diff mbox series

[-next,v5,4/5] arm64: mm: add support for page table check

Message ID 20220421082042.1167967-5-tongtiangen@huawei.com (mailing list archive)
State New, archived
Headers show
Series mm: page_table_check: add support on arm64 and riscv | expand

Commit Message

Tong Tiangen April 21, 2022, 8:20 a.m. UTC 
From: Kefeng Wang <wangkefeng.wang@huawei.com>

As commit d283d422c6c4 ("x86: mm: add x86_64 support for page table
check"), add some necessary page table check hooks into routines that
modify user page tables.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Tong Tiangen <tongtiangen@huawei.com>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
---
 arch/arm64/Kconfig               |  1 +
 arch/arm64/include/asm/pgtable.h | 65 +++++++++++++++++++++++++++++---
 2 files changed, 61 insertions(+), 5 deletions(-)

Comments

Anshuman Khandual April 22, 2022, 6:45 a.m. UTC | #1 
Please change the subject line as

arm64/mm: Enable ARCH_SUPPORTS_PAGE_TABLE_CHECK

OR

arm64/mm: Subscribe ARCH_SUPPORTS_PAGE_TABLE_CHECK

On 4/21/22 13:50, Tong Tiangen wrote:
> From: Kefeng Wang <wangkefeng.wang@huawei.com>
> 
> As commit d283d422c6c4 ("x86: mm: add x86_64 support for page table
> check"), add some necessary page table check hooks into routines that
> modify user page tables.

Please make the commit message comprehensive, which should include

- Enabling ARCH_SUPPORTS_PAGE_TABLE_CHECK on arm64
- Adding all additional page table helpers required for PAGE_TABLE_CHECK
- Instrumenting existing page table helpers with page table check hooks

