mm: Add address parameter to arch_validate_prot()

A protection flag may not be valid across entire address space and hence arch_validate_prot() might need the address a protection bit is being set on to ensure it is a valid protection flag. For example, sparc processors support memory corruption detection (as part of ADI feature) flag on memory addresses mapped on to physical RAM but not on PFN mapped pages or addresses mapped on to devices. This patch adds address to the parameters being passed to arch_validate_prot() so protection bits can be validated in the relevant context. Signed-off-by: Khalid Aziz <[email protected]> Cc: Khalid Aziz <[email protected]> Reviewed-by: Anthony Yznaga <[email protected]> Acked-by: Michael Ellerman <[email protected]> (powerpc) Acked-by: Andrew Morton <[email protected]> Signed-off-by: David S. Miller <[email protected]>
kawasaki · Mar 18, 2018 · 9035cf9 · 9035cf9
1 parent c6202ca
commit 9035cf9
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Showing 4 changed files with 5 additions and 5 deletions.
diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h
@@ -43,15 +43,15 @@ static inline pgprot_t arch_vm_get_page_prot(unsigned long vm_flags)
 }
 #define arch_vm_get_page_prot(vm_flags) arch_vm_get_page_prot(vm_flags)
 
-static inline bool arch_validate_prot(unsigned long prot)
+static inline bool arch_validate_prot(unsigned long prot, unsigned long addr)
 {
 	if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM | PROT_SAO))
 		return false;
 	if ((prot & PROT_SAO) && !cpu_has_feature(CPU_FTR_SAO))
 		return false;
 	return true;
 }
-#define arch_validate_prot(prot) arch_validate_prot(prot)
+#define arch_validate_prot arch_validate_prot
 
 #endif /* CONFIG_PPC64 */
 #endif	/* _ASM_POWERPC_MMAN_H */
diff --git a/arch/powerpc/kernel/syscalls.c b/arch/powerpc/kernel/syscalls.c
@@ -48,7 +48,7 @@ static inline long do_mmap2(unsigned long addr, size_t len,
 {
 	long ret = -EINVAL;
 
-	if (!arch_validate_prot(prot))
+	if (!arch_validate_prot(prot, addr))
 		goto out;
 
 	if (shift) {

diff --git a/include/linux/mman.h b/include/linux/mman.h
@@ -92,7 +92,7 @@ static inline void vm_unacct_memory(long pages)
  *
  * Returns true if the prot flags are valid
  */
-static inline bool arch_validate_prot(unsigned long prot)
+static inline bool arch_validate_prot(unsigned long prot, unsigned long addr)
 {
 	return (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM)) == 0;
 }

diff --git a/mm/mprotect.c b/mm/mprotect.c
@@ -417,7 +417,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
 	end = start + len;
 	if (end <= start)
 		return -ENOMEM;
-	if (!arch_validate_prot(prot))
+	if (!arch_validate_prot(prot, start))
 		return -EINVAL;
 
 	reqprot = prot;