CVE Published: 22/08/2024 |
CVE Updated: 04/11/2024 |
CVE Year: 2022 Source: Linux |
Vendor: Linux |
Product: Linux Status : PUBLISHED
CVE-2022-48929 Description
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.