Make module_alloc() use PAGE_KERNEL protections instead of
PAGE_KERNEL_EXEX if Strict Module RWX is enabled.

Signed-off-by: Jordan Niethe <jniet...@gmail.com>
---
v14: - Split out from powerpc: Set ARCH_HAS_STRICT_MODULE_RWX
     - Add and use strict_module_rwx_enabled() helper
---
 arch/powerpc/include/asm/mmu.h | 5 +++++
 arch/powerpc/kernel/module.c   | 4 +++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h
index 998fe01dd1a8..27016b98ecb2 100644
--- a/arch/powerpc/include/asm/mmu.h
+++ b/arch/powerpc/include/asm/mmu.h
@@ -345,6 +345,11 @@ static inline bool strict_kernel_rwx_enabled(void)
        return false;
 }
 #endif
+
+static inline bool strict_module_rwx_enabled(void)
+{
+       return IS_ENABLED(CONFIG_STRICT_MODULE_RWX) && 
strict_kernel_rwx_enabled();
+}
 #endif /* !__ASSEMBLY__ */
 
 /* The kernel use the constants below to index in the page sizes array.
diff --git a/arch/powerpc/kernel/module.c b/arch/powerpc/kernel/module.c
index 3f35c8d20be7..ed04a3ba66fe 100644
--- a/arch/powerpc/kernel/module.c
+++ b/arch/powerpc/kernel/module.c
@@ -92,12 +92,14 @@ int module_finalize(const Elf_Ehdr *hdr,
 static __always_inline void *
 __module_alloc(unsigned long size, unsigned long start, unsigned long end)
 {
+       pgprot_t prot = strict_module_rwx_enabled() ? PAGE_KERNEL : 
PAGE_KERNEL_EXEC;
+
        /*
         * Don't do huge page allocations for modules yet until more testing
         * is done. STRICT_MODULE_RWX may require extra work to support this
         * too.
         */
-       return __vmalloc_node_range(size, 1, start, end, GFP_KERNEL, 
PAGE_KERNEL_EXEC,
+       return __vmalloc_node_range(size, 1, start, end, GFP_KERNEL, prot,
                                    VM_FLUSH_RESET_PERMS | VM_NO_HUGE_VMAP,
                                    NUMA_NO_NODE, __builtin_return_address(0));
 }
-- 
2.25.1

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