULL, the subsequent call to vidtv_psi_desc_assign(&tail->descriptor, desc) dereferences a NULL pointer offset, causing a general protection fault. Add a NULL check after vidtv_psi_pmt_stream_init(). On failure, clean up the already-allocated stream chain and return. [1] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:vidtv_psi_desc_assign+0x24/0x90 drivers/media/test-drivers/vidtv/vidtv_psi.c:629 Call Trace: vidtv_channel_pmt_match_sections drivers/media/test-drivers/vidtv/vidtv_channel.c:349 [inline] vidtv_channel_si_init+0x1445/0x1a50 drivers/media/test-drivers/vidtv/vidtv_channel.c:479 vidtv_mux_init+0x526/0xbe0 drivers/media/test-drivers/vidtv/vidtv_mux.c:519 vidtv_start_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:194 [inline] vidtv_start_feed+0x33e/0x4d0 drivers/media/test-drivers/vidtv/vidtv_bridge.c:239 Fixes: f90cf6079bf67 ("media: vidtv: add a bridge driver") Cc: stable@vger.kernel.org Reported-by: syzbot+1f5bcc7c919ec578777a@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=1f5bcc7c919ec578777a Signed-off-by: Ruslan Valiyev Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman

media: rkvdec: reduce stack usage in rkvdec_init_v4l2_vp9_count_tbl()

2026-04-22T11:30:28+00:00

[ Upstream commit c03b7dec3c4ddc97872fa12bfca75bae9cb46510 ] The deeply nested loop in rkvdec_init_v4l2_vp9_count_tbl() needs a lot of registers, so when the clang register allocator runs out, it ends up spilling countless temporaries to the stack: drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c:966:12: error: stack frame size (1472) exceeds limit (1280) in 'rkvdec_vp9_start' [-Werror,-Wframe-larger-than] Marking this function as noinline_for_stack keeps it out of rkvdec_vp9_start(), giving the compiler more room for optimization. The resulting code is good enough that both the total stack usage and the loop get enough better to stay under the warning limit, though it's still slow, and would need a larger rework if this function ends up being called in a fast path. Signed-off-by: Arnd Bergmann Reviewed-by: Nicolas Dufresne Signed-off-by: Nicolas Dufresne Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin

media: verisilicon: Fix kernel panic due to __initconst misuse

2026-04-02T11:25:42+00:00

commit e8d97c270cb46a2a88739019d0f8547adc7d97da upstream. Fix a kernel panic when probing the driver as a module: Unable to handle kernel paging request at virtual address ffffd9c18eb05000 of_find_matching_node_and_match+0x5c/0x1a0 hantro_probe+0x2f4/0x7d0 [hantro_vpu] The imx8mq_vpu_shared_resources array is referenced by variant structures through their shared_devices field. When built as a module, __initconst causes this data to be freed after module init, but it's later accessed during probe, causing a page fault. The imx8mq_vpu_shared_resources is referenced from non-init code, so keeping __initconst or __initconst_or_module here is wrong. Drop the __initconst annotation and let it live in the normal .rodata section. A bug of __initconst called from regular non-init probe code leading to bugs during probe deferrals or during unbind-bind cycles. Reported-by: Krzysztof Kozlowski Closes: https://lore.kernel.org/all/68ef934f-baa0-4bf6-93d8-834bbc441e66@kernel.org/ Reported-by: Franz Schnyder Closes: https://lore.kernel.org/all/n3qmcb62tepxltoskpf7ws6yiirc2so62ia23b42rj3wlmpl67@rvkbuirx7kkp/ Fixes: e0203ddf9af7 ("media: verisilicon: Avoid G2 bus error while decoding H.264 and HEVC") Suggested-by: Krzysztof Kozlowski Suggested-by: Marco Felsch Reviewed-by: Marco Felsch Signed-off-by: Ming Qian Reviewed-by: Frank Li Reviewed-by: Krzysztof Kozlowski Cc: stable@kernel.org Signed-off-by: Nicolas Dufresne Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman

media: mc, v4l2: serialize REINIT and REQBUFS with req_queue_mutex

2026-04-02T11:25:42+00:00

commit bef4f4a88b73e4cc550d25f665b8a9952af22773 upstream. MEDIA_REQUEST_IOC_REINIT can run concurrently with VIDIOC_REQBUFS(0) queue teardown paths. This can race request object cleanup against vb2 queue cancellation and lead to use-after-free reports. We already serialize request queueing against STREAMON/OFF with req_queue_mutex. Extend that serialization to REQBUFS, and also take the same mutex in media_request_ioctl_reinit() so REINIT is in the same exclusion domain. This keeps request cleanup and queue cancellation from running in parallel for request-capable devices. Fixes: 6093d3002eab ("media: vb2: keep a reference to the request until dqbuf") Cc: stable@vger.kernel.org Signed-off-by: Yuchan Nam Signed-off-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman