Commit Graph

12 Commits

Author SHA1 Message Date
Hauke Mehrtens
da360299b6 uapi/if_ether.h: move __UAPI_DEF_ETHHDR libc define
This fixes a compile problem of some user space applications by not
including linux/libc-compat.h in uapi/if_ether.h.

linux/libc-compat.h checks which "features" the header files, included
from the libc, provide to make the Linux kernel uapi header files only
provide no conflicting structures and enums. If a user application mixes
kernel headers and libc headers it could happen that linux/libc-compat.h
gets included too early where not all other libc headers are included
yet. Then the linux/libc-compat.h would not prevent all the
redefinitions and we run into compile problems.
This patch removes the include of linux/libc-compat.h from
uapi/if_ether.h to fix the recently introduced case, but not all as this
is more or less impossible.

It is no problem to do the check directly in the if_ether.h file and not
in libc-compat.h as this does not need any fancy glibc header detection
as glibc never provided struct ethhdr and should define
__UAPI_DEF_ETHHDR by them self when they will provide this.

The following test program did not compile correctly any more:

#include <linux/if_ether.h>
#include <netinet/in.h>
#include <linux/in.h>

int main(void)
{
	return 0;
}

Fixes: 6926e041a8 ("uapi/if_ether.h: prevent redefinition of struct ethhdr")
Reported-by: Guillaume Nault <g.nault@alphalink.fr>
Cc: <stable@vger.kernel.org> # 4.15
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-13 11:23:24 -05:00
Hauke Mehrtens
6926e041a8 uapi/if_ether.h: prevent redefinition of struct ethhdr
Musl provides its own ethhdr struct definition. Add a guard to prevent
its definition of the appropriate musl header has already been included.

glibc does not implement this header, but when glibc will implement this
they can just define __UAPI_DEF_ETHHDR 0 to make it work with the
kernel.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-04 14:30:52 -05:00
Felix Janda
c0bace7984 uapi libc compat: add fallback for unsupported libcs
libc-compat.h aims to prevent symbol collisions between uapi and libc
headers for each supported libc. This requires continuous coordination
between them.

The goal of this commit is to improve the situation for libcs (such as
musl) which are not yet supported and/or do not wish to be explicitly
supported, while not affecting supported libcs. More precisely, with
this commit, unsupported libcs can request the suppression of any
specific uapi definition by defining the correspondings _UAPI_DEF_*
macro as 0. This can fix symbol collisions for them, as long as the
libc headers are included before the uapi headers. Inclusion in the
other order is outside the scope of this commit.

All infrastructure in order to enable this fallback for unsupported
libcs is already in place, except that libc-compat.h unconditionally
defines all _UAPI_DEF_* macros to 1 for all unsupported libcs so that
any previous definitions are ignored. In order to fix this, this commit
merely makes these definitions conditional.

This commit together with the musl libc commit

http://git.musl-libc.org/cgit/musl/commit/?id=04983f2272382af92eb8f8838964ff944fbb8258

fixes for example the following compiler errors when <linux/in6.h> is
included after musl's <netinet/in.h>:

./linux/in6.h:32:8: error: redefinition of 'struct in6_addr'
./linux/in6.h:49:8: error: redefinition of 'struct sockaddr_in6'
./linux/in6.h:59:8: error: redefinition of 'struct ipv6_mreq'

The comments referencing glibc are still correct, but this file is not
only used for glibc any more.

Signed-off-by: Felix Janda <felix.janda@posteo.de>
Reviewed-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-03 10:52:47 -05:00
Greg Kroah-Hartman
6f52b16c5b License cleanup: add SPDX license identifier to uapi header files with no license
Many user space API headers are missing licensing information, which
makes it hard for compliance tools to determine the correct license.

By default are files without license information under the default
license of the kernel, which is GPLV2.  Marking them GPLV2 would exclude
them from being included in non GPLV2 code, which is obviously not
intended. The user space API headers fall under the syscall exception
which is in the kernels COPYING file:

   NOTE! This copyright does *not* cover user programs that use kernel
   services by normal system calls - this is merely considered normal use
   of the kernel, and does *not* fall under the heading of "derived work".

otherwise syscall usage would not be possible.

