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