CVE Vulnerabilities

CVE-2024-58098

Published: May 05, 2025 | Modified: May 05, 2025
CVSS 3.x
N/A
Source:
NVD
CVSS 2.x
RedHat/V2
RedHat/V3
5.5 MODERATE
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Ubuntu
MEDIUM

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

bpf: track changes_pkt_data property for global functions

When processing calls to certain helpers, verifier invalidates all packet pointers in a current state. For example, consider the following program:

__attribute__((__noinline__))
long skb_pull_data(struct __sk_buff *sk, __u32 len)
{
    return bpf_skb_pull_data(sk, len);
}

SEC(tc)
int test_invalidate_checks(struct __sk_buff *sk)
{
    int *p = (void *)(long)sk->data;
    if ((void *)(p + 1) > (void *)(long)sk->data_end) return TCX_DROP;
    skb_pull_data(sk, 0);
    *p = 42;
    return TCX_PASS;
}

After a call to bpf_skb_pull_data() the pointer p cant be used safely. See function filter.c:bpf_helper_changes_pkt_data() for a list of such helpers.

At the moment verifier invalidates packet pointers when processing helper function calls, and does not traverse global sub-programs when processing calls to global sub-programs. This means that calls to helpers done from global sub-programs do not invalidate pointers in the caller state. E.g. the program above is unsafe, but is not rejected by verifier.

This commit fixes the omission by computing field bpf_subprog_info->changes_pkt_data for each sub-program before main verification pass. changes_pkt_data should be set if:

  • subprogram calls helper for which bpf_helper_changes_pkt_data returns true;
  • subprogram calls a global function, for which bpf_subprog_info->changes_pkt_data should be set.

The verifier.c:check_cfg() pass is modified to compute this information. The commit relies on depth first instruction traversal done by check_cfg() and absence of recursive function calls:

  • check_cfg() would eventually visit every call to subprogram S in a state when S is fully explored;
  • when S is fully explored:
    • every direct helper call within S is explored (and thus changes_pkt_data is set if needed);
    • every call to subprogram S1 called by S was visited with S1 fully explored (and thus S inherits changes_pkt_data from S1).

The downside of such approach is that dead code elimination is not taken into account: if a helper call inside global function is dead because of current configuration, verifier would conservatively assume that the call occurs for the purpose of the changes_pkt_data computation.

