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[PATCH v2 2/4] tee: Remove vmalloc page support

Ira Weiny posted 4 patches 2 years, 7 months ago
[PATCH v2 2/4] tee: Remove vmalloc page support
Posted by Ira Weiny 2 years, 7 months ago 
The kernel pages used by shm_get_kernel_pages() are allocated using
GFP_KERNEL through the following call stack:

trusted_instantiate()
	trusted_payload_alloc() -> GFP_KERNEL
	<trusted key op>
		tee_shm_register_kernel_buf()
			register_shm_helper()
				shm_get_kernel_pages()

Where <trusted key op> is one of:

	trusted_key_unseal()
	trusted_key_get_random()
	trusted_key_seal()

Remove the vmalloc page support from shm_get_kernel_pages().  Replace
with a warn on once.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
---
 drivers/tee/tee_shm.c | 36 ++++++++++++------------------------
 1 file changed, 12 insertions(+), 24 deletions(-)

diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
index 27295bda3e0b..527a6eabc03e 100644
--- a/drivers/tee/tee_shm.c
+++ b/drivers/tee/tee_shm.c
@@ -24,37 +24,25 @@ static void shm_put_kernel_pages(struct page **pages, size_t page_count)
 static int shm_get_kernel_pages(unsigned long start, size_t page_count,
 				struct page **pages)
 {
+	struct kvec *kiov;
 	size_t n;
 	int rc;
 
-	if (is_vmalloc_addr((void *)start)) {
-		struct page *page;
-
-		for (n = 0; n < page_count; n++) {
-			page = vmalloc_to_page((void *)(start + PAGE_SIZE * n));
-			if (!page)
-				return -ENOMEM;
-
-			get_page(page);
-			pages[n] = page;
-		}
-		rc = page_count;
-	} else {
-		struct kvec *kiov;
-
-		kiov = kcalloc(page_count, sizeof(*kiov), GFP_KERNEL);
-		if (!kiov)
-			return -ENOMEM;
+	if (WARN_ON_ONCE(is_vmalloc_addr((void *)start)))
+		return -EINVAL;
 
-		for (n = 0; n < page_count; n++) {
-			kiov[n].iov_base = (void *)(start + n * PAGE_SIZE);
-			kiov[n].iov_len = PAGE_SIZE;
-		}
+	kiov = kcalloc(page_count, sizeof(*kiov), GFP_KERNEL);
+	if (!kiov)
+		return -ENOMEM;
 
-		rc = get_kernel_pages(kiov, page_count, 0, pages);
-		kfree(kiov);
+	for (n = 0; n < page_count; n++) {
+		kiov[n].iov_base = (void *)(start + n * PAGE_SIZE);
+		kiov[n].iov_len = PAGE_SIZE;
 	}
 
+	rc = get_kernel_pages(kiov, page_count, 0, pages);
+	kfree(kiov);
+
 	return rc;
 }
 

-- 
2.39.1
Re: [PATCH v2 2/4] tee: Remove vmalloc page support
Posted by Jens Wiklander 2 years, 7 months ago 
On Fri, Feb 03, 2023 at 08:06:33PM -0800, Ira Weiny wrote:
> The kernel pages used by shm_get_kernel_pages() are allocated using
> GFP_KERNEL through the following call stack:
> 
> trusted_instantiate()
> 	trusted_payload_alloc() -> GFP_KERNEL
> 	<trusted key op>
> 		tee_shm_register_kernel_buf()
> 			register_shm_helper()
> 				shm_get_kernel_pages()
> 
> Where <trusted key op> is one of:
> 
> 	trusted_key_unseal()
> 	trusted_key_get_random()
> 	trusted_key_seal()
> 
> Remove the vmalloc page support from shm_get_kernel_pages().  Replace
> with a warn on once.
> 
> Cc: Al Viro <viro@zeniv.linux.org.uk>
> Cc: "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
> Cc: Christoph Hellwig <hch@lst.de>
> Cc: Linus Torvalds <torvalds@linux-foundation.org>
> Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> ---
>  drivers/tee/tee_shm.c | 36 ++++++++++++------------------------
>  1 file changed, 12 insertions(+), 24 deletions(-)

Added to https://git.linaro.org/people/jens.wiklander/linux-tee.git/log/?h=get_kernel_pages-for-v6.4

