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Fix __ASSUME_ACCEPT4 issues (bug 16609).

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In <https://sourceware.org/ml/libc-alpha/2013-12/msg00008.html>,
Aurelien noted issues with the definition of __ASSUME_ACCEPT4, which I
discussed in more detail in
<https://sourceware.org/ml/libc-alpha/2013-12/msg00014.html>; these
are now bug 16609.

As previously noted, __ASSUME_ACCEPT4 is used in two ways:

* In OS-independent code, to mean "accept4 can be assumed to work
  rather than fail with ENOSYS".  It doesn't matter whether it's
  implemented with socketcall or a separate syscall.

* In Linux-specific code, to mean "the socketcall multiplex syscall
  can be assumed to handle the accept4 operation.  When used in
  Linux-specific code, it *never* refers to anything relating to the
  accept4 syscall, only to the socketcall multiplexer.

This patch splits the macro into separate __ASSUME_ACCEPT4_SOCKETCALL,
__ASSUME_ACCEPT4_SYSCALL and __ASSUME_ACCEPT4 to clarify the different
cases involved.  A macro __ASSUME_SOCKETCALL is added for convenience
in writing logic relating to all socketcall architectures.  In
addition, to address the issue of architectures where socketcall
support for accept4 was added before a separate syscall was added (and
so the separate syscall should not be used unless known to be present
or fallback to socketcall is available), a fourth macro
__ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL is added to indicate that the
syscall became available at the same time as socketcall support.  This
is then used in the relevant places in a conditional determining
whether to undefine __NR_accept4 (the simple approach to avoiding the
syscall's presence causing problems; I didn't try to implement runtime
fallback from the syscall to socketcall).

Architecture-specific note: alpha defined __ASSUME_ACCEPT4 for 2.6.33
and later, but actually the syscall was added for alpha in 3.2, so
this patch uses the correct condition for __ASSUME_ACCEPT4_SYSCALL
there.

Tested x86_64, including that disassembly of the installed shared
libraries is unchanged by this patch.

	[BZ #16609]
	* sysdeps/unix/sysv/linux/kernel-features.h [__i386__ ||
	__powerpc__ || __s390__ || __sh__ || __sparc__]
	(__ASSUME_SOCKETCALL): Define.
	[__LINUX_KERNEL_VERSION && __ASSUME_SOCKETCALL]
	(__ASSUME_ACCEPT4_SOCKETCALL): Likewise.
	[(__LINUX_KERNEL_VERSION >= 0x02061c && (__x86_64__ || __sparc__))
	|| (__LINUX_KERNEL_VERSION >= 0x020625 && (__powerpc__ ||
	__sh__))] (__ASSUME_ACCEPT4_SYSCALL): Likewise.
	[__sparc__] (__ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL): Likewise.
	[__ASSUME_ACCEPT4_SOCKETCALL || __ASSUME_ACCEPT4_SYSCALL]
	(__ASSUME_ACCEPT4): Define instead of using previous
	[__LINUX_KERNEL_VERSION >= 0x02061c && (__i386__ || __x86_64__ ||
	__powerpc__ || __sparc__ || __s390__)] condition.
	* sysdeps/unix/sysv/linux/aarch64/kernel-features.h
	(__ASSUME_ACCEPT4): Change to __ASSUME_ACCEPT4_SYSCALL.
	* sysdeps/unix/sysv/linux/accept4.c [__ASSUME_SOCKETCALL &&
	!__ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL &&
	!__ASSUME_ACCEPT4_SYSCALL] (__NR_accept4): Undefine.
	[!__ASSUME_ACCEPT4]: Change condition to
	[!__ASSUME_ACCEPT4_SOCKETCALL].
	* sysdeps/unix/sysv/linux/alpha/kernel-features.h
	(__ASSUME_ACCEPT4): Change to __ASSUME_ACCEPT4_SYSCALL.  Correct
	condition to [__LINUX_KERNEL_VERSION >= 0x030200].
	* sysdeps/unix/sysv/linux/arm/kernel-features.h
	[__LINUX_KERNEL_VERSION >= 0x020624] (__ASSUME_ACCEPT4): Change to
	__ASSUME_ACCEPT4_SYSCALL.
	* sysdeps/unix/sysv/linux/i386/accept4.S [__ASSUME_ACCEPT4]:
	Change conditions to [__ASSUME_ACCEPT4_SOCKETCALL].
	* sysdeps/unix/sysv/linux/ia64/kernel-features.h
	[__LINUX_KERNEL_VERSION >= 0x030300] (__ASSUME_ACCEPT4): Change to
	__ASSUME_ACCEPT4_SYSCALL.
	* sysdeps/unix/sysv/linux/internal_accept4.S [__ASSUME_SOCKETCALL
	&& !__ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL &&
	!__ASSUME_ACCEPT4_SYSCALL] (__NR_accept4): Undefine.
	[__ASSUME_ACCEPT4]: Change condition to
	[__ASSUME_ACCEPT4_SOCKETCALL].
	* sysdeps/unix/sysv/linux/m68k/kernel-features.h
	(__ASSUME_SOCKETCALL): Define.
	[__LINUX_KERNEL_VERSION >= 0x02061c] (__ASSUME_ACCEPT4): Remove.
	* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
	(__ASSUME_SOCKETCALL): Define.
	(__ASSUME_ACCEPT4): Remove.
	[__LINUX_KERNEL_VERSION >= 0x020621] (__ASSUME_ACCEPT4_SYSCALL):
	Define.
	* sysdeps/unix/sysv/linux/mips/kernel-features.h
	[__LINUX_KERNEL_VERSION >= 0x02061f] (__ASSUME_ACCEPT4_SYSCALL):
	Likewise.
	* sysdeps/unix/sysv/linux/tile/kernel-features.h
	(__ASSUME_ACCEPT4): Change to __ASSUME_ACCEPT4_SYSCALL.

