Re: CVE-2026-89603: entry: Fix seccomp bypass after ptrace with TSYNC

[Greg Kroah-Hartman]

On Thu, Oct 15, 2026 at 06:34:13PM +0200, Oleg Nesterov wrote:
> On 10/15, Kees Cook wrote:
> >
> > On Fri, Sep 11, 2026 at 09:44:52PM +0200, Greg Kroah-Hartman wrote:
> > > This race condition could allow an unprivileged process to execute
> > > a prohibited system call (e.g., execve) that the newly installed filter
> > > was intended to block, especially since the tracer might have modified
> > > the system call number during the ptrace stop.
> >
> > I'm disputing this one: please reject CVE-2026-89603. The fix is a fine
> > consistency change, but the flaw gave neither the tracer nor the tracee
> > anything they didn't already have.
> 
> Thanks Kees!
> 
> I fully agree with both points. The patch is fine, but it doesn't fix
> any security problem.

Now rejected, thanks for the review and letting us know!

greg k-h