Commit f4e1dbc5 authored Mar 30, 2020 by Peter Maydell

target/arm: PSTATE.PAN should not clear exec bits



Our implementation of the PSTATE.PAN bit incorrectly cleared all
access permission bits for privileged access to memory which is
user-accessible.  It should only affect the privileged read and write
permissions; execute permission is dealt with via XN/PXN instead.

Fixes: 81636b70
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200330170651.20901-1-peter.maydell@linaro.org

parent 8a2b76ff

target/arm/helper.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -10025,10 +10025,12 @@ static int get_S1prot(CPUARMState *env, ARMMMUIdx mmu_idx, bool is_aa64,
		prot_rw = user_rw;
		} else {
		if (user_rw && regime_is_pan(env, mmu_idx)) {
		return 0;
		}
		/* PAN forbids data accesses but doesn't affect insn fetch */
		prot_rw = 0;
		} else {
		prot_rw = simple_ap_to_rw_prot_is_user(ap, false);
		}
		}

		if (ns && arm_is_secure(env) && (env->cp15.scr_el3 & SCR_SIF)) {
		return prot_rw;