[PATCH RESEND] PCI/AER: Check for NULL aer_info before ratelimiting in pci_print_aer()

[Breno Leitao]

On Wed, Oct 01, 2025 at 04:36:57PM -0500, Bjorn Helgaas wrote:
> On Mon, Sep 29, 2025 at 02:15:47AM -0700, Breno Leitao wrote:
> > Similarly to pci_dev_aer_stats_incr(), pci_print_aer() may be called
> > when dev->aer_info is NULL. Add a NULL check before proceeding to avoid
> > calling aer_ratelimit() with a NULL aer_info pointer, returning 1, which
> > does not rate limit, given this is fatal.
> > 
> > This prevents a kernel crash triggered by dereferencing a NULL pointer
> > in aer_ratelimit(), ensuring safer handling of PCI devices that lack
> > AER info. This change aligns pci_print_aer() with pci_dev_aer_stats_incr()
> > which already performs this NULL check.
> > 
> > Cc: stable at vger.kernel.org
> > Fixes: a57f2bfb4a5863 ("PCI/AER: Ratelimit correctable and non-fatal error logging")
> > Signed-off-by: Breno Leitao <leitao at debian.org>
> 
> Thanks, Breno, I applied this to pci/aer for v6.18.  I added a little
> more detail to the commit log because the path where we hit this is a
> bit obscure.  Please take a look and see if it makes sense:

Thanks! That’s exactly what I would have written if I actually knew what
I was doing. :-)