Reland copy file range san

compiler-rt/lib/sanitizer_common/sanitizer_common_syscalls.inc

@@ -3205,6 +3205,28 @@ POST_SYSCALL(futex)
   COMMON_SYSCALL_BLOCKING_END();
 }
 
+PRE_SYSCALL(copy_file_range)
+(int fdin, __sanitizer___kernel_off_t *offin, int fdout,
+ __sanitizer___kernel_off_t *offout, SIZE_T size, unsigned int flags) {
+  if (offin != nullptr) {
+    PRE_READ(offin, sizeof(*offin));
+  }
+  if (offout != nullptr) {
+    PRE_READ(offout, sizeof(*offout));
+  }
+}
+
+POST_SYSCALL(copy_file_range)
+(SSIZE_T, int fdin, __sanitizer___kernel_off_t *offin, int fdout,
+ __sanitizer___kernel_off_t *offout, SIZE_T size, unsigned int flags) {
+  if (offin != nullptr) {
+    POST_WRITE(offin, sizeof(*offin));
+  }
+  if (offout != nullptr) {
+    POST_WRITE(offout, sizeof(*offout));
+  }
+}
+
 }  // extern "C"
 
 #  undef PRE_SYSCALL

compiler-rt/test/sanitizer_common/TestCases/Linux/copy_file_range.c

@@ -0,0 +1,42 @@
+// RUN: %clangxx -O0 %s -D_FILE_OFFSET_BITS=64 -o %t
+
+// REQUIRES: glibc
+
+#ifndef _GNU_SOURCE
+#  define _GNU_SOURCE
+#endif
+#include <assert.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+
+#if !defined(__GLIBC_PREREQ)
+#  define __GLIBC_PREREQ(a, b) 0
+#endif
+
+#if !__GLIBC_PREREQ(2, 27)
+#  define copy_file_range(a, b, c, d, e, f)                                    \
+    (ssize_t) syscall(__NR_copy_file_range, a, b, c, d, e, f)
+#endif
+
+int main(void) {
+  int fdin = open("/proc/self/maps", O_RDONLY);
+  assert(fdin > 0);
+  char tmp[] = "/tmp/map.XXXXXX";
+  int fdout = mkstemp(tmp);
+  assert(fdout > 0);
+  off_t offin = -1, offout = 0;
+  ssize_t cpy = copy_file_range(fdin, &offin, fdout, &offout, 8, 0);
+  assert(cpy < 0);
+  offin = 0;
+  offout = 16;
+  cpy = copy_file_range(fdin, &offin, fdout, &offout, 8, 0);
+  assert(cpy < 0);
+  offout = 0;
+  cpy = copy_file_range(fdin, &offin, fdout, &offout, 8, 0);
+  assert(cpy == 8);
+  close(fdout);
+  close(fdin);
+  return 0;
+}