[PATCH iproute2] tc: fix bpf compilation with old glibc

[PATCH iproute2] tc: fix bpf compilation with old glibc

[Nicolas Dichtel]

Error was:
f_bpf.o: In function `bpf_parse_opt':
f_bpf.c:(.text+0x88f): undefined reference to `secure_getenv'
m_bpf.o: In function `parse_bpf':
m_bpf.c:(.text+0x587): undefined reference to `secure_getenv'
collect2: error: ld returned 1 exit status

CC: Daniel Borkmann <daniel@iogearbox.net>
Fixes: 88eea5395483 ("tc: {f,m}_bpf: allow to retrieve uds path from env")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
---
 configure   | 49 +++++++++++++++++++++++++++++++++++++++++++++++--
 tc/Makefile |  6 ++++++
 tc/tc_bpf.h |  9 +++++++++
 3 files changed, 62 insertions(+), 2 deletions(-)

diff --git a/configure b/configure
index 3ae4c955ae8e..1eacdc67dbb9 100755
--- a/configure
+++ b/configure
@@ -289,12 +289,54 @@ check_mnl()
 	if ${PKG_CONFIG} libmnl --exists
 	then
 		echo "HAVE_MNL:=y" >>Config
-		echo -n "yes"
+		echo "yes"
 	else
-		echo -n "no"
+		echo "no"
 	fi
 }
 
+check_secure_getenv()
+{
+	#check if we have secure_getenv()
+	cat >$TMPDIR/secure_getenv_test.c <<EOF
+#include <stdlib.h>
+
+int main(int argc, char **argv)
+{
+	secure_getenv("foo");
+	return 0;
+}
+EOF
+
+	$CC -I$INCLUDE -o $TMPDIR/secure_getenv_test $TMPDIR/secure_getenv_test.c >/dev/null 2>&1
+	if [ $? -eq 0 ]
+	then
+		echo "HAVE_SECURE_GETENV:=y" >>Config
+		echo "yes"
+	else
+		#check if we have __secure_getenv()
+		cat >$TMPDIR/secure_getenv_test.c <<EOF
+#include <stdlib.h>
+
+int main(int argc, char **argv)
+{
+	__secure_getenv("foo");
+	return 0;
+}
+EOF
+
+		$CC -I$INCLUDE -o $TMPDIR/secure_getenv_test $TMPDIR/secure_getenv_test.c >/dev/null 2>&1
+		if [ $? -eq 0 ]
+		then
+			echo "HAVE___SECURE_GETENV:=y" >>Config
+			echo "yes"
+		else
+			echo "no"
+		fi
+	fi
+	rm -f $TMPDIR/secure_getenv_test.c $TMPDIR/secure_getenv_test
+}
+
 echo "# Generated config based on" $INCLUDE >Config
 check_toolchain
 
@@ -328,6 +370,9 @@ check_elf
 echo -n "libmnl support: "
 check_mnl
 
+echo -n "secure_getenv() support: "
+check_secure_getenv
+
 echo
 echo -n "docs:"
 check_docs
diff --git a/tc/Makefile b/tc/Makefile
index 56acbaa1ab13..d598fc29532f 100644
--- a/tc/Makefile
+++ b/tc/Makefile
@@ -7,6 +7,12 @@ include ../Config
 ifeq ($(IP_CONFIG_SETNS),y)
 	CFLAGS += -DHAVE_SETNS
 endif
+ifeq ($(HAVE_SECURE_GETENV),y)
+	CFLAGS += -DHAVE_SECURE_GETENV
+endif
+ifeq ($(HAVE___SECURE_GETENV),y)
+	CFLAGS += -DHAVE___SECURE_GETENV
+endif
 
 SHARED_LIBS ?= y
 
diff --git a/tc/tc_bpf.h b/tc/tc_bpf.h
index 2ad881219e68..2e4b1a985f05 100644
--- a/tc/tc_bpf.h
+++ b/tc/tc_bpf.h
@@ -21,12 +21,21 @@
 #include <errno.h>
 #include <stdio.h>
 #include <stdint.h>
+#include <stdlib.h>
 
 #include "utils.h"
 #include "bpf_scm.h"
 
 #define BPF_ENV_UDS	"TC_BPF_UDS"
 
+#ifndef HAVE_SECURE_GETENV
+#  ifdef HAVE___SECURE_GETENV
+#    define secure_getenv __secure_getenv
+#  else
+#    error neither secure_getenv nor __secure_getenv is available
+#  endif
+#endif
+
 int bpf_parse_string(char *arg, bool from_file, __u16 *bpf_len,
 		     char **bpf_string, bool *need_release,
 		     const char separator);
-- 
2.4.2

Re: [PATCH iproute2] tc: fix bpf compilation with old glibc

[Daniel Borkmann]

