arm64: Introduce execute-only page access permissions

[karo-tx-linux.git] / arch / arm64 / mm / fault.c

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index c23751b0612033f56533955788eabefa6c5fd39e..89c6763d5e7e678b0623ef9ecd1d464c3a256ebb 100644 (file)
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -32,6 +32,7 @@
 
 #include <asm/exception.h>
 #include <asm/debug-monitors.h>
+#include <asm/esr.h>
 #include <asm/system_misc.h>
 #include <asm/pgtable.h>
 #include <asm/tlbflush.h>
@@ -123,6 +124,7 @@ static void __do_user_fault(struct task_struct *tsk, unsigned long addr,
        }
 
        tsk->thread.fault_address = addr;
+       tsk->thread.fault_code = esr;
        si.si_signo = sig;
        si.si_errno = 0;
        si.si_code = code;
@@ -148,8 +150,6 @@ static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *re
 #define VM_FAULT_BADMAP                0x010000
 #define VM_FAULT_BADACCESS     0x020000
 
-#define ESR_WRITE              (1 << 6)
-#define ESR_CM                 (1 << 8)
 #define ESR_LNX_EXEC           (1 << 24)
 
 static int __do_page_fault(struct mm_struct *mm, unsigned long addr,
@@ -173,8 +173,7 @@ static int __do_page_fault(struct mm_struct *mm, unsigned long addr,
 good_area:
        /*
         * Check that the permissions on the VMA allow for the fault which
-        * occurred. If we encountered a write or exec fault, we must have
-        * appropriate permissions, otherwise we allow any permission.
+        * occurred.
         */
        if (!(vma->vm_flags & vm_flags)) {
                fault = VM_FAULT_BADACCESS;
@@ -196,7 +195,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
        struct task_struct *tsk;
        struct mm_struct *mm;
        int fault, sig, code;
-       unsigned long vm_flags = VM_READ | VM_WRITE | VM_EXEC;
+       unsigned long vm_flags = VM_READ | VM_WRITE;
        unsigned int mm_flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
 
        tsk = current;
@@ -218,7 +217,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
 
        if (esr & ESR_LNX_EXEC) {
                vm_flags = VM_EXEC;
-       } else if ((esr & ESR_WRITE) && !(esr & ESR_CM)) {
+       } else if ((esr & ESR_EL1_WRITE) && !(esr & ESR_EL1_CM)) {
                vm_flags = VM_WRITE;
                mm_flags |= FAULT_FLAG_WRITE;
        }
@@ -525,7 +524,7 @@ asmlinkage int __exception do_debug_exception(unsigned long addr,
        info.si_errno = 0;
        info.si_code  = inf->code;
        info.si_addr  = (void __user *)addr;
-       arm64_notify_die("", regs, &info, esr);
+       arm64_notify_die("", regs, &info, 0);
 
        return 0;
 }