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CVE-2024-58100: bpf: check changes_pkt_data property for extension programs

Description

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

bpf: check changes_pkt_data property for extension programs

When processing calls to global sub-programs, verifier decides whether
to invalidate all packet pointers in current state depending on the
changes_pkt_data property of the global sub-program.

Because of this, an extension program replacing a global sub-program
must be compatible with changes_pkt_data property of the sub-program
being replaced.

This commit:
- adds changes_pkt_data flag to struct bpf_prog_aux:
- this flag is set in check_cfg() for main sub-program;
- in jit_subprogs() for other sub-programs;
- modifies bpf_check_attach_btf_id() to check changes_pkt_data flag;
- moves call to check_attach_btf_id() after the call to check_cfg(),
because it needs changes_pkt_data flag to be set:

bpf_check:
... ...
- check_attach_btf_id resolve_pseudo_ldimm64
resolve_pseudo_ldimm64 --> bpf_prog_is_offloaded
bpf_prog_is_offloaded check_cfg
check_cfg + check_attach_btf_id
... ...

The following fields are set by check_attach_btf_id():
- env->ops
- prog->aux->attach_btf_trace
- prog->aux->attach_func_name
- prog->aux->attach_func_proto
- prog->aux->dst_trampoline
- prog->aux->mod
- prog->aux->saved_dst_attach_type
- prog->aux->saved_dst_prog_type
- prog->expected_attach_type

Neither of these fields are use...

Classification

CVE ID: CVE-2024-58100

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.02% (probability of being exploited)

EPSS Percentile: 4.36% (scored less or equal to compared to others)

EPSS Date: 2025-06-03 (when was this score calculated)

References

https://nvd.nist.gov/vuln/detail/CVE-2024-58100
https://git.kernel.org/stable/c/3846e2bea565ee1c5195dcc625fda9868fb0e3b3
https://git.kernel.org/stable/c/81f6d0530ba031b5f038a091619bf2ff29568852

Timeline