feat: use close_range on linux to close fds

zu1k · Jun 14, 2023 · ba3ac3c · ba3ac3c
1 parent 024e540
commit ba3ac3c
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Showing 3 changed files with 7 additions and 1 deletion.
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp
@@ -243,6 +243,10 @@ uptr internal_close(fd_t fd) {
   return internal_syscall(SYSCALL(close), fd);
 }
 
+uptr internal_close_range(fd_t fd, fd_t max_fd, int flags) {
+  return internal_syscall(SYSCALL(close_range), fd, max_fd, flags);
+}
+
 uptr internal_open(const char *filename, int flags) {
 #    if SANITIZER_LINUX
   return internal_syscall(SYSCALL(openat), AT_FDCWD, (uptr)filename, flags);

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_posix.h b/compiler-rt/lib/sanitizer_common/sanitizer_posix.h
@@ -29,6 +29,7 @@ namespace __sanitizer {
 uptr internal_open(const char *filename, int flags);
 uptr internal_open(const char *filename, int flags, u32 mode);
 uptr internal_close(fd_t fd);
+uptr internal_close_range(fd_t fd, fd_t max_fd, int flags);
 
 uptr internal_read(fd_t fd, void *buf, uptr count);
 uptr internal_write(fd_t fd, const void *buf, uptr count);

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_posix_libcdep.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_posix_libcdep.cpp
@@ -462,7 +462,8 @@ pid_t StartSubprocess(const char *program, const char *const argv[],
       internal_close(stderr_fd);
     }
 
-    for (int fd = sysconf(_SC_OPEN_MAX); fd > 2; fd--) internal_close(fd);
+    // for (int fd = sysconf(_SC_OPEN_MAX); fd > 2; fd--) internal_close(fd);
+    internal_close_range(3, ~0U, CLOSE_RANGE_UNSHARE);
 
     internal_execve(program, const_cast<char **>(&argv[0]),
                     const_cast<char *const *>(envp));