Support and use mixed compat/non-compat aliases in syscalls.list
diff mbox

Message ID Pine.LNX.4.64.1409240931100.7800@digraph.polyomino.org.uk
State New
Headers show

Commit Message

Joseph Myers Sept. 24, 2014, 9:33 a.m. UTC
This patch, relative to a tree with
<https://sourceware.org/ml/libc-alpha/2014-09/msg00546.html> (pending
review) applied, enables syscalls.list entries to specify both compat
and non-compat symbol versions for the same syscall definition, making
use of this for setrlimit / chown / lchown where the inability to
specify such aliases showed up in the course of work on bug 14138.

The change to make-syscalls.sh is minimal: adding a SHARED conditional
on the compat_symbol calls.  It remains the case that if a compat
symbol version is specified, the syscall is only built for the shared
library at all if an explicit symbol version is given for a non-compat
symbol (so it's necessary to specify "lchown@@GLIBC_2.0
chown@GLIBC_2.0" rather than just "lchown chown@GLIBC_2.0").  It also
remains the case, as already commented in make-syscalls.sh, that no
SHLIB_COMPAT conditionals are generated, so there would be problems if
the same syscalls.list file, with compat symbols, were used for both
configurations that should have those symbols and configurations for
which they should be conditioned out with SHLIB_COMPAT.

Tested for x86.

2014-09-24  Joseph Myers  <joseph@codesourcery.com>

	* sysdeps/unix/make-syscalls.sh (emit_weak_aliases): Condition
	compat_symbol calls on [SHARED].
	* sysdeps/unix/sysv/linux/i386/chown.c: Remove file.
	* sysdeps/unix/sysv/linux/powerpc/lchown.S: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/chown.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/syscalls.list (newchown): Change to
	chown.
	(lchown): Specify symbol version for lchown alias.  Add
	chown@GLIBC_2.0 alias.
	(oldsetrlimit): Remove.
	(setrlimit): Add setrlimit@GLIBC_2.0 alias.
	* sysdeps/unix/sysv/linux/m68k/m680x0/syscalls.list
	(oldsetrlimit): Remove.
	(setrlimit): Add setrlimit@GLIBC_2.0 alias.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/syscalls.list
	(lchown): New syscall entry.
	(oldsetrlimit): Remove.
	(setrlimit): Add setrlimit@GLIBC_2.0 alias.
	* sysdeps/unix/sysv/linux/s390/s390-32/syscalls.list (newchown):
	Change to chown.
	(lchown): Specify symbol version for lchown alias.  Add
	chown@GLIBC_2.0 alias.
	(oldsetrlimit): Remove.
	(setrlimit): Add setrlimit@GLIBC_2.0 alias.

Comments

Joseph Myers Sept. 30, 2014, 2:42 p.m. UTC | #1
Ping.  This patch 
<https://sourceware.org/ml/libc-alpha/2014-09/msg00559.html> is pending 
review.
Roland McGrath Oct. 1, 2014, 8:26 p.m. UTC | #2
I have not thought about it very deeply, but this seems OK to me.

Patch
diff mbox

diff --git a/sysdeps/unix/make-syscalls.sh b/sysdeps/unix/make-syscalls.sh
index 6eba62c..fd6ebb4 100644
--- a/sysdeps/unix/make-syscalls.sh
+++ b/sysdeps/unix/make-syscalls.sh
@@ -113,7 +113,7 @@  emit_weak_aliases()
       *@*)
 	base=`echo $name | sed 's/@.*//'`
 	ver=`echo $name | sed 's/.*@//;s/\./_/g'`
-	echo "	 echo '#ifndef NOT_IN_libc'; \\"
+	echo "	 echo '#if defined SHARED && !defined NOT_IN_libc'; \\"
 	if test -z "$vcount" ; then
 	  source=$strong
 	  vcount=1
diff --git a/sysdeps/unix/sysv/linux/i386/chown.c b/sysdeps/unix/sysv/linux/i386/chown.c
deleted file mode 100644
index b46b80e..0000000
--- a/sysdeps/unix/sysv/linux/i386/chown.c
+++ /dev/null
@@ -1,53 +0,0 @@ 
-/* Copyright (C) 1998-2014 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-#include <errno.h>
-#include <unistd.h>
-
-#include <sysdep.h>
-#include <sys/syscall.h>
-#include <shlib-compat.h>
-
-#include <linux/posix_types.h>
-
-/*
-  In Linux 2.1.x the chown functions have been changed.  A new function lchown
-  was introduced.  The new chown now follows symlinks - the old chown and the
-  new lchown do not follow symlinks.
-  The new lchown function has the same number as the old chown had and the
-  new chown has a new number.  When compiling with headers from Linux > 2.1.8x
-  it's impossible to run this libc with older kernels.  In these cases libc
-  has therefore to route calls to chown to the old chown function.
-*/
-
-extern int __chown_is_lchown (const char *__file, uid_t __owner,
-			      gid_t __group);
-
-
-#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
-/* Compiling for compatibility.  */
-int
-attribute_compat_text_section
-__chown_is_lchown (const char *file, uid_t owner, gid_t group)
-{
-  return __lchown (file, owner, group);
-}
-#endif
-
-#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
-compat_symbol (libc, __chown_is_lchown, chown, GLIBC_2_0);
-#endif
diff --git a/sysdeps/unix/sysv/linux/i386/syscalls.list b/sysdeps/unix/sysv/linux/i386/syscalls.list
index bcd9d74..db375a8 100644
--- a/sysdeps/unix/sysv/linux/i386/syscalls.list
+++ b/sysdeps/unix/sysv/linux/i386/syscalls.list
@@ -1,15 +1,14 @@ 
 # File name	Caller	Syscall name	Args	Strong name	Weak names
 
