On Sun, Apr 24, 2016 at 11:45 AM, Mikko Rapeli <mikko.rapeli@xxxxxx> wrote: > 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:100:23: 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@xxxxxxx> > Reported-by: Josh Boyer <jwboyer@xxxxxxxxxxxxxxxxx> > Reported-by: Stephen Hemminger <shemming@xxxxxxxxxxx> > Reported-by: Waldemar Brodkorb <mail@xxxxxxxxxxxxxxxxxxxx> > Cc: Gabriel Laskar <gabriel@xxxxxxxxxxxx> > Signed-off-by: Mikko Rapeli <mikko.rapeli@xxxxxx> Bump. Did this get lost in a queue somewhere? josh > --- > include/uapi/linux/if.h | 28 +++++++++++++++++++++++++ > include/uapi/linux/libc-compat.h | 44 ++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 72 insertions(+) > > v1: > http://marc.info/?l=linux-kernel&m=145485386721798&w=2 > > v2: > Added handling for net_device_flags IFF_LOWER_UP, IFF_DORMANT and IFF_ECHO > which are unknown to glibc as suggested by David Miller in > http://marc.info/?l=linux-kernel&m=145650410726228&w=2 > > diff --git a/include/uapi/linux/if.h b/include/uapi/linux/if.h > index f802775..e601c8c 100644 > --- a/include/uapi/linux/if.h > +++ b/include/uapi/linux/if.h > @@ -19,14 +19,20 @@ > #ifndef _LINUX_IF_H > #define _LINUX_IF_H > > +#include <linux/libc-compat.h> /* for compatibility with glibc */ > #include <linux/types.h> /* for "__kernel_caddr_t" et al */ > #include <linux/socket.h> /* for "struct sockaddr" et al */ > #include <linux/compiler.h> /* for "__user" et al */ > > +#if __UAPI_DEF_IF_IFNAMSIZ > #define IFNAMSIZ 16 > +#endif /* __UAPI_DEF_IF_IFNAMSIZ */ > #define IFALIASZ 256 > #include <linux/hdlc/ioctl.h> > > +/* For glibc compatibility. An empty enum does not compile. */ > +#if __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO != 0 && \ > + __UAPI_DEF_IF_NET_DEVICE_FLAGS != 0 > /** > * enum net_device_flags - &struct net_device flags > * > @@ -68,6 +74,8 @@ > * @IFF_ECHO: echo sent packets. Volatile. > */ > enum net_device_flags { > +/* for compatibility with glibc net/if.h */ > +#if __UAPI_DEF_IF_NET_DEVICE_FLAGS > IFF_UP = 1<<0, /* sysfs */ > IFF_BROADCAST = 1<<1, /* volatile */ > IFF_DEBUG = 1<<2, /* sysfs */ > @@ -84,11 +92,17 @@ enum net_device_flags { > IFF_PORTSEL = 1<<13, /* sysfs */ > IFF_AUTOMEDIA = 1<<14, /* sysfs */ > IFF_DYNAMIC = 1<<15, /* sysfs */ > +#endif /* __UAPI_DEF_IF_NET_DEVICE_FLAGS */ > +#if __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO > IFF_LOWER_UP = 1<<16, /* volatile */ > IFF_DORMANT = 1<<17, /* volatile */ > IFF_ECHO = 1<<18, /* volatile */ > +#endif /* __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO */ > }; > +#endif /* __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO != 0 && __UAPI_DEF_IF_NET_DEVICE_FLAGS != 0 */ > > +/* for compatibility with glibc net/if.h */ > +#if __UAPI_DEF_IF_NET_DEVICE_FLAGS > #define IFF_UP IFF_UP > #define IFF_BROADCAST IFF_BROADCAST > #define IFF_DEBUG IFF_DEBUG > @@ -105,9 +119,13 @@ enum net_device_flags { > #define IFF_PORTSEL IFF_PORTSEL > #define IFF_AUTOMEDIA IFF_AUTOMEDIA > #define IFF_DYNAMIC IFF_DYNAMIC > +#endif /* __UAPI_DEF_IF_NET_DEVICE_FLAGS */ > + > +#if __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO > #define IFF_LOWER_UP IFF_LOWER_UP > #define IFF_DORMANT IFF_DORMANT > #define IFF_ECHO IFF_ECHO > +#endif /* __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO */ > > #define IFF_VOLATILE (IFF_LOOPBACK|IFF_POINTOPOINT|IFF_BROADCAST|IFF_ECHO|\ > IFF_MASTER|IFF_SLAVE|IFF_RUNNING|IFF_LOWER_UP|IFF_DORMANT) > @@ -166,6 +184,8 @@ enum { > * being very small might be worth keeping for clean configuration. > */ > > +/* for compatibility with glibc net/if.h */ > +#if __UAPI_DEF_IF_IFMAP > struct