	* sysdeps/unix/sysv/linux/hppa/kernel-features.h
	[__LINUX_KERNEL_VERSION >= 0x020622] (__ASSUME_ACCEPT4_SYSCALL):
	Define.
This commit is contained in:
Joseph Myers
2014-02-20 17:50:31 +00:00
parent 5d7b57cad5
commit dd481ccffd
16 changed files with 151 additions and 23 deletions
Download Patch File Download Diff File Expand all files Collapse all files

51
ChangeLog
View File

@ -1,5 +1,56 @@
2014-02-20 Joseph Myers <joseph@codesourcery.com>
[BZ #16609]
* sysdeps/unix/sysv/linux/kernel-features.h [__i386__ ||
__powerpc__ || __s390__ || __sh__ || __sparc__]
(__ASSUME_SOCKETCALL): Define.
[__LINUX_KERNEL_VERSION && __ASSUME_SOCKETCALL]
(__ASSUME_ACCEPT4_SOCKETCALL): Likewise.
[(__LINUX_KERNEL_VERSION >= 0x02061c && (__x86_64__ || __sparc__))
|| (__LINUX_KERNEL_VERSION >= 0x020625 && (__powerpc__ ||
__sh__))] (__ASSUME_ACCEPT4_SYSCALL): Likewise.
[__sparc__] (__ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL): Likewise.
[__ASSUME_ACCEPT4_SOCKETCALL || __ASSUME_ACCEPT4_SYSCALL]
(__ASSUME_ACCEPT4): Define instead of using previous
[__LINUX_KERNEL_VERSION >= 0x02061c && (__i386__ || __x86_64__ ||
__powerpc__ || __sparc__ || __s390__)] condition.
* sysdeps/unix/sysv/linux/aarch64/kernel-features.h
(__ASSUME_ACCEPT4): Change to __ASSUME_ACCEPT4_SYSCALL.
* sysdeps/unix/sysv/linux/accept4.c [__ASSUME_SOCKETCALL &&
!__ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL &&
!__ASSUME_ACCEPT4_SYSCALL] (__NR_accept4): Undefine.
[!__ASSUME_ACCEPT4]: Change condition to
[!__ASSUME_ACCEPT4_SOCKETCALL].
* sysdeps/unix/sysv/linux/alpha/kernel-features.h
(__ASSUME_ACCEPT4): Change to __ASSUME_ACCEPT4_SYSCALL. Correct
condition to [__LINUX_KERNEL_VERSION >= 0x030200].
* sysdeps/unix/sysv/linux/arm/kernel-features.h
[__LINUX_KERNEL_VERSION >= 0x020624] (__ASSUME_ACCEPT4): Change to
__ASSUME_ACCEPT4_SYSCALL.
* sysdeps/unix/sysv/linux/i386/accept4.S [__ASSUME_ACCEPT4]:
Change conditions to [__ASSUME_ACCEPT4_SOCKETCALL].
* sysdeps/unix/sysv/linux/ia64/kernel-features.h
[__LINUX_KERNEL_VERSION >= 0x030300] (__ASSUME_ACCEPT4): Change to
__ASSUME_ACCEPT4_SYSCALL.
* sysdeps/unix/sysv/linux/internal_accept4.S [__ASSUME_SOCKETCALL
