Tracker / CVE-2025-39713
CVE-2025-39713
In the Linux kernel, the following vulnerability has been resolved: media: rainshadow-cec: fix TOCTOU race condition in rain_interrupt() 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.
Affected products and versions
| debian | debian_linux |
|---|---|
| linux | linux_kernel · 4.12 → 5.4.297 |
| linux | linux_kernel · 5.11 → 5.15.190 |
| linux | linux_kernel · 5.16 → 6.1.149 |
| linux | linux_kernel · 5.5 → 5.10.241 |
| linux | linux_kernel · 6.13 → 6.16.4 |
| linux | linux_kernel · 6.2 → 6.6.103 |
| linux | linux_kernel · 6.7 → 6.12.44 |