Update the files which contain no license information with an SPDX
license identifier.  The chosen identifier is 'GPL-2.0 WITH
Linux-syscall-note' which is the officially assigned identifier for the
Linux syscall exception.  SPDX license identifiers are a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.  See the previous patch in this series for the
methodology of how this patch was researched.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:19:54 +01:00
Mikko Rapeli
53dc65d4d3 include/uapi/linux/ipx.h: fix conflicting defitions with glibc netipx/ipx.h
Fixes these compiler warnings via libc-compat.h when glibc netipx/ipx.h is
included before linux/ipx.h:

./linux/ipx.h:9:8: error: redefinition of ‘struct sockaddr_ipx’
./linux/ipx.h:26:8: error: redefinition of ‘struct ipx_route_definition’
./linux/ipx.h:32:8: error: redefinition of ‘struct ipx_interface_definition’
./linux/ipx.h:49:8: error: redefinition of ‘struct ipx_config_data’
./linux/ipx.h:58:8: error: redefinition of ‘struct ipx_route_def’

Signed-off-by: Mikko Rapeli <mikko.rapeli@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-22 16:25:15 -07:00
Nicolas Dichtel
f0a3fdca79 uapi glibc compat: fix compilation when !__USE_MISC in glibc
These structures are defined only if __USE_MISC is set in glibc net/if.h
headers, ie when _BSD_SOURCE or _SVID_SOURCE are defined.

CC: Jan Engelhardt <jengelh@inai.de>
CC: Josh Boyer <jwboyer@fedoraproject.org>
CC: Stephen Hemminger <shemming@brocade.com>
CC: Waldemar Brodkorb <mail@waldemar-brodkorb.de>
CC: Gabriel Laskar <gabriel@lse.epita.fr>
CC: Mikko Rapeli <mikko.rapeli@iki.fi>
Fixes: 4a91cb61bb ("uapi glibc compat: fix compile errors when glibc net/if.h included before linux/if.h")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-20 19:57:22 -04:00
Mikko Rapeli
4a91cb61bb uapi glibc compat: fix compile errors when glibc net/if.h included before linux/if.h
glibc's net/if.h contains copies of definitions from linux/if.h and these
conflict and cause build failures if both files are included by application
source code. Changes in uapi headers, which fixed header file dependencies to
include linux/if.h when it was needed, e.g. commit 1ffad83d, made the
net/if.h and linux/if.h incompatibilities visible as build failures for
userspace applications like iproute2 and xtables-addons.

This patch fixes compile errors when glibc net/if.h is included before
linux/if.h:

./linux/if.h:99:21: error: redeclaration of enumerator ‘IFF_NOARP’
./linux/if.h:98:23: error: redeclaration of enumerator ‘IFF_RUNNING’
./linux/if.h:97:26: error: redeclaration of enumerator ‘IFF_NOTRAILERS’
./linux/if.h:96:27: error: redeclaration of enumerator ‘IFF_POINTOPOINT’
./linux/if.h:95:24: error: redeclaration of enumerator ‘IFF_LOOPBACK’
./linux/if.h:94:21: error: redeclaration of enumerator ‘IFF_DEBUG’
./linux/if.h:93:25: error: redeclaration of enumerator ‘IFF_BROADCAST’
./linux/if.h:92:19: error: redeclaration of enumerator ‘IFF_UP’
./linux/if.h:252:8: error: redefinition of ‘struct ifconf’
./linux/if.h:203:8: error: redefinition of ‘struct ifreq’
./linux/if.h:169:8: error: redefinition of ‘struct ifmap’
./linux/if.h:107:23: error: redeclaration of enumerator ‘IFF_DYNAMIC’
./linux/if.h:106:25: error: redeclaration of enumerator ‘IFF_AUTOMEDIA’
./linux/if.h:105:23: error: redeclaration of enumerator ‘IFF_PORTSEL’
./linux/if.h:104:25: error: redeclaration of enumerator ‘IFF_MULTICAST’
./linux/if.h:103:21: error: redeclaration of enumerator ‘IFF_SLAVE’
./linux/if.h:102:22: error: redeclaration of enumerator ‘IFF_MASTER’
./linux/if.h:101:24: error: redeclaration of enumerator ‘IFF_ALLMULTI’
./linux/if.h💯23: error: redeclaration of enumerator ‘IFF_PROMISC’

The cases where linux/if.h is included before net/if.h need a similar fix in
the glibc side, or the order of include files can be changed userspace
code as a workaround.

This change was tested in x86 userspace on Debian unstable with
scripts/headers_compile_test.sh:

$ make headers_install && \
  cd usr/include && ../../scripts/headers_compile_test.sh -l -k
...
cc -Wall -c -nostdinc -I /usr/lib/gcc/i586-linux-gnu/5/include -I /usr/lib/gcc/i586-linux-gnu/5/include-fixed -I . -I /home/mcfrisk/src/linux-2.6/usr/headers_compile_test_include.2uX2zH -I /home/mcfrisk/src/linux-2.6/usr/headers_compile_test_include.2uX2zH/i586-linux-gnu -o /dev/null ./linux/if.h_libc_before_kernel.h
PASSED libc before kernel test: ./linux/if.h