Affected Software

Name Vendor Start Version End Version
Linux-allwinner-5.19 Ubuntu jammy *
Linux-allwinner-5.19 Ubuntu upstream *
Linux-aws-5.0 Ubuntu esm-infra/bionic *
Linux-aws-5.0 Ubuntu upstream *
Linux-aws-5.11 Ubuntu focal *
Linux-aws-5.11 Ubuntu upstream *
Linux-aws-5.13 Ubuntu focal *
Linux-aws-5.13 Ubuntu upstream *
Linux-aws-5.19 Ubuntu jammy *
Linux-aws-5.19 Ubuntu upstream *
Linux-aws-5.3 Ubuntu esm-infra/bionic *
Linux-aws-5.3 Ubuntu upstream *
Linux-aws-5.8 Ubuntu focal *
Linux-aws-5.8 Ubuntu upstream *
Linux-aws-6.2 Ubuntu jammy *
Linux-aws-6.2 Ubuntu upstream *
Linux-aws-6.5 Ubuntu jammy *
Linux-aws-6.5 Ubuntu upstream *
Linux-azure Ubuntu esm-infra/bionic *
Linux-azure-5.11 Ubuntu focal *
Linux-azure-5.11 Ubuntu upstream *
Linux-azure-5.13 Ubuntu focal *
Linux-azure-5.13 Ubuntu upstream *
Linux-azure-5.19 Ubuntu jammy *
Linux-azure-5.19 Ubuntu upstream *
Linux-azure-5.3 Ubuntu esm-infra/bionic *
Linux-azure-5.3 Ubuntu upstream *
Linux-azure-5.8 Ubuntu focal *
Linux-azure-5.8 Ubuntu upstream *
Linux-azure-6.2 Ubuntu jammy *
Linux-azure-6.2 Ubuntu upstream *
Linux-azure-6.5 Ubuntu jammy *
Linux-azure-6.5 Ubuntu upstream *
Linux-azure-edge Ubuntu esm-infra/bionic *
Linux-azure-edge Ubuntu upstream *
Linux-azure-fde Ubuntu focal *
Linux-azure-fde-5.19 Ubuntu jammy *
Linux-azure-fde-5.19 Ubuntu upstream *
Linux-azure-fde-6.2 Ubuntu jammy *
Linux-azure-fde-6.2 Ubuntu upstream *
Linux-gcp Ubuntu esm-infra/bionic *
Linux-gcp-5.11 Ubuntu focal *
Linux-gcp-5.11 Ubuntu upstream *
Linux-gcp-5.13 Ubuntu focal *
Linux-gcp-5.13 Ubuntu upstream *
Linux-gcp-5.19 Ubuntu jammy *
Linux-gcp-5.19 Ubuntu upstream *
Linux-gcp-5.3 Ubuntu esm-infra/bionic *
Linux-gcp-5.3 Ubuntu upstream *
Linux-gcp-5.8 Ubuntu focal *
Linux-gcp-5.8 Ubuntu upstream *
Linux-gcp-6.2 Ubuntu jammy *
Linux-gcp-6.2 Ubuntu upstream *
Linux-gcp-6.5 Ubuntu jammy *
Linux-gcp-6.5 Ubuntu upstream *
Linux-gke Ubuntu focal *
Linux-gke-4.15 Ubuntu esm-infra/bionic *
Linux-gke-4.15 Ubuntu upstream *
Linux-gke-5.15 Ubuntu focal *
Linux-gke-5.15 Ubuntu upstream *
Linux-gke-5.4 Ubuntu esm-infra/bionic *
Linux-gke-5.4 Ubuntu upstream *
Linux-gkeop Ubuntu focal *
Linux-gkeop-5.15 Ubuntu focal *
Linux-gkeop-5.4 Ubuntu esm-infra/bionic *
Linux-gkeop-5.4 Ubuntu upstream *
Linux-hwe Ubuntu esm-infra/bionic *
Linux-hwe-5.11 Ubuntu focal *
Linux-hwe-5.11 Ubuntu upstream *
Linux-hwe-5.13 Ubuntu focal *
Linux-hwe-5.13 Ubuntu upstream *
Linux-hwe-5.19 Ubuntu jammy *
Linux-hwe-5.19 Ubuntu upstream *
Linux-hwe-5.8 Ubuntu focal *
Linux-hwe-5.8 Ubuntu upstream *
Linux-hwe-6.2 Ubuntu jammy *
Linux-hwe-6.2 Ubuntu upstream *
Linux-hwe-6.5 Ubuntu jammy *
Linux-hwe-6.5 Ubuntu upstream *
Linux-hwe-edge Ubuntu esm-infra/bionic *
Linux-hwe-edge Ubuntu esm-infra/xenial *
Linux-hwe-edge Ubuntu upstream *
Linux-intel-5.13 Ubuntu focal *
Linux-intel-5.13 Ubuntu upstream *
Linux-lowlatency-hwe-5.19 Ubuntu jammy *
Linux-lowlatency-hwe-5.19 Ubuntu upstream *
Linux-lowlatency-hwe-6.2 Ubuntu jammy *
Linux-lowlatency-hwe-6.2 Ubuntu upstream *
Linux-lowlatency-hwe-6.5 Ubuntu jammy *
Linux-lowlatency-hwe-6.5 Ubuntu upstream *
Linux-nvidia-6.2 Ubuntu jammy *
Linux-nvidia-6.2 Ubuntu upstream *
Linux-nvidia-6.5 Ubuntu jammy *
Linux-nvidia-6.5 Ubuntu upstream *
Linux-oem Ubuntu esm-infra/bionic *
Linux-oem Ubuntu upstream *
Linux-oem-5.10 Ubuntu focal *
Linux-oem-5.10 Ubuntu upstream *
Linux-oem-5.13 Ubuntu focal *
Linux-oem-5.13 Ubuntu upstream *
Linux-oem-5.14 Ubuntu focal *
Linux-oem-5.14 Ubuntu upstream *
Linux-oem-5.17 Ubuntu jammy *
Linux-oem-5.17 Ubuntu upstream *
Linux-oem-5.6 Ubuntu focal *
Linux-oem-5.6 Ubuntu upstream *
Linux-oem-6.0 Ubuntu jammy *
Linux-oem-6.0 Ubuntu upstream *
Linux-oem-6.1 Ubuntu jammy *
Linux-oem-6.1 Ubuntu upstream *
Linux-oem-6.5 Ubuntu jammy *
Linux-oem-6.5 Ubuntu upstream *
Linux-oracle-5.0 Ubuntu esm-infra/bionic *
Linux-oracle-5.0 Ubuntu upstream *
Linux-oracle-5.11 Ubuntu focal *
Linux-oracle-5.11 Ubuntu upstream *
Linux-oracle-5.13 Ubuntu focal *
Linux-oracle-5.13 Ubuntu upstream *
Linux-oracle-5.3 Ubuntu esm-infra/bionic *
Linux-oracle-5.3 Ubuntu upstream *
Linux-oracle-5.8 Ubuntu focal *
Linux-oracle-5.8 Ubuntu upstream *
Linux-oracle-6.5 Ubuntu jammy *
Linux-oracle-6.5 Ubuntu upstream *
Linux-raspi2 Ubuntu focal *
Linux-raspi2 Ubuntu upstream *
Linux-realtime Ubuntu jammy *
Linux-realtime Ubuntu noble *
Linux-riscv Ubuntu focal *
Linux-riscv Ubuntu jammy *
Linux-riscv-5.11 Ubuntu focal *
Linux-riscv-5.11 Ubuntu upstream *
Linux-riscv-5.19 Ubuntu jammy *
Linux-riscv-5.19 Ubuntu upstream *
Linux-riscv-5.8 Ubuntu focal *
Linux-riscv-5.8 Ubuntu upstream *
Linux-riscv-6.5 Ubuntu jammy *
Linux-riscv-6.5 Ubuntu upstream *
Linux-starfive-5.19 Ubuntu jammy *
Linux-starfive-5.19 Ubuntu upstream *
Linux-starfive-6.2 Ubuntu jammy *
Linux-starfive-6.2 Ubuntu upstream *
Linux-starfive-6.5 Ubuntu jammy *
Linux-starfive-6.5 Ubuntu upstream *

References