> 
> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
> Signed-off-by: Tong Tiangen <tongtiangen@huawei.com>
> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
> ---
>  arch/arm64/Kconfig               |  1 +
>  arch/arm64/include/asm/pgtable.h | 65 +++++++++++++++++++++++++++++---
>  2 files changed, 61 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 18a18a0e855d..c1509525ab8e 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -92,6 +92,7 @@ config ARM64
>  	select ARCH_SUPPORTS_ATOMIC_RMW
>  	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
>  	select ARCH_SUPPORTS_NUMA_BALANCING
> +	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
>  	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
>  	select ARCH_WANT_DEFAULT_BPF_JIT
>  	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
> index 930077f7b572..9f8f97a7cc7c 100644
> --- a/arch/arm64/include/asm/pgtable.h
> +++ b/arch/arm64/include/asm/pgtable.h
> @@ -33,6 +33,7 @@
>  #include <linux/mmdebug.h>
>  #include <linux/mm_types.h>
>  #include <linux/sched.h>
> +#include <linux/page_table_check.h>
>  
>  #ifdef CONFIG_TRANSPARENT_HUGEPAGE
>  #define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
> @@ -96,6 +97,7 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys)
>  #define pte_young(pte)		(!!(pte_val(pte) & PTE_AF))
>  #define pte_special(pte)	(!!(pte_val(pte) & PTE_SPECIAL))
>  #define pte_write(pte)		(!!(pte_val(pte) & PTE_WRITE))
> +#define pte_user(pte)		(!!(pte_val(pte) & PTE_USER))
>  #define pte_user_exec(pte)	(!(pte_val(pte) & PTE_UXN))
>  #define pte_cont(pte)		(!!(pte_val(pte) & PTE_CONT))
>  #define pte_devmap(pte)		(!!(pte_val(pte) & PTE_DEVMAP))
> @@ -312,7 +314,7 @@ static inline void __check_racy_pte_update(struct mm_struct *mm, pte_t *ptep,
>  		     __func__, pte_val(old_pte), pte_val(pte));
>  }
>  
> -static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
> +static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
>  			      pte_t *ptep, pte_t pte)
>  {
>  	if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
> @@ -343,6 +345,13 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
>  	set_pte(ptep, pte);
>  }
>  
> +static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
> +			      pte_t *ptep, pte_t pte)
> +{
> +	page_table_check_pte_set(mm, addr, ptep, pte);
> +	return __set_pte_at(mm, addr, ptep, pte);
> +}
> +
>  /*
>   * Huge pte definitions.
>   */
> @@ -454,6 +463,8 @@ static inline int pmd_trans_huge(pmd_t pmd)
>  #define pmd_dirty(pmd)		pte_dirty(pmd_pte(pmd))
>  #define pmd_young(pmd)		pte_young(pmd_pte(pmd))
>  #define pmd_valid(pmd)		pte_valid(pmd_pte(pmd))
> +#define pmd_user(pmd)		pte_user(pmd_pte(pmd))
> +#define pmd_user_exec(pmd)	pte_user_exec(pmd_pte(pmd))
>  #define pmd_cont(pmd)		pte_cont(pmd_pte(pmd))
>  #define pmd_wrprotect(pmd)	pte_pmd(pte_wrprotect(pmd_pte(pmd)))
>  #define pmd_mkold(pmd)		pte_pmd(pte_mkold(pmd_pte(pmd)))
> @@ -501,8 +512,19 @@ static inline pmd_t pmd_mkdevmap(pmd_t pmd)
>  #define pud_pfn(pud)		((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
>  #define pfn_pud(pfn,prot)	__pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
>  
> -#define set_pmd_at(mm, addr, pmdp, pmd)	set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd))
> -#define set_pud_at(mm, addr, pudp, pud)	set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud))
> +static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
> +			      pmd_t *pmdp, pmd_t pmd)
> +{
> +	page_table_check_pmd_set(mm, addr, pmdp, pmd);
> +	return __set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd));
> +}
> +
> +static inline void set_pud_at(struct mm_struct *mm, unsigned long addr,
> +			      pud_t *pudp, pud_t pud)
> +{
> +	page_table_check_pud_set(mm, addr, pudp, pud);
> +	return __set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud));
> +}
>  
>  #define __p4d_to_phys(p4d)	__pte_to_phys(p4d_pte(p4d))
>  #define __phys_to_p4d_val(phys)	__phys_to_pte_val(phys)
> @@ -643,6 +665,24 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd)
>  #define pud_present(pud)	pte_present(pud_pte(pud))
>  #define pud_leaf(pud)		pud_sect(pud)
>  #define pud_valid(pud)		pte_valid(pud_pte(pud))
> +#define pud_user(pud)		pte_user(pud_pte(pud))
> +
> +#ifdef CONFIG_PAGE_TABLE_CHECK
> +static inline bool pte_user_accessible_page(pte_t pte)
> +{
> +	return pte_present(pte) && (pte_user(pte) || pte_user_exec(pte));
> +}
> +
> +static inline bool pmd_user_accessible_page(pmd_t pmd)
> +{
> +	return pmd_present(pmd) && (pmd_user(pmd) || pmd_user_exec(pmd));
> +}
> +
> +static inline bool pud_user_accessible_page(pud_t pud)
> +{
> +	return pud_present(pud) && pud_user(pud);
> +}
> +#endif
>  
>  static inline void set_pud(pud_t *pudp, pud_t pud)
>  {
> @@ -872,11 +912,21 @@ static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
>  }
>  #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
>  
> +static inline pte_t __ptep_get_and_clear(struct mm_struct *mm,
> +				       unsigned long address, pte_t *ptep)
> +{
> +	return __pte(xchg_relaxed(&pte_val(*ptep), 0));
> +}
> +
>  #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
>  static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
>  				       unsigned long address, pte_t *ptep)
>  {
> -	return __pte(xchg_relaxed(&pte_val(*ptep), 0));
> +	pte_t pte = __ptep_get_and_clear(mm, address, ptep);
>

__ptep_get_and_clear() is not required. Please keep the __pte(xchg_relaxed(..),..)
unchanged as in the case with pmdp_huge_get_and_clear() helper below.

