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 ]
Vendor | Product | Version | CPE |
---|---|---|---|
linux | linux_kernel | * | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
[
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"arch/x86/kernel/alternative.c"
],
"versions": [
{
"version": "6657fca06e3f",
"lessThan": "3719d3c36aa8",
"status": "affected",
"versionType": "git"
},
{
"version": "6657fca06e3f",
"lessThan": "3770c38cd6a6",
"status": "affected",
"versionType": "git"
},
{
"version": "6657fca06e3f",
"lessThan": "6788b10620ca",
"status": "affected",
"versionType": "git"
},
{
"version": "6657fca06e3f",
"lessThan": "ecba5afe86f3",
"status": "affected",
"versionType": "git"
},
{
"version": "6657fca06e3f",
"lessThan": "5b784489c815",
"status": "affected",
"versionType": "git"
},
{
"version": "6657fca06e3f",
"lessThan": "cd287cc208df",
"status": "affected",
"versionType": "git"
},
{
"version": "6657fca06e3f",
"lessThan": "d35652a5fc99",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"arch/x86/kernel/alternative.c"
],
"versions": [
{
"version": "4.17",
"status": "affected"
},
{
"version": "0",
"lessThan": "4.17",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "4.19.297",
"lessThanOrEqual": "4.19.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.4.270",
"lessThanOrEqual": "5.4.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.10.199",
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.15.136",
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.1.59",
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.5.8",
"lessThanOrEqual": "6.5.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.6",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
]
git.kernel.org/stable/c/3719d3c36aa853d5a2401af9f8d6b116c91ad5ae
git.kernel.org/stable/c/3770c38cd6a60494da29ac2da73ff8156440a2d1
git.kernel.org/stable/c/5b784489c8158518bf7a466bb3cc045b0fb66b4b
git.kernel.org/stable/c/6788b10620ca6e98575d1e06e72a8974aad7657e
git.kernel.org/stable/c/cd287cc208dfe6bd6da98e7f88e723209242c9b4
git.kernel.org/stable/c/d35652a5fc9944784f6f50a5c979518ff8dacf61
git.kernel.org/stable/c/ecba5afe86f30605eb9dfb7f265a8de0218d4cfc