1 files changed, 18 insertions, 13 deletions

diff --git a/arch/i386/kernel/cpu/mtrr/if.c b/arch/i386/kernel/cpu/mtrr/if.c
index 5ac051bb9d55..5ae1705eafa6 100644
--- a/arch/i386/kernel/cpu/mtrr/if.c
+++ b/arch/i386/kernel/cpu/mtrr/if.c
@@ -17,7 +17,7 @@ extern unsigned int *usage_table;
 
 #define FILE_FCOUNT(f) (((struct seq_file *)((f)->private_data))->private)
 
-static char *mtrr_strings[MTRR_NUM_TYPES] =
+static const char *const mtrr_strings[MTRR_NUM_TYPES] =
 {
     "uncachable",               /* 0 */
     "write-combining",          /* 1 */
@@ -28,7 +28,7 @@ static char *mtrr_strings[MTRR_NUM_TYPES] =
     "write-back",               /* 6 */
 };
 
-char *mtrr_attrib_to_str(int x)
+const char *mtrr_attrib_to_str(int x)
 {
         return (x <= 6) ? mtrr_strings[x] : "?";
 }
@@ -44,10 +44,9 @@ mtrr_file_add(unsigned long base, unsigned long size,
 
         max = num_var_ranges;
         if (fcount == NULL) {
-                fcount = kmalloc(max * sizeof *fcount, GFP_KERNEL);
+                fcount = kzalloc(max * sizeof *fcount, GFP_KERNEL);
                 if (!fcount)
                         return -ENOMEM;
-                memset(fcount, 0, max * sizeof *fcount);
                 FILE_FCOUNT(file) = fcount;
         }
         if (!page) {
@@ -155,6 +154,7 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
 {
         int err = 0;
         mtrr_type type;
+        unsigned long size;
         struct mtrr_sentry sentry;
         struct mtrr_gentry gentry;
         void __user *arg = (void __user *) __arg;
@@ -235,15 +235,15 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
         case MTRRIOC_GET_ENTRY:
                 if (gentry.regnum >= num_var_ranges)
                         return -EINVAL;
-                mtrr_if->get(gentry.regnum, &gentry.base, &gentry.size, &type);
+                mtrr_if->get(gentry.regnum, &gentry.base, &size, &type);
 
                 /* Hide entries that go above 4GB */
-                if (gentry.base + gentry.size > 0x100000
-                    || gentry.size == 0x100000)
+                if (gentry.base + size - 1 >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT))
+                    || size >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT)))
                         gentry.base = gentry.size = gentry.type = 0;
                 else {
                         gentry.base <<= PAGE_SHIFT;
-                        gentry.size <<= PAGE_SHIFT;
+                        gentry.size = size << PAGE_SHIFT;
                         gentry.type = type;
                 }
 
@@ -273,8 +273,14 @@ mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
         case MTRRIOC_GET_PAGE_ENTRY:
                 if (gentry.regnum >= num_var_ranges)
                         return -EINVAL;
-                mtrr_if->get(gentry.regnum, &gentry.base, &gentry.size, &type);
-                gentry.type = type;
+                mtrr_if->get(gentry.regnum, &gentry.base, &size, &type);
+                /* Hide entries that would overflow */
+                if (size != (__typeof__(gentry.size))size)
+                        gentry.base = gentry.size = gentry.type = 0;
+                else {
+                        gentry.size = size;
+                        gentry.type = type;
+                }
                 break;
         }
 
@@ -353,8 +359,7 @@ static int mtrr_seq_show(struct seq_file *seq, void *offset)
         char factor;
         int i, max, len;
         mtrr_type type;
-        unsigned long base;
-        unsigned int size;
+        unsigned long base, size;
 
         len = 0;
         max = num_var_ranges;
@@ -373,7 +378,7 @@ static int mtrr_seq_show(struct seq_file *seq, void *offset)
                         }
                         /* RED-PEN: base can be > 32bit */ 
                         len += seq_printf(seq, 
-                                   "reg%02i: base=0x%05lx000 (%4liMB), size=%4i%cB: %s, count=%d\n",
+                                   "reg%02i: base=0x%05lx000 (%4luMB), size=%4lu%cB: %s, count=%d\n",
                              i, base, base >> (20 - PAGE_SHIFT), size, factor,
                              mtrr_attrib_to_str(type), usage_table[i]);
                 }