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-rw-r--r--arch/x86/include/asm/mmu_context.h7
-rw-r--r--arch/x86/include/asm/mpx.h41
-rw-r--r--arch/x86/include/asm/processor.h18
-rw-r--r--arch/x86/kernel/setup.c2
-rw-r--r--arch/x86/kernel/traps.c85
-rw-r--r--arch/x86/mm/mpx.c223
-rw-r--r--fs/exec.c2
-rw-r--r--include/asm-generic/mmu_context.h5
-rw-r--r--include/linux/mm_types.h4
-rw-r--r--include/uapi/linux/prctl.h6
-rw-r--r--kernel/sys.c12
11 files changed, 399 insertions, 6 deletions
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index 166af2a8e865..0b0ba91ff1ef 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -10,6 +10,7 @@
#include <asm/pgalloc.h>
#include <asm/tlbflush.h>
#include <asm/paravirt.h>
+#include <asm/mpx.h>
#ifndef CONFIG_PARAVIRT
#include <asm-generic/mm_hooks.h>
@@ -102,4 +103,10 @@ do { \
} while (0)
#endif
+static inline void arch_bprm_mm_init(struct mm_struct *mm,
+ struct vm_area_struct *vma)
+{
+ mpx_mm_init(mm);
+}
+
#endif /* _ASM_X86_MMU_CONTEXT_H */
diff --git a/arch/x86/include/asm/mpx.h b/arch/x86/include/asm/mpx.h
index 35bcb1cddf40..05eecbf8a484 100644
--- a/arch/x86/include/asm/mpx.h
+++ b/arch/x86/include/asm/mpx.h
@@ -5,6 +5,14 @@
#include <asm/ptrace.h>
#include <asm/insn.h>
+/*
+ * NULL is theoretically a valid place to put the bounds
+ * directory, so point this at an invalid address.
+ */
+#define MPX_INVALID_BOUNDS_DIR ((void __user *)-1)
+#define MPX_BNDCFG_ENABLE_FLAG 0x1
+#define MPX_BD_ENTRY_VALID_FLAG 0x1
+
#ifdef CONFIG_X86_64
/* upper 28 bits [47:20] of the virtual address in 64-bit used to
@@ -18,6 +26,7 @@
#define MPX_BT_ENTRY_OFFSET 17
#define MPX_BT_ENTRY_SHIFT 5
#define MPX_IGN_BITS 3
+#define MPX_BD_ENTRY_TAIL 3
#else
@@ -26,23 +35,55 @@
#define MPX_BT_ENTRY_OFFSET 10
#define MPX_BT_ENTRY_SHIFT 4
#define MPX_IGN_BITS 2
+#define MPX_BD_ENTRY_TAIL 2
#endif
#define MPX_BD_SIZE_BYTES (1UL<<(MPX_BD_ENTRY_OFFSET+MPX_BD_ENTRY_SHIFT))
#define MPX_BT_SIZE_BYTES (1UL<<(MPX_BT_ENTRY_OFFSET+MPX_BT_ENTRY_SHIFT))
+#define MPX_BNDSTA_TAIL 2
+#define MPX_BNDCFG_TAIL 12
+#define MPX_BNDSTA_ADDR_MASK (~((1UL<<MPX_BNDSTA_TAIL)-1))
+#define MPX_BNDCFG_ADDR_MASK (~((1UL<<MPX_BNDCFG_TAIL)-1))
+#define MPX_BT_ADDR_MASK (~((1UL<<MPX_BD_ENTRY_TAIL)-1))
+
+#define MPX_BNDCFG_ADDR_MASK (~((1UL<<MPX_BNDCFG_TAIL)-1))
#define MPX_BNDSTA_ERROR_CODE 0x3
#ifdef CONFIG_X86_INTEL_MPX
siginfo_t *mpx_generate_siginfo(struct pt_regs *regs,
struct xsave_struct *xsave_buf);
+int mpx_handle_bd_fault(struct xsave_struct *xsave_buf);
+static inline int kernel_managing_mpx_tables(struct mm_struct *mm)
+{
+ return (mm->bd_addr != MPX_INVALID_BOUNDS_DIR);
+}
+static inline void mpx_mm_init(struct mm_struct *mm)
+{
+ /*
+ * NULL is theoretically a valid place to put the bounds
+ * directory, so point this at an invalid address.
