Changeset 1479562 in mainline

Timestamp:

2010-11-15T23:02:23Z (13 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

74c57908

Parents:

dd567c6

Message:

Let copy_from/to_uspace() detect attempts to access the address space memory
hole on amd64.

Location:

kernel

Files:

• arch/amd64/include/mm/as.h (modified) (1 diff)
• generic/src/syscall/copy.c (modified) (4 diffs)

kernel/arch/amd64/include/mm/as.h

@@ -36 +36 @@
 #define KERN_amd64_AS_H_
 
+#define ADDRESS_SPACE_HOLE_START        0x0000800000000000ULL
+#define ADDRESS_SPACE_HOLE_END          0xffff7fffffffffffULL
+
 #define KERNEL_ADDRESS_SPACE_SHADOWED_ARCH  0
 
-#define KERNEL_ADDRESS_SPACE_START_ARCH  (unsigned long) 0xffff800000000000
-#define KERNEL_ADDRESS_SPACE_END_ARCH    (unsigned long) 0xffffffffffffffff
+#define KERNEL_ADDRESS_SPACE_START_ARCH 0xffff800000000000ULL
+#define KERNEL_ADDRESS_SPACE_END_ARCH   0xffffffffffffffffULL
 
-#define USER_ADDRESS_SPACE_START_ARCH    (unsigned long) 0x0000000000000000
-#define USER_ADDRESS_SPACE_END_ARCH      (unsigned long) 0x00007fffffffffff
+#define USER_ADDRESS_SPACE_START_ARCH   0x0000000000000000ULL
+#define USER_ADDRESS_SPACE_END_ARCH     0x00007fffffffffffULL
 
 #define USTACK_ADDRESS_ARCH  (USER_ADDRESS_SPACE_END_ARCH - (PAGE_SIZE - 1))

kernel/generic/src/syscall/copy.c

@@ -68 +68 @@
         if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
                 if (overlaps((uintptr_t) uspace_src, size,
-                        KERNEL_ADDRESS_SPACE_START, KERNEL_ADDRESS_SPACE_END-KERNEL_ADDRESS_SPACE_START)) {
+                        KERNEL_ADDRESS_SPACE_START,
+                        KERNEL_ADDRESS_SPACE_END - KERNEL_ADDRESS_SPACE_START)) {
                         /*
                          * The userspace source block conflicts with kernel address space.
@@ -75 +76 @@
                 }
         }
+
+#ifdef ADDRESS_SPACE_HOLE_START
+        /*
+         * Check whether the address is outside the address space hole.
+         */
+        if (overlaps((uintptr_t) uspace_src, size, ADDRESS_SPACE_HOLE_START,
+            ADDRESS_SPACE_HOLE_END - ADDRESS_SPACE_HOLE_START))
+                return EPERM;
+#endif
         
         ipl = interrupts_disable();
@@ -109 +119 @@
         if (!KERNEL_ADDRESS_SPACE_SHADOWED) {
                 if (overlaps((uintptr_t) uspace_dst, size,
-                        KERNEL_ADDRESS_SPACE_START, KERNEL_ADDRESS_SPACE_END-KERNEL_ADDRESS_SPACE_START)) {
+                        KERNEL_ADDRESS_SPACE_START,
+                        KERNEL_ADDRESS_SPACE_END - KERNEL_ADDRESS_SPACE_START)) {
                         /*
                          * The userspace destination block conflicts with kernel address space.
@@ -116 +127 @@
                 }
         }
+
+#ifdef ADDRESS_SPACE_HOLE_START
+        /*
+         * Check whether the address is outside the address space hole.
+         */
+        if (overlaps((uintptr_t) uspace_dst, size, ADDRESS_SPACE_HOLE_START,
+            ADDRESS_SPACE_HOLE_END - ADDRESS_SPACE_HOLE_START))
+                return EPERM;
+#endif
         
         ipl = interrupts_disable();