[PATCH] af_alg: don’t leak file descriptors into children

[Paul Eggert]

* lib/af_alg.c (alg_socket): Use SOCK_CLOEXEC when creating sockets.
This code should be compiled only on recent GNU/Linux platforms
so we shouldn’t have to also depend on the accept4 module.
---
 ChangeLog    | 5 +++++
 lib/af_alg.c | 4 ++--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index c4e155392..818d3a602 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2018-05-09  Paul Eggert  <address@hidden>
 
+       af_alg: don’t leak file descriptors into children
+       * lib/af_alg.c (alg_socket): Use SOCK_CLOEXEC when creating sockets.
+       This code should be compiled only on recent GNU/Linux platforms
+       so we shouldn’t have to also depend on the accept4 module.
+
        af_alg: coalesce socket creation
        * lib/af_alg.c (alg_socket): New function.
        (afalg_buffer, afalg_stream): Use it.  This avoids some
diff --git a/lib/af_alg.c b/lib/af_alg.c
index ca3dd0323..c85140a33 100644
--- a/lib/af_alg.c
+++ b/lib/af_alg.c
@@ -49,11 +49,11 @@ alg_socket (char const *alg)
     if (i == sizeof salg.salg_name - 1)
       return -EINVAL;
 
-  int cfd = socket (AF_ALG, SOCK_SEQPACKET, 0);
+  int cfd = socket (AF_ALG, SOCK_SEQPACKET | SOCK_CLOEXEC, 0);
   if (cfd < 0)
     return -EAFNOSUPPORT;
   int ofd = (bind (cfd, (struct sockaddr *) &salg, sizeof salg) == 0
-             ? accept (cfd, NULL, 0)
+             ? accept4 (cfd, NULL, 0, SOCK_CLOEXEC)
              : -1);
   close (cfd);
   return ofd < 0 ? -EAFNOSUPPORT : ofd;
-- 
2.17.0