include/linux/nospec.h

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

File Facts

System
Linux kernel
Corpus path
include/linux/nospec.h
Extension
.h
Size
2290 bytes
Lines
75
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

*     if (index < size) {
 *         index = array_index_nospec(index, size);
 *         val = array[index];
 *     }
 *
 * ...if the CPU speculates past the bounds check then
 * array_index_nospec() will clamp the index within the range of [0,
 * size).
 */
#define array_index_nospec(index, size)					\
({									\
	typeof(index) _i = (index);					\
	typeof(size) _s = (size);					\
	unsigned long _mask = array_index_mask_nospec(_i, _s);		\
									\
	BUILD_BUG_ON(sizeof(_i) > sizeof(long));			\
	BUILD_BUG_ON(sizeof(_s) > sizeof(long));			\
									\
	(typeof(_i)) (_i & _mask);					\
})

/* Speculation control prctl */
int arch_prctl_spec_ctrl_get(struct task_struct *task, unsigned long which);
int arch_prctl_spec_ctrl_set(struct task_struct *task, unsigned long which,
			     unsigned long ctrl);
/* Speculation control for seccomp enforced mitigation */
void arch_seccomp_spec_mitigate(struct task_struct *task);

#endif /* _LINUX_NOSPEC_H */

Annotation

Implementation Notes