diff options
Diffstat (limited to 'include/linux/uaccess.h')
| -rw-r--r-- | include/linux/uaccess.h | 106 |
1 files changed, 57 insertions, 49 deletions
diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h index ac0394087f7d..afb18f198843 100644 --- a/include/linux/uaccess.h +++ b/include/linux/uaccess.h @@ -10,46 +10,6 @@ #include <asm/uaccess.h> -#ifdef CONFIG_SET_FS -/* - * Force the uaccess routines to be wired up for actual userspace access, - * overriding any possible set_fs(KERNEL_DS) still lingering around. Undone - * using force_uaccess_end below. - */ -static inline mm_segment_t force_uaccess_begin(void) -{ - mm_segment_t fs = get_fs(); - - set_fs(USER_DS); - return fs; -} - -static inline void force_uaccess_end(mm_segment_t oldfs) -{ - set_fs(oldfs); -} -#else /* CONFIG_SET_FS */ -typedef struct { - /* empty dummy */ -} mm_segment_t; - -#ifndef TASK_SIZE_MAX -#define TASK_SIZE_MAX TASK_SIZE -#endif - -#define uaccess_kernel() (false) -#define user_addr_max() (TASK_SIZE_MAX) - -static inline mm_segment_t force_uaccess_begin(void) -{ - return (mm_segment_t) { }; -} - -static inline void force_uaccess_end(mm_segment_t oldfs) -{ -} -#endif /* CONFIG_SET_FS */ - /* * Architectures should provide two primitives (raw_copy_{to,from}_user()) * and get rid of their private instances of copy_{to,from}_user() and @@ -98,20 +58,28 @@ static inline void force_uaccess_end(mm_segment_t oldfs) static __always_inline __must_check unsigned long __copy_from_user_inatomic(void *to, const void __user *from, unsigned long n) { - instrument_copy_from_user(to, from, n); + unsigned long res; + + instrument_copy_from_user_before(to, from, n); check_object_size(to, n, false); - return raw_copy_from_user(to, from, n); + res = raw_copy_from_user(to, from, n); + instrument_copy_from_user_after(to, from, n, res); + return res; } static __always_inline __must_check unsigned long __copy_from_user(void *to, const void __user *from, unsigned long n) { + unsigned long res; + might_fault(); + instrument_copy_from_user_before(to, from, n); if (should_fail_usercopy()) return n; - instrument_copy_from_user(to, from, n); check_object_size(to, n, false); - return raw_copy_from_user(to, from, n); + res = raw_copy_from_user(to, from, n); + instrument_copy_from_user_after(to, from, n, res); + return res; } /** @@ -155,8 +123,9 @@ _copy_from_user(void *to, const void __user *from, unsigned long n) unsigned long res = n; might_fault(); if (!should_fail_usercopy() && likely(access_ok(from, n))) { - instrument_copy_from_user(to, from, n); + instrument_copy_from_user_before(to, from, n); res = raw_copy_from_user(to, from, n); + instrument_copy_from_user_after(to, from, n, res); } if (unlikely(res)) memset(to + (n - res), 0, res); @@ -188,7 +157,7 @@ _copy_to_user(void __user *, const void *, unsigned long); static __always_inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n) { - if (likely(check_copy_size(to, n, false))) + if (check_copy_size(to, n, false)) n = _copy_from_user(to, from, n); return n; } @@ -196,7 +165,7 @@ copy_from_user(void *to, const void __user *from, unsigned long n) static __always_inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n) { - if (likely(check_copy_size(from, n, true))) + if (check_copy_size(from, n, true)) n = _copy_to_user(to, from, n); return n; } @@ -271,6 +240,28 @@ static inline bool pagefault_disabled(void) */ #define faulthandler_disabled() (pagefault_disabled() || in_atomic()) +#ifndef CONFIG_ARCH_HAS_SUBPAGE_FAULTS + +/** + * probe_subpage_writeable: probe the user range for write faults at sub-page + * granularity (e.g. arm64 MTE) + * @uaddr: start of address range + * @size: size of address range + * + * Returns 0 on success, the number of bytes not probed on fault. + * + * It is expected that the caller checked for the write permission of each + * page in the range either by put_user() or GUP. The architecture port can + * implement a more efficient get_user() probing if the same sub-page faults + * are triggered by either a read or a write. + */ +static inline size_t probe_subpage_writeable(char __user *uaddr, size_t size) +{ + return 0; +} + +#endif /* CONFIG_ARCH_HAS_SUBPAGE_FAULTS */ + #ifndef ARCH_HAS_NOCACHE_UACCESS static inline __must_check unsigned long @@ -368,6 +359,25 @@ long strncpy_from_user_nofault(char *dst, const void __user *unsafe_addr, long count); long strnlen_user_nofault(const void __user *unsafe_addr, long count); +#ifndef __get_kernel_nofault +#define __get_kernel_nofault(dst, src, type, label) \ +do { \ + type __user *p = (type __force __user *)(src); \ + type data; \ + if (__get_user(data, p)) \ + goto label; \ + *(type *)dst = data; \ +} while (0) + +#define __put_kernel_nofault(dst, src, type, label) \ +do { \ + type __user *p = (type __force __user *)(dst); \ + type data = *(type *)src; \ + if (__put_user(data, p)) \ + goto label; \ +} while (0) +#endif + /** * get_kernel_nofault(): safely attempt to read from a location * @val: read into this variable @@ -401,8 +411,6 @@ static inline void user_access_restore(unsigned long flags) { } #endif #ifdef CONFIG_HARDENED_USERCOPY -void usercopy_warn(const char *name, const char *detail, bool to_user, - unsigned long offset, unsigned long len); void __noreturn usercopy_abort(const char *name, const char *detail, bool to_user, unsigned long offset, unsigned long len); |