include/linux/kmsan-checks.h

Source file repositories/reference/linux-study-clean/include/linux/kmsan-checks.h

File Facts

System
Linux kernel
Corpus path
include/linux/kmsan-checks.h
Extension
.h
Size
2930 bytes
Lines
99
Domain
Core OS
Bucket
Core Kernel Interface
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef _LINUX_KMSAN_CHECKS_H
#define _LINUX_KMSAN_CHECKS_H

#include <linux/types.h>

#ifdef CONFIG_KMSAN

/**
 * kmsan_poison_memory() - Mark the memory range as uninitialized.
 * @address: address to start with.
 * @size:    size of buffer to poison.
 * @flags:   GFP flags for allocations done by this function.
 *
 * Until other data is written to this range, KMSAN will treat it as
 * uninitialized. Error reports for this memory will reference the call site of
 * kmsan_poison_memory() as origin.
 */
void kmsan_poison_memory(const void *address, size_t size, gfp_t flags);

/**
 * kmsan_unpoison_memory() -  Mark the memory range as initialized.
 * @address: address to start with.
 * @size:    size of buffer to unpoison.
 *
 * Until other data is written to this range, KMSAN will treat it as
 * initialized.
 */
void kmsan_unpoison_memory(const void *address, size_t size);

/**
 * kmsan_check_memory() - Check the memory range for being initialized.
 * @address: address to start with.
 * @size:    size of buffer to check.
 *
 * If any piece of the given range is marked as uninitialized, KMSAN will report
 * an error.
 */
void kmsan_check_memory(const void *address, size_t size);

/**
 * kmsan_copy_to_user() - Notify KMSAN about a data transfer to userspace.
 * @to:      destination address in the userspace.
 * @from:    source address in the kernel.
 * @to_copy: number of bytes to copy.
 * @left:    number of bytes not copied.
 *
 * If this is a real userspace data transfer, KMSAN checks the bytes that were
 * actually copied to ensure there was no information leak. If @to belongs to
 * the kernel space (which is possible for compat syscalls), KMSAN just copies
 * the metadata.
 */
void kmsan_copy_to_user(void __user *to, const void *from, size_t to_copy,
			size_t left);

/**
 * kmsan_memmove() - Notify KMSAN about a data copy within kernel.
 * @to:   destination address in the kernel.
 * @from: source address in the kernel.
 * @size: number of bytes to copy.
 *
 * Invoked after non-instrumented version (e.g. implemented using assembly
 * code) of memmove()/memcpy() is called, in order to copy KMSAN's metadata.
 */
void kmsan_memmove(void *to, const void *from, size_t to_copy);

#else

static inline void kmsan_poison_memory(const void *address, size_t size,
				       gfp_t flags)
{
}
static inline void kmsan_unpoison_memory(const void *address, size_t size)
{
}
static inline void kmsan_check_memory(const void *address, size_t size)
{
}
static inline void kmsan_copy_to_user(void __user *to, const void *from,
				      size_t to_copy, size_t left)
{
}

static inline void kmsan_memmove(void *to, const void *from, size_t to_copy)
{
}

#endif

#endif /* _LINUX_KMSAN_CHECKS_H */

Annotation

Implementation Notes