CVE-2024-56768: bpf: Fix bpf_get_smp_processor_id() on !CONFIG_SMP
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix bpfgetsmpprocessorid() on !CONFIGSMP
On x86-64 calling bpfgetsmpprocessorid() in a kernel with CONFIGSMP disabled can trigger the following bug, as pcpuhot is unavailable:
[ 8.471774] BUG: unable to handle page fault for address: 00000000936a290c [ 8.471849] #PF: supervisor read access in kernel mode [ 8.471881] #PF: errorcode(0x0000) - not-present page
Fix by inlining a return 0 in the !CONFIGSMP case.
Other sources
This CVE was automatically created from a reference found in an email or other text. If you are reading this, then this CVE entry is probably erroneous, since this text should be replaced by the official CVE description automatically.
— Launchpad
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2024-56768?
CVE-2024-56768 has a high severity due to the potential for bugs to occur when calling bpf_get_smp_processor_id() with CONFIG_SMP disabled.
How do I fix CVE-2024-56768?
To fix CVE-2024-56768, update your Linux kernel to version 6.12.9 or above.
Which versions of the Linux kernel are affected by CVE-2024-56768?
CVE-2024-56768 affects Linux kernel versions 6.10 to 6.12.8 and 6.13-rc1, 6.13-rc2, and 6.13-rc3.
What impact does CVE-2024-56768 have on system performance?
CVE-2024-56768 can lead to system instability and crashes when the bpf_get_smp_processor_id() function is improperly executed.
Is CVE-2024-56768 specific to any hardware architecture?
Yes, CVE-2024-56768 specifically impacts x86-64 architecture when CONFIG_SMP is disabled.