From 10b81272b305da375c3c3e9ec86f2e35df702f2e Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Mon, 14 Jun 2021 20:07:44 -0700 Subject: [PATCH] linux-user/s390x: Save and restore psw.mask properly At present, we're referencing env->psw.mask directly, which fails to ensure that env->cc_op is incorporated or updated. Use s390_cpu_{set_psw,get_psw_mask} to fix this. Mirror the kernel's cleaning of the psw.mask in save_sigregs and restore_sigregs. Ignore PSW_MASK_RI for now, as qemu does not support that. Signed-off-by: Richard Henderson Reviewed-by: David Hildenbrand Tested-by: jonathan.albrecht Tested-by: Message-Id: <20210615030744.1252385-6-richard.henderson@linaro.org> Signed-off-by: Cornelia Huck --- linux-user/s390x/signal.c | 37 ++++++++++++++++++++++++++++++++----- 1 file changed, 32 insertions(+), 5 deletions(-) diff --git a/linux-user/s390x/signal.c b/linux-user/s390x/signal.c index ef136dae33..bf8a8fbfe9 100644 --- a/linux-user/s390x/signal.c +++ b/linux-user/s390x/signal.c @@ -112,15 +112,23 @@ get_sigframe(struct target_sigaction *ka, CPUS390XState *env, size_t frame_size) return (sp - frame_size) & -8ul; } +#define PSW_USER_BITS (PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | \ + PSW_MASK_MCHECK | PSW_MASK_PSTATE | PSW_ASC_PRIMARY) +#define PSW_MASK_USER (PSW_MASK_ASC | PSW_MASK_CC | PSW_MASK_PM | \ + PSW_MASK_64 | PSW_MASK_32) + static void save_sigregs(CPUS390XState *env, target_sigregs *sregs) { + uint64_t psw_mask = s390_cpu_get_psw_mask(env); int i; /* * Copy a 'clean' PSW mask to the user to avoid leaking * information about whether PER is currently on. + * TODO: qemu does not support PSW_MASK_RI; it will never be set. */ - __put_user(env->psw.mask, &sregs->regs.psw.mask); + psw_mask = PSW_USER_BITS | (psw_mask & PSW_MASK_USER); + __put_user(psw_mask, &sregs->regs.psw.mask); __put_user(env->psw.addr, &sregs->regs.psw.addr); for (i = 0; i < 16; i++) { @@ -289,7 +297,7 @@ void setup_rt_frame(int sig, struct target_sigaction *ka, static void restore_sigregs(CPUS390XState *env, target_sigregs *sc) { - target_ulong prev_addr; + uint64_t prev_addr, prev_mask, mask, addr; int i; for (i = 0; i < 16; i++) { @@ -297,9 +305,28 @@ static void restore_sigregs(CPUS390XState *env, target_sigregs *sc) } prev_addr = env->psw.addr; - __get_user(env->psw.mask, &sc->regs.psw.mask); - __get_user(env->psw.addr, &sc->regs.psw.addr); - trace_user_s390x_restore_sigregs(env, env->psw.addr, prev_addr); + __get_user(mask, &sc->regs.psw.mask); + __get_user(addr, &sc->regs.psw.addr); + trace_user_s390x_restore_sigregs(env, addr, prev_addr); + + /* + * Use current psw.mask to preserve PER bit. + * TODO: + * if (!is_ri_task(current) && (user_sregs.regs.psw.mask & PSW_MASK_RI)) + * return -EINVAL; + * Simply do not allow it to be set in mask. + */ + prev_mask = s390_cpu_get_psw_mask(env); + mask = (prev_mask & ~PSW_MASK_USER) | (mask & PSW_MASK_USER); + /* Check for invalid user address space control. */ + if ((mask & PSW_MASK_ASC) == PSW_ASC_HOME) { + mask = (mask & ~PSW_MASK_ASC) | PSW_ASC_PRIMARY; + } + /* Check for invalid amode. */ + if (mask & PSW_MASK_64) { + mask |= PSW_MASK_32; + } + s390_cpu_set_psw(env, mask, addr); for (i = 0; i < 16; i++) { __get_user(env->aregs[i], &sc->regs.acrs[i]);