VMware Photon OS: CVE-2024-53125

VMware Photon OS: CVE-2024-53125

Severity

4

CVSS

(AV:L/AC:M/Au:N/C:P/I:P/A:P)

Published

12/04/2024

Created

01/21/2025

Added

01/20/2025

Modified

01/20/2025

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: sync_linked_regs() must preserve subreg_def Range propagation must not affect subreg_def marks, otherwise the following example is rewritten by verifier incorrectly when BPF_F_TEST_RND_HI32 flag is set: 0: call bpf_ktime_get_ns call bpf_ktime_get_ns 1: r0 &= 0x7fffffff after verifier r0 &= 0x7fffffff 2: w1 = w0rewrites w1 = w0 3: if w0 < 10 goto +0 -------------->r11 = 0x2f5674a6 (r) 4: r1 >>= 32 r11 <<= 32 (r) 5: r0 = r1 r1 |= r11(r) 6: exit; if w0 < 0xa goto pc+0 r1 >>= 32 r0 = r1 exit (or zero extension of w1 at (2) is missing for architectures that require zero extension for upper register half). The following happens w/o this patch: - r0 is marked as not a subreg at (0); - w1 is marked as subreg at (2); - w1 subreg_def is overridden at (3) by copy_register_state(); - w1 is read at (5) but mark_insn_zext() does not mark (2) for zero extension, because w1 subreg_def is not set; - because of BPF_F_TEST_RND_HI32 flag verifier inserts random value for hi32 bits of (2) (marked (r)); - this random value is read at (5).

Solution(s)

• vmware-photon_os_update_tdnf

References

• https://attackerkb.com/topics/cve-2024-53125
• CVE - 2024-53125