mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-31 08:28:13 +00:00
1fb85d06ad
Reduce code duplication by moving canonical address code to a common header file. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20220131072453.2839535-3-adrian.hunter@intel.com
24 lines
704 B
C
24 lines
704 B
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
|
|
#include <linux/uaccess.h>
|
|
#include <linux/kernel.h>
|
|
|
|
#ifdef CONFIG_X86_64
|
|
bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
|
|
{
|
|
unsigned long vaddr = (unsigned long)unsafe_src;
|
|
|
|
/*
|
|
* Range covering the highest possible canonical userspace address
|
|
* as well as non-canonical address range. For the canonical range
|
|
* we also need to include the userspace guard page.
|
|
*/
|
|
return vaddr >= TASK_SIZE_MAX + PAGE_SIZE &&
|
|
__is_canonical_address(vaddr, boot_cpu_data.x86_virt_bits);
|
|
}
|
|
#else
|
|
bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size)
|
|
{
|
|
return (unsigned long)unsafe_src >= TASK_SIZE_MAX;
|
|
}
|
|
#endif
|