-newchown	EXTRA	chown32		i:sii	__chown		chown@@GLIBC_2.1
-lchown		-	lchown32	i:sii	__lchown	lchown
+chown		-	chown32		i:sii	__chown		chown@@GLIBC_2.1
+lchown		-	lchown32	i:sii	__lchown	lchown@@GLIBC_2.0 chown@GLIBC_2.0
 fchown		-	fchown32	i:iii	__fchown	fchown
 
 modify_ldt	EXTRA	modify_ldt	i:ipi	__modify_ldt	modify_ldt
 vm86old		EXTRA	vm86old		i:p	__vm86old	vm86@GLIBC_2.0
 vm86		-	vm86		i:ip	__vm86		vm86@@GLIBC_2.3.4
 oldgetrlimit	EXTRA	getrlimit	i:ip	__old_getrlimit	getrlimit@GLIBC_2.0
-oldsetrlimit	EXTRA	setrlimit	i:ip	__old_setrlimit	setrlimit@GLIBC_2.0
-setrlimit	-	setrlimit	i:ip	__setrlimit	setrlimit@@GLIBC_2.2
+setrlimit	-	setrlimit	i:ip	__setrlimit	setrlimit@GLIBC_2.0 setrlimit@@GLIBC_2.2
 waitpid		-	waitpid		Ci:ipi	__waitpid	waitpid	__libc_waitpid
 
 prlimit64	EXTRA	prlimit64	i:iipp	prlimit64
diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/syscalls.list b/sysdeps/unix/sysv/linux/m68k/m680x0/syscalls.list
index 6f10536..b0ad689 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/syscalls.list
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/syscalls.list
@@ -1,5 +1,4 @@ 
 # File name	Caller	Syscall name	Args	Strong name	Weak names
 
 oldgetrlimit	EXTRA	getrlimit	i:ip	__old_getrlimit	getrlimit@GLIBC_2.0
-oldsetrlimit	EXTRA	setrlimit	i:ip	__old_setrlimit	setrlimit@GLIBC_2.0
-setrlimit	-	setrlimit	i:ip	__setrlimit	setrlimit@@GLIBC_2.2
+setrlimit	-	setrlimit	i:ip	__setrlimit	setrlimit@GLIBC_2.0 setrlimit@@GLIBC_2.2
diff --git a/sysdeps/unix/sysv/linux/powerpc/lchown.S b/sysdeps/unix/sysv/linux/powerpc/lchown.S
deleted file mode 100644
index 1785748..0000000
--- a/sysdeps/unix/sysv/linux/powerpc/lchown.S
+++ /dev/null
@@ -1,38 +0,0 @@ 
-/* lchown system call.
-   Copyright (C) 1998-2014 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-/* Some old kernel headers call lchown() 'chown'.  The number is
-   the same.  */
-
-#include <sysdep.h>
-
-#ifdef __NR_lchown
-	PSEUDO (__lchown, lchown, 3)
-#else
-	PSEUDO (__lchown, chown, 3)
-#endif
-	ret
-	PSEUDO_END(__lchown)
-	weak_alias (__lchown, lchown)
-
-#ifdef SHARED
-#include <shlib-compat.h>
-# if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
-compat_symbol (libc, __lchown, chown, GLIBC_2_0)
-# endif
-#endif
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/syscalls.list b/sysdeps/unix/sysv/linux/powerpc/powerpc32/syscalls.list
index 25487cc..451d508 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/syscalls.list
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/syscalls.list
@@ -1,11 +1,11 @@ 
 # File name	Caller	Syscall name	# args	Strong name	Weak names
 