+ */
+ mm->bd_addr = MPX_INVALID_BOUNDS_DIR;
+}
#else
static inline siginfo_t *mpx_generate_siginfo(struct pt_regs *regs,
struct xsave_struct *xsave_buf)
{
return NULL;
}
+static inline int mpx_handle_bd_fault(struct xsave_struct *xsave_buf)
+{
+ return -EINVAL;
+}
+static inline int kernel_managing_mpx_tables(struct mm_struct *mm)
+{
+ return 0;
+}
+static inline void mpx_mm_init(struct mm_struct *mm)
+{
+}
#endif /* CONFIG_X86_INTEL_MPX */
#endif /* _ASM_X86_MPX_H */
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 6571aaabacb9..9617a1716813 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -954,6 +954,24 @@ extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
extern int get_tsc_mode(unsigned long adr);
extern int set_tsc_mode(unsigned int val);
+/* Register/unregister a process' MPX related resource */
+#define MPX_ENABLE_MANAGEMENT(tsk) mpx_enable_management((tsk))
+#define MPX_DISABLE_MANAGEMENT(tsk) mpx_disable_management((tsk))
+
+#ifdef CONFIG_X86_INTEL_MPX
+extern int mpx_enable_management(struct task_struct *tsk);
+extern int mpx_disable_management(struct task_struct *tsk);
+#else
+static inline int mpx_enable_management(struct task_struct *tsk)
+{
+ return -EINVAL;
+}
+static inline int mpx_disable_management(struct task_struct *tsk)
+{
+ return -EINVAL;
+}
+#endif /* CONFIG_X86_INTEL_MPX */
+
extern u16 amd_get_nb_id(int cpu);
static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index ab08aa2276fb..214245d6b996 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -960,6 +960,8 @@ void __init setup_arch(char **cmdline_p)
init_mm.end_data = (unsigned long) _edata;
init_mm.brk = _brk_end;
+ mpx_mm_init(&init_mm);
+
code_resource.start = __pa_symbol(_text);
code_resource.end = __pa_symbol(_etext)-1;
data_resource.start = __pa_symbol(_etext);
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 0d0e922fafc1..651d5d4f7558 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -60,6 +60,7 @@
#include <asm/fixmap.h>
#include <asm/mach_traps.h>
#include <asm/alternative.h>
+#include <asm/mpx.h>
#ifdef CONFIG_X86_64
#include <asm/x86_init.h>
@@ -228,7 +229,6 @@ dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \
DO_ERROR(X86_TRAP_DE, SIGFPE, "divide error", divide_error)
DO_ERROR(X86_TRAP_OF, SIGSEGV, "overflow", overflow)
-DO_ERROR(X86_TRAP_BR, SIGSEGV, "bounds", bounds)
DO_ERROR(X86_TRAP_UD, SIGILL, "invalid opcode", invalid_op)
DO_ERROR(X86_TRAP_OLD_MF, SIGFPE, "coprocessor segment overrun",coprocessor_segment_overrun)
DO_ERROR(X86_TRAP_TS, SIGSEGV, "invalid TSS", invalid_TSS)
@@ -278,6 +278,89 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code)
}
#endif
+dotraplinkage void do_bounds(struct pt_regs *regs, long error_code)
+{
+ struct task_struct *tsk = current;
+ struct xsave_struct *xsave_buf;
+ enum ctx_state prev_state;
+ struct bndcsr *bndcsr;
+ siginfo_t *info;
+
+ prev_state = exception_enter();
+ if (notify_die(DIE_TRAP, "bounds", regs, error_code,
+ X86_TRAP_BR, SIGSEGV) == NOTIFY_STOP)
+ goto exit;
+ conditional_sti(regs);
+
+ if (!user_mode(regs))
+ die("bounds", regs, error_code);
+
+ if (!cpu_feature_enabled(X86_FEATURE_MPX)) {
+ /* The exception is not from Intel MPX */
+ goto exit_trap;
+ }
+
+ /*
+ * We need to look at BNDSTATUS to resolve this exception.
