CVE-2025-21980: linux kernel vulnerability

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().
CVE-2025-21980CVSS 5.5Linux

CVE-2025-21980: linux kernel vulnerability

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().

CVSS
5.5 MEDIUM
EPSS
7.47%
Known exploited
not in KEV
Product
linux kernel

What is known

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().

Sources

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