[PATCH 1/2] mm: rename copy_from_kernel_nofault_allowed() to copy_kernel_nofault_allowed()

Omar Sandoval
2024-09-02T05:35:12Z

From: Omar Sandoval <osandov@fb.com>

All of the existing checks are applicable to both the "from" and "to"
directions, and the next patch needs it for copy_to_kernel_nofault().

Signed-off-by: Omar Sandoval <osandov@fb.com>
---
arch/arm/mm/fault.c | 2 +-
arch/loongarch/mm/maccess.c | 2 +-
arch/mips/mm/maccess.c | 2 +-
arch/parisc/lib/memcpy.c | 2 +-
arch/powerpc/mm/maccess.c | 2 +-
arch/um/kernel/maccess.c | 2 +-
arch/x86/mm/maccess.c | 4 ++--
include/linux/uaccess.h | 2 +-
mm/maccess.c | 7 +++----
9 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index ab01b51de559..3fef0a59af4f 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -27,7 +27,7 @@

#ifdef CONFIG_MMU

-bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
+bool copy_kernel_nofault_allowed(const void *unsafe_src, size_t size)
{
unsigned long addr = (unsigned long)unsafe_src;

diff --git a/arch/loongarch/mm/maccess.c b/arch/loongarch/mm/maccess.c
index 58173842c6be..70012ac0a5a8 100644
--- a/arch/loongarch/mm/maccess.c
+++ b/arch/loongarch/mm/maccess.c
@@ -3,7 +3,7 @@
#include <linux/uaccess.h>
#include <linux/kernel.h>

-bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
+bool copy_kernel_nofault_allowed(const void *unsafe_src, size_t size)
{
/* highest bit set means kernel space */
return (unsigned long)unsafe_src >> (BITS_PER_LONG - 1);
diff --git a/arch/mips/mm/maccess.c b/arch/mips/mm/maccess.c
index 58173842c6be..70012ac0a5a8 100644
--- a/arch/mips/mm/maccess.c
+++ b/arch/mips/mm/maccess.c
@@ -3,7 +3,7 @@
#include <linux/uaccess.h>
#include <linux/kernel.h>

-bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
+bool copy_kernel_nofault_allowed(const void *unsafe_src, size_t size)
{
/* highest bit set means kernel space */
return (unsigned long)unsafe_src >> (BITS_PER_LONG - 1);
diff --git a/arch/parisc/lib/memcpy.c b/arch/parisc/lib/memcpy.c
index 5fc0c852c84c..78758b9a0f49 100644
--- a/arch/parisc/lib/memcpy.c
+++ b/arch/parisc/lib/memcpy.c
@@ -48,7 +48,7 @@ void * memcpy(void * dst,const void *src, size_t count)

EXPORT_SYMBOL(memcpy);

-bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
+bool copy_kernel_nofault_allowed(const void *unsafe_src, size_t size)
{
if ((unsigned long)unsafe_src < PAGE_SIZE)
return false;
diff --git a/arch/powerpc/mm/maccess.c b/arch/powerpc/mm/maccess.c
index ea821d0ffe16..e0f4c394836c 100644
--- a/arch/powerpc/mm/maccess.c
+++ b/arch/powerpc/mm/maccess.c
@@ -7,7 +7,7 @@
#include <asm/inst.h>
#include <asm/ppc-opcode.h>

-bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
+bool copy_kernel_nofault_allowed(const void *unsafe_src, size_t size)
{
return is_kernel_addr((unsigned long)unsafe_src);
}
diff --git a/arch/um/kernel/maccess.c b/arch/um/kernel/maccess.c
index 8ccd56813f68..3497148e9aa5 100644
--- a/arch/um/kernel/maccess.c
+++ b/arch/um/kernel/maccess.c
@@ -7,7 +7,7 @@
#include <linux/kernel.h>
#include <os.h>

-bool copy_from_kernel_nofault_allowed(const void *src, size_t size)
+bool copy_kernel_nofault_allowed(const void *src, size_t size)
{
void *psrc = (void *)rounddown((unsigned long)src, PAGE_SIZE);

diff --git a/arch/x86/mm/maccess.c b/arch/x86/mm/maccess.c
index 42115ac079cf..be28eda2c0b0 100644
--- a/arch/x86/mm/maccess.c
+++ b/arch/x86/mm/maccess.c
@@ -6,7 +6,7 @@
#include <asm/vsyscall.h>

#ifdef CONFIG_X86_64
-bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
+bool copy_kernel_nofault_allowed(const void *unsafe_src, size_t size)
{
unsigned long vaddr = (unsigned long)unsafe_src;

@@ -36,7 +36,7 @@ bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
return __is_canonical_address(vaddr, boot_cpu_data.x86_virt_bits);
}
#else
-bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
+bool copy_kernel_nofault_allowed(const void *unsafe_src, size_t size)
{
return (unsigned long)unsafe_src >= TASK_SIZE_MAX;
}
diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h
index d8e4105a2f21..297a02b2bd53 100644
--- a/include/linux/uaccess.h
+++ b/include/linux/uaccess.h
@@ -387,7 +387,7 @@ copy_struct_from_user(void *dst, size_t ksize, const void __user *src,
return 0;
}

-bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size);
+bool copy_kernel_nofault_allowed(const void *unsafe_src, size_t size);

long copy_from_kernel_nofault(void *dst, const void *src, size_t size);
long notrace copy_to_kernel_nofault(void *dst, const void *src, size_t size);
diff --git a/mm/maccess.c b/mm/maccess.c
index 518a25667323..72e9c03ea37f 100644
--- a/mm/maccess.c
+++ b/mm/maccess.c
@@ -7,8 +7,7 @@
#include <linux/uaccess.h>
#include <asm/tlb.h>

-bool __weak copy_from_kernel_nofault_allowed(const void *unsafe_src,
- size_t size)
+bool __weak copy_kernel_nofault_allowed(const void *unsafe_src, size_t size)
{
return true;
}
@@ -28,7 +27,7 @@ long copy_from_kernel_nofault(void *dst, const void *src, size_t size)
if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS))
align = (unsigned long)dst | (unsigned long)src;

- if (!copy_from_kernel_nofault_allowed(src, size))
+ if (!copy_kernel_nofault_allowed(src, size))
return -ERANGE;

pagefault_disable();
@@ -83,7 +82,7 @@ long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count)

if (unlikely(count <= 0))
return 0;
- if (!copy_from_kernel_nofault_allowed(unsafe_addr, count))
+ if (!copy_kernel_nofault_allowed(unsafe_addr, count))
return -ERANGE;

pagefault_disable();
--
2.46.0