add initial clang support

jvoisin · Jun 25, 2023 · fe14962 · fe14962
1 parent adae76a
commit fe14962
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Showing 10 changed files with 157 additions and 61 deletions.
diff --git a/include/fortify-headers.h b/include/fortify-headers.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2015-2016 Dimitris Papastamos <sin@2f30.org>
+ * Copyright (C) 2022 q66 <q66@chimera-linux.org>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted.
@@ -16,10 +17,30 @@
 #ifndef _FORTIFY_HEADERS_H
 #define _FORTIFY_HEADERS_H
 
+#ifdef __clang__
+
+/* clang uses overloads; see https://github.com/llvm/llvm-project/issues/53516 */
+#define _FORTIFY_POSN(n) const __attribute__((__pass_object_size__(n)))
+/* we can't use extern inline with overloads without making them external */
+#define _FORTIFY_INLINE static __inline__ \
+	__attribute__((__always_inline__,__artificial__,__overloadable__))
+
+#else /* !__clang__ */
+
+#define _FORTIFY_POSN(n)
+#define _FORTIFY_INLINE extern __inline__ \
+	__attribute__((__always_inline__,__gnu_inline__,__artificial__))
+
+#endif /* __clang__ */
+
+#define _FORTIFY_POS0 _FORTIFY_POSN(0)
+#define _FORTIFY_POS1 _FORTIFY_POSN(1)
+#define _FORTIFY_POS2 _FORTIFY_POSN(2)
+
 #define _FORTIFY_STR(s) #s
 #define _FORTIFY_ORIG(p,fn) __typeof__(fn) __orig_##fn __asm__(_FORTIFY_STR(p) #fn)
-#define _FORTIFY_FN(fn) _FORTIFY_ORIG(__USER_LABEL_PREFIX__,fn); \
-	extern __inline__ __attribute__((__always_inline__,__gnu_inline__,__artificial__))
+#define _FORTIFY_FNB(fn) _FORTIFY_ORIG(__USER_LABEL_PREFIX__,fn)
+#define _FORTIFY_FN(fn) _FORTIFY_FNB(fn); _FORTIFY_INLINE
 
 
 /* Use __builtin_dynamic_object_size with _FORTIFY_SOURCE>2, if available.  */

diff --git a/include/poll.h b/include/poll.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2015-2016 Dimitris Papastamos <sin@2f30.org>
+ * Copyright (C) 2022 q66 <q66@chimera-linux.org>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted.
@@ -30,7 +31,7 @@ extern "C" {
 
 #undef poll
 
-_FORTIFY_FN(poll) int poll(struct pollfd *__f, nfds_t __n, int __s)
+_FORTIFY_FN(poll) int poll(struct pollfd * _FORTIFY_POS0 __f, nfds_t __n, int __s)
 {
 	size_t __b = __bos(__f, 0);
 
@@ -41,8 +42,8 @@ _FORTIFY_FN(poll) int poll(struct pollfd *__f, nfds_t __n, int __s)
 
 #if defined(_GNU_SOURCE) && !_REDIR_TIME64
 #undef ppoll
-_FORTIFY_FN(ppoll) int ppoll(struct pollfd *__f, nfds_t __n, const struct timespec *__s,
-                             const sigset_t *__m)
+_FORTIFY_FN(ppoll) int ppoll(struct pollfd * _FORTIFY_POS0 __f, nfds_t __n,
+                             const struct timespec *__s, const sigset_t *__m)
 {
 	size_t __b = __bos(__f, 0);
 

diff --git a/include/stdio.h b/include/stdio.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2015-2016 Dimitris Papastamos <sin@2f30.org>
+ * Copyright (C) 2022 q66 <q66@chimera-linux.org>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted.
@@ -37,7 +38,7 @@ extern "C" {
 #undef sprintf
 
 __access(write_only, 1, 2)
-_FORTIFY_FN(fgets) char *fgets(char *__s, int __n, FILE *__f)
+_FORTIFY_FN(fgets) char *fgets(char * _FORTIFY_POS0 __s, int __n, FILE *__f)
 {
 	size_t __b = __bos(__s, 0);
 
@@ -46,7 +47,8 @@ _FORTIFY_FN(fgets) char *fgets(char *__s, int __n, FILE *__f)
 	return __orig_fgets(__s, __n, __f);
 }
 
-_FORTIFY_FN(fread) size_t fread(void *__d, size_t __n, size_t __m, FILE *__f)
+_FORTIFY_FN(fread) size_t fread(void * _FORTIFY_POS0 __d, size_t __n,
+                                size_t __m, FILE *__f)
 {
 	size_t __b = __bos(__d, 0);
 