+ * It is not directly accessible, though, so we need to
+ * do an xsave and then pull it out of the xsave buffer.
+ */
+ fpu_save_init(&tsk->thread.fpu);
+ xsave_buf = &(tsk->thread.fpu.state->xsave);
+ bndcsr = get_xsave_addr(xsave_buf, XSTATE_BNDCSR);
+ if (!bndcsr)
+ goto exit_trap;
+
+ /*
+ * The error code field of the BNDSTATUS register communicates status
+ * information of a bound range exception #BR or operation involving
+ * bound directory.
+ */
+ switch (bndcsr->bndstatus & MPX_BNDSTA_ERROR_CODE) {
+ case 2: /* Bound directory has invalid entry. */
+ if (mpx_handle_bd_fault(xsave_buf))
+ goto exit_trap;
+ break; /* Success, it was handled */
+ case 1: /* Bound violation. */
+ info = mpx_generate_siginfo(regs, xsave_buf);
+ if (PTR_ERR(info)) {
+ /*
+ * We failed to decode the MPX instruction. Act as if
+ * the exception was not caused by MPX.
+ */
+ goto exit_trap;
+ }
+ /*
+ * Success, we decoded the instruction and retrieved
+ * an 'info' containing the address being accessed
+ * which caused the exception. This information
+ * allows and application to possibly handle the
+ * #BR exception itself.
+ */
+ do_trap(X86_TRAP_BR, SIGSEGV, "bounds", regs, error_code, info);
+ kfree(info);
+ break;
+ case 0: /* No exception caused by Intel MPX operations. */
+ goto exit_trap;
+ default:
+ die("bounds", regs, error_code);
+ }
+
+exit:
+ exception_exit(prev_state);
+ return;
+exit_trap:
+ /*
+ * This path out is for all the cases where we could not
+ * handle the exception in some way (like allocating a
+ * table or telling userspace about it. We will also end
+ * up here if the kernel has MPX turned off at compile
+ * time..
+ */
+ do_trap(X86_TRAP_BR, SIGSEGV, "bounds", regs, error_code, NULL);
+ exception_exit(prev_state);
+}
+
dotraplinkage void
do_general_protection(struct pt_regs *regs, long error_code)
{
diff --git a/arch/x86/mm/mpx.c b/arch/x86/mm/mpx.c
index 9009e094d686..96266375441e 100644
--- a/arch/x86/mm/mpx.c
+++ b/arch/x86/mm/mpx.c
@@ -10,8 +10,12 @@
#include <linux/syscalls.h>
#include <linux/sched/sysctl.h>
+#include <asm/i387.h>
+#include <asm/insn.h>
#include <asm/mman.h>
#include <asm/mpx.h>
+#include <asm/processor.h>
+#include <asm/fpu-internal.h>
static const char *mpx_mapping_name(struct vm_area_struct *vma)
{
@@ -266,10 +270,11 @@ bad_opcode:
siginfo_t *mpx_generate_siginfo(struct pt_regs *regs,
struct xsave_struct *xsave_buf)
{
+ struct bndreg *bndregs, *bndreg;
+ siginfo_t *info = NULL;
struct insn insn;
uint8_t bndregno;
int err;
- siginfo_t *info;
err = mpx_insn_decode(&insn, regs);
if (err)
@@ -285,6 +290,15 @@ siginfo_t *mpx_generate_siginfo(struct pt_regs *regs,
err = -EINVAL;
goto err_out;
}
+ /* get the bndregs _area_ of the xsave structure */
+ bndregs = get_xsave_addr(xsave_buf, XSTATE_BNDREGS);
+ if (!bndregs) {
+ err = -EINVAL;
+ goto err_out;
+ }
+ /* now go select the individual register in the set of 4 */
+ bndreg = &bndregs[bndregno];
+
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info) {
err = -ENOMEM;
@@ -300,10 +314,8 @@ siginfo_t *mpx_generate_siginfo(struct pt_regs *regs,
* complains when casting from integers to different-size
* pointers.
