[v3,1/5] Hardening x86: Forbid writes to read-only memory pages of a process

Commit Message

Lev R. Oshvang . April 13, 2020, 3:32 p.m. UTC

Signed-off-by: Lev Olshvang <[e-mail]>
---
 arch/x86/include/asm/mmu_context.h | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

Patch

diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index 701a7367babf..4e55370e48e8 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -5,7 +5,6 @@ 
 #include <asm/desc.h>
 #include <linux/atomic.h>
 #include <linux/mm_types.h>
-#include <linux/printk.h>
 #include <linux/pkeys.h>
 
 #include <trace/events/tlb.h>
@@ -217,12 +216,7 @@  static inline void arch_unmap(struct mm_struct *mm, unsigned long start,
 static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
 		bool write, bool execute, bool foreign)
 {
-	if (unlikely(!vma_write_allowed(vma, write, execute, foreign))) {
-		pr_err_once("Error : PID[%d] %s writes to read only memory\n",
-			current->tgid, current->comm);
-		return false;
-	}
-	/* Don't check PKRU since pkeys never affect instruction fetches */
+	/* pkeys never affect instruction fetches */
 	if (execute)
 		return true;
 	/* allow access if the VMA is not one from this process */