 +
> +	page_table_check_pte_clear(mm, address, pte);
> +
> +	return pte;
>  }
>  
>  #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> @@ -884,7 +934,11 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
>  static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
>  					    unsigned long address, pmd_t *pmdp)
>  {
> -	return pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp));
> +	pmd_t pmd = pte_pmd(__ptep_get_and_clear(mm, address, (pte_t *)pmdp));
> +
> +	page_table_check_pmd_clear(mm, address, pmd);
> +
> +	return pmd;
>  }
>  #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
>  
> @@ -918,6 +972,7 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm,
>  static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
>  		unsigned long address, pmd_t *pmdp, pmd_t pmd)
>  {
> +	page_table_check_pmd_set(vma->vm_mm, address, pmdp, pmd);
>  	return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
>  }
>  #endif
Tong Tiangen April 24, 2022, 4:14 a.m. UTC | #2 
在 2022/4/22 14:45, Anshuman Khandual 写道:
> Please change the subject line as
> 
> arm64/mm: Enable ARCH_SUPPORTS_PAGE_TABLE_CHECK
> 
> OR
> 
> arm64/mm: Subscribe ARCH_SUPPORTS_PAGE_TABLE_CHECK
> 
> On 4/21/22 13:50, Tong Tiangen wrote:
>> From: Kefeng Wang <wangkefeng.wang@huawei.com>
>>
>> As commit d283d422c6c4 ("x86: mm: add x86_64 support for page table
>> check"), add some necessary page table check hooks into routines that
>> modify user page tables.
> 
> Please make the commit message comprehensive, which should include
> 
> - Enabling ARCH_SUPPORTS_PAGE_TABLE_CHECK on arm64
> - Adding all additional page table helpers required for PAGE_TABLE_CHECK
> - Instrumenting existing page table helpers with page table check hooks
> 

Good suggestion, if i need to do a new version for some other reason i 
think it should be described more comprehensively.

Thanks,
Tong.

