kernel/linux.git/drivers/media/cec, branch v5.15.208

media: cec: Fix debugfs leak on bus_register() failure

2026-01-19T12:10:02+00:00

commit c43bcd2b2aa3c2ca9d2433c3990ecbc2c47d10eb upstream. In cec_devnode_init(), the debugfs directory created with debugfs_create_dir() is not removed if bus_register() fails. This leaves a stale "cec" entry in debugfs and prevents proper module reloading. Fix this by removing the debugfs directory in the error path. Fixes: a56960e8b406 ("[media] cec: add HDMI CEC framework (core)") Cc: stable@vger.kernel.org Signed-off-by: Haotian Zhang Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman

media: rainshadow-cec: fix TOCTOU race condition in rain_interrupt()

2025-08-28T14:24:29+00:00

commit 7af160aea26c7dc9e6734d19306128cce156ec40 upstream. In the interrupt handler rain_interrupt(), the buffer full check on rain->buf_len is performed before acquiring rain->buf_lock. This creates a Time-of-Check to Time-of-Use (TOCTOU) race condition, as rain->buf_len is concurrently accessed and modified in the work handler rain_irq_work_handler() under the same lock. Multiple interrupt invocations can race, with each reading buf_len before it becomes full and then proceeding. This can lead to both interrupts attempting to write to the buffer, incrementing buf_len beyond its capacity (DATA_SIZE) and causing a buffer overflow. Fix this bug by moving the spin_lock() to before the buffer full check. This ensures that the check and the subsequent buffer modification are performed atomically, preventing the race condition. An corresponding spin_unlock() is added to the overflow path to correctly release the lock. This possible bug was found by an experimental static analysis tool developed by our team. Fixes: 0f314f6c2e77 ("[media] rainshadow-cec: new RainShadow Tech HDMI CEC driver") Cc: stable@vger.kernel.org Signed-off-by: Gui-Dong Han Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman

media: pulse8-cec: fix data timestamp at pulse8_setup()

2024-11-14T12:13:38+00:00

commit ba9cf6b430433e57bfc8072364e944b7c0eca2a4 upstream. As pointed by Coverity, there is a hidden overflow condition there. As date is signed and u8 is unsigned, doing: date = (data[0] << 24) With a value bigger than 07f will make all upper bits of date 0xffffffff. This can be demonstrated with this small code:


typedef int64_t time64_t;
typedef uint8_t u8;

int main(void)
{
	u8 data[] = { 0xde ,0xad , 0xbe, 0xef };
	time64_t date;

	date = (data[0] << 24) | (data[1] << 16) | (data[2] << 8) | data[3];
	printf("Invalid data = 0x%08lx\n", date);

	date = ((unsigned)data[0] << 24) | (data[1] << 16) | (data[2] << 8) | data[3];
	printf("Expected data = 0x%08lx\n", date);

	return 0;
}

Fix it by converting the upper bit calculation to unsigned. Fixes: cea28e7a55e7 ("media: pulse8-cec: reorganize function order") Cc: stable@vger.kernel.org Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman

media: cec: core: add adap_nb_transmit_canceled() callback

2024-06-16T11:39:53+00:00

commit da53c36ddd3f118a525a04faa8c47ca471e6c467 upstream. A potential deadlock was found by Zheng Zhang with a local syzkaller instance. The problem is that when a non-blocking CEC transmit is canceled by calling cec_data_cancel, that in turn can call the high-level received() driver callback, which can call cec_transmit_msg() to transmit a new message. The cec_data_cancel() function is called with the adap->lock mutex held, and cec_transmit_msg() tries to take that same lock. The root cause is that the received() callback can either be used to pass on a received message (and then adap->lock is not held), or to report a canceled transmit (and then adap->lock is held). This is confusing, so create a new low-level adap_nb_transmit_canceled callback that reports back that a non-blocking transmit was canceled. And the received() callback is only called when a message is received, as was the case before commit f9d0ecbf56f4 ("media: cec: correctly pass on reply results") complicated matters. Reported-by: Zheng Zhang Signed-off-by: Hans Verkuil Fixes: f9d0ecbf56f4 ("media: cec: correctly pass on reply results") Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman

media: cec: core: avoid confusing "transmit timed out" message

2024-06-16T11:39:45+00:00

[ Upstream commit cbe499977bc36fedae89f0a0d7deb4ccde9798fe ] If, when waiting for a transmit to finish, the wait is interrupted, then you might get a "transmit timed out" message, even though the transmit was interrupted and did not actually time out. Set transmit_in_progress_aborted to true if the wait_for_completion_killable() call was interrupted and ensure that the transmit is properly marked as ABORTED. Signed-off-by: Hans Verkuil Reported-by: Yang, Chenyuan Closes: https://lore.kernel.org/linux-media/PH7PR11MB57688E64ADE4FE82E658D86DA09EA@PH7PR11MB5768.namprd11.prod.outlook.com/ Fixes: 590a8e564c6e ("media: cec: abort if the current transmit was canceled") Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin

media: cec: core: avoid recursive cec_claim_log_addrs

2024-06-16T11:39:45+00:00

[ Upstream commit 47c82aac10a6954d68f29f10d9758d016e8e5af1 ] Keep track if cec_claim_log_addrs() is running, and return -EBUSY if it is when calling CEC_ADAP_S_LOG_ADDRS. This prevents a case where cec_claim_log_addrs() could be called while it was still in progress. Signed-off-by: Hans Verkuil Reported-by: Yang, Chenyuan Closes: https://lore.kernel.org/linux-media/PH7PR11MB57688E64ADE4FE82E658D86DA09EA@PH7PR11MB5768.namprd11.prod.outlook.com/ Fixes: ca684386e6e2 ("[media] cec: add HDMI CEC framework (api)") Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin

media: cec-adap.c: drop activate_cnt, use state info instead

2024-06-16T11:39:45+00:00

[ Upstream commit f9222f8ca18bcb1d55dd749b493b29fd8092fb82 ] Using an activation counter to decide when the enable or disable the cec adapter is not the best approach and can lead to race conditions. Change this to determining the current status of the adapter, and enable or disable the adapter accordingly. It now only needs to be called whenever there is a chance that the state changes, and it can handle enabling/disabling monitoring as well if needed. This simplifies the code and it should be a more robust approach as well. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Stable-dep-of: 47c82aac10a6 ("media: cec: core: avoid recursive cec_claim_log_addrs") Signed-off-by: Sasha Levin

media: cec: use call_op and check for !unregistered

2024-06-16T11:39:45+00:00

[ Upstream commit e2ed5024ac2bc27d4bfc99fd58f5ab54de8fa965 ] Use call_(void_)op consistently in the CEC core framework. Ditto for the cec pin ops. And check if !adap->devnode.unregistered before calling each op. This avoids calls to ops when the device has been unregistered and the underlying hardware may be gone. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Stable-dep-of: 47c82aac10a6 ("media: cec: core: avoid recursive cec_claim_log_addrs") Signed-off-by: Sasha Levin

media: cec: correctly pass on reply results

2024-06-16T11:39:45+00:00

[ Upstream commit f9d0ecbf56f4b90745a6adc5b59281ad8f70ab54 ] The results of non-blocking transmits were not correctly communicated to userspace. Specifically: 1) if a non-blocking transmit was canceled, then rx_status wasn't set to 0 as it should. 2) if the non-blocking transmit succeeded, but the corresponding reply never arrived (aborted or timed out), then tx_status wasn't set to 0 as it should, and rx_status was hardcoded to ABORTED instead of the actual reason, such as TIMEOUT. In addition, adap->ops->received() was never called, so drivers that want to do message processing themselves would not be informed of the failed reply. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Stable-dep-of: 47c82aac10a6 ("media: cec: core: avoid recursive cec_claim_log_addrs") Signed-off-by: Sasha Levin

media: cec: abort if the current transmit was canceled

2024-06-16T11:39:44+00:00

[ Upstream commit 590a8e564c6eff7e77a84e728612f1269e3c0685 ] If a transmit-in-progress was canceled, then, once the transmit is done, mark it as aborted and refrain from retrying the transmit. To signal this situation the new transmit_in_progress_aborted field is set to true. The old implementation would just set adap->transmitting to NULL and set adap->transmit_in_progress to false, but on the hardware level the transmit was still ongoing. However, the framework would think the transmit was aborted, and if a new transmit was issued, then it could overwrite the HW buffer containing the old transmit with the new transmit, leading to garbled data on the CEC bus. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Stable-dep-of: 47c82aac10a6 ("media: cec: core: avoid recursive cec_claim_log_addrs") Signed-off-by: Sasha Levin