3 files changed, 26 insertions, 2 deletions

diff --git a/arch/mips/include/asm/elf.h b/arch/mips/include/asm/elf.h
index ede8c4ff56f7..2b3dc2973670 100644
--- a/arch/mips/include/asm/elf.h
+++ b/arch/mips/include/asm/elf.h
@@ -499,4 +499,7 @@ extern int arch_check_elf(void *ehdr, bool has_interpreter, void *interp_ehdr,
 extern void mips_set_personality_nan(struct arch_elf_state *state);
 extern void mips_set_personality_fp(struct arch_elf_state *state);
 
+#define elf_read_implies_exec(ex, stk) mips_elf_read_implies_exec(&(ex), stk)
+extern int mips_elf_read_implies_exec(void *elf_ex, int exstack);
+
 #endif /* _ASM_ELF_H */
diff --git a/arch/mips/include/asm/page.h b/arch/mips/include/asm/page.h
index 21ed7150fec3..74cb004c2868 100644
--- a/arch/mips/include/asm/page.h
+++ b/arch/mips/include/asm/page.h
@@ -229,8 +229,10 @@ extern int __virt_addr_valid(const volatile void *kaddr);
 #define virt_addr_valid(kaddr)                                          \
         __virt_addr_valid((const volatile void *) (kaddr))
 
-#define VM_DATA_DEFAULT_FLAGS   (VM_READ | VM_WRITE | VM_EXEC | \
-                                 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+#define VM_DATA_DEFAULT_FLAGS \
+        (VM_READ | VM_WRITE | \
+         ((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0) | \
+         VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
 
 #define UNCAC_ADDR(addr)        ((addr) - PAGE_OFFSET + UNCAC_BASE)
 #define CAC_ADDR(addr)          ((addr) - UNCAC_BASE + PAGE_OFFSET)
diff --git a/arch/mips/kernel/elf.c b/arch/mips/kernel/elf.c
index 891f5ee63983..824b0373ba71 100644
--- a/arch/mips/kernel/elf.c
+++ b/arch/mips/kernel/elf.c
@@ -8,9 +8,12 @@
  * option) any later version.
  */
 
+#include <linux/binfmts.h>
 #include <linux/elf.h>
+#include <linux/export.h>
 #include <linux/sched.h>
 
+#include <asm/cpu-features.h>
 #include <asm/cpu-info.h>
 
 /* Whether to accept legacy-NaN and 2008-NaN user binaries.  */
@@ -326,3 +329,19 @@ void mips_set_personality_nan(struct arch_elf_state *state)
                 BUG();
         }
 }
+
+int mips_elf_read_implies_exec(void *elf_ex, int exstack)
+{
+        if (exstack != EXSTACK_DISABLE_X) {
+                /* The binary doesn't request a non-executable stack */
+                return 1;
+        }
+
+        if (!cpu_has_rixi) {
+                /* The CPU doesn't support non-executable memory */
+                return 1;
+        }
+
+        return 0;
+}
+EXPORT_SYMBOL(mips_elf_read_implies_exec);