Thanks,
Jens

> 
> diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
> index 27295bda3e0b..527a6eabc03e 100644
> --- a/drivers/tee/tee_shm.c
> +++ b/drivers/tee/tee_shm.c
> @@ -24,37 +24,25 @@ static void shm_put_kernel_pages(struct page **pages, size_t page_count)
>  static int shm_get_kernel_pages(unsigned long start, size_t page_count,
>  				struct page **pages)
>  {
> +	struct kvec *kiov;
>  	size_t n;
>  	int rc;
>  
> -	if (is_vmalloc_addr((void *)start)) {
> -		struct page *page;
> -
> -		for (n = 0; n < page_count; n++) {
> -			page = vmalloc_to_page((void *)(start + PAGE_SIZE * n));
> -			if (!page)
> -				return -ENOMEM;
> -
> -			get_page(page);
> -			pages[n] = page;
> -		}
> -		rc = page_count;
> -	} else {
> -		struct kvec *kiov;
> -
> -		kiov = kcalloc(page_count, sizeof(*kiov), GFP_KERNEL);
> -		if (!kiov)
> -			return -ENOMEM;
> +	if (WARN_ON_ONCE(is_vmalloc_addr((void *)start)))
> +		return -EINVAL;
>  
> -		for (n = 0; n < page_count; n++) {
> -			kiov[n].iov_base = (void *)(start + n * PAGE_SIZE);
> -			kiov[n].iov_len = PAGE_SIZE;
> -		}
> +	kiov = kcalloc(page_count, sizeof(*kiov), GFP_KERNEL);
> +	if (!kiov)
> +		return -ENOMEM;
>  
> -		rc = get_kernel_pages(kiov, page_count, 0, pages);
> -		kfree(kiov);
> +	for (n = 0; n < page_count; n++) {
> +		kiov[n].iov_base = (void *)(start + n * PAGE_SIZE);
> +		kiov[n].iov_len = PAGE_SIZE;
>  	}
>  
> +	rc = get_kernel_pages(kiov, page_count, 0, pages);
> +	kfree(kiov);
> +
>  	return rc;
>  }
>  
> 
> -- 
> 2.39.1
Re: [PATCH v2 2/4] tee: Remove vmalloc page support
Posted by Sumit Garg 2 years, 7 months ago 
On Sat, 4 Feb 2023 at 09:36, Ira Weiny <ira.weiny@intel.com> wrote:
>
> The kernel pages used by shm_get_kernel_pages() are allocated using
> GFP_KERNEL through the following call stack:
>
> trusted_instantiate()
>         trusted_payload_alloc() -> GFP_KERNEL
>         <trusted key op>
>                 tee_shm_register_kernel_buf()
>                         register_shm_helper()
>                                 shm_get_kernel_pages()
>
> Where <trusted key op> is one of:
>
>         trusted_key_unseal()
>         trusted_key_get_random()
>         trusted_key_seal()
>
> Remove the vmalloc page support from shm_get_kernel_pages().  Replace
> with a warn on once.
>
> Cc: Al Viro <viro@zeniv.linux.org.uk>
> Cc: "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
> Cc: Christoph Hellwig <hch@lst.de>
> Cc: Linus Torvalds <torvalds@linux-foundation.org>
> Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
> Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> ---
>  drivers/tee/tee_shm.c | 36 ++++++++++++------------------------
>  1 file changed, 12 insertions(+), 24 deletions(-)
>

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>

-Sumit

> diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
> index 27295bda3e0b..527a6eabc03e 100644
> --- a/drivers/tee/tee_shm.c
> +++ b/drivers/tee/tee_shm.c
> @@ -24,37 +24,25 @@ static void shm_put_kernel_pages(struct page **pages, size_t page_count)
>  static int shm_get_kernel_pages(unsigned long start, size_t page_count,
>                                 struct page **pages)
>  {
> +       struct kvec *kiov;
>         size_t n;
>         int rc;
>
> -       if (is_vmalloc_addr((void *)start)) {
> -               struct page *page;
> -
> -               for (n = 0; n < page_count; n++) {
> -                       page = vmalloc_to_page((void *)(start + PAGE_SIZE * n));
> -                       if (!page)
> -                               return -ENOMEM;
> -
> -                       get_page(page);
> -                       pages[n] = page;
> -               }
> -               rc = page_count;
> -       } else {
> -               struct kvec *kiov;
> -
> -               kiov = kcalloc(page_count, sizeof(*kiov), GFP_KERNEL);
> -               if (!kiov)
> -                       return -ENOMEM;
> +       if (WARN_ON_ONCE(is_vmalloc_addr((void *)start)))
> +               return -EINVAL;
>
> -               for (n = 0; n < page_count; n++) {
> -                       kiov[n].iov_base = (void *)(start + n * PAGE_SIZE);
> -                       kiov[n].iov_len = PAGE_SIZE;
> -               }
> +       kiov = kcalloc(page_count, sizeof(*kiov), GFP_KERNEL);
> +       if (!kiov)
> +               return -ENOMEM;
>
> -               rc = get_kernel_pages(kiov, page_count, 0, pages);
> -               kfree(kiov);
> +       for (n = 0; n < page_count; n++) {
> +               kiov[n].iov_base = (void *)(start + n * PAGE_SIZE);
> +               kiov[n].iov_len = PAGE_SIZE;
>         }
>
> +       rc = get_kernel_pages(kiov, page_count, 0, pages);
> +       kfree(kiov);
> +
>         return rc;
>  }
>
>
> --
> 2.39.1
Re: [PATCH v2 2/4] tee: Remove vmalloc page support
Posted by Christoph Hellwig 2 years, 7 months ago 
Looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>

Patchew 2.1-devel-b67e4c2

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