txEnd() in fs/jfs/jfs_txnmgr.c reads the log pointer from the superblock
info, drops TXN_LOCK and then takes log->gclock, while lmLogClose() can
free that log during umount.

The subsystem in the public CVE data is misleading: the "slub"
association comes from the KASAN slab report, but the affected code is
JFS. Red Hat's own title for the issue is "slab-use-after-free write in
txend due to race condition".

A fix adding a new mutex was posted, reviewed, and then withdrawn by its
author, who wrote "I think my fix method is not a good solution":

  https://lore.kernel.org/all/[email protected]/

No other fix has been posted, and the sequence in txEnd() is unchanged
in mainline as of linux-next 20260727. syzkaller was still reporting
"KASAN: slab-use-after-free Write in txEnd" in June 2026.

Ubuntu records "unfixed upstream as of 2023-09-01"; Debian lists
src:linux as vulnerable in every suite:

  https://ubuntu.com/security/CVE-2023-3397
  https://security-tracker.debian.org/tracker/CVE-2023-3397

CONFIG_JFS_FS=n in both ktypes/standard/standard.cfg and
ktypes/preempt-rt/preempt-rt.cfg in yocto-kernel-cache, and no fragment
there enables it; the only other occurrence is CONFIG_JFS_SECURITY in
the selinux feature, which has no effect without JFS_FS.

CC: Paul Barker <[email protected]>
AI-Generated: Uses Claude (claude-opus-5)
Signed-off-by: Junjie Cao <[email protected]>
---
changes in v2:
- split out of the single combined patch, one CVE per patch as requested
- added primary source links (disclosures, distribution trackers, mailing
  list threads, upstream commits) to every commit message
- added the three CVEs with no upstream fix as "unpatched" entries instead
  of leaving them undocumented
- disclosed AI assistance per the contributor guide

v1: 
https://lore.kernel.org/openembedded-core/[email protected]/

 meta/recipes-kernel/linux/cve-exclusion.inc | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/meta/recipes-kernel/linux/cve-exclusion.inc 
b/meta/recipes-kernel/linux/cve-exclusion.inc
index 3517318e..827a487e 100644
--- a/meta/recipes-kernel/linux/cve-exclusion.inc
+++ b/meta/recipes-kernel/linux/cve-exclusion.inc
@@ -232,3 +232,10 @@ CVE_STATUS[CVE-2022-1247] = "fixed-version: Fixed from 
version 6.17"
 # https://www.willsroot.io/2022/12/entrybleed.html
 CVE_STATUS[CVE-2022-4543] = "upstream-wontfix: no fix planned, KASLR is not \
 considered a defence against local attackers"
+
+# JFS txEnd()/lmLogClose() use-after-free, not slub as the CVE data says.
+# The only proposed fix was withdrawn by its author; the racy code is
+# unchanged and syzbot still reproduces it as of June 2026.
+# https://lore.kernel.org/all/[email protected]/
+CVE_STATUS[CVE-2023-3397] = "unpatched: no upstream fix, the only proposed \
+patch was withdrawn by its author and the affected fs/jfs code is unchanged"
-- 
2.43.0

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