>>
>> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
>> Signed-off-by: Tong Tiangen <tongtiangen@huawei.com>
>> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
>> ---
>>   arch/arm64/Kconfig               |  1 +
>>   arch/arm64/include/asm/pgtable.h | 65 +++++++++++++++++++++++++++++---
>>   2 files changed, 61 insertions(+), 5 deletions(-)
>>
>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
>> index 18a18a0e855d..c1509525ab8e 100644
>> --- a/arch/arm64/Kconfig
>> +++ b/arch/arm64/Kconfig
>> @@ -92,6 +92,7 @@ config ARM64
>>   	select ARCH_SUPPORTS_ATOMIC_RMW
>>   	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
>>   	select ARCH_SUPPORTS_NUMA_BALANCING
>> +	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
>>   	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
>>   	select ARCH_WANT_DEFAULT_BPF_JIT
>>   	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
>> diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
>> index 930077f7b572..9f8f97a7cc7c 100644
>> --- a/arch/arm64/include/asm/pgtable.h
>> +++ b/arch/arm64/include/asm/pgtable.h
>> @@ -33,6 +33,7 @@
>>   #include <linux/mmdebug.h>
>>   #include <linux/mm_types.h>
>>   #include <linux/sched.h>
>> +#include <linux/page_table_check.h>
>>   
>>   #ifdef CONFIG_TRANSPARENT_HUGEPAGE
>>   #define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
>> @@ -96,6 +97,7 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys)
>>   #define pte_young(pte)		(!!(pte_val(pte) & PTE_AF))
>>   #define pte_special(pte)	(!!(pte_val(pte) & PTE_SPECIAL))
>>   #define pte_write(pte)		(!!(pte_val(pte) & PTE_WRITE))
>> +#define pte_user(pte)		(!!(pte_val(pte) & PTE_USER))
>>   #define pte_user_exec(pte)	(!(pte_val(pte) & PTE_UXN))
>>   #define pte_cont(pte)		(!!(pte_val(pte) & PTE_CONT))
>>   #define pte_devmap(pte)		(!!(pte_val(pte) & PTE_DEVMAP))
>> @@ -312,7 +314,7 @@ static inline void __check_racy_pte_update(struct mm_struct *mm, pte_t *ptep,
>>   		     __func__, pte_val(old_pte), pte_val(pte));
>>   }
>>   
>> -static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
>> +static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
>>   			      pte_t *ptep, pte_t pte)
>>   {
>>   	if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
>> @@ -343,6 +345,13 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
>>   	set_pte(ptep, pte);
>>   }
>>   
>> +static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
>> +			      pte_t *ptep, pte_t pte)
>> +{
>> +	page_table_check_pte_set(mm, addr, ptep, pte);
>> +	return __set_pte_at(mm, addr, ptep, pte);
>> +}
>> +
>>   /*
>>    * Huge pte definitions.
>>    */
>> @@ -454,6 +463,8 @@ static inline int pmd_trans_huge(pmd_t pmd)
>>   #define pmd_dirty(pmd)		pte_dirty(pmd_pte(pmd))
>>   #define pmd_young(pmd)		pte_young(pmd_pte(pmd))
>>   #define pmd_valid(pmd)		pte_valid(pmd_pte(pmd))
>> +#define pmd_user(pmd)		pte_user(pmd_pte(pmd))
>> +#define pmd_user_exec(pmd)	pte_user_exec(pmd_pte(pmd))
>>   #define pmd_cont(pmd)		pte_cont(pmd_pte(pmd))
>>   #define pmd_wrprotect(pmd)	pte_pmd(pte_wrprotect(pmd_pte(pmd)))
>>   #define pmd_mkold(pmd)		pte_pmd(pte_mkold(pmd_pte(pmd)))
>> @@ -501,8 +512,19 @@ static inline pmd_t pmd_mkdevmap(pmd_t pmd)
>>   #define pud_pfn(pud)		((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
>>   #define pfn_pud(pfn,prot)	__pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
>>   
>> -#define set_pmd_at(mm, addr, pmdp, pmd)	set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd))
>> -#define set_pud_at(mm, addr, pudp, pud)	set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud))
>> +static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
>> +			      pmd_t *pmdp, pmd_t pmd)
>> +{
>> +	page_table_check_pmd_set(mm, addr, pmdp, pmd);
>> +	return __set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd));
>> +}
>> +
>> +static inline void set_pud_at(struct mm_struct *mm, unsigned long addr,
>> +			      pud_t *pudp, pud_t pud)
>> +{
>> +	page_table_check_pud_set(mm, addr, pudp, pud);
>> +	return __set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud));
>> +}
>>   
>>   #define __p4d_to_phys(p4d)	__pte_to_phys(p4d_pte(p4d))
>>   #define __phys_to_p4d_val(phys)	__phys_to_pte_val(phys)
>> @@ -643,6 +665,24 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd)
>>   #define pud_present(pud)	pte_present(pud_pte(pud))
>>   #define pud_leaf(pud)		pud_sect(pud)
>>   #define pud_valid(pud)		pte_valid(pud_pte(pud))
>> +#define pud_user(pud)		pte_user(pud_pte(pud))
>> +
>> +#ifdef CONFIG_PAGE_TABLE_CHECK
>> +static inline bool pte_user_accessible_page(pte_t pte)
>> +{
>> +	return pte_present(pte) && (pte_user(pte) || pte_user_exec(pte));
>> +}
>> +
>> +static inline bool pmd_user_accessible_page(pmd_t pmd)
>> +{
>> +	return pmd_present(pmd) && (pmd_user(pmd) || pmd_user_exec(pmd));
>> +}
>> +
>> +static inline bool pud_user_accessible_page(pud_t pud)
>> +{
>> +	return pud_present(pud) && pud_user(pud);
>> +}
>> +#endif
>>   
>>   static inline void set_pud(pud_t *pudp, pud_t pud)
>>   {
>> @@ -872,11 +912,21 @@ static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
>>   }
>>   #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
>>   
>> +static inline pte_t __ptep_get_and_clear(struct mm_struct *mm,
>> +				       unsigned long address, pte_t *ptep)
>> +{
>> +	return __pte(xchg_relaxed(&pte_val(*ptep), 0));
>> +}
>> +
>>   #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
>>   static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
>>   				       unsigned long address, pte_t *ptep)
>>   {
>> -	return __pte(xchg_relaxed(&pte_val(*ptep), 0));
>> +	pte_t pte = __ptep_get_and_clear(mm, address, ptep);
>>
> 
> __ptep_get_and_clear() is not required. Please keep the __pte(xchg_relaxed(..),..)
> unchanged as in the case with pmdp_huge_get_and_clear() helper below.
> 
>   +
>> +	page_table_check_pte_clear(mm, address, pte);
>> +
>> +	return pte;
>>   }
>>   
>>   #ifdef CONFIG_TRANSPARENT_HUGEPAGE
>> @@ -884,7 +934,11 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
>>   static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
>>   					    unsigned long address, pmd_t *pmdp)
>>   {
>> -	return pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp));
>> +	pmd_t pmd = pte_pmd(__ptep_get_and_clear(mm, address, (pte_t *)pmdp));
>> +
>> +	page_table_check_pmd_clear(mm, address, pmd);
>> +
>> +	return pmd;
>>   }
>>   #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
>>   
>> @@ -918,6 +972,7 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm,
>>   static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
>>   		unsigned long address, pmd_t *pmdp, pmd_t pmd)
>>   {
>> +	page_table_check_pmd_set(vma->vm_mm, address, pmdp, pmd);
>>   	return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
>>   }
>>   #endif
> .
Anshuman Khandual April 25, 2022, 5:41 a.m. UTC | #3 
On 4/24/22 09:44, Tong Tiangen wrote:
> 
> 
> 在 2022/4/22 14:45, Anshuman Khandual 写道:
>> Please change the subject line as
>>
>> arm64/mm: Enable ARCH_SUPPORTS_PAGE_TABLE_CHECK
>>
>> OR
>>
>> arm64/mm: Subscribe ARCH_SUPPORTS_PAGE_TABLE_CHECK
>>
>> On 4/21/22 13:50, Tong Tiangen wrote:
>>> From: Kefeng Wang <wangkefeng.wang@huawei.com>
>>>
>>> As commit d283d422c6c4 ("x86: mm: add x86_64 support for page table
>>> check"), add some necessary page table check hooks into routines that
>>> modify user page tables.
>>
>> Please make the commit message comprehensive, which should include
>>
>> - Enabling ARCH_SUPPORTS_PAGE_TABLE_CHECK on arm64
>> - Adding all additional page table helpers required for PAGE_TABLE_CHECK
>> - Instrumenting existing page table helpers with page table check hooks
>>
> 
> Good suggestion, if i need to do a new version for some other reason i think it should be described more comprehensivel


