iommu.lists.linux-foundation.org archive mirror
 help / color / mirror / Atom feed
From: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
To: gregkh@linuxfoundation.org
Cc: iommu@lists.linux-foundation.org, stable@vger.kernel.org
Subject: [PATCH v2] iommu: amd: Fix IO_PAGE_FAULT due to __unmap_single() size overflow
Date: Wed, 24 Jun 2020 08:41:21 +0000	[thread overview]
Message-ID: <20200624084121.6588-1-suravee.suthikulpanit@amd.com> (raw)

Currently, an integer is used to specify the size in unmap_sg().
With 2GB worth of pages (512k 4k pages), it requires 31 bits
(i.e. (1 << 19) << 12), which overflows the integer, and ends up
unmapping more pages than intended. Subsequently, this results in
IO_PAGE_FAULT.

Uses size_t instead of int to pass parameter to __unmap_single().

Please note that this patch is only for the stable-kernels tree
because the commit be62dbf554c5 ("iommu/amd: Convert AMD iommu driver
to the dma-iommu api"), which removes the function unmap_sg()
was introduced in v5.5. This patch is not applicable in subsequent
kernel versions.

Cc: stable@vger.kernel.org
Cc: iommu@lists.linux-foundation.org
Reported-by: Robert Lippert <rlippert@google.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
---

 drivers/iommu/amd_iommu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 32de8e7bb8b4..7adc021932b8 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -2670,7 +2670,7 @@ static void unmap_sg(struct device *dev, struct scatterlist *sglist,
 	struct protection_domain *domain;
 	struct dma_ops_domain *dma_dom;
 	unsigned long startaddr;
-	int npages;
+	size_t npages;
 
 	domain = get_domain(dev);
 	if (IS_ERR(domain))
-- 
2.17.1

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

             reply	other threads:[~2020-06-24 10:13 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-24  8:41 Suravee Suthikulpanit [this message]
2020-06-24  9:09 ` [PATCH v2] iommu: amd: Fix IO_PAGE_FAULT due to __unmap_single() size overflow Greg KH
2020-06-24 11:58   ` Joerg Roedel
2020-07-30  7:28     ` Greg KH
2020-06-24 11:55 ` Joerg Roedel

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=20200624084121.6588-1-suravee.suthikulpanit@amd.com \
    --to=suravee.suthikulpanit@amd.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=iommu@lists.linux-foundation.org \
    --cc=stable@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).