[PATCH v3 09/10] riscv: module: Create module allocations without exec permissions

From: Jisheng Zhang
Date: Mon Apr 12 2021 - 12:30:39 EST


From: Jisheng Zhang <jszhang@xxxxxxxxxx>

The core code manages the executable permissions of code regions of
modules explicitly, it is not necessary to create the module vmalloc
regions with RWX permissions. Create them with RW- permissions instead.

Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx>
---
arch/riscv/kernel/module.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c
index 104fba889cf7..e89367bba7c9 100644
--- a/arch/riscv/kernel/module.c
+++ b/arch/riscv/kernel/module.c
@@ -407,14 +407,20 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
return 0;
}

-#if defined(CONFIG_MMU) && defined(CONFIG_64BIT)
+#ifdef CONFIG_MMU
+
+#ifdef CONFIG_64BIT
#define VMALLOC_MODULE_START \
max(PFN_ALIGN((unsigned long)&_end - SZ_2G), VMALLOC_START)
+#else
+#define VMALLOC_MODULE_START VMALLOC_START
+#endif
+
void *module_alloc(unsigned long size)
{
return __vmalloc_node_range(size, 1, VMALLOC_MODULE_START,
VMALLOC_END, GFP_KERNEL,
- PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
+ PAGE_KERNEL, 0, NUMA_NO_NODE,
__builtin_return_address(0));
}
#endif
--
2.31.0