* process.c (redirect_close, parent_redirect_close): should not close

  reserved FD. It should be closed in the exec system call due to the
  O_CLOEXEC or FD_CLOEXEC flag. [Bug #11353] [ruby-core:69977]
    
* process.c (close_unless_reserved): new function to close FD unless
  it is reserved for internal communication.
      
* thread_pthread.c (rb_reserved_fd_p): should check owner_process pid
  to avoid false positive in forked child process.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@51255 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 14 insertions, 4 deletions

diff --git a/process.c b/process.c
index 12eb624fe3..ac724639f9 100644
--- a/process.c
+++ b/process.c
@@ -294,6 +294,16 @@ extern ID ruby_static_id_status;
 #define ALWAYS_NEED_ENVP 0
 #endif
 
+static inline int close_unless_reserved(fd)
+{
+    /* Do nothing to the reserved fd because it should be closed in exec(2)
+       due to the O_CLOEXEC or FD_CLOEXEC flag. */
+    if (rb_reserved_fd_p(fd)) { /* async-signal-safe */
+        return 0;
+    }
+    return close(fd); /* async-signal-safe */
+}
+
 /*#define DEBUG_REDIRECT*/
 #if defined(DEBUG_REDIRECT)
 
@@ -342,7 +352,7 @@ static int
 redirect_close(int fd)
 {
     int ret;
-    ret = close(fd);
+    ret = close_unless_reserved(fd);
     ttyprintf("close(%d) => %d\n", fd, ret);
     return ret;
 }
@@ -360,7 +370,7 @@ static int
 parent_redirect_close(int fd)
 {
     int ret;
-    ret = close(fd);
+    ret = close_unless_reserved(fd);
     ttyprintf("parent_close(%d) => %d\n", fd, ret);
     return ret;
 }
@@ -368,9 +378,9 @@ parent_redirect_close(int fd)
 #else
 #define redirect_dup(oldfd) dup(oldfd)
 #define redirect_dup2(oldfd, newfd) dup2((oldfd), (newfd))
-#define redirect_close(fd) close(fd)
+#define redirect_close(fd) close_unless_reserved(fd)
 #define parent_redirect_open(pathname, flags, perm) rb_cloexec_open((pathname), (flags), (perm))
-#define parent_redirect_close(fd) close(fd)
+#define parent_redirect_close(fd) close_unless_reserved(fd)
 #endif
 
 /*