In the Linux kernel, the following vulnerability has been resolved:
x86/alternatives: Disable KASAN in apply_alternatives()
Fei has reported that KASAN triggers during apply_alternatives() on
a 5-level paging machine:
BUG: KASAN: out-of-bounds in rcu_is_watching()
Read of size 4 at addr ff110003ee6419a0 by task swapper/0/0
...
__asan_load4()
rcu_is_watching()
trace_hardirqs_on()
text_poke_early()
apply_alternatives()
...
On machines with 5-level paging, cpu_feature_enabled(X86_FEATURE_LA57)
gets patched. It includes KASAN code, where KASAN_SHADOW_START depends on
__VIRTUAL_MASK_SHIFT, which is defined with cpu_feature_enabled().
KASAN gets confused when apply_alternatives() patches the
KASAN_SHADOW_START users. A test patch that makes KASAN_SHADOW_START
static, by replacing __VIRTUAL_MASK_SHIFT with 56, works around the issue.
Fix it for real by disabling KASAN while the kernel is patching alternatives.
[ mingo: updated the changelog ]
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References
History
No history.
MITRE
Status: PUBLISHED
Assigner: Linux
Published: 2024-03-02T21:52:18.500Z
Updated: 2024-11-04T14:48:09.122Z
Reserved: 2024-02-20T12:30:33.314Z
Link: CVE-2023-52504
Vulnrichment
Updated: 2024-08-02T23:03:20.409Z
NVD
Status : Awaiting Analysis
Published: 2024-03-02T22:15:47.300
Modified: 2024-03-04T13:58:23.447
Link: CVE-2023-52504
Redhat