diff options
| author | Peter Maydell <peter.maydell@linaro.org> | 2017-07-27 11:59:07 +0100 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2017-07-31 13:09:18 +0100 |
| commit | bf446a11dfb17ae7d8ed2b61a2444804eb458075 (patch) | |
| tree | 0e322d33916bccce25d8869294e5fbfd914f84b6 /target/arm | |
| parent | 38aaa60ca464b48e6feef346709e97335d01b289 (diff) | |
target/arm: Don't allow guest to make System space executable for M profile
For an M profile v7PMSA, the system space (0xe0000000 - 0xffffffff) can
never be executable, even if the guest tries to set the MPU registers
up that way. Enforce this restriction.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 1501153150-19984-3-git-send-email-peter.maydell@linaro.org
Diffstat (limited to 'target/arm')
| -rw-r--r-- | target/arm/helper.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/target/arm/helper.c b/target/arm/helper.c index 3d6057503d..f0299c5282 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -8251,6 +8251,14 @@ static inline bool m_is_ppb_region(CPUARMState *env, uint32_t address) extract32(address, 20, 12) == 0xe00; } +static inline bool m_is_system_region(CPUARMState *env, uint32_t address) +{ + /* True if address is in the M profile system region + * 0xe0000000 - 0xffffffff + */ + return arm_feature(env, ARM_FEATURE_M) && extract32(address, 29, 3) == 0x7; +} + static bool get_phys_addr_pmsav7(CPUARMState *env, uint32_t address, int access_type, ARMMMUIdx mmu_idx, hwaddr *phys_ptr, int *prot, uint32_t *fsr) @@ -8354,6 +8362,12 @@ static bool get_phys_addr_pmsav7(CPUARMState *env, uint32_t address, get_phys_addr_pmsav7_default(env, mmu_idx, address, prot); } else { /* a MPU hit! */ uint32_t ap = extract32(env->pmsav7.dracr[n], 8, 3); + uint32_t xn = extract32(env->pmsav7.dracr[n], 12, 1); + + if (m_is_system_region(env, address)) { + /* System space is always execute never */ + xn = 1; + } if (is_user) { /* User mode AP bit decoding */ switch (ap) { @@ -8394,7 +8408,7 @@ static bool get_phys_addr_pmsav7(CPUARMState *env, uint32_t address, } /* execute never */ - if (env->pmsav7.dracr[n] & (1 << 12)) { + if (xn) { *prot &= ~PAGE_EXEC; } } |