| Message ID | 20200330170651.20901-1-peter.maydell@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [for-5.0] target/arm: PSTATE.PAN should not clear exec bits | expand |
On 3/30/20 10:06 AM, Peter Maydell wrote: > 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: 81636b70c226dc27d7ebc8d > Signed-off-by: Peter Maydell <peter.maydell@linaro.org> > --- > Compare the pseudocode AArch64.CheckPermission(). > --- > target/arm/helper.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) Oops, Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
diff --git a/target/arm/helper.c b/target/arm/helper.c index 163c91a1ccd..ed7eb8ab54e 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -10025,9 +10025,11 @@ 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); } - prot_rw = simple_ap_to_rw_prot_is_user(ap, false); } if (ns && arm_is_secure(env) && (env->cp15.scr_el3 & SCR_SIF)) {
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: 81636b70c226dc27d7ebc8d Signed-off-by: Peter Maydell <peter.maydell@linaro.org> --- Compare the pseudocode AArch64.CheckPermission(). --- target/arm/helper.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) -- 2.20.1