hurd: Ignore bytes beyond sockaddr length for AF_UNIX

5 files changed, 22 insertions, 8 deletions

diff --git a/ChangeLog b/ChangeLog
index 4584975f3e..b3cdd15919 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -45,6 +45,16 @@
 	_IOT__IOTBASE_uint64_t, _IOT__IOTBASE_size_t, _IOT__IOTBASE_ssize_t,
 	_IOTBASE_unsigned, _IOTBASE_signed): Define macros.
 
+	[BZ #17944]
+	* hurd/hurdsocket.h: New file, defines _hurd_sun_path_dupa which
+	duplicates ADDR->sun_path with sockaddr LEN limitation.
+	* sysdeps/mach/hurd/connect.c: Include <string.h>
+	(__connect): Give result of _hurd_sun_path_dupa to name lookup.
+	* sysdeps/mach/hurd/sendmsg.c: Likewise.
+	* sysdeps/mach/hurd/sendto.c: Likewise.
+	* sysdeps/mach/hurd/bind.c: Call _hurd_sun_path_dupa instead of
+	implementing it by hand.
+
 2015-02-06  Roland McGrath  <roland@hack.frob.com>
 
 	* sysdeps/arm/sysdep.h [!PROF] [ARCH_HAS_T2 && !PIC] (LDR_GLOBAL):
diff --git a/sysdeps/mach/hurd/bind.c b/sysdeps/mach/hurd/bind.c
index de2d3f45a0..4b09be3635 100644
--- a/sysdeps/mach/hurd/bind.c
+++ b/sysdeps/mach/hurd/bind.c
@@ -25,7 +25,7 @@
 #include <stddef.h>
 #include <hurd/ifsock.h>
 #include <sys/un.h>
-#include <string.h>
+#include "hurd/hurdsocket.h"
 
 /* Give the socket FD the local address ADDR (which is LEN bytes long).  */
 int
@@ -37,13 +37,11 @@ __bind  (int fd, __CONST_SOCKADDR_ARG addrarg, socklen_t len)
 
   if (addr->sun_family == AF_LOCAL)
     {
+      char *name = _hurd_sun_path_dupa (addr, len);
       /* For the local domain, we must create a node in the filesystem
 	 using the ifsock translator and then fetch the address from it.  */
       file_t dir, node, ifsock;
-      char name[len - offsetof (struct sockaddr_un, sun_path) + 1], *n;
-
-      strncpy (name, addr->sun_path, sizeof name - 1);
-      name[sizeof name - 1] = '\0'; /* Make sure */
+      char *n;
 
       dir = __file_name_split (name, &n);
       if (dir == MACH_PORT_NULL)
diff --git a/sysdeps/mach/hurd/connect.c b/sysdeps/mach/hurd/connect.c
index f581c19937..43120eebc8 100644
--- a/sysdeps/mach/hurd/connect.c
+++ b/sysdeps/mach/hurd/connect.c
@@ -22,6 +22,7 @@
 #include <hurd/socket.h>
 #include <sys/un.h>
 #include <hurd/ifsock.h>
+#include "hurd/hurdsocket.h"
 
 /* Open a connection on socket FD to peer at ADDR (which LEN bytes long).
    For connectionless socket types, just set the default address to send to
@@ -36,9 +37,10 @@ __connect (int fd, __CONST_SOCKADDR_ARG addrarg, socklen_t len)
 
   if (addr->sun_family == AF_LOCAL)
     {
+      char *name = _hurd_sun_path_dupa (addr, len);
       /* For the local domain, we must look up the name as a file and talk
 	 to it with the ifsock protocol.  */
-      file_t file = __file_name_lookup (addr->sun_path, 0, 0);
+      file_t file = __file_name_lookup (name, 0, 0);
       if (file == MACH_PORT_NULL)
 	return -1;
       err = __ifsock_getsockaddr (file, &aport);
diff --git a/sysdeps/mach/hurd/sendmsg.c b/sysdeps/mach/hurd/sendmsg.c
index e375e242ef..34fd09c240 100644
--- a/sysdeps/mach/hurd/sendmsg.c
+++ b/sysdeps/mach/hurd/sendmsg.c
@@ -24,6 +24,7 @@
 #include <hurd/fd.h>
 #include <hurd/ifsock.h>
 #include <hurd/socket.h>
+#include "hurd/hurdsocket.h"
 
 /* Send a message described MESSAGE on socket FD.
    Returns the number of bytes sent, or -1 for errors.  */
@@ -104,9 +105,10 @@ __libc_sendmsg (int fd, const struct msghdr *message, int flags)
     {
       if (addr->sun_family == AF_LOCAL)
 	{
+	  char *name = _hurd_sun_path_dupa (addr, addr_len);
 	  /* For the local domain, we must look up the name as a file
 	     and talk to it with the ifsock protocol.  */
-	  file_t file = __file_name_lookup (addr->sun_path, 0, 0);
+	  file_t file = __file_name_lookup (name, 0, 0);
 	  if (file == MACH_PORT_NULL)
 	    {
 	      if (dealloc)
diff --git a/sysdeps/mach/hurd/sendto.c b/sysdeps/mach/hurd/sendto.c
index 2b18b04b80..577d28892c 100644
--- a/sysdeps/mach/hurd/sendto.c
+++ b/sysdeps/mach/hurd/sendto.c
@@ -22,6 +22,7 @@
 #include <hurd/fd.h>
 #include <hurd/ifsock.h>
 #include <hurd/socket.h>
+#include "hurd/hurdsocket.h"
 
 /* Send N bytes of BUF on socket FD to peer at address ADDR (which is
    ADDR_LEN bytes long).  Returns the number sent, or -1 for errors.  */
@@ -47,9 +48,10 @@ __sendto (int fd,
 
       if (addr->sun_family == AF_LOCAL)
 	{
+	  char *name = _hurd_sun_path_dupa (addr, addr_len);
 	  /* For the local domain, we must look up the name as a file and talk
 	     to it with the ifsock protocol.  */
-	  file_t file = __file_name_lookup (addr->sun_path, 0, 0);
+	  file_t file = __file_name_lookup (name, 0, 0);
 	  if (file == MACH_PORT_NULL)
 	    return errno;
 	  err_port = __ifsock_getsockaddr (file, aport);