7.1

CVE-2023-52504

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 ]
Data is provided by the National Vulnerability Database (NVD)
Linux ≫ Linux Kernel Version >= 4.17 < 4.19.297
Linux ≫ Linux Kernel Version >= 4.20 < 5.4.270
Linux ≫ Linux Kernel Version >= 5.5 < 5.10.199
Linux ≫ Linux Kernel Version >= 5.11 < 5.15.136
Linux ≫ Linux Kernel Version >= 5.16 < 6.1.59
Linux ≫ Linux Kernel Version >= 6.2 < 6.5.8
Linux ≫ Linux Kernel Version6.6 Updaterc1
Linux ≫ Linux Kernel Version6.6 Updaterc2
Linux ≫ Linux Kernel Version6.6 Updaterc3
Linux ≫ Linux Kernel Version6.6 Updaterc4
Linux ≫ Linux Kernel Version6.6 Updaterc5
Zu dieser CVE wurde keine CISA KEV oder CERT.AT-Warnung gefunden.
EPSS Metriken
Type Source Score Percentile
EPSS FIRST.org 0.01% 0.005
CVSS Metriken
Source Base Score Exploit Score Impact Score Vector string
nvd@nist.gov 7.1 1.8 5.2
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
CWE-125 Out-of-bounds Read

The product reads data past the end, or before the beginning, of the intended buffer.