@@ -57,7 +59,8 @@ _FORTIFY_FN(fread) size_t fread(void *__d, size_t __n, size_t __m, FILE *__f)
 	return __orig_fread(__d, __n, __m, __f);
 }
 
-_FORTIFY_FN(fwrite) size_t fwrite(const void *__d, size_t __n, size_t __m, FILE *__f)
+_FORTIFY_FN(fwrite) size_t fwrite(const void * _FORTIFY_POS0 __d, size_t __n,
+                                  size_t __m, FILE *__f)
 {
 	size_t __b = __bos(__d, 0);
 
@@ -68,8 +71,8 @@ _FORTIFY_FN(fwrite) size_t fwrite(const void *__d, size_t __n, size_t __m, FILE
 	return __orig_fwrite(__d, __n, __m, __f);
 }
 
-_FORTIFY_FN(vsnprintf) int vsnprintf(char *__s, size_t __n, const char *__f,
-                                     __builtin_va_list __v)
+_FORTIFY_FN(vsnprintf) int vsnprintf(char * _FORTIFY_POS0 __s, size_t __n,
+                                     const char *__f, __builtin_va_list __v)
 {
 	size_t __b = __bos(__s, 0);
 
@@ -78,7 +81,8 @@ _FORTIFY_FN(vsnprintf) int vsnprintf(char *__s, size_t __n, const char *__f,
 	return __orig_vsnprintf(__s, __n, __f, __v);
 }
 
-_FORTIFY_FN(vsprintf) int vsprintf(char *__s, const char *__f, __builtin_va_list __v)
+_FORTIFY_FN(vsprintf) int vsprintf(char * _FORTIFY_POS0 __s, const char *__f,
+                                   __builtin_va_list __v)
 {
 	size_t __b = __bos(__s, 0);
 	int __r;
@@ -93,7 +97,23 @@ _FORTIFY_FN(vsprintf) int vsprintf(char *__s, const char *__f, __builtin_va_list
 	return __r;
 }
 
-_FORTIFY_FN(snprintf) int snprintf(char *__s, size_t __n, const char *__f, ...)
+#if defined(__has_builtin)
+#if __has_builtin(__builtin_va_arg_pack)
+
+/* clang is missing __builtin_va_arg_pack, so we cannot use these impls
+ * outside of gcc; we then have a few options:
+ *
+ * 1) using va_start/end and implementing these functions as static inline,
+ *    with inlining never happening; that means extra symbols with internal
+ *    linkage, which is not ideal
+ * 2) using macros; this is incompatible with c++ and since musl does not
+ *    have the __chk variants, we'd need to implement a body with intermediate
+ *    variables within the macro, which means more non-portable mess
+ * 3) not implementing these under clang, which is what we do for now
+ */
+
+_FORTIFY_FN(snprintf) int snprintf(char *__s, size_t __n,
+                                    const char *__f, ...)
 {
 	size_t __b = __bos(__s, 0);
 
@@ -117,6 +137,9 @@ _FORTIFY_FN(sprintf) int sprintf(char *__s, const char *__f, ...)
 	return __r;
 }
 
+#endif /* __has_builtin(__builtin_va_arg_pack) */
+#endif /* defined(__has_builtin) */
+
 #ifdef __cplusplus
 }
 #endif

diff --git a/include/stdlib.h b/include/stdlib.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2015-2016 Dimitris Papastamos <sin@2f30.org>
+ * Copyright (C) 2022 q66 <q66@chimera-linux.org>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted.
@@ -35,7 +36,8 @@ __extension__
 extern "C" {
 #endif
 
-#if defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
+/* FIXME clang */
+#if (defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) || defined(_BSD_SOURCE)) && !defined(__clang__)
 #undef realpath
 _FORTIFY_FN(realpath) char *realpath(const char *__p, char *__r)
 {

diff --git a/include/string.h b/include/string.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2015-2016 Dimitris Papastamos <sin@2f30.org>
+ * Copyright (C) 2022 q66 <q66@chimera-linux.org>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted.
@@ -38,7 +39,8 @@ extern "C" {
 
