From 88f1516a323da620b8db8281239f65b29ff13c57 Mon Sep 17 00:00:00 2001
From: Cliff Frey <cliff@meraki.com>
Date: Fri, 15 Feb 2013 14:59:20 -0800
Subject: [PATCH] linuxmodule: correctly zero out packet txflags in linux
 2.6.32

Signed-off-by: Cliff Frey <cliff@meraki.com>
---
 config-linuxmodule.h.in |  3 +++
 configure               | 57 +++++++++++++++++++++++++++++++++++++++++
 configure.in            | 10 ++++++++
 lib/packet.cc           |  3 +++
 4 files changed, 73 insertions(+)

diff --git a/config-linuxmodule.h.in b/config-linuxmodule.h.in
index 05d5015c01..ab84a9a78f 100644
--- a/config-linuxmodule.h.in
+++ b/config-linuxmodule.h.in
@@ -91,6 +91,9 @@
 /* Define if 'struct skb_shared_info' has an 'ip6_frag_id' member. */
 #undef HAVE_LINUX_SKB_SHINFO_IP6_FRAG_ID
 
+/* Define if 'struct skb_shared_info' has an 'tx_flags.flags' member. */
+#undef HAVE_LINUX_SKB_SHINFO_TX_FLAGS_UNION
+
 /* Define if 'struct skb_shared_info' has an 'tx_flags' member defining 'SKBTX_DEV_ZEROCOPY'. */
 #undef HAVE_LINUX_SKB_SHINFO_TX_FLAGS_SKBTX_DEV_ZEROCOPY
 
diff --git a/configure b/configure
index 91d934406a..610faa4633 100755
--- a/configure
+++ b/configure
@@ -11522,6 +11522,63 @@ $as_echo "#define HAVE_LINUX_SKB_SHINFO_TX_FLAGS_SKBTX_DEV_ZEROCOPY 1" >>confdef
 
     fi
 
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether skb_shinfo has tx_flags.flags" >&5
+$as_echo_n "checking whether skb_shinfo has tx_flags.flags... " >&6; }
+if ${ac_cv_linuxmodule_skb_shinfo_tx_flags_union+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+	cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#if HAVE_LINUXMODULE_2_6
+# define KBUILD_STR(s)		#s
+# define KBUILD_BASENAME	KBUILD_STR(click)
+# define KBUILD_MODNAME		KBUILD_STR(click)
+#endif
+#define new linux_new
+#define this linux_this
+#define delete linux_delete
+#define class linux_class
+#define virtual linux_virtual
+#define typename linux_typename
+#define private linux_private
+#define protected linux_protected
+#define public linux_public
+#define namespace linux_namespace
+#define false linux_false
+#define true linux_true
+#define CLICK_CXX_PROTECTED 1
+$linux_autoconf_include
+#include <asm/types.h>
+#include <linux/skbuff.h>
+int
+main ()
+{
+extern struct sk_buff *s; skb_shinfo(s)->tx_flags.flags = 0;
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  ac_cv_linuxmodule_skb_shinfo_tx_flags_union=yes
+else
+  ac_cv_linuxmodule_skb_shinfo_tx_flags_union=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_linuxmodule_skb_shinfo_tx_flags_union" >&5
+$as_echo "$ac_cv_linuxmodule_skb_shinfo_tx_flags_union" >&6; }
+    if test $ac_cv_linuxmodule_skb_shinfo_tx_flags_union = yes; then
+
+$as_echo "#define HAVE_LINUX_SKB_SHINFO_TX_FLAGS_UNION 1" >>confdefs.h
+
+    fi
+
     { $as_echo "$as_me:${as_lineno-$LINENO}: checking for device polling kernel extension" >&5
 $as_echo_n "checking for device polling kernel extension... " >&6; }
 if ${ac_cv_linuxmodule_net_device_polling+:} false; then :
diff --git a/configure.in b/configure.in
index c2771cac4d..fd06769b49 100644
--- a/configure.in
+++ b/configure.in
@@ -1490,6 +1490,16 @@ void f1(int64_t) { // will fail if long long and int64_t are the same type
 	AC_DEFINE([HAVE_LINUX_SKB_SHINFO_TX_FLAGS_SKBTX_DEV_ZEROCOPY], [1], [Define if 'struct skb_shared_info' has an 'tx_flags' member defining 'SKBTX_DEV_ZEROCOPY'.])
     fi
 
+    AC_CACHE_CHECK([whether skb_shinfo has tx_flags.flags], [ac_cv_linuxmodule_skb_shinfo_tx_flags_union],
+	[AC_LANG_C
+	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([CLICK_LINUXMODULE_PROLOGUE()[
+#include <linux/skbuff.h>]],
+[[extern struct sk_buff *s; skb_shinfo(s)->tx_flags.flags = 0;]])],
+	[ac_cv_linuxmodule_skb_shinfo_tx_flags_union=yes], [ac_cv_linuxmodule_skb_shinfo_tx_flags_union=no])])
+    if test $ac_cv_linuxmodule_skb_shinfo_tx_flags_union = yes; then
+	AC_DEFINE([HAVE_LINUX_SKB_SHINFO_TX_FLAGS_UNION], [1], [Define if 'struct skb_shared_info' has a 'tx_flags.flags' member.])
+    fi
+
     AC_CACHE_CHECK([for device polling kernel extension], [ac_cv_linuxmodule_net_device_polling],
 	[AC_LANG_C
 	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([CLICK_LINUXMODULE_PROLOGUE()[
diff --git a/lib/packet.cc b/lib/packet.cc
index 655e2728ce..65c35c063a 100644
--- a/lib/packet.cc
+++ b/lib/packet.cc
@@ -693,6 +693,9 @@ Packet::expensive_uniqueify(int32_t extra_headroom, int32_t extra_tailroom,
 # if HAVE_LINUX_SKB_SHINFO_IP6_FRAG_ID
     nskb_shinfo->ip6_frag_id = 0;
 # endif
+# if HAVE_LINUX_SKB_SHINFO_TX_FLAGS_UNION
+    nskb_shinfo->tx_flags.flags = 0;
+# endif
 # if HAVE_LINUX_SKB_SHINFO_TX_FLAGS_SKBTX_DEV_ZEROCOPY
     nskb_shinfo->tx_flags = 0;
 # endif