cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

bpfptr.h (1891B)

      1/* SPDX-License-Identifier: GPL-2.0-only */
      2/* A pointer that can point to either kernel or userspace memory. */
      3#ifndef _LINUX_BPFPTR_H
      4#define _LINUX_BPFPTR_H
      5
      6#include <linux/mm.h>
      7#include <linux/sockptr.h>
      8
      9typedef sockptr_t bpfptr_t;
     10
     11static inline bool bpfptr_is_kernel(bpfptr_t bpfptr)
     12{
     13	return bpfptr.is_kernel;
     14}
     15
     16static inline bpfptr_t KERNEL_BPFPTR(void *p)
     17{
     18	return (bpfptr_t) { .kernel = p, .is_kernel = true };
     19}
     20
     21static inline bpfptr_t USER_BPFPTR(void __user *p)
     22{
     23	return (bpfptr_t) { .user = p };
     24}
     25
     26static inline bpfptr_t make_bpfptr(u64 addr, bool is_kernel)
     27{
     28	if (is_kernel)
     29		return KERNEL_BPFPTR((void*) (uintptr_t) addr);
     30	else
     31		return USER_BPFPTR(u64_to_user_ptr(addr));
     32}
     33
     34static inline bool bpfptr_is_null(bpfptr_t bpfptr)
     35{
     36	if (bpfptr_is_kernel(bpfptr))
     37		return !bpfptr.kernel;
     38	return !bpfptr.user;
     39}
     40
     41static inline void bpfptr_add(bpfptr_t *bpfptr, size_t val)
     42{
     43	if (bpfptr_is_kernel(*bpfptr))
     44		bpfptr->kernel += val;
     45	else
     46		bpfptr->user += val;
     47}
     48
     49static inline int copy_from_bpfptr_offset(void *dst, bpfptr_t src,
     50					  size_t offset, size_t size)
     51{
     52	return copy_from_sockptr_offset(dst, (sockptr_t) src, offset, size);
     53}
     54
     55static inline int copy_from_bpfptr(void *dst, bpfptr_t src, size_t size)
     56{
     57	return copy_from_bpfptr_offset(dst, src, 0, size);
     58}
     59
     60static inline int copy_to_bpfptr_offset(bpfptr_t dst, size_t offset,
     61					const void *src, size_t size)
     62{
     63	return copy_to_sockptr_offset((sockptr_t) dst, offset, src, size);
     64}
     65
     66static inline void *kvmemdup_bpfptr(bpfptr_t src, size_t len)
     67{
     68	void *p = kvmalloc(len, GFP_USER | __GFP_NOWARN);
     69
     70	if (!p)
     71		return ERR_PTR(-ENOMEM);
     72	if (copy_from_bpfptr(p, src, len)) {
     73		kvfree(p);
     74		return ERR_PTR(-EFAULT);
     75	}
     76	return p;
     77}
     78
     79static inline long strncpy_from_bpfptr(char *dst, bpfptr_t src, size_t count)
     80{
     81	return strncpy_from_sockptr(dst, (sockptr_t) src, count);
     82}
     83
     84#endif /* _LINUX_BPFPTR_H */