 __access(write_only, 1)
 __access(read_only, 2, 3)
-_FORTIFY_FN(memcpy) void *memcpy(void *__od, const void *__os, size_t __n)
+_FORTIFY_FN(memcpy) void *memcpy(void * _FORTIFY_POS0 __od,
+                                 const void * _FORTIFY_POS0 __os, size_t __n)
 {
 	size_t __bd = __bos(__od, 0);
 	size_t __bs = __bos(__os, 0);
@@ -57,7 +59,8 @@ _FORTIFY_FN(memcpy) void *memcpy(void *__od, const void *__os, size_t __n)
 
 __access(write_only, 1)
 __access(read_only, 2, 3)
-_FORTIFY_FN(memmove) void *memmove(void *__d, const void *__s, size_t __n)
+_FORTIFY_FN(memmove) void *memmove(void * _FORTIFY_POS0 __d,
+                                   const void * _FORTIFY_POS0 __s, size_t __n)
 {
 	size_t __bd = __bos(__d, 0);
 	size_t __bs = __bos(__s, 0);
@@ -68,7 +71,7 @@ _FORTIFY_FN(memmove) void *memmove(void *__d, const void *__s, size_t __n)
 }
 
 __access(write_only, 1)
-_FORTIFY_FN(memset) void *memset(void *__d, int __c, size_t __n)
+_FORTIFY_FN(memset) void *memset(void * _FORTIFY_POS0 __d, int __c, size_t __n)
 {
 	size_t __b = __bos(__d, 0);
 
@@ -83,7 +86,7 @@ _FORTIFY_FN(memset) void *memset(void *__d, int __c, size_t __n)
 #undef stpcpy
 __access(write_only, 1)
 __access(read_only, 2)
-_FORTIFY_FN(stpcpy) char *stpcpy(char *__d, const char *__s)
+_FORTIFY_FN(stpcpy) char *stpcpy(char * _FORTIFY_POS0 __d, const char *__s)
 {
 	size_t __n = strlen(__s) + 1;
 
@@ -102,7 +105,8 @@ _FORTIFY_FN(stpcpy) char *stpcpy(char *__d, const char *__s)
 #undef stpncpy
 __access(write_only, 1)
 __access(read_only, 2, 3)
-_FORTIFY_FN(stpncpy) char *stpncpy(char *__d, const char *__s, size_t __n)
+_FORTIFY_FN(stpncpy) char *stpncpy(char * _FORTIFY_POS0 __d, const char *__s,
+                                   size_t __n)
 {
 	/* trap if pointers are overlapping but not if dst == src.
 	 * gcc seems to like to generate code that relies on dst == src */
@@ -119,7 +123,7 @@ _FORTIFY_FN(stpncpy) char *stpncpy(char *__d, const char *__s, size_t __n)
 
 __access (read_write, 1)
 __access (read_only, 2)
-_FORTIFY_FN(strcat) char *strcat(char *__d, const char *__s)
+_FORTIFY_FN(strcat) char *strcat(char * _FORTIFY_POS0 __d, const char *__s)
 {
 	size_t __b = __bos(__d, 0);
 
@@ -130,7 +134,7 @@ _FORTIFY_FN(strcat) char *strcat(char *__d, const char *__s)
 
 __access (write_only, 1)
 __access (read_only, 2)
-_FORTIFY_FN(strcpy) char *strcpy(char *__d, const char *__s)
+_FORTIFY_FN(strcpy) char *strcpy(char * _FORTIFY_POS0 __d, const char *__s)
 {
 	size_t __n = strlen(__s) + 1;
 
@@ -148,7 +152,8 @@ _FORTIFY_FN(strcpy) char *strcpy(char *__d, const char *__s)
 
 __access (read_write, 1)
 __access (read_only, 2, 3)
-_FORTIFY_FN(strncat) char *strncat(char *__d, const char *__s, size_t __n)
+_FORTIFY_FN(strncat) char *strncat(char * _FORTIFY_POS0 __d, const char *__s,
+                                   size_t __n)
 {
 	size_t __b = __bos(__d, 0);
 
@@ -165,7 +170,8 @@ _FORTIFY_FN(strncat) char *strncat(char *__d, const char *__s, size_t __n)
 