This series needs revision to accommodate earlier comments.
Tong Tiangen April 25, 2022, 7:34 a.m. UTC | #4 
在 2022/4/25 13:41, Anshuman Khandual 写道:
> 
> 
> On 4/24/22 09:44, Tong Tiangen wrote:
>>
>>
>> 在 2022/4/22 14:45, Anshuman Khandual 写道:
>>> Please change the subject line as
>>>
>>> arm64/mm: Enable ARCH_SUPPORTS_PAGE_TABLE_CHECK
>>>
>>> OR
>>>
>>> arm64/mm: Subscribe ARCH_SUPPORTS_PAGE_TABLE_CHECK
>>>
>>> On 4/21/22 13:50, Tong Tiangen wrote:
>>>> From: Kefeng Wang <wangkefeng.wang@huawei.com>
>>>>
>>>> As commit d283d422c6c4 ("x86: mm: add x86_64 support for page table
>>>> check"), add some necessary page table check hooks into routines that
>>>> modify user page tables.
>>>
>>> Please make the commit message comprehensive, which should include
>>>
>>> - Enabling ARCH_SUPPORTS_PAGE_TABLE_CHECK on arm64
>>> - Adding all additional page table helpers required for PAGE_TABLE_CHECK
>>> - Instrumenting existing page table helpers with page table check hooks
>>>
>>
>> Good suggestion, if i need to do a new version for some other reason i think it should be described more comprehensivel
> 
> 
> This series needs revision to accommodate earlier comments.
> .

OK, Thanks.
diff mbox series

Patch

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 18a18a0e855d..c1509525ab8e 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -92,6 +92,7 @@  config ARM64
 	select ARCH_SUPPORTS_ATOMIC_RMW
 	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
 	select ARCH_SUPPORTS_NUMA_BALANCING
+	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
 	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
 	select ARCH_WANT_DEFAULT_BPF_JIT
 	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 930077f7b572..9f8f97a7cc7c 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -33,6 +33,7 @@ 
 #include <linux/mmdebug.h>
 #include <linux/mm_types.h>
 #include <linux/sched.h>
+#include <linux/page_table_check.h>
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 #define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
@@ -96,6 +97,7 @@  static inline pteval_t __phys_to_pte_val(phys_addr_t phys)
 #define pte_young(pte)		(!!(pte_val(pte) & PTE_AF))
 #define pte_special(pte)	(!!(pte_val(pte) & PTE_SPECIAL))
 #define pte_write(pte)		(!!(pte_val(pte) & PTE_WRITE))
+#define pte_user(pte)		(!!(pte_val(pte) & PTE_USER))
 #define pte_user_exec(pte)	(!(pte_val(pte) & PTE_UXN))
 #define pte_cont(pte)		(!!(pte_val(pte) & PTE_CONT))
 #define pte_devmap(pte)		(!!(pte_val(pte) & PTE_DEVMAP))
@@ -312,7 +314,7 @@  static inline void __check_racy_pte_update(struct mm_struct *mm, pte_t *ptep,
 		     __func__, pte_val(old_pte), pte_val(pte));
 }
 
-static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
+static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
 			      pte_t *ptep, pte_t pte)
 {
 	if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
@@ -343,6 +345,13 @@  static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
 	set_pte(ptep, pte);
 }
 
