In the Linux kernel, the following vulnerability has been...
Moderate severity
Unreviewed
Published
Aug 22, 2024
to the GitHub Advisory Database
•
Updated Aug 23, 2024
Description
Published by the National Vulnerability Database
Aug 22, 2024
Published to the GitHub Advisory Database
Aug 22, 2024
Last updated
Aug 23, 2024
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix crash due to out of bounds access into reg2btf_ids.
When commit e6ac2450d6de ("bpf: Support bpf program calling kernel function") added
kfunc support, it defined reg2btf_ids as a cheap way to translate the verifier
reg type to the appropriate btf_vmlinux BTF ID, however
commit c25b2ae13603 ("bpf: Replace PTR_TO_XXX_OR_NULL with PTR_TO_XXX | PTR_MAYBE_NULL")
moved the __BPF_REG_TYPE_MAX from the last member of bpf_reg_type enum to after
the base register types, and defined other variants using type flag
composition. However, now, the direct usage of reg->type to index into
reg2btf_ids may no longer fall into __BPF_REG_TYPE_MAX range, and hence lead to
out of bounds access and kernel crash on dereference of bad pointer.
References