Hey guys,
do you have anything against the below renaming?
ldt->size is simply confusing while it wants to be called ldt->n_entries
as it is used like this throughout the code.
Let me know before I go and run it to check I'm not breaking anything.
Thanks!
---
... because this is exactly what it is: the number of entries in the
LDT. Calling it "size" is simply confusing and it is actually begging to
be called "n_entries" or somesuch if you see constructs like:
alloc_size = size * LDT_ENTRY_SIZE;
since LDT_ENTRY_SIZE is the size of a single entry.
There should be no functionality change resulting from this patch.
Signed-off-by: Borislav Petkov <[email protected]>
---
arch/x86/events/core.c | 2 +-
arch/x86/include/asm/mmu_context.h | 4 ++--
arch/x86/kernel/ldt.c | 38 +++++++++++++++++++-------------------
arch/x86/kernel/process_64.c | 2 +-
arch/x86/kernel/step.c | 2 +-
5 files changed, 24 insertions(+), 24 deletions(-)
diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 637feed9a594..82c3083f53b3 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -2343,7 +2343,7 @@ static unsigned long get_segment_base(unsigned int
segment)
/* IRQs are off, so this synchronizes with smp_store_release */
ldt = lockless_dereference(current->active_mm->context.ldt);
- if (!ldt || idx > ldt->size)
+ if (!ldt || idx > ldt->n_entries)
return 0;
desc = &ldt->entries[idx];
diff --git a/arch/x86/include/asm/mmu_context.h
b/arch/x86/include/asm/mmu_context.h
index 68b329d77b3a..872e94933b9b 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;
- unsigned int size;
+ unsigned int n_entries;
};
/*
@@ -87,7 +87,7 @@ static inline void load_mm_ldt(struct mm_struct *mm)
*/
if (unlikely(ldt))
- set_ldt(ldt->entries, ldt->size);
+ set_ldt(ldt->entries, ldt->n_entries);
else
clear_LDT();
#else
diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c
index d4a15831ac58..da2184f3d100 100644
--- a/arch/x86/kernel/ldt.c
+++ b/arch/x86/kernel/ldt.c
@@ -30,16 +30,16 @@ static void flush_ldt(void *current_mm)
return;
pc = ¤t->active_mm->context;
- set_ldt(pc->ldt->entries, pc->ldt->size);
+ set_ldt(pc->ldt->entries, pc->ldt->n_entries);
}
/* The caller must call finalize_ldt_struct on the result. LDT starts zeroed.
*/
-static struct ldt_struct *alloc_ldt_struct(unsigned int size)
+static struct ldt_struct *alloc_ldt_struct(unsigned int num_entries)
{
struct ldt_struct *new_ldt;
unsigned int alloc_size;
- if (size > LDT_ENTRIES)
+ if (num_entries > LDT_ENTRIES)
return NULL;
new_ldt = kmalloc(sizeof(struct ldt_struct), GFP_KERNEL);
@@ -47,7 +47,7 @@ static struct ldt_struct *alloc_ldt_struct(unsigned int size)
return NULL;
BUILD_BUG_ON(LDT_ENTRY_SIZE != sizeof(struct desc_struct));
- alloc_size = size * LDT_ENTRY_SIZE;
+ alloc_size = num_entries * LDT_ENTRY_SIZE;
/*
* Xen is very picky: it requires a page-aligned LDT that has no
@@ -65,14 +65,14 @@ static struct ldt_struct *alloc_ldt_struct(unsigned int
size)
return NULL;
}
- new_ldt->size = size;
+ new_ldt->n_entries = num_entries;
return new_ldt;
}
/* After calling this, the LDT is immutable. */
static void finalize_ldt_struct(struct ldt_struct *ldt)
{
- paravirt_alloc_ldt(ldt->entries, ldt->size);
+ paravirt_alloc_ldt(ldt->entries, ldt->n_entries);
}
/* context.lock is held */