*/
- info->si_lower = (void __user *)(unsigned long)
- (xsave_buf->bndreg[bndregno].lower_bound);
- info->si_upper = (void __user *)(unsigned long)
- (~xsave_buf->bndreg[bndregno].upper_bound);
+ info->si_lower = (void __user *)(unsigned long)bndreg->lower_bound;
+ info->si_upper = (void __user *)(unsigned long)~bndreg->upper_bound;
info->si_addr_lsb = 0;
info->si_signo = SIGSEGV;
info->si_errno = 0;
@@ -319,5 +331,206 @@ siginfo_t *mpx_generate_siginfo(struct pt_regs *regs,
}
return info;
err_out:
+ /* info might be NULL, but kfree() handles that */
+ kfree(info);
return ERR_PTR(err);
}
+
+static __user void *task_get_bounds_dir(struct task_struct *tsk)
+{
+ struct bndcsr *bndcsr;
+
+ if (!cpu_feature_enabled(X86_FEATURE_MPX))
+ return MPX_INVALID_BOUNDS_DIR;
+
+ /*
+ * The bounds directory pointer is stored in a register
+ * only accessible if we first do an xsave.
+ */
+ fpu_save_init(&tsk->thread.fpu);
+ bndcsr = get_xsave_addr(&tsk->thread.fpu.state->xsave, XSTATE_BNDCSR);
+ if (!bndcsr)
+ return MPX_INVALID_BOUNDS_DIR;
+
+ /*
+ * Make sure the register looks valid by checking the
+ * enable bit.
+ */
+ if (!(bndcsr->bndcfgu & MPX_BNDCFG_ENABLE_FLAG))
+ return MPX_INVALID_BOUNDS_DIR;
+
+ /*
+ * Lastly, mask off the low bits used for configuration
+ * flags, and return the address of the bounds table.
+ */
+ return (void __user *)(unsigned long)
+ (bndcsr->bndcfgu & MPX_BNDCFG_ADDR_MASK);
+}
+
+int mpx_enable_management(struct task_struct *tsk)
+{
+ void __user *bd_base = MPX_INVALID_BOUNDS_DIR;
+ struct mm_struct *mm = tsk->mm;
+ int ret = 0;
+
+ /*
+ * runtime in the userspace will be responsible for allocation of
+ * the bounds directory. Then, it will save the base of the bounds
+ * directory into XSAVE/XRSTOR Save Area and enable MPX through
+ * XRSTOR instruction.
+ *
+ * fpu_xsave() is expected to be very expensive. Storing the bounds
+ * directory here means that we do not have to do xsave in the unmap
+ * path; we can just use mm->bd_addr instead.
+ */
+ bd_base = task_get_bounds_dir(tsk);
+ down_write(&mm->mmap_sem);
+ mm->bd_addr = bd_base;
+ if (mm->bd_addr == MPX_INVALID_BOUNDS_DIR)
+ ret = -ENXIO;
+
+ up_write(&mm->mmap_sem);
+ return ret;
+}
+
+int mpx_disable_management(struct task_struct *tsk)
+{
+ struct mm_struct *mm = current->mm;
+
+ if (!cpu_feature_enabled(X86_FEATURE_MPX))
+ return -ENXIO;
+
+ down_write(&mm->mmap_sem);
+ mm->bd_addr = MPX_INVALID_BOUNDS_DIR;
+ up_write(&mm->mmap_sem);
+ return 0;
+}
+
+/*
+ * With 32-bit mode, MPX_BT_SIZE_BYTES is 4MB, and the size of each
+ * bounds table is 16KB. With 64-bit mode, MPX_BT_SIZE_BYTES is 2GB,
+ * and the size of each bounds table is 4MB.