 __access (write_only, 1)
 __access (read_only, 2, 3)
-_FORTIFY_FN(strncpy) char *strncpy(char *__d, const char *__s, size_t __n)
+_FORTIFY_FN(strncpy) char *strncpy(char * _FORTIFY_POS0 __d,
+                                   const char *__s, size_t __n)
 {
 	/* trap if pointers are overlapping but not if dst == src.
 	 * gcc seems to like to generate code that relies on dst == src */
@@ -183,7 +189,8 @@ _FORTIFY_FN(strncpy) char *strncpy(char *__d, const char *__s, size_t __n)
 #undef mempcpy
 __access(write_only, 1)
 __access(read_only, 2, 3)
-_FORTIFY_FN(mempcpy) void *mempcpy(void *__d, const void *__s, size_t __n)
+_FORTIFY_FN(mempcpy) void *mempcpy(void * _FORTIFY_POS0 __d,
+                                   const void * _FORTIFY_POS0 __s, size_t __n)
 {
 	size_t __bd = __bos(__d, 0);
 	size_t __bs = __bos(__s, 0);
@@ -199,7 +206,8 @@ _FORTIFY_FN(mempcpy) void *mempcpy(void *__d, const void *__s, size_t __n)
 #undef strlcpy
 __access (read_write, 1)
 __access (read_only, 2, 3)
-_FORTIFY_FN(strlcat) size_t strlcat(char *__d, const char *__s, size_t __n)
+_FORTIFY_FN(strlcat) size_t strlcat(char * _FORTIFY_POS0 __d,
+                                    const char *__s, size_t __n)
 {
 	size_t __b = __bos(__d, 0);
 
@@ -210,7 +218,8 @@ _FORTIFY_FN(strlcat) size_t strlcat(char *__d, const char *__s, size_t __n)
 
 __access (write_only, 1)
 __access (read_only, 2, 3)
-_FORTIFY_FN(strlcpy) size_t strlcpy(char *__d, const char *__s, size_t __n)
+_FORTIFY_FN(strlcpy) size_t strlcpy(char * _FORTIFY_POS0 __d,
+                                    const char *__s, size_t __n)
 {
 	size_t __b = __bos(__d, 0);
 

diff --git a/include/strings.h b/include/strings.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2015-2016 Dimitris Papastamos <sin@2f30.org>
+ * Copyright (C) 2022 q66 <q66@chimera-linux.org>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted.
@@ -30,7 +31,8 @@ extern "C" {
  || (defined(_XOPEN_SOURCE) && _XOPEN_SOURCE+0 < 700)
 #undef bcopy
 #undef bzero
-_FORTIFY_FN(bcopy) void bcopy(const void *__s, void *__d, size_t __n)
+_FORTIFY_FN(bcopy) void bcopy(const void * _FORTIFY_POS0 __s,
+                              void * _FORTIFY_POS0 __d, size_t __n)
 {
 	size_t __bd = __bos(__d, 0);
 	size_t __bs = __bos(__s, 0);
@@ -40,7 +42,7 @@ _FORTIFY_FN(bcopy) void bcopy(const void *__s, void *__d, size_t __n)
 	return __orig_bcopy(__s, __d, __n);
 }
 
-_FORTIFY_FN(bzero) void bzero(void *__s, size_t __n)
+_FORTIFY_FN(bzero) void bzero(void * _FORTIFY_POS0 __s, size_t __n)
 {
 	size_t __b = __bos(__s, 0);
 

diff --git a/include/sys/select.h b/include/sys/select.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2015-2016 Dimitris Papastamos <sin@2f30.org>
+ * Copyright (C) 2022 q66 <q66@chimera-linux.org>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted.
@@ -27,8 +28,14 @@ __extension__
 extern "C" {
 #endif
 
+#ifdef __clang__
+#define _FORTIFY_FD_POS0 const __attribute__((__pass_object_size__(0)))
+#else
+#define _FORTIFY_FD_POS0
+#endif
+
 static __inline__ __attribute__((__always_inline__,__gnu_inline__,__artificial__))
-void __fortify_FD_CLR(int __f, fd_set *__s)
+void __fortify_FD_CLR(int __f, fd_set * _FORTIFY_FD_POS0 __s)
 {
 	size_t __b = __bos(__s, 0);
 
@@ -38,7 +45,7 @@ void __fortify_FD_CLR(int __f, fd_set *__s)
 }
 
 static __inline__ __attribute__((__always_inline__,__gnu_inline__,__artificial__))
-void __fortify_FD_SET(int __f, fd_set *__s)
+void __fortify_FD_SET(int __f, fd_set * _FORTIFY_FD_POS0 __s)
 {
 	size_t __b = __bos(__s, 0);
 
@@ -47,6 +54,8 @@ void __fortify_FD_SET(int __f, fd_set *__s)
 	FD_SET(__f, __s);
 }
 
+#undef _FORTIFY_FD_POS0
+
 #undef FD_CLR
 #define FD_CLR(fd, set) __fortify_FD_CLR(fd, set)
 #undef FD_SET