ifmap { > unsigned long mem_start; > unsigned long mem_end; > @@ -175,6 +195,7 @@ struct ifmap { > unsigned char port; > /* 3 bytes spare */ > }; > +#endif /* __UAPI_DEF_IF_IFMAP */ > > struct if_settings { > unsigned int type; /* Type of physical device or protocol */ > @@ -200,6 +221,8 @@ struct if_settings { > * remainder may be interface specific. > */ > > +/* for compatibility with glibc net/if.h */ > +#if __UAPI_DEF_IF_IFREQ > struct ifreq { > #define IFHWADDRLEN 6 > union > @@ -223,6 +246,7 @@ struct ifreq { > struct if_settings ifru_settings; > } ifr_ifru; > }; > +#endif /* __UAPI_DEF_IF_IFREQ */ > > #define ifr_name ifr_ifrn.ifrn_name /* interface name */ > #define ifr_hwaddr ifr_ifru.ifru_hwaddr /* MAC address */ > @@ -249,6 +273,8 @@ struct ifreq { > * must know all networks accessible). > */ > > +/* for compatibility with glibc net/if.h */ > +#if __UAPI_DEF_IF_IFCONF > struct ifconf { > int ifc_len; /* size of buffer */ > union { > @@ -256,6 +282,8 @@ struct ifconf { > struct ifreq __user *ifcu_req; > } ifc_ifcu; > }; > +#endif /* __UAPI_DEF_IF_IFCONF */ > + > #define ifc_buf ifc_ifcu.ifcu_buf /* buffer address */ > #define ifc_req ifc_ifcu.ifcu_req /* array of structures */ > > diff --git a/include/uapi/linux/libc-compat.h b/include/uapi/linux/libc-compat.h > index 7d024ce..d5e38c7 100644 > --- a/include/uapi/linux/libc-compat.h > +++ b/include/uapi/linux/libc-compat.h > @@ -51,6 +51,40 @@ > /* We have included glibc headers... */ > #if defined(__GLIBC__) > > +/* Coordinate with glibc net/if.h header. */ > +#if defined(_NET_IF_H) > + > +/* GLIBC headers included first so don't define anything > + * that would already be defined. */ > + > +#define __UAPI_DEF_IF_IFCONF 0 > +#define __UAPI_DEF_IF_IFMAP 0 > +#define __UAPI_DEF_IF_IFNAMSIZ 0 > +#define __UAPI_DEF_IF_IFREQ 0 > +/* Everything up to IFF_DYNAMIC, matches net/if.h until glibc 2.23 */ > +#define __UAPI_DEF_IF_NET_DEVICE_FLAGS 0 > +/* For the future if glibc adds IFF_LOWER_UP, IFF_DORMANT and IFF_ECHO */ > +#ifndef __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO > +#define __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO 1 > +#endif /* __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO */ > + > +#else /* _NET_IF_H */ > + > +/* Linux headers included first, and we must define everything > + * we need. The expectation is that glibc will check the > + * __UAPI_DEF_* defines and adjust appropriately. */ > + > +#define __UAPI_DEF_IF_IFCONF 1 > +#define __UAPI_DEF_IF_IFMAP 1 > +#define __UAPI_DEF_IF_IFNAMSIZ 1 > +#define __UAPI_DEF_IF_IFREQ 1 > +/* Everything up to IFF_DYNAMIC, matches net/if.h until glibc 2.23 */ > +#define __UAPI_DEF_IF_NET_DEVICE_FLAGS 1 > +/* For the future if glibc adds IFF_LOWER_UP, IFF_DORMANT and IFF_ECHO */ > +#define __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO 1 > + > +#endif /* _NET_IF_H */ > + > /* Coordinate with glibc netinet/in.h header. */ > #if defined(_NETINET_IN_H) > > @@ -117,6 +151,16 @@ > * that we need. */ > #else /* !defined(__GLIBC__) */ > > +/* Definitions for if.h */ > +#define __UAPI_DEF_IF_IFCONF 1 > +#define __UAPI_DEF_IF_IFMAP 1 > +#define __UAPI_DEF_IF_IFNAMSIZ 1 > +#define __UAPI_DEF_IF_IFREQ 1 > +/* Everything up to IFF_DYNAMIC, matches net/if.h until glibc 2.23 */ > +#define __UAPI_DEF_IF_NET_DEVICE_FLAGS 1 > +/* For the future if glibc adds IFF_LOWER_UP, IFF_DORMANT and IFF_ECHO */ > +#define __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO 1 > + > /* Definitions for in.h */ > #define __UAPI_DEF_IN_ADDR 1 > #define __UAPI_DEF_IN_IPPROTO 1 > -- > 2.8.0.rc3 > -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