 chown		-	chown		i:sii	__chown		chown@@GLIBC_2.1
+lchown		-	lchown		i:sii	__lchown	lchown@@GLIBC_2.0 chown@GLIBC_2.0
 
 # System calls with wrappers.
 oldgetrlimit	EXTRA	getrlimit	i:ip	__old_getrlimit	getrlimit@GLIBC_2.0
-oldsetrlimit	EXTRA	setrlimit	i:ip	__old_setrlimit	setrlimit@GLIBC_2.0
-setrlimit	-	setrlimit	i:ip	__setrlimit	setrlimit@@GLIBC_2.2
+setrlimit	-	setrlimit	i:ip	__setrlimit	setrlimit@GLIBC_2.0 setrlimit@@GLIBC_2.2
 
 # Due to 64bit alignment there is a dummy second parameter
 readahead	-	readahead	i:iiiii	__readahead	readahead
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/chown.c b/sysdeps/unix/sysv/linux/s390/s390-32/chown.c
deleted file mode 100644
index d1e3aa4..0000000
--- a/sysdeps/unix/sysv/linux/s390/s390-32/chown.c
+++ /dev/null
@@ -1,54 +0,0 @@ 
-/* Copyright (C) 2000-2014 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, see
-   <http://www.gnu.org/licenses/>.  */
-
-#include <errno.h>
-#include <unistd.h>
-
-#include <sysdep.h>
-#include <sys/syscall.h>
-#include <shlib-compat.h>
-
-#include <linux/posix_types.h>
-
-/*
-  In Linux 2.1.x the chown functions have been changed.  A new function lchown
-  was introduced.  The new chown now follows symlinks - the old chown and the
-  new lchown do not follow symlinks.
-  The new lchown function has the same number as the old chown had and the
-  new chown has a new number.  When compiling with headers from Linux > 2.1.8x
-  it's impossible to run this libc with older kernels.  In these cases libc
-  has therefore to route calls to chown to the old chown function.
-*/
-
-/* Running under Linux > 2.1.80.  */
-
-
-#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
-/* Compiling for compatibility.  */
-int
-attribute_compat_text_section
-__chown_is_lchown (const char *file, uid_t owner, gid_t group)
-{
-  return __lchown (file, owner, group);
-}
-#endif
-
-#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
-strong_alias (__chown_is_lchown, _chown_is_lchown)
-compat_symbol (libc, __chown_is_lchown, __chown, GLIBC_2_0);
-compat_symbol (libc, _chown_is_lchown, chown, GLIBC_2_0);
-#endif
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/syscalls.list b/sysdeps/unix/sysv/linux/s390/s390-32/syscalls.list
index 3126c60..7a6015a 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/syscalls.list
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/syscalls.list
@@ -1,12 +1,11 @@ 
 # File name	Caller	Syscall name	Args	Strong name	Weak names
 
-newchown	EXTRA	chown32		i:sii	__chown		chown@@GLIBC_2.1
-lchown		-	lchown32	i:sii	__lchown	lchown
+chown		-	chown32		i:sii	__chown		chown@@GLIBC_2.1
+lchown		-	lchown32	i:sii	__lchown	lchown@@GLIBC_2.0 chown@GLIBC_2.0
 fchown		-	fchown32	i:iii	__fchown	fchown
 
 oldgetrlimit	EXTRA	getrlimit	i:ip	__old_getrlimit	getrlimit@GLIBC_2.0
-oldsetrlimit	EXTRA	setrlimit	i:ip	__old_setrlimit	setrlimit@GLIBC_2.0
-setrlimit	-	setrlimit	i:ip	__setrlimit	setrlimit@@GLIBC_2.2
+setrlimit	-	setrlimit	i:ip	__setrlimit	setrlimit@GLIBC_2.0 setrlimit@@GLIBC_2.2
 
 prlimit64	EXTRA	prlimit64	i:iipp	prlimit64
 fanotify_mark	EXTRA	fanotify_mark	i:iiiiis	fanotify_mark