In the Linux kernel, the following vulnerability has been resolved:

bpf: Fix NULL deref in map_kptr_match_type for scalar regs

Commit ab6c637ad027 ("bpf: Fix a bpf_kptr_xchg() issue with local
kptr") refactored map_kptr_match_type() to branch on btf_is_kernel()
before checking base_type(). A scalar register stored into a kptr
slot has no btf, so the btf_is_kernel(reg->btf) call dereferences
NULL.

Move the base_type() != PTR_TO_BTF_ID guard before any reg->btf
access.

https://git.kernel.org/stable/c/0a36c1f72888bca0237295a4da19cd91821a90be

https://git.kernel.org/stable/c/4d0a375887ab4d49e4da1ff10f9606cab8f7c3ad

https://git.kernel.org/stable/c/520454e839710c327808c2fcc98e28cee77355fc

https://git.kernel.org/stable/c/6982653ce5f119982aa58f1af58e7bfbebf39252

https://git.kernel.org/stable/c/da1d615ce49a47986a8864e2371a26e97861085c

[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","programFiles":["kernel/bpf/verifier.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","versions":[{"version":"ab6c637ad0276e42f8acabcbc64932a6d346dab3","lessThan":"520454e839710c327808c2fcc98e28cee77355fc","versionType":"git","status":"affected"},{"version":"ab6c637ad0276e42f8acabcbc64932a6d346dab3","lessThan":"0a36c1f72888bca0237295a4da19cd91821a90be","versionType":"git","status":"affected"},{"version":"ab6c637ad0276e42f8acabcbc64932a6d346dab3","lessThan":"6982653ce5f119982aa58f1af58e7bfbebf39252","versionType":"git","status":"affected"},{"version":"ab6c637ad0276e42f8acabcbc64932a6d346dab3","lessThan":"da1d615ce49a47986a8864e2371a26e97861085c","versionType":"git","status":"affected"},{"version":"ab6c637ad0276e42f8acabcbc64932a6d346dab3","lessThan":"4d0a375887ab4d49e4da1ff10f9606cab8f7c3ad","versionType":"git","status":"affected"},{"version":"af3d2e0f3a54e67806959d161e613457772babc5","versionType":"git","status":"affected"},{"version":"4782968e0d631b0d8944dcfd4bf8fb49be087101","versionType":"git","status":"affected"},{"version":"6.4.16","lessThan":"6.5","versionType":"semver","status":"affected"},{"version":"6.5.3","lessThan":"6.6","versionType":"semver","status":"affected"}]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","programFiles":["kernel/bpf/verifier.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","versions":[{"version":"6.6","status":"affected"},{"version":"0","lessThan":"6.6","versionType":"semver","status":"unaffected"},{"version":"6.6.141","lessThanOrEqual":"6.6.*","versionType":"semver","status":"unaffected"},{"version":"6.12.91","lessThanOrEqual":"6.12.*","versionType":"semver","status":"unaffected"},{"version":"6.18.33","lessThanOrEqual":"6.18.*","versionType":"semver","status":"unaffected"},{"version":"7.0.10","lessThanOrEqual":"7.0.*","versionType":"semver","status":"unaffected"},{"version":"7.1","lessThanOrEqual":"*","versionType":"original_commit_for_fix","status":"unaffected"}]}]