static_call: Add some validation (6c3fce79) · Commits · 戴 / test

arch/x86/kernel/static_call.c

+26 −2

Original line number	Diff line number	Diff line
		@@ -41,6 +41,26 @@ static void __static_call_transform(void insn, enum insn_type type, void func)
		text_poke_bp(insn, code, size, NULL);
		}

		static void __static_call_validate(void *insn, bool tail)
		{
		u8 opcode = (u8 )insn;

		if (tail) {
		if (opcode == JMP32_INSN_OPCODE \|\|
		opcode == RET_INSN_OPCODE)
		return;
		} else {
		if (opcode == CALL_INSN_OPCODE \|\|
		!memcmp(insn, ideal_nops[NOP_ATOMIC5], 5))
		return;
		}

		/*
		* If we ever trigger this, our text is corrupt, we'll probably not live long.
		*/
		WARN_ONCE(1, "unexpected static_call insn opcode 0x%x at %pS\n", opcode, insn);
		}

		static inline enum insn_type __sc_insn(bool null, bool tail)
		{
		/*
		@@ -60,11 +80,15 @@ void arch_static_call_transform(void site, void tramp, void *func, bool tail)
		{
		mutex_lock(&text_mutex);

		if (tramp)
		if (tramp) {
		__static_call_validate(tramp, true);
		__static_call_transform(tramp, __sc_insn(!func, true), func);
		}

		if (IS_ENABLED(CONFIG_HAVE_STATIC_CALL_INLINE) && site)
		if (IS_ENABLED(CONFIG_HAVE_STATIC_CALL_INLINE) && site) {
		__static_call_validate(site, tail);
		__static_call_transform(site, __sc_insn(!func, tail), func);
		}

		mutex_unlock(&text_mutex);
		}