From: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr> mainline inclusion from mainline-v7.3-rc1 commit 783f0f0974c156aca630f4ffff248671082a098d category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/18926 CVE: CVE-2026-89643 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- audit_del_rule() is used for both netlink deletion templates and internal fsnotify autoremove. The former passes a parsed template which owns a temporary tree reference; the latter passes the installed entry itself. The unconditional audit_put_tree() at the end of audit_del_rule() assumes the template case. For mixed AUDIT_DIR plus AUDIT_EXE rules, an fsnotify autoremove event therefore drops the installed rule's live tree reference. Repeating this across rules sharing the same tree can free the tree while another rule still references it, and a later autoremove dereferences the freed pathname while comparing rules. Move the temporary-tree put to audit_rule_change(), the caller that owns deletion templates. Keep it in the AUDIT_DEL_RULE cleanup so both successful deletion and -ENOENT still release the parser-owned tree. Cc: stable@kernel.org Fixes: 34d99af52ad4 ("audit: implement audit by executable") Assisted-by: Codex:gpt-5 Signed-off-by: Jérémy Jean <Jeremy.Jean@oss.cyber.gouv.fr> Reviewed-by: Ricardo Robaina <rrobaina@redhat.com> Tested-by: Ricardo Robaina <rrobaina@redhat.com> [PM: dropped unnecessary comment for line length reasons] Signed-off-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Yi Yang <yiyang13@huawei.com> --- kernel/auditfilter.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index b2cc63ca0068..93b0d459db59 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -1009,7 +1009,6 @@ static inline int audit_add_rule(struct audit_entry *entry) int audit_del_rule(struct audit_entry *entry) { struct audit_entry *e; - struct audit_tree *tree = entry->rule.tree; struct list_head *list; int ret = 0; #ifdef CONFIG_AUDITSYSCALL @@ -1055,9 +1054,6 @@ int audit_del_rule(struct audit_entry *entry) out: mutex_unlock(&audit_filter_mutex); - if (tree) - audit_put_tree(tree); /* that's the temporary one */ - return ret; } @@ -1142,6 +1138,8 @@ int audit_rule_change(int type, int seq, void *data, size_t datasz) } if (err || type == AUDIT_DEL_RULE) { + if (type == AUDIT_DEL_RULE && entry->rule.tree) + audit_put_tree(entry->rule.tree); if (entry->rule.exe) audit_remove_mark(entry->rule.exe); audit_free_rule(entry); -- 2.25.1