[PATCH v3 8/8] x86/module: enable ROX caches for module text
From: Mike Rapoport <rppt@kernel.org>
Date: 2024-09-09 06:49:57
Also in:
bpf, linux-alpha, linux-arch, linux-m68k, linux-mips, linux-mm, linux-modules, linux-riscv, linux-sh, linux-um, linuxppc-dev, lkml, loongarch, sparclinux
Subsystem:
the rest, x86 architecture (32-bit and 64-bit), x86 mm · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, Andy Lutomirski, Peter Zijlstra
From: "Mike Rapoport (Microsoft)" <rppt@kernel.org> Enable execmem's cache of PMD_SIZE'ed pages mapped as ROX for module text allocations. Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> --- arch/x86/mm/init.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-)
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index eb503f53c319..a0ec99fb9385 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c@@ -1053,6 +1053,15 @@ unsigned long arch_max_swapfile_size(void) #ifdef CONFIG_EXECMEM static struct execmem_info execmem_info __ro_after_init; +static void execmem_fill_trapping_insns(void *ptr, size_t size, bool writeable) +{ + /* fill memory with INT3 instructions */ + if (writeable) + memset(ptr, INT3_INSN_OPCODE, size); + else + text_poke_set(ptr, INT3_INSN_OPCODE, size); +} + struct execmem_info __init *execmem_arch_setup(void) { unsigned long start, offset = 0;
@@ -1063,8 +1072,23 @@ struct execmem_info __init *execmem_arch_setup(void) start = MODULES_VADDR + offset; execmem_info = (struct execmem_info){ + .fill_trapping_insns = execmem_fill_trapping_insns, .ranges = { - [EXECMEM_DEFAULT] = { + [EXECMEM_MODULE_TEXT] = { + .flags = EXECMEM_KASAN_SHADOW | EXECMEM_ROX_CACHE, + .start = start, + .end = MODULES_END, + .pgprot = PAGE_KERNEL_ROX, + .alignment = MODULE_ALIGN, + }, + [EXECMEM_KPROBES ... EXECMEM_BPF] = { + .flags = EXECMEM_KASAN_SHADOW, + .start = start, + .end = MODULES_END, + .pgprot = PAGE_KERNEL, + .alignment = MODULE_ALIGN, + }, + [EXECMEM_MODULE_DATA] = { .flags = EXECMEM_KASAN_SHADOW, .start = start, .end = MODULES_END,
--
2.43.0