On 07/22/2015 02:29 PM, Nicolas Dichtel wrote:
> Error was:
> f_bpf.o: In function `bpf_parse_opt':
> f_bpf.c:(.text+0x88f): undefined reference to `secure_getenv'
> m_bpf.o: In function `parse_bpf':
> m_bpf.c:(.text+0x587): undefined reference to `secure_getenv'
> collect2: error: ld returned 1 exit status
>
> CC: Daniel Borkmann <daniel@iogearbox.net>
> Fixes: 88eea5395483 ("tc: {f,m}_bpf: allow to retrieve uds path from env")
> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>

Thanks Nicolas! I am thinking we should probably just stick to getenv()
and convert these two users.

Thanks,
Daniel

Re: [PATCH iproute2] tc: fix bpf compilation with old glibc

[Nicolas Dichtel]

Le 22/07/2015 15:05, Daniel Borkmann a écrit :
> On 07/22/2015 02:29 PM, Nicolas Dichtel wrote:
>> Error was:
>> f_bpf.o: In function `bpf_parse_opt':
>> f_bpf.c:(.text+0x88f): undefined reference to `secure_getenv'
>> m_bpf.o: In function `parse_bpf':
>> m_bpf.c:(.text+0x587): undefined reference to `secure_getenv'
>> collect2: error: ld returned 1 exit status
>>
>> CC: Daniel Borkmann <daniel@iogearbox.net>
>> Fixes: 88eea5395483 ("tc: {f,m}_bpf: allow to retrieve uds path from env")
>> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
>
> Thanks Nicolas! I am thinking we should probably just stick to getenv()
> and convert these two users.
As you want, I don't have a strong opinion on this. Stephen?


Regards,
Nicolas

Re: [PATCH iproute2] tc: fix bpf compilation with old glibc

[Stephen Hemminger]

On Wed, 22 Jul 2015 13:05:32 +0000
Daniel Borkmann <daniel@iogearbox.net> wrote:

> On 07/22/2015 02:29 PM, Nicolas Dichtel wrote:
> > Error was:
> > f_bpf.o: In function `bpf_parse_opt':
> > f_bpf.c:(.text+0x88f): undefined reference to `secure_getenv'
> > m_bpf.o: In function `parse_bpf':
> > m_bpf.c:(.text+0x587): undefined reference to `secure_getenv'
> > collect2: error: ld returned 1 exit status
> >
> > CC: Daniel Borkmann <daniel@iogearbox.net>
> > Fixes: 88eea5395483 ("tc: {f,m}_bpf: allow to retrieve uds path from env")
> > Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
> 
> Thanks Nicolas! I am thinking we should probably just stick to getenv()
> and convert these two users.
> 
> Thanks,
> Daniel

Yes, please use getenv() unless there is a obvious special
security requirement involved. 

[PATCH v2 iproute2] tc: fix bpf compilation with old glibc

[Nicolas Dichtel]

Error was:
f_bpf.o: In function `bpf_parse_opt':
f_bpf.c:(.text+0x88f): undefined reference to `secure_getenv'
m_bpf.o: In function `parse_bpf':
m_bpf.c:(.text+0x587): undefined reference to `secure_getenv'
collect2: error: ld returned 1 exit status

There is no special reason to use the secure version of getenv, thus let's
simply use getenv().

CC: Daniel Borkmann <daniel@iogearbox.net>
Fixes: 88eea5395483 ("tc: {f,m}_bpf: allow to retrieve uds path from env")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
---

v2: rework the fix to use getenv() instead of secure_getenv()

 examples/bpf/bpf_agent.c | 2 +-
 tc/f_bpf.c               | 2 +-
 tc/m_bpf.c               | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/examples/bpf/bpf_agent.c b/examples/bpf/bpf_agent.c
index 426b8800bf4e..f9b9ce3ccb3d 100644
--- a/examples/bpf/bpf_agent.c
+++ b/examples/bpf/bpf_agent.c
@@ -154,7 +154,7 @@ static void bpf_map_get_from_env(int *tfd)
 		memset(key, 0, sizeof(key));
 		snprintf(key, sizeof(key), "BPF_MAP%d", i);
 
-		val = secure_getenv(key);
+		val = getenv(key);
 		assert(val != NULL);
 
 		tfd[i] = atoi(val);
diff --git a/tc/f_bpf.c b/tc/f_bpf.c
index c21bf33fd25f..490dc6b4e7ba 100644
--- a/tc/f_bpf.c
+++ b/tc/f_bpf.c
@@ -122,7 +122,7 @@ opt_bpf:
 
