x86/ldt: Make all size computations unsigned

ldt->size can never be negative. The helper functions take 'unsigned int'
arguments which are assigned from ldt->size. The related user space
user_desc struct member entry_number is unsigned as well.

But ldt->size itself and a few local variables which are related to
ldt->size are type 'int' which makes no sense whatsoever and results in
typecasts which make the eyes bleed.

Clean it up and convert everything which is related to ldt->size to
unsigned it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>

3 files changed, 7 insertions, 7 deletions

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 6e395c996900..55e6c8a397c2 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -2299,7 +2299,7 @@ valid_user_frame(const void __user *fp, unsigned long size)
 static unsigned long get_segment_base(unsigned int segment)
 {
         struct desc_struct *desc;
-        int idx = segment >> 3;
+        unsigned int idx = segment >> 3;
 
         if ((segment & SEGMENT_TI_MASK) == SEGMENT_LDT) {
 #ifdef CONFIG_MODIFY_LDT_SYSCALL
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index 8e0a9fe86de4..306c7e12af55 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -47,7 +47,7 @@ struct ldt_struct {
          * allocations, but it's not worth trying to optimize.
          */
         struct desc_struct *entries;
-        int size;
+        unsigned int size;
 };
 
 /*
diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c
index e25b6681cc65..f09df2ff1bcc 100644
--- a/arch/x86/kernel/ldt.c
+++ b/arch/x86/kernel/ldt.c
@@ -37,7 +37,7 @@ static void flush_ldt(void *current_mm)
 static struct ldt_struct *alloc_ldt_struct(unsigned int size)
 {
         struct ldt_struct *new_ldt;
-        int alloc_size;
+        unsigned int alloc_size;
 
         if (size > LDT_ENTRIES)
                 return NULL;
@@ -207,11 +207,11 @@ static int read_default_ldt(void __user *ptr, unsigned long bytecount)
 static int write_ldt(void __user *ptr, unsigned long bytecount, int oldmode)
 {
         struct mm_struct *mm = current->mm;
+        struct ldt_struct *new_ldt, *old_ldt;
+        unsigned int oldsize, newsize;
+        struct user_desc ldt_info;
         struct desc_struct ldt;
         int error;
-        struct user_desc ldt_info;
-        int oldsize, newsize;
-        struct ldt_struct *new_ldt, *old_ldt;
 
         error = -EINVAL;
         if (bytecount != sizeof(ldt_info))
@@ -249,7 +249,7 @@ static int write_ldt(void __user *ptr, unsigned long bytecount, int oldmode)
 
         old_ldt = mm->context.ldt;
         oldsize = old_ldt ? old_ldt->size : 0;
-        newsize = max((int)(ldt_info.entry_number + 1), oldsize);
+        newsize = max(ldt_info.entry_number + 1, oldsize);
 
         error = -ENOMEM;
         new_ldt = alloc_ldt_struct(newsize);