domctl: Fix cpumap/cpumask conversion functions to return an error code.

Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
xen-unstable changeset:   21350:e50afc6ecc48
xen-unstable date:        Wed May 12 08:42:30 2010 +0100

4 files changed, 24 insertions, 20 deletions

diff --git a/xen/arch/x86/platform_hypercall.c b/xen/arch/x86/platform_hypercall.c
index dc2214930a..e7f3283c15 100644
--- a/xen/arch/x86/platform_hypercall.c
+++ b/xen/arch/x86/platform_hypercall.c
@@ -340,7 +340,8 @@ ret_t do_platform_op(XEN_GUEST_HANDLE(xen_platform_op_t) u_xenpf_op)
         guest_from_compat_handle(cpumap_bitmap,
                                  op->u.getidletime.cpumap_bitmap);
         ctlmap.bitmap.p = cpumap_bitmap.p; /* handle -> handle_64 conversion */
-        xenctl_cpumap_to_cpumask(&cpumap, &ctlmap);
+        if ( (ret = xenctl_cpumap_to_cpumask(&cpumap, &ctlmap)) != 0 )
+            goto out;
         guest_from_compat_handle(idletimes, op->u.getidletime.idletime);
 
         for_each_cpu_mask ( cpu, cpumap )
@@ -355,7 +356,9 @@ ret_t do_platform_op(XEN_GUEST_HANDLE(xen_platform_op_t) u_xenpf_op)
         }
 
         op->u.getidletime.now = now;
-        cpumask_to_xenctl_cpumap(&ctlmap, &cpumap);
+        if ( (ret = cpumask_to_xenctl_cpumap(&ctlmap, &cpumap)) != 0 )
+            goto out;
+
         ret = copy_to_guest(u_xenpf_op, op, 1) ? -EFAULT : 0;
     }
     break;
diff --git a/xen/common/domctl.c b/xen/common/domctl.c
index f87d91c06b..8819f2b449 100644
--- a/xen/common/domctl.c
+++ b/xen/common/domctl.c
@@ -30,37 +30,35 @@ static DEFINE_SPINLOCK(domctl_lock);
 extern long arch_do_domctl(
     struct xen_domctl *op, XEN_GUEST_HANDLE(xen_domctl_t) u_domctl);
 
-void cpumask_to_xenctl_cpumap(
+int cpumask_to_xenctl_cpumap(
     struct xenctl_cpumap *xenctl_cpumap, cpumask_t *cpumask)
 {
     unsigned int guest_bytes, copy_bytes, i;
     uint8_t zero = 0;
     uint8_t bytemap[(NR_CPUS + 7) / 8];
 
-    if ( guest_handle_is_null(xenctl_cpumap->bitmap) )
-        return;
-
     guest_bytes = (xenctl_cpumap->nr_cpus + 7) / 8;
     copy_bytes  = min_t(unsigned int, guest_bytes, sizeof(bytemap));
 
     bitmap_long_to_byte(bytemap, cpus_addr(*cpumask), NR_CPUS);
 
     if ( copy_bytes != 0 )
-        copy_to_guest(xenctl_cpumap->bitmap, bytemap, copy_bytes);
+        if ( copy_to_guest(xenctl_cpumap->bitmap, bytemap, copy_bytes) )
+            return -EFAULT;
 
     for ( i = copy_bytes; i < guest_bytes; i++ )
-        copy_to_guest_offset(xenctl_cpumap->bitmap, i, &zero, 1);
+        if ( copy_to_guest_offset(xenctl_cpumap->bitmap, i, &zero, 1) )
+            return -EFAULT;
+
+    return 0;
 }
 
-void xenctl_cpumap_to_cpumask(
+int xenctl_cpumap_to_cpumask(
     cpumask_t *cpumask, struct xenctl_cpumap *xenctl_cpumap)
 {
     unsigned int guest_bytes, copy_bytes;
     uint8_t bytemap[(NR_CPUS + 7) / 8];
 
-    if ( guest_handle_is_null(xenctl_cpumap->bitmap) )
-        return;
-
     guest_bytes = (xenctl_cpumap->nr_cpus + 7) / 8;
     copy_bytes  = min_t(unsigned int, guest_bytes, sizeof(bytemap));
 
@@ -68,12 +66,15 @@ void xenctl_cpumap_to_cpumask(
 
     if ( copy_bytes != 0 )
     {
-        copy_from_guest(bytemap, xenctl_cpumap->bitmap, copy_bytes);
+        if ( copy_from_guest(bytemap, xenctl_cpumap->bitmap, copy_bytes) )
+            return -EFAULT;
         if ( (xenctl_cpumap->nr_cpus & 7) && (guest_bytes <= sizeof(bytemap)) )
             bytemap[guest_bytes-1] &= ~(0xff << (xenctl_cpumap->nr_cpus & 7));
     }
 
     bitmap_byte_to_long(cpus_addr(*cpumask), bytemap, NR_CPUS);
+
+    return 0;
 }
 
 static inline int is_free_domid(domid_t dom)
@@ -574,15 +575,15 @@ long do_domctl(XEN_GUEST_HANDLE(xen_domctl_t) u_domctl)
 
         if ( op->cmd == XEN_DOMCTL_setvcpuaffinity )
         {
-            xenctl_cpumap_to_cpumask(
+            ret = xenctl_cpumap_to_cpumask(
                 &new_affinity, &op->u.vcpuaffinity.cpumap);
-            ret = vcpu_set_affinity(v, &new_affinity);
+            if ( !ret )
+                ret = vcpu_set_affinity(v, &new_affinity);
         }
         else
         {
-            cpumask_to_xenctl_cpumap(
+            ret = cpumask_to_xenctl_cpumap(
                 &op->u.vcpuaffinity.cpumap, &v->cpu_affinity);
-            ret = 0;
         }
 
     vcpuaffinity_out:
diff --git a/xen/common/trace.c b/xen/common/trace.c
index 48c8d273e9..c4264f0d79 100644
--- a/xen/common/trace.c
+++ b/xen/common/trace.c
@@ -343,7 +343,7 @@ int tb_control(xen_sysctl_tbuf_op_t *tbc)
         tbc->size = T_INFO_PAGES * PAGE_SIZE;
         break;
     case XEN_SYSCTL_TBUFOP_set_cpu_mask:
-        xenctl_cpumap_to_cpumask(&tb_cpu_mask, &tbc->cpu_mask);
+        rc = xenctl_cpumap_to_cpumask(&tb_cpu_mask, &tbc->cpu_mask);
         break;
     case XEN_SYSCTL_TBUFOP_set_evt_mask:
         tb_event_mask = tbc->evt_mask;
diff --git a/xen/include/xen/cpumask.h b/xen/include/xen/cpumask.h
index a0b3e15374..5ab202be7b 100644
--- a/xen/include/xen/cpumask.h
+++ b/xen/include/xen/cpumask.h
@@ -424,9 +424,9 @@ extern cpumask_t cpu_present_map;
 
 /* Copy to/from cpumap provided by control tools. */
 struct xenctl_cpumap;
-void cpumask_to_xenctl_cpumap(
+int cpumask_to_xenctl_cpumap(
     struct xenctl_cpumap *enctl_cpumap, cpumask_t *cpumask);
-void xenctl_cpumap_to_cpumask(
+int xenctl_cpumap_to_cpumask(
     cpumask_t *cpumask, struct xenctl_cpumap *enctl_cpumap);
 
 #endif /* __XEN_CPUMASK_H */