Re: [PATCH v2 1/2] audit: fix removal of dangling executable rules
From: Paul Moore
Date: Tue May 26 2026 - 19:00:26 EST
On May 13, 2026 Ricardo Robaina <rrobaina@xxxxxxxxxx> wrote:
>
> When an audited executable is deleted from the disk, its dentry
> becomes negative. Any later attempt to delete the associated audit
> rule will lead to audit_alloc_mark() encountering this negative
> dentry and immediately aborting, returning -ENOENT.
>
> This early abort prevents the subsystem from allocating the temporary
> fsnotify mark needed to construct the search key, meaning the kernel
> cannot find the existing rule in its own lists to delete it. This
> leaves a dangling rule in memory, resulting in the following error
> while attempting to delete the rule:
>
> # ./audit-dupe-exe-deadlock.sh
> No rules
> Error deleting rule (No such file or directory)
> There was an error while processing parameters
>
> # auditctl -l
> -a always,exit -S all -F exe=/tmp/file -F path=/tmp/file -F key=dr
>
> # auditctl -D
> Error deleting rule (No such file or directory)
> There was an error while processing parameters
>
> This patch fixes this issue by removing the d_really_is_negative()
> check. By doing so, a dummy mark can be successfully generated for
> the deleted path, which allows the audit subsystem to properly match
> and flush the dangling rule.
>
> Fixes: 76a53de6f7ff ("VFS/audit: introduce kern_path_parent() for audit")
> Acked-by: Waiman Long <longman@xxxxxxxxxx>
> Acked-by: Richard Guy Briggs <rgb@xxxxxxxxxx>
> Signed-off-by: Ricardo Robaina <rrobaina@xxxxxxxxxx>
> ---
> Changes in v2:
> - New patch order: now patch 1/2 (was 2/2 in v1) per maintainer feedback
>
> kernel/audit_fsnotify.c | 4 ----
> 1 file changed, 4 deletions(-)
Annotated for stable, but merged into audit/dev as I want to give this a
few extra weeks of soak time in linux-next.
--
paul-moore.com