+ */
+static int allocate_bt(long __user *bd_entry)
+{
+ unsigned long expected_old_val = 0;
+ unsigned long actual_old_val = 0;
+ unsigned long bt_addr;
+ int ret = 0;
+
+ /*
+ * Carve the virtual space out of userspace for the new
+ * bounds table:
+ */
+ bt_addr = mpx_mmap(MPX_BT_SIZE_BYTES);
+ if (IS_ERR((void *)bt_addr))
+ return PTR_ERR((void *)bt_addr);
+ /*
+ * Set the valid flag (kinda like _PAGE_PRESENT in a pte)
+ */
+ bt_addr = bt_addr | MPX_BD_ENTRY_VALID_FLAG;
+
+ /*
+ * Go poke the address of the new bounds table in to the
+ * bounds directory entry out in userspace memory. Note:
+ * we may race with another CPU instantiating the same table.
+ * In that case the cmpxchg will see an unexpected
+ * 'actual_old_val'.
+ *
+ * This can fault, but that's OK because we do not hold
+ * mmap_sem at this point, unlike some of the other part
+ * of the MPX code that have to pagefault_disable().
+ */
+ ret = user_atomic_cmpxchg_inatomic(&actual_old_val, bd_entry,
+ expected_old_val, bt_addr);
+ if (ret)
+ goto out_unmap;
+
+ /*
+ * The user_atomic_cmpxchg_inatomic() will only return nonzero
+ * for faults, *not* if the cmpxchg itself fails. Now we must
+ * verify that the cmpxchg itself completed successfully.
+ */
+ /*
+ * We expected an empty 'expected_old_val', but instead found
+ * an apparently valid entry. Assume we raced with another
+ * thread to instantiate this table and desclare succecss.
+ */
+ if (actual_old_val & MPX_BD_ENTRY_VALID_FLAG) {
+ ret = 0;
+ goto out_unmap;
+ }
+ /*
+ * We found a non-empty bd_entry but it did not have the
+ * VALID_FLAG set. Return an error which will result in
+ * a SEGV since this probably means that somebody scribbled
+ * some invalid data in to a bounds table.
+ */
+ if (expected_old_val != actual_old_val) {
+ ret = -EINVAL;
+ goto out_unmap;
+ }
+ return 0;
+out_unmap:
+ vm_munmap(bt_addr & MPX_BT_ADDR_MASK, MPX_BT_SIZE_BYTES);
+ return ret;
+}
+
+/*
+ * When a BNDSTX instruction attempts to save bounds to a bounds
+ * table, it will first attempt to look up the table in the
+ * first-level bounds directory. If it does not find a table in
+ * the directory, a #BR is generated and we get here in order to
+ * allocate a new table.
+ *
+ * With 32-bit mode, the size of BD is 4MB, and the size of each
+ * bound table is 16KB. With 64-bit mode, the size of BD is 2GB,
+ * and the size of each bound table is 4MB.
+ */
+static int do_mpx_bt_fault(struct xsave_struct *xsave_buf)
+{
+ unsigned long bd_entry, bd_base;
+ struct bndcsr *bndcsr;
+
+ bndcsr = get_xsave_addr(xsave_buf, XSTATE_BNDCSR);
+ if (!bndcsr)
+ return -EINVAL;
+ /*
+ * Mask off the preserve and enable bits
+ */
+ bd_base = bndcsr->bndcfgu & MPX_BNDCFG_ADDR_MASK;
+ /*
+ * The hardware provides the address of the missing or invalid
+ * entry via BNDSTATUS, so we don't have to go look it up.
+ */
+ bd_entry = bndcsr->bndstatus & MPX_BNDSTA_ADDR_MASK;
+ /*
+ * Make sure the directory entry is within where we think
+ * the directory is.
