Tracker / CVE-2026-43203
CVE-2026-43203
In the Linux kernel, the following vulnerability has been resolved: atm: fore200e: fix use-after-free in tasklets during device removal When the PCA-200E or SBA-200E adapter is being detached, the fore200e is deallocated. However, the tx_tasklet or rx_tasklet may still be running or pending, leading to use-after-free bug when the already freed fore200e is accessed again in fore200e_tx_tasklet() or fore200e_rx_tasklet(). One of the race conditions can occur as follows: CPU 0 (cleanup) | CPU 1 (tasklet) fore200e_pca_remove_one() | fore200e_interrupt() fore200e_shutdown() | tasklet_schedule() kfree(fore200e) | fore200e_tx_tasklet() | fore200e-> // UAF Fix this by ensuring tx_tasklet or rx_tasklet is properly canceled before the fore200e is released. Add tasklet_kill() in fore200e_shutdown() to synchronize with any pending or running tasklets. Moreover, since fore200e_reset() could prevent further interrupts or data transfers, the tasklet_kill() should be placed after fore200e_reset() to prevent the tasklet from being rescheduled in fore200e_interrupt(). Finally, it only needs to do tasklet_kill() when the fore200e state is greater than or equal to FORE200E_STATE_IRQ, since tasklets are uninitialized in earlier states. In a word, the tasklet_kill() should be placed in the FORE200E_STATE_IRQ branch within the switch...case structure. This bug was identified through static analysis.
Affected products and versions
| linux | linux_kernel |
|---|---|
| linux | linux_kernel · 2.6.12.1 → 5.10.252 |
| linux | linux_kernel · 5.11 → 5.15.202 |
| linux | linux_kernel · 5.16 → 6.1.165 |
| linux | linux_kernel · 6.13 → 6.18.16 |
| linux | linux_kernel · 6.19 → 6.19.6 |
| linux | linux_kernel · 6.2 → 6.6.128 |
| linux | linux_kernel · 6.7 → 6.12.75 |