162306a36Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0-only */ 262306a36Sopenharmony_ci/* A pointer that can point to either kernel or userspace memory. */ 362306a36Sopenharmony_ci#ifndef _LINUX_BPFPTR_H 462306a36Sopenharmony_ci#define _LINUX_BPFPTR_H 562306a36Sopenharmony_ci 662306a36Sopenharmony_ci#include <linux/mm.h> 762306a36Sopenharmony_ci#include <linux/sockptr.h> 862306a36Sopenharmony_ci 962306a36Sopenharmony_citypedef sockptr_t bpfptr_t; 1062306a36Sopenharmony_ci 1162306a36Sopenharmony_cistatic inline bool bpfptr_is_kernel(bpfptr_t bpfptr) 1262306a36Sopenharmony_ci{ 1362306a36Sopenharmony_ci return bpfptr.is_kernel; 1462306a36Sopenharmony_ci} 1562306a36Sopenharmony_ci 1662306a36Sopenharmony_cistatic inline bpfptr_t KERNEL_BPFPTR(void *p) 1762306a36Sopenharmony_ci{ 1862306a36Sopenharmony_ci return (bpfptr_t) { .kernel = p, .is_kernel = true }; 1962306a36Sopenharmony_ci} 2062306a36Sopenharmony_ci 2162306a36Sopenharmony_cistatic inline bpfptr_t USER_BPFPTR(void __user *p) 2262306a36Sopenharmony_ci{ 2362306a36Sopenharmony_ci return (bpfptr_t) { .user = p }; 2462306a36Sopenharmony_ci} 2562306a36Sopenharmony_ci 2662306a36Sopenharmony_cistatic inline bpfptr_t make_bpfptr(u64 addr, bool is_kernel) 2762306a36Sopenharmony_ci{ 2862306a36Sopenharmony_ci if (is_kernel) 2962306a36Sopenharmony_ci return KERNEL_BPFPTR((void*) (uintptr_t) addr); 3062306a36Sopenharmony_ci else 3162306a36Sopenharmony_ci return USER_BPFPTR(u64_to_user_ptr(addr)); 3262306a36Sopenharmony_ci} 3362306a36Sopenharmony_ci 3462306a36Sopenharmony_cistatic inline bool bpfptr_is_null(bpfptr_t bpfptr) 3562306a36Sopenharmony_ci{ 3662306a36Sopenharmony_ci if (bpfptr_is_kernel(bpfptr)) 3762306a36Sopenharmony_ci return !bpfptr.kernel; 3862306a36Sopenharmony_ci return !bpfptr.user; 3962306a36Sopenharmony_ci} 4062306a36Sopenharmony_ci 4162306a36Sopenharmony_cistatic inline void bpfptr_add(bpfptr_t *bpfptr, size_t val) 4262306a36Sopenharmony_ci{ 4362306a36Sopenharmony_ci if (bpfptr_is_kernel(*bpfptr)) 4462306a36Sopenharmony_ci bpfptr->kernel += val; 4562306a36Sopenharmony_ci else 4662306a36Sopenharmony_ci bpfptr->user += val; 4762306a36Sopenharmony_ci} 4862306a36Sopenharmony_ci 4962306a36Sopenharmony_cistatic inline int copy_from_bpfptr_offset(void *dst, bpfptr_t src, 5062306a36Sopenharmony_ci size_t offset, size_t size) 5162306a36Sopenharmony_ci{ 5262306a36Sopenharmony_ci if (!bpfptr_is_kernel(src)) 5362306a36Sopenharmony_ci return copy_from_user(dst, src.user + offset, size); 5462306a36Sopenharmony_ci return copy_from_kernel_nofault(dst, src.kernel + offset, size); 5562306a36Sopenharmony_ci} 5662306a36Sopenharmony_ci 5762306a36Sopenharmony_cistatic inline int copy_from_bpfptr(void *dst, bpfptr_t src, size_t size) 5862306a36Sopenharmony_ci{ 5962306a36Sopenharmony_ci return copy_from_bpfptr_offset(dst, src, 0, size); 6062306a36Sopenharmony_ci} 6162306a36Sopenharmony_ci 6262306a36Sopenharmony_cistatic inline int copy_to_bpfptr_offset(bpfptr_t dst, size_t offset, 6362306a36Sopenharmony_ci const void *src, size_t size) 6462306a36Sopenharmony_ci{ 6562306a36Sopenharmony_ci return copy_to_sockptr_offset((sockptr_t) dst, offset, src, size); 6662306a36Sopenharmony_ci} 6762306a36Sopenharmony_ci 6862306a36Sopenharmony_cistatic inline void *kvmemdup_bpfptr(bpfptr_t src, size_t len) 6962306a36Sopenharmony_ci{ 7062306a36Sopenharmony_ci void *p = kvmalloc(len, GFP_USER | __GFP_NOWARN); 7162306a36Sopenharmony_ci 7262306a36Sopenharmony_ci if (!p) 7362306a36Sopenharmony_ci return ERR_PTR(-ENOMEM); 7462306a36Sopenharmony_ci if (copy_from_bpfptr(p, src, len)) { 7562306a36Sopenharmony_ci kvfree(p); 7662306a36Sopenharmony_ci return ERR_PTR(-EFAULT); 7762306a36Sopenharmony_ci } 7862306a36Sopenharmony_ci return p; 7962306a36Sopenharmony_ci} 8062306a36Sopenharmony_ci 8162306a36Sopenharmony_cistatic inline long strncpy_from_bpfptr(char *dst, bpfptr_t src, size_t count) 8262306a36Sopenharmony_ci{ 8362306a36Sopenharmony_ci if (bpfptr_is_kernel(src)) 8462306a36Sopenharmony_ci return strncpy_from_kernel_nofault(dst, src.kernel, count); 8562306a36Sopenharmony_ci return strncpy_from_user(dst, src.user, count); 8662306a36Sopenharmony_ci} 8762306a36Sopenharmony_ci 8862306a36Sopenharmony_ci#endif /* _LINUX_BPFPTR_H */ 89