Reported-by: Jan Engelhardt <jengelh@inai.de>
Reported-by: Josh Boyer <jwboyer@fedoraproject.org>
Reported-by: Stephen Hemminger <shemming@brocade.com>
Reported-by: Waldemar Brodkorb <mail@waldemar-brodkorb.de>
Cc: Gabriel Laskar <gabriel@lse.epita.fr>
Signed-off-by: Mikko Rapeli <mikko.rapeli@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-09 21:29:31 -04:00
Stephen Hemminger
279c6c7fa6 api: fix compatibility of linux/in.h with netinet/in.h
u
This fixes breakage to iproute2 build with recent kernel headers
caused by:
   commit a263653ed7
   Author: Pablo Neira Ayuso <pablo@netfilter.org>
   Date:   Wed Jun 17 10:28:27 2015 -0500

   netfilter: don't pull include/linux/netfilter.h from netns headers

The issue is that definitions in linux/in.h overlap with those
in netinet/in.h. This patch solves this by introducing the same
mechanism as was used to solve the same problem with linux/in6.h

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-29 18:56:21 -07:00
WANG Cong
3b50d90298 ipv6: fix redefinition of in6_pktinfo and ip6_mtuinfo
Both netinet/in.h and linux/ipv6.h define these two structs,
if we include both of them, we got:

	/usr/include/linux/ipv6.h:19:8: error: redefinition of ‘struct in6_pktinfo’
	 struct in6_pktinfo {
		^
	In file included from /usr/include/arpa/inet.h:22:0,
			 from txtimestamp.c:33:
	/usr/include/netinet/in.h:524:8: note: originally defined here
	 struct in6_pktinfo
		^
	In file included from txtimestamp.c:40:0:
	/usr/include/linux/ipv6.h:24:8: error: redefinition of ‘struct ip6_mtuinfo’
	 struct ip6_mtuinfo {
		^
	In file included from /usr/include/arpa/inet.h:22:0,
			 from txtimestamp.c:33:
	/usr/include/netinet/in.h:531:8: note: originally defined here
	 struct ip6_mtuinfo
		^
So similarly to what we did for in6_addr, we need to sync with
libc header on their definitions.

Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-08 19:29:11 -08:00
stephen hemminger
6d08acd2d3 in6: fix conflict with glibc
Resolve conflicts between glibc definition of IPV6 socket options
and those defined in Linux headers. Looks like earlier efforts to
solve this did not cover all the definitions.

It resolves warnings during iproute2 build.
Please consider for stable as well.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-22 16:12:36 -05:00
Serge Hallyn
ea1a8217b0 xattr: guard against simultaneous glibc header inclusion
If the glibc xattr.h header is included after the uapi header,
compilation fails due to an enum re-using a #define from the uapi
header.

Protect against this by guarding the define and enum inclusions against
each other.

(See https://lists.debian.org/debian-glibc/2014/03/msg00029.html
and https://sourceware.org/glibc/wiki/Synchronizing_Headers
for more information.)

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Allan McRae <allan@archlinux.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:21:06 -07:00
Carlos O'Donell
cfd280c912 net: sync some IP headers with glibc
Solution:
=========

- Synchronize linux's `include/uapi/linux/in6.h'
  with glibc's `inet/netinet/in.h'.
- Synchronize glibc's `inet/netinet/in.h with linux's
  `include/uapi/linux/in6.h'.
- Allow including the headers in either other.
- First header included defines the structures and macros.

Details:
========

The kernel promises not to break the UAPI ABI so I don't
see why we can't just have the two userspace headers
coordinate?

If you include the kernel headers first you get those,
and if you include the glibc headers first you get those,
and the following patch arranges a coordination and
synchronization between the two.

Let's handle `include/uapi/linux/in6.h' from linux,
and `inet/netinet/in.h' from glibc and ensure they compile
in any order and preserve the required ABI.

These two patches pass the following compile tests:

cat >> test1.c <<EOF
int main (void) {
  return 0;
}
EOF
gcc -c test1.c

cat >> test2.c <<EOF
int main (void) {
  return 0;
}
EOF
gcc -c test2.c

One wrinkle is that the kernel has a different name for one of
the members in ipv6_mreq. In the kernel patch we create a macro
to cover the uses of the old name, and while that's not entirely
clean it's one of the best solutions (aside from an anonymous
union which has other issues).

I've reviewed the code and it looks to me like the ABI is
assured and everything matches on both sides.

Notes:
- You want netinet/in.h to include bits/in.h as early as possible,
  but it needs in_addr so define in_addr early.
- You want bits/in.h included as early as possible so you can use
  the linux specific code to define __USE_KERNEL_DEFS based on
  the _UAPI_* macro definition and use those to cull in.h.
- glibc was missing IPPROTO_MH, added here.

Compile tested and inspected.

Reported-by: Thomas Backlund <tmb@mageia.org>
Cc: Thomas Backlund <tmb@mageia.org>
Cc: libc-alpha@sourceware.org
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Cc: David S. Miller <davem@davemloft.net>
Tested-by: Cong Wang <amwang@redhat.com>
Signed-off-by: Carlos O'Donell <carlos@redhat.com>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-04 13:12:43 -04:00