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From: Lukas Wunner <lukas@wunner.de>
To: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>,
	manivannan.sadhasivam@oss.qualcomm.com,
	linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] PCI: Fix NULL pointer access in pci_store_saved_state()
Date: Wed, 8 Apr 2026 12:59:59 +0200	[thread overview]
Message-ID: <adY1L6R88SLtpZzN@wunner.de> (raw)
In-Reply-To: <89dda312-92ff-4957-bf67-dd0b60f681b8@oss.qualcomm.com>

On Wed, Apr 08, 2026 at 03:16:28PM +0530, Krishna Chaitanya Chundru wrote:
> On 4/5/2026 1:32 PM, Lukas Wunner wrote:
> > On Sat, Apr 04, 2026 at 02:23:00PM +0530, Krishna Chaitanya Chundru wrote:
> > No, please validate values read from config space with
> > PCI_POSSIBLE_ERROR() before using them to access memory at
> > a location that may be out-of-bounds.  Or cache the size on
> > enumeration and avoid re-reading it upon pci_save_state().
> 
> pci_save_state() has many config reading having check for each read
> is not ideal way

The ask is not to guard every config space read with a check,
but only ones which are used to calculate the offset into a
memory allocation.  We only need to prevent out-of-bounds
memory accesses.  We do not need to prevent saving "all ones".

Thanks,

Lukas

      reply	other threads:[~2026-04-08 11:00 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-04-04  8:52 [PATCH 0/2] PCI: Fix NULL pointer access in pci_store_saved_state() Krishna Chaitanya Chundru
2026-04-04  8:52 ` [PATCH 1/2] PCI: Add pcie_link_is_active() to determine if the link is active Krishna Chaitanya Chundru
2026-04-04  8:53 ` [PATCH 2/2] PCI: Fix NULL pointer access in pci_store_saved_state() Krishna Chaitanya Chundru
2026-04-05  8:02   ` Lukas Wunner
2026-04-08  9:46     ` Krishna Chaitanya Chundru
2026-04-08 10:59       ` Lukas Wunner [this message]

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