Adjust sanitizers for FreeBSD 64-bit inode update

Summary:
Very recently, FreeBSD 12 has been updated to use 64-bit inode numbers:
<https://svnweb.freebsd.org/changeset/base/318737>.  This entails many
user-visible changes, but for the sanitizers the modifications are
limited in scope:
* The `stat` and `lstat` syscalls were removed, and should be replaced
  with calls to `fstatat`.
* The `getdents` syscall was removed, and should be replaced with calls
  to `getdirentries`.
* The layout of `struct dirent` was changed to accomodate 64-bit inode
  numbers, and a new `d_off` field was added.
* The system header <sys/_types.h> now contains a macro `__INO64` to
  determine whether the system uses 64-bit inode numbers.

I tested these changes on both FreeBSD 12.0-CURRENT (after r318959,
which adds the `__INO64` macro), and FreeBSD 11.0-STABLE (which still
uses 32-bit inode numbers).

Reviewers: emaste, kcc, vitalybuka, kubamracek

Reviewed By: vitalybuka

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33600


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@304658 91177308-0d34-0410-b5e6-96231b3b80d8

Author: DimitryAndric

lib/sanitizer_common/sanitizer_linux.cc

@@ -62,8 +62,6 @@
 #if SANITIZER_FREEBSD
 #include <sys/exec.h>
 #include <sys/sysctl.h>
-#include <vm/vm_param.h>
-#include <vm/pmap.h>
 #include <machine/atomic.h>
 extern "C" {
 // <sys/umtx.h> must be included after <errno.h> and <sys/types.h> on
@@ -227,7 +225,8 @@ static void kernel_stat_to_stat(struct kernel_stat *in, struct stat *out) {
 
 uptr internal_stat(const char *path, void *buf) {
 #if SANITIZER_FREEBSD
-  return internal_syscall(SYSCALL(stat), path, buf);
+  return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path,
+                          (uptr)buf, 0);
 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
   return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path,
                           (uptr)buf, 0);
@@ -251,7 +250,8 @@ uptr internal_stat(const char *path, void *buf) {
 
 uptr internal_lstat(const char *path, void *buf) {
 #if SANITIZER_FREEBSD
-  return internal_syscall(SYSCALL(lstat), path, buf);
+  return internal_syscall(SYSCALL(fstatat), AT_FDCWD, (uptr)path,
+                          (uptr)buf, AT_SYMLINK_NOFOLLOW);
 #elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
   return internal_syscall(SYSCALL(newfstatat), AT_FDCWD, (uptr)path,
                          (uptr)buf, AT_SYMLINK_NOFOLLOW);
@@ -594,7 +594,9 @@ uptr internal_getppid() {
 }
 
 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count) {
-#if SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
+#if SANITIZER_FREEBSD
+  return internal_syscall(SYSCALL(getdirentries), fd, (uptr)dirp, count, NULL);
+#elif SANITIZER_USES_CANONICAL_LINUX_SYSCALLS
   return internal_syscall(SYSCALL(getdents64), fd, (uptr)dirp, count);
 #else
   return internal_syscall(SYSCALL(getdents), fd, (uptr)dirp, count);

lib/sanitizer_common/sanitizer_platform_limits_posix.h

@@ -23,6 +23,9 @@
 // incorporates the map structure.
 # define GET_LINK_MAP_BY_DLOPEN_HANDLE(handle) \
     ((link_map*)((handle) == nullptr ? nullptr : ((char*)(handle) + 544)))
+// Get sys/_types.h, because that tells us whether 64-bit inodes are
+// used in struct dirent below.
+#include <sys/_types.h>
 #else
 # define GET_LINK_MAP_BY_DLOPEN_HANDLE(handle) ((link_map*)(handle))
 #endif  // !SANITIZER_FREEBSD
@@ -485,7 +488,12 @@ namespace __sanitizer {
   };
 #elif SANITIZER_FREEBSD
   struct __sanitizer_dirent {
+#if defined(__INO64)
+    unsigned long long d_fileno;
+    unsigned long long d_off;
+#else
     unsigned int d_fileno;
+#endif
     unsigned short d_reclen;
     // more fields that we don't care about
   };