CVE-2025-21980 Information

Description

In the Linux kernel the following vulnerability has been resolved:

sched: address a potential NULL pointer dereference in the GRED scheduler.

If kzalloc in gred_init returns a NULL pointer the code follows the error handling path invoking gred_destroy. This in turn calls gred_offload where memset could receive a NULL pointer as input potentially leading to a kernel crash.

When table->opt is NULL in gred_init() gred_change_table_def() is not called yet so it is not necessary to call ->ndo_setup_tc() in gred_offload().

Reference

https://git.kernel.org/stable/c/0f0a152957d64ce45b4c27c687e7d087e8f45079 https://git.kernel.org/stable/c/115ef44a98220fddfab37a39a19370497cd718b9 https://git.kernel.org/stable/c/5f996b4f80c2cef1f9c77275055e7fcba44c9199 https://git.kernel.org/stable/c/68896dd50180b38ea552e49a6a00b685321e5769 https://git.kernel.org/stable/c/d02c9acd68950a444acda18d514e2b41f846cb7f