CVE-2025-21676

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> net: fec: handle page_pool_dev_alloc_pages error<br /> <br /> The fec_enet_update_cbd function calls page_pool_dev_alloc_pages but did<br /> not handle the case when it returned NULL. There was a WARN_ON(!new_page)<br /> but it would still proceed to use the NULL pointer and then crash.<br /> <br /> This case does seem somewhat rare but when the system is under memory<br /> pressure it can happen. One case where I can duplicate this with some<br /> frequency is when writing over a smbd share to a SATA HDD attached to an<br /> imx6q.<br /> <br /> Setting /proc/sys/vm/min_free_kbytes to higher values also seems to solve<br /> the problem for my test case. But it still seems wrong that the fec driver<br /> ignores the memory allocation error and can crash.<br /> <br /> This commit handles the allocation error by dropping the current packet.