[patch] drivers/iommu/amd_iommu.c: argument page_size could be uninitialized

[patch] drivers/iommu/amd_iommu.c: argument page_size could be uninitialized

[Yizhuo Zhai]

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Argument "page_size" passing to function "fetch_pte" could be uninitialized
if the function returns NULL. The caller "iommu_unmap_page" checks the
return value but the page_size is used outside the if block.

Signed-off-by: yzhai003-3vSkeFsW7jA@public.gmane.org <yzhai003-3vSkeFsW7jA@public.gmane.org>
---
 drivers/iommu/amd_iommu.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 774e057..3a23e97 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1397,6 +1397,7 @@ static u64 *fetch_pte(struct protection_domain
*domain,
 {
  int level;
  u64 *pte;
+ *page_size = 0;

  if (address > PM_LEVEL_SIZE(domain->mode))
  return NULL;
-- 
2.7.4
-- 
Kind Regards,

*Yizhuo Zhai*

*Computer Science, Graduate Student*
*University of California, Riverside *

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Re: [patch] drivers/iommu/amd_iommu.c: argument page_size could be uninitialized

[Joerg Roedel]

Hi Yizhuo Zhai,

your mail is a mime/multipart email with a html version. Please send a
plain text email with the patch in it. You can use git-send-email for
that. This patch doesn't apply through my git workflow.

Also, please change the subject to:

	
	[PATCH] iommu/amd: Argument page_size could be uninitialized

This matches upstream conventions for iommu patches. So make these
changes and re-post this patch after the next merge-window.

On Thu, May 31, 2018 at 11:20:28AM -0700, Yizhuo Zhai wrote:
> Argument "page_size" passing to function "fetch_pte" could be uninitialized if
> the function returns NULL. The caller "iommu_unmap_page" checks the return
> value but the page_size is used outside the if block.
> 
> Signed-off-by: yzhai003@ucr.edu <yzhai003@ucr.edu>
> ---
>  drivers/iommu/amd_iommu.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
> index 774e057..3a23e97 100644
> --- a/drivers/iommu/amd_iommu.c
> +++ b/drivers/iommu/amd_iommu.c
> @@ -1397,6 +1397,7 @@ static u64 *fetch_pte(struct protection_domain *domain,
>  {
>   int level;
>   u64 *pte;
> + *page_size = 0;

Please put a newline between variable definitions and code.


Thanks,

	Joerg