[OE-core][PATCH v4 5/8] cve-exclusions: set status for CVE-2022-4543

[Junjie Cao <junjie.cao@linux.dev>]

KPTI clones the kernel entry text into the user page tables at its
KASLR-slid address and, on CPUs with PGE, sets the global bit on those
entries. The translation survives the CR3 write on kernel exit, and a
local attacker can time prefetch instructions across the kernel range
to recover the KASLR base in under a second.

Disclosure and write-up:

  https://www.openwall.com/lists/oss-security/2022/12/16/3
  https://www.willsroot.io/2022/12/entrybleed.html

The disclosure states that after discussion with security@kernel.org
and linux-distros "a fix for this is currently not available", and none
has appeared since; arch/x86/mm/pti.c still clones the entry text and
sets _PAGE_GLOBAL on the cloned mapping. Debian notes "Ignored
upstream and KASLR is not expected to be resistant to local attacks";
Ubuntu has the fix deferred since 2023-01-10:

  https://security-tracker.debian.org/tracker/CVE-2022-4543
  https://ubuntu.com/security/CVE-2022-4543

CC: Paul Barker <paul@pbarker.dev>
AI-Generated: Uses Claude (claude-opus-5)
Signed-off-by: Junjie Cao <junjie.cao@linux.dev>
---
v4:
- use the review's comment and status wording; drop the cpu_entry_area
  commit reference
- tighten the mechanism wording and the timing claim to match the
  cited sources

v3: https://lore.kernel.org/openembedded-core/20260812072842.1176341-1-junjie.cao@linux.dev/

 meta/recipes-kernel/linux/cve-exclusion.inc | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/meta/recipes-kernel/linux/cve-exclusion.inc b/meta/recipes-kernel/linux/cve-exclusion.inc
index a9b4d9a2..4318fc79 100644
--- a/meta/recipes-kernel/linux/cve-exclusion.inc
+++ b/meta/recipes-kernel/linux/cve-exclusion.inc
@@ -222,3 +222,12 @@ CVE_STATUS[CVE-2021-3864] = "unpatched: Proposed fixes were not merged upstream"
 # Fix https://git.kernel.org/linus/d860d1faa6b2ce3becfdb8b0c2b048ad31800061
 # Fix https://git.kernel.org/linus/da9c9c877597170b929a6121a68dcd3dd9a80f45
 CVE_STATUS[CVE-2022-1247] = "fixed-version: Fixed from version 6.17"
+
+# Triaged August 2026 - "EntryBleed", discussed with the kernel security team
+# but no fix appears to have been published since then. Debian says "Ignored
+# upstream and KASLR is not expected to be resistant to local attacks", fix
+# deferred in Ubuntu.
+# https://www.openwall.com/lists/oss-security/2022/12/16/3
+# https://security-tracker.debian.org/tracker/CVE-2022-4543
+# https://ubuntu.com/security/CVE-2022-4543
+CVE_STATUS[CVE-2022-4543] = "unpatched: No fix has been proposed"
-- 
2.43.0