@@ -91,8 +91,8 @@ static void free_ldt_struct(struct ldt_struct *ldt)
if (likely(!ldt))
return;
- paravirt_free_ldt(ldt->entries, ldt->size);
- if (ldt->size * LDT_ENTRY_SIZE > PAGE_SIZE)
+ paravirt_free_ldt(ldt->entries, ldt->n_entries);
+ if (ldt->n_entries * LDT_ENTRY_SIZE > PAGE_SIZE)
vfree_atomic(ldt->entries);
else
free_page((unsigned long)ldt->entries);
@@ -122,14 +122,14 @@ int init_new_context_ldt(struct task_struct *tsk, struct
mm_struct *mm)
goto out_unlock;
}
- new_ldt = alloc_ldt_struct(old_mm->context.ldt->size);
+ new_ldt = alloc_ldt_struct(old_mm->context.ldt->n_entries);
if (!new_ldt) {
retval = -ENOMEM;
goto out_unlock;
}
memcpy(new_ldt->entries, old_mm->context.ldt->entries,
- new_ldt->size * LDT_ENTRY_SIZE);
+ new_ldt->n_entries * LDT_ENTRY_SIZE);
finalize_ldt_struct(new_ldt);
mm->context.ldt = new_ldt;
@@ -152,9 +152,9 @@ void destroy_context_ldt(struct mm_struct *mm)
static int read_ldt(void __user *ptr, unsigned long bytecount)
{
- int retval;
- unsigned long size;
struct mm_struct *mm = current->mm;
+ unsigned long num_entries;
+ int retval;
mutex_lock(&mm->context.lock);
@@ -166,18 +166,18 @@ static int read_ldt(void __user *ptr, unsigned long
bytecount)
if (bytecount > LDT_ENTRY_SIZE * LDT_ENTRIES)
bytecount = LDT_ENTRY_SIZE * LDT_ENTRIES;
- size = mm->context.ldt->size * LDT_ENTRY_SIZE;
- if (size > bytecount)
- size = bytecount;
+ num_entries = mm->context.ldt->n_entries * LDT_ENTRY_SIZE;
+ if (num_entries > bytecount)
+ num_entries = bytecount;
- if (copy_to_user(ptr, mm->context.ldt->entries, size)) {
+ if (copy_to_user(ptr, mm->context.ldt->entries, num_entries)) {
retval = -EFAULT;
goto out_unlock;
}
- if (size != bytecount) {
+ if (num_entries != bytecount) {
/* Zero-fill the rest and pretend we read bytecount bytes. */
- if (clear_user(ptr + size, bytecount - size)) {
+ if (clear_user(ptr + num_entries, bytecount - num_entries)) {
retval = -EFAULT;
goto out_unlock;
}
@@ -248,7 +248,7 @@ static int write_ldt(void __user *ptr, unsigned long
bytecount, int oldmode)
mutex_lock(&mm->context.lock);
old_ldt = mm->context.ldt;
- oldsize = old_ldt ? old_ldt->size : 0;
+ oldsize = old_ldt ? old_ldt->n_entries : 0;
newsize = max(ldt_info.entry_number + 1, oldsize);
error = -ENOMEM;
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index b6840bf3940b..95c76edc4587 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -142,7 +142,7 @@ void release_thread(struct task_struct *dead_task)
pr_warn("WARNING: dead process %s still has LDT?
<%p/%d>\n",
dead_task->comm,
dead_task->mm->context.ldt->entries,
- dead_task->mm->context.ldt->size);
+ dead_task->mm->context.ldt->n_entries);
BUG();
}
#endif
diff --git a/arch/x86/kernel/step.c b/arch/x86/kernel/step.c
index f07f83b3611b..59b8b9470ed6 100644
--- a/arch/x86/kernel/step.c
+++ b/arch/x86/kernel/step.c
@@ -34,7 +34,7 @@ unsigned long convert_ip_to_linear(struct task_struct *child,
struct pt_regs *re
mutex_lock(&child->mm->context.lock);
if (unlikely(!child->mm->context.ldt ||
- seg >= child->mm->context.ldt->size))
+ seg >= child->mm->context.ldt->n_entries))
addr = -1L; /* bogus selector, access would fault */
else {
desc = &child->mm->context.ldt->entries[seg];
--
2.13.0
--
Regards/Gruss,
Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