+static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
+			      pte_t *ptep, pte_t pte)
+{
+	page_table_check_pte_set(mm, addr, ptep, pte);
+	return __set_pte_at(mm, addr, ptep, pte);
+}
+
 /*
  * Huge pte definitions.
  */
@@ -454,6 +463,8 @@  static inline int pmd_trans_huge(pmd_t pmd)
 #define pmd_dirty(pmd)		pte_dirty(pmd_pte(pmd))
 #define pmd_young(pmd)		pte_young(pmd_pte(pmd))
 #define pmd_valid(pmd)		pte_valid(pmd_pte(pmd))
+#define pmd_user(pmd)		pte_user(pmd_pte(pmd))
+#define pmd_user_exec(pmd)	pte_user_exec(pmd_pte(pmd))
 #define pmd_cont(pmd)		pte_cont(pmd_pte(pmd))
 #define pmd_wrprotect(pmd)	pte_pmd(pte_wrprotect(pmd_pte(pmd)))
 #define pmd_mkold(pmd)		pte_pmd(pte_mkold(pmd_pte(pmd)))
@@ -501,8 +512,19 @@  static inline pmd_t pmd_mkdevmap(pmd_t pmd)
 #define pud_pfn(pud)		((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
 #define pfn_pud(pfn,prot)	__pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
 
-#define set_pmd_at(mm, addr, pmdp, pmd)	set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd))
-#define set_pud_at(mm, addr, pudp, pud)	set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud))
+static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
+			      pmd_t *pmdp, pmd_t pmd)
+{
+	page_table_check_pmd_set(mm, addr, pmdp, pmd);
+	return __set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd));
+}
+
+static inline void set_pud_at(struct mm_struct *mm, unsigned long addr,
+			      pud_t *pudp, pud_t pud)
+{
+	page_table_check_pud_set(mm, addr, pudp, pud);
+	return __set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud));
+}
 
 #define __p4d_to_phys(p4d)	__pte_to_phys(p4d_pte(p4d))
 #define __phys_to_p4d_val(phys)	__phys_to_pte_val(phys)
@@ -643,6 +665,24 @@  static inline unsigned long pmd_page_vaddr(pmd_t pmd)
 #define pud_present(pud)	pte_present(pud_pte(pud))
 #define pud_leaf(pud)		pud_sect(pud)
 #define pud_valid(pud)		pte_valid(pud_pte(pud))
+#define pud_user(pud)		pte_user(pud_pte(pud))
+
+#ifdef CONFIG_PAGE_TABLE_CHECK
+static inline bool pte_user_accessible_page(pte_t pte)
+{
+	return pte_present(pte) && (pte_user(pte) || pte_user_exec(pte));
+}
+
+static inline bool pmd_user_accessible_page(pmd_t pmd)
+{
+	return pmd_present(pmd) && (pmd_user(pmd) || pmd_user_exec(pmd));
+}
+
+static inline bool pud_user_accessible_page(pud_t pud)
+{
+	return pud_present(pud) && pud_user(pud);
+}
+#endif
 
 static inline void set_pud(pud_t *pudp, pud_t pud)
 {
@@ -872,11 +912,21 @@  static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
 }
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
+static inline pte_t __ptep_get_and_clear(struct mm_struct *mm,
+				       unsigned long address, pte_t *ptep)
+{
+	return __pte(xchg_relaxed(&pte_val(*ptep), 0));
+}
+
 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
 				       unsigned long address, pte_t *ptep)
 {
-	return __pte(xchg_relaxed(&pte_val(*ptep), 0));
+	pte_t pte = __ptep_get_and_clear(mm, address, ptep);
+
+	page_table_check_pte_clear(mm, address, pte);
+
+	return pte;
 }
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
@@ -884,7 +934,11 @@  static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
 static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
 					    unsigned long address, pmd_t *pmdp)
 {
-	return pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp));
+	pmd_t pmd = pte_pmd(__ptep_get_and_clear(mm, address, (pte_t *)pmdp));
+
+	page_table_check_pmd_clear(mm, address, pmd);
+
+	return pmd;
 }
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
@@ -918,6 +972,7 @@  static inline void pmdp_set_wrprotect(struct mm_struct *mm,
 static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
 		unsigned long address, pmd_t *pmdp, pmd_t pmd)
 {
+	page_table_check_pmd_set(vma->vm_mm, address, pmdp, pmd);
 	return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
 }
 #endif