Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Check the validity of nr_words in bpf_iter_bits_new() Check the validity of nr_words in bpf_iter_bits_new(). Without this check, when multiplication overflow occurs for nr_bits (e.g., when nr_words = 0x0400-0001, nr_bits becomes 64), stack corruption may occur due to bpf_probe_read_kernel_common(..., nr_bytes = 0x2000-0008). Fix it by limiting the maximum value of nr_words to 511. The value is derived from the current implementation of BPF memory allocator. To ensure compatibility if the BPF memory allocator's size limitation changes in the future, use the helper bpf_mem_alloc_check_size() to check whether nr_bytes is too larger. And return -E2BIG instead of -ENOMEM for oversized nr_bytes.

Affected Products 6

References 2

• git.kernel.org https://git.kernel.org/stable/c/393397fbdcad7396639d7077c33f86169184ba99
  Patch
• git.kernel.org https://git.kernel.org/stable/c/c9539e09c67880ecd88b51188c346a2cc078b06c
  Patch

Remediation

• git.kernel.org https://git.kernel.org/stable/c/393397fbdcad7396639d7077c33f86169184ba99
  Patch
• git.kernel.org https://git.kernel.org/stable/c/c9539e09c67880ecd88b51188c346a2cc078b06c
  Patch