&& !__ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL &&
!__ASSUME_ACCEPT4_SYSCALL] (__NR_accept4): Undefine.
[__ASSUME_ACCEPT4]: Change condition to
[__ASSUME_ACCEPT4_SOCKETCALL].
* sysdeps/unix/sysv/linux/m68k/kernel-features.h
(__ASSUME_SOCKETCALL): Define.
[__LINUX_KERNEL_VERSION >= 0x02061c] (__ASSUME_ACCEPT4): Remove.
* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
(__ASSUME_SOCKETCALL): Define.
(__ASSUME_ACCEPT4): Remove.
[__LINUX_KERNEL_VERSION >= 0x020621] (__ASSUME_ACCEPT4_SYSCALL):
Define.
* sysdeps/unix/sysv/linux/mips/kernel-features.h
[__LINUX_KERNEL_VERSION >= 0x02061f] (__ASSUME_ACCEPT4_SYSCALL):
Likewise.
* sysdeps/unix/sysv/linux/tile/kernel-features.h
(__ASSUME_ACCEPT4): Change to __ASSUME_ACCEPT4_SYSCALL.
* sysdeps/unix/sysv/linux/arm/bits/hwcap.h (HWCAP_ARM_VFPD32): New
macro.
(HWCAP_ARM_LPAE): Likewise.

2
NEWS
View File

@ -9,7 +9,7 @@ Version 2.20
* The following bugs are resolved with this release:
15894, 16447, 16545, 16574.
15894, 16447, 16545, 16574, 16609.
* The am33 port, which had not worked for several years, has been removed
from ports.

7
ports/ChangeLog.hppa
View File

@ -1,3 +1,10 @@
2014-02-20 Joseph Myers <joseph@codesourcery.com>
[BZ #16609]
* sysdeps/unix/sysv/linux/hppa/kernel-features.h
[__LINUX_KERNEL_VERSION >= 0x020622] (__ASSUME_ACCEPT4_SYSCALL):
Define.
2014-02-12 Joseph Myers <joseph@codesourcery.com>
* sysdeps/unix/sysv/linux/hppa/bits/mman.h [__USE_BSD]: Change

5
ports/sysdeps/unix/sysv/linux/hppa/kernel-features.h
View File

@ -30,4 +30,9 @@
/* PA-RISC 2.6.9 kernels had the first LWS CAS support */
#define __ASSUME_LWS_CAS 1
/* Support for the accept4 syscall was added in 2.6.34. */
#if __LINUX_KERNEL_VERSION >= 0x020622
# define __ASSUME_ACCEPT4_SYSCALL 1
#endif
#include_next <kernel-features.h>

2
sysdeps/unix/sysv/linux/aarch64/kernel-features.h
View File

@ -24,7 +24,7 @@
/* AArch64 support starts with 3.7.0, guaranteeing many kernel
features. */
#define __ASSUME_ACCEPT4 1
#define __ASSUME_ACCEPT4_SYSCALL 1
#define __ASSUME_DUP3 1
#define __ASSUME_EVENTFD2 1
#define __ASSUME_IN_NONBLOCK 1

