Backport r831641 from the trunk.

Set file/socket descriptor to -1 before close(), so that there is no chance
of returning an already closed FD from apr_os_file_get()/apr_os_sock_get().

git-svn-id: http://svn.apache.org/repos/asf/apr/apr/branches/1.4.x@831642 13f79535-47bb-0310-9956-ffa450edef68

2 files changed, 19 insertions, 4 deletions

diff --git a/file_io/unix/open.c b/file_io/unix/open.c
index e10fc3dda..bf3b43b6a 100644
--- a/file_io/unix/open.c
+++ b/file_io/unix/open.c
@@ -29,10 +29,14 @@
 static apr_status_t file_cleanup(apr_file_t *file, int is_child)
 {
     apr_status_t rv = APR_SUCCESS;
+    int fd = file->filedes;
 
-    if (close(file->filedes) == 0) {
-        file->filedes = -1;
+    /* Set file descriptor to -1 before close(), so that there is no
+     * chance of returning an already closed FD from apr_os_file_get().
+     */
+    file->filedes = -1;
 
+    if (close(fd) == 0) {
         /* Only the parent process should delete the file! */
         if (!is_child && (file->flags & APR_DELONCLOSE)) {
             unlink(file->fname);
@@ -44,6 +48,9 @@ static apr_status_t file_cleanup(apr_file_t *file, int is_child)
 #endif
     }
     else {
+        /* Restore, close() was not successful. */
+        file->filedes = fd;
+
         /* Are there any error conditions other than EINTR or EBADF? */
         rv = errno;
     }
diff --git a/network_io/unix/sockets.c b/network_io/unix/sockets.c
index a379b7bdd..5552460ed 100644
--- a/network_io/unix/sockets.c
+++ b/network_io/unix/sockets.c
@@ -31,12 +31,20 @@ static char generic_inaddr_any[16] = {0}; /* big enough for IPv4 or IPv6 */
 static apr_status_t socket_cleanup(void *sock)
 {
     apr_socket_t *thesocket = sock;
+    int sd = thesocket->socketdes;
 
-    if (close(thesocket->socketdes) == 0) {
-        thesocket->socketdes = -1;
+    /* Set socket descriptor to -1 before close(), so that there is no
+     * chance of returning an already closed FD from apr_os_sock_get().
+     */
+    thesocket->socketdes = -1;
+
+    if (close(sd) == 0) {
         return APR_SUCCESS;
     }
     else {
+        /* Restore, close() was not successful. */
+        thesocket->socketdes = sd;
+
         return errno;
     }
 }