+ */
+ if ((bd_entry < bd_base) ||
+ (bd_entry >= bd_base + MPX_BD_SIZE_BYTES))
+ return -EINVAL;
+
+ return allocate_bt((long __user *)bd_entry);
+}
+
+int mpx_handle_bd_fault(struct xsave_struct *xsave_buf)
+{
+ /*
+ * Userspace never asked us to manage the bounds tables,
+ * so refuse to help.
+ */
+ if (!kernel_managing_mpx_tables(current->mm))
+ return -EINVAL;
+
+ if (do_mpx_bt_fault(xsave_buf)) {
+ force_sig(SIGSEGV, current);
+ /*
+ * The force_sig() is essentially "handling" this
+ * exception, so we do not pass up the error
+ * from do_mpx_bt_fault().
+ */
+ }
+ return 0;
+}
diff --git a/fs/exec.c b/fs/exec.c
index 7302b75a9820..65d4f5c70ef4 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -60,6 +60,7 @@
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
#include <asm/tlb.h>
+#include <asm/mpx.h>
#include <trace/events/task.h>
#include "internal.h"
@@ -277,6 +278,7 @@ static int __bprm_mm_init(struct linux_binprm *bprm)
goto err;
mm->stack_vm = mm->total_vm = 1;
+ arch_bprm_mm_init(mm, vma);
up_write(&mm->mmap_sem);
bprm->p = vma->vm_end - sizeof(void *);
return 0;
diff --git a/include/asm-generic/mmu_context.h b/include/asm-generic/mmu_context.h
index a7eec910ba6c..1f2a8f9c9264 100644
--- a/include/asm-generic/mmu_context.h
+++ b/include/asm-generic/mmu_context.h
@@ -42,4 +42,9 @@ static inline void activate_mm(struct mm_struct *prev_mm,
{
}
+static inline void arch_bprm_mm_init(struct mm_struct *mm,
+ struct vm_area_struct *vma)
+{
+}
+
#endif /* __ASM_GENERIC_MMU_CONTEXT_H */
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 6e0b286649f1..004e9d17b47e 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -454,6 +454,10 @@ struct mm_struct {
bool tlb_flush_pending;
#endif
struct uprobes_state uprobes_state;
+#ifdef CONFIG_X86_INTEL_MPX
+ /* address of the bounds directory */
+ void __user *bd_addr;
+#endif
};
static inline void mm_init_cpumask(struct mm_struct *mm)
diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h
index 513df75d0fc9..89f63503f903 100644
--- a/include/uapi/linux/prctl.h
+++ b/include/uapi/linux/prctl.h
@@ -179,4 +179,10 @@ struct prctl_mm_map {
#define PR_SET_THP_DISABLE 41
#define PR_GET_THP_DISABLE 42
+/*
+ * Tell the kernel to start/stop helping userspace manage bounds tables.
+ */
+#define PR_MPX_ENABLE_MANAGEMENT 43
+#define PR_MPX_DISABLE_MANAGEMENT 44
+
#endif /* _LINUX_PRCTL_H */
diff --git a/kernel/sys.c b/kernel/sys.c
index 1eaa2f0b0246..a8c9f5a7dda6 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -91,6 +91,12 @@
#ifndef SET_TSC_CTL
# define SET_TSC_CTL(a) (-EINVAL)
#endif
+#ifndef MPX_ENABLE_MANAGEMENT
+# define MPX_ENABLE_MANAGEMENT(a) (-EINVAL)
+#endif
+#ifndef MPX_DISABLE_MANAGEMENT
+# define MPX_DISABLE_MANAGEMENT(a) (-EINVAL)
+#endif
/*
* this is where the system-wide overflow UID and GID are defined, for
@@ -2203,6 +2209,12 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
me->mm->def_flags &= ~VM_NOHUGEPAGE;
up_write(&me->mm->mmap_sem);
break;
+ case PR_MPX_ENABLE_MANAGEMENT:
+ error = MPX_ENABLE_MANAGEMENT(me);
+ break;
+ case PR_MPX_DISABLE_MANAGEMENT:
+ error = MPX_DISABLE_MANAGEMENT(me);
+ break;
default:
error = -EINVAL;
break;