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.

• linux linux kernel (>= 4.12 < 5.4.297) • linux linux kernel (>= 5.5 < 5.10.241) • linux linux kernel (>= 5.11 < 5.15.190) • linux linux kernel (>= 5.16 < 6.1.149) • linux linux kernel (>= 6.2 < 6.6.103) • linux linux kernel (>= 6.7 < 6.12.44) • linux linux kernel (>= 6.13 < 6.16.4) • debian debian linux 11.0