CVE-2026-53076

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> bpf: Fix OOB in pcpu_init_value<br /> <br /> An out-of-bounds read occurs when copying element from a<br /> BPF_MAP_TYPE_CGROUP_STORAGE map to another pcpu map with the<br /> same value_size that is not rounded up to 8 bytes.<br /> <br /> The issue happens when:<br /> 1. A CGROUP_STORAGE map is created with value_size not aligned to<br /> 8 bytes (e.g., 4 bytes)<br /> 2. A pcpu map is created with the same value_size (e.g., 4 bytes)<br /> 3. Update element in 2 with data in 1<br /> <br /> pcpu_init_value assumes that all sources are rounded up to 8 bytes,<br /> and invokes copy_map_value_long to make a data copy, However, the<br /> assumption doesn&amp;#39;t stand since there are some cases where the source<br /> may not be rounded up to 8 bytes, e.g., CGROUP_STORAGE, skb-&gt;data.<br /> the verifier verifies exactly the size that the source claims, not<br /> the size rounded up to 8 bytes by kernel, an OOB happens when the<br /> source has only 4 bytes while the copy size(4) is rounded up to 8.