Description
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 ]
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
6657fca06e3ffab8d0b3f9d8b397f5ee498952d7 to < 3719d3c36aa853d5a2401af9f8d6b116c91ad5aeaffected6657fca06e3ffab8d0b3f9d8b397f5ee498952d7 to < 3770c38cd6a60494da29ac2da73ff8156440a2d1affected6657fca06e3ffab8d0b3f9d8b397f5ee498952d7 to < 6788b10620ca6e98575d1e06e72a8974aad7657eaffected6657fca06e3ffab8d0b3f9d8b397f5ee498952d7 to < ecba5afe86f30605eb9dfb7f265a8de0218d4cfcaffected6657fca06e3ffab8d0b3f9d8b397f5ee498952d7 to < 5b784489c8158518bf7a466bb3cc045b0fb66b4baffected6657fca06e3ffab8d0b3f9d8b397f5ee498952d7 to < cd287cc208dfe6bd6da98e7f88e723209242c9b4affected6657fca06e3ffab8d0b3f9d8b397f5ee498952d7 to < d35652a5fc9944784f6f50a5c979518ff8dacf61affected
Linux Linux
Default version status: affected
4.17affected0 to < 4.17unaffected4.19.297 to ≤ 4.19.*unaffected5.4.270 to ≤ 5.4.*unaffected5.10.199 to ≤ 5.10.*unaffected5.15.136 to ≤ 5.15.*unaffected6.1.59 to ≤ 6.1.*unaffected6.5.8 to ≤ 6.5.*unaffected6.6 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/3719d3c36aa853d5a2401af9f8d6b116c91ad5ae ↗
- https://git.kernel.org/stable/c/3770c38cd6a60494da29ac2da73ff8156440a2d1 ↗
- https://git.kernel.org/stable/c/6788b10620ca6e98575d1e06e72a8974aad7657e ↗
- https://git.kernel.org/stable/c/ecba5afe86f30605eb9dfb7f265a8de0218d4cfc ↗
- https://git.kernel.org/stable/c/5b784489c8158518bf7a466bb3cc045b0fb66b4b ↗
- https://git.kernel.org/stable/c/cd287cc208dfe6bd6da98e7f88e723209242c9b4 ↗
- https://git.kernel.org/stable/c/d35652a5fc9944784f6f50a5c979518ff8dacf61 ↗