 			NEXT_ARG();
 			if (ebpf) {
-				bpf_uds_name = secure_getenv(BPF_ENV_UDS);
+				bpf_uds_name = getenv(BPF_ENV_UDS);
 				bpf_obj = *argv;
 				NEXT_ARG();
 
diff --git a/tc/m_bpf.c b/tc/m_bpf.c
index 9ddb6672693c..c51f44fc6ce6 100644
--- a/tc/m_bpf.c
+++ b/tc/m_bpf.c
@@ -105,7 +105,7 @@ opt_bpf:
 
 			NEXT_ARG();
 			if (ebpf) {
-				bpf_uds_name = secure_getenv(BPF_ENV_UDS);
+				bpf_uds_name = getenv(BPF_ENV_UDS);
 				bpf_obj = *argv;
 				NEXT_ARG();
 
-- 
2.4.2

Re: [PATCH v2 iproute2] tc: fix bpf compilation with old glibc

[Daniel Borkmann]

On 07/23/2015 09:17 AM, Nicolas Dichtel wrote:
> Error was:
> f_bpf.o: In function `bpf_parse_opt':
> f_bpf.c:(.text+0x88f): undefined reference to `secure_getenv'
> m_bpf.o: In function `parse_bpf':
> m_bpf.c:(.text+0x587): undefined reference to `secure_getenv'
> collect2: error: ld returned 1 exit status
>
> There is no special reason to use the secure version of getenv, thus let's
> simply use getenv().
>
> CC: Daniel Borkmann <daniel@iogearbox.net>
> Fixes: 88eea5395483 ("tc: {f,m}_bpf: allow to retrieve uds path from env")
> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>

Acked-by: Daniel Borkmann <daniel@iogearbox.net>

Re: [PATCH v2 iproute2] tc: fix bpf compilation with old glibc

[Alexei Starovoitov]

On Thu, Jul 23, 2015 at 09:17:41AM +0200, Nicolas Dichtel wrote:
> Error was:
> f_bpf.o: In function `bpf_parse_opt':
> f_bpf.c:(.text+0x88f): undefined reference to `secure_getenv'
> m_bpf.o: In function `parse_bpf':
> m_bpf.c:(.text+0x587): undefined reference to `secure_getenv'
> collect2: error: ld returned 1 exit status
> 
> There is no special reason to use the secure version of getenv, thus let's
> simply use getenv().
> 
> CC: Daniel Borkmann <daniel@iogearbox.net>
> Fixes: 88eea5395483 ("tc: {f,m}_bpf: allow to retrieve uds path from env")
> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
> ---
> 
> v2: rework the fix to use getenv() instead of secure_getenv()

had the same workaround locally.
Acked-by: Alexei Starovoitov <ast@plumgrid.com>

Re: [PATCH v2 iproute2] tc: fix bpf compilation with old glibc

[Yegor Yefremov]

On Thu, Jul 23, 2015 at 11:50 PM, Alexei Starovoitov
<alexei.starovoitov@gmail.com> wrote:
> On Thu, Jul 23, 2015 at 09:17:41AM +0200, Nicolas Dichtel wrote:
>> Error was:
>> f_bpf.o: In function `bpf_parse_opt':
>> f_bpf.c:(.text+0x88f): undefined reference to `secure_getenv'
>> m_bpf.o: In function `parse_bpf':
>> m_bpf.c:(.text+0x587): undefined reference to `secure_getenv'
>> collect2: error: ld returned 1 exit status
>>
>> There is no special reason to use the secure version of getenv, thus let's
>> simply use getenv().
>>
>> CC: Daniel Borkmann <daniel@iogearbox.net>
>> Fixes: 88eea5395483 ("tc: {f,m}_bpf: allow to retrieve uds path from env")
>> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
>> ---
>>
>> v2: rework the fix to use getenv() instead of secure_getenv()
>
> had the same workaround locally.
> Acked-by: Alexei Starovoitov <ast@plumgrid.com>

Tested-by: Yegor Yefremov <yegorslists@googlemail.com>

tested with uclibc, that has problems with secure_getenv() too.

Yegor

Re: [PATCH iproute2] tc: fix bpf compilation with old glibc

[Stephen Hemminger]

On Wed, 22 Jul 2015 14:29:30 +0200
Nicolas Dichtel <nicolas.dichtel@6wind.com> wrote:

> Error was:
> f_bpf.o: In function `bpf_parse_opt':
> f_bpf.c:(.text+0x88f): undefined reference to `secure_getenv'
> m_bpf.o: In function `parse_bpf':
> m_bpf.c:(.text+0x587): undefined reference to `secure_getenv'
> collect2: error: ld returned 1 exit status
> 
> CC: Daniel Borkmann <daniel@iogearbox.net>
> Fixes: 88eea5395483 ("tc: {f,m}_bpf: allow to retrieve uds path from env")
> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>

Applied thanks.