kvm.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Zhenyu Wang <zhenyuw@linux.intel.com>
To: kvm@vger.kernel.org
Cc: Colin Xu <colin.xu@gmail.com>, Dmitry Torokhov <dtor@chromium.org>
Subject: [PATCH] vfio/pci: Fix OpRegion read
Date: Fri, 19 Nov 2021 16:14:35 +0800	[thread overview]
Message-ID: <20211119081435.3237699-1-zhenyuw@linux.intel.com> (raw)

This is to fix incorrect pointer arithmetic which caused wrong
OpRegion version returned, then VM driver got error to get wanted
VBT block. We need to be safe to return correct data, so force
pointer type for byte access.

Fixes: 49ba1a2976c8 ("vfio/pci: Add OpRegion 2.0+ Extended VBT support.")
Cc: Colin Xu <colin.xu@gmail.com>
Cc: Dmitry Torokhov <dtor@chromium.org>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
---
 drivers/vfio/pci/vfio_pci_igd.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/vfio/pci/vfio_pci_igd.c b/drivers/vfio/pci/vfio_pci_igd.c
index 56cd551e0e04..dad6eeed5e80 100644
--- a/drivers/vfio/pci/vfio_pci_igd.c
+++ b/drivers/vfio/pci/vfio_pci_igd.c
@@ -98,7 +98,7 @@ static ssize_t vfio_pci_igd_rw(struct vfio_pci_core_device *vdev,
 			version = cpu_to_le16(0x0201);
 
 		if (igd_opregion_shift_copy(buf, &off,
-					    &version + (pos - OPREGION_VERSION),
+					    (u8 *)&version + (pos - OPREGION_VERSION),
 					    &pos, &remaining, bytes))
 			return -EFAULT;
 	}
@@ -121,7 +121,7 @@ static ssize_t vfio_pci_igd_rw(struct vfio_pci_core_device *vdev,
 					  OPREGION_SIZE : 0);
 
 		if (igd_opregion_shift_copy(buf, &off,
-					    &rvda + (pos - OPREGION_RVDA),
+					    (u8 *)&rvda + (pos - OPREGION_RVDA),
 					    &pos, &remaining, bytes))
 			return -EFAULT;
 	}
-- 
2.33.1


             reply	other threads:[~2021-11-19  8:14 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-19  8:14 Zhenyu Wang [this message]
2021-11-21 14:01 ` [PATCH] vfio/pci: Fix OpRegion read Colin Xu
2021-11-24  0:56 ` Colin Xu
2021-11-25  5:13   ` Zhenyu Wang
2021-11-30 19:30     ` Alex Williamson

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211119081435.3237699-1-zhenyuw@linux.intel.com \
    --to=zhenyuw@linux.intel.com \
    --cc=colin.xu@gmail.com \
    --cc=dtor@chromium.org \
    --cc=kvm@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).