CVE-2024-45020 (GCVE-0-2024-45020)
Vulnerability from cvelistv5
Published
2024-09-11 15:13
Modified
2026-08-05 11:37
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix a kernel verifier crash in stacksafe() Daniel Hodges reported a kernel verifier crash when playing with sched-ext. Further investigation shows that the crash is due to invalid memory access in stacksafe(). More specifically, it is the following code: if (exact != NOT_EXACT && old->stack[spi].slot_type[i % BPF_REG_SIZE] != cur->stack[spi].slot_type[i % BPF_REG_SIZE]) return false; The 'i' iterates old->allocated_stack. If cur->allocated_stack < old->allocated_stack the out-of-bound access will happen. To fix the issue add 'i >= cur->allocated_stack' check such that if the condition is true, stacksafe() should fail. Otherwise, cur->stack[spi].slot_type[i % BPF_REG_SIZE] memory access is legal.
References
Impacted products
Vendor Product Version
Linux Linux Version: ab470fefce2837e66b771c60858118d50bb5bb10
Version: 2793a8b015f7f1caadb9bce9c63dc659f7522676
Version: 2793a8b015f7f1caadb9bce9c63dc659f7522676
Version: 6.6.15   ≤
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