13
sysdeps/unix/sysv/linux/accept4.c
View File

@ -24,6 +24,14 @@
#include <sys/syscall.h>
#include <kernel-features.h>
/* Do not use the accept4 syscall on socketcall architectures unless
it was added at the same time as the socketcall support or can be
assumed to be present. */
#if defined __ASSUME_SOCKETCALL \
&& !defined __ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL \
&& !defined __ASSUME_ACCEPT4_SYSCALL
# undef __NR_accept4
#endif
#ifdef __NR_accept4
int
@ -42,7 +50,7 @@ accept4 (int fd, __SOCKADDR_ARG addr, socklen_t *addr_len, int flags)
return result;
}
#elif defined __NR_socketcall
# ifndef __ASSUME_ACCEPT4
# ifndef __ASSUME_ACCEPT4_SOCKETCALL
extern int __internal_accept4 (int fd, __SOCKADDR_ARG addr,
socklen_t *addr_len, int flags)
attribute_hidden;
@ -83,7 +91,8 @@ accept4 (int fd, __SOCKADDR_ARG addr, socklen_t *addr_len, int flags)
return -1;
}
# else
/* When __ASSUME_ACCEPT4 accept4 is defined in internal_accept4.S. */
/* When __ASSUME_ACCEPT4_SOCKETCALL accept4 is defined in
internal_accept4.S. */
# endif
#else
int

6
sysdeps/unix/sysv/linux/alpha/kernel-features.h
View File

@ -42,9 +42,9 @@
# define __ASSUME_SIGNALFD4 1
#endif
/* Support for accept4 was added for alpha after 2.6.33-rc1. */
#if __LINUX_KERNEL_VERSION >= 0x020621
# define __ASSUME_ACCEPT4 1
/* Support for accept4 was added for alpha in 3.2. */
#if __LINUX_KERNEL_VERSION >= 0x030200
# define __ASSUME_ACCEPT4_SYSCALL 1
#endif
#include_next <kernel-features.h>

2
sysdeps/unix/sysv/linux/arm/kernel-features.h
View File

@ -33,7 +33,7 @@
/* Support for the accept4 syscall was added in 2.6.36. */
#if __LINUX_KERNEL_VERSION >= 0x020624
# define __ASSUME_ACCEPT4 1
# define __ASSUME_ACCEPT4_SYSCALL 1
#endif
#include_next <kernel-features.h>

4
sysdeps/unix/sysv/linux/i386/accept4.S
View File

@ -23,7 +23,7 @@
#define EINVAL 22
#define ENOSYS 38
#ifdef __ASSUME_ACCEPT4
#ifdef __ASSUME_ACCEPT4_SOCKETCALL
# define errlabel SYSCALL_ERROR_LABEL
#else
# define errlabel .Lerr
@ -114,7 +114,7 @@ ENTRY (__libc_accept4)
ret
#endif
#ifndef __ASSUME_ACCEPT4
#ifndef __ASSUME_ACCEPT4_SOCKETCALL
/* The kernel returns -EINVAL for unknown socket operations.
We need to convert that error to an ENOSYS error. */
.Lerr: cmpl $-EINVAL, %eax

2
sysdeps/unix/sysv/linux/ia64/kernel-features.h
View File

@ -49,7 +49,7 @@
/* Support for the accept4 syscall was added in 3.3. */
#if __LINUX_KERNEL_VERSION >= 0x030300
# define __ASSUME_ACCEPT4 1
# define __ASSUME_ACCEPT4_SYSCALL 1
#endif
#include_next <kernel-features.h>

12
sysdeps/unix/sysv/linux/internal_accept4.S
View File

@ -1,8 +1,18 @@
#include <kernel-features.h>
#include <sys/syscall.h>
/* Do not use the accept4 syscall on socketcall architectures unless
it was added at the same time as the socketcall support or can be
assumed to be present. */
#if defined __ASSUME_SOCKETCALL \
&& !defined __ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL \
&& !defined __ASSUME_ACCEPT4_SYSCALL
# undef __NR_accept4
#endif
#if !defined __NR_accept4 && defined __NR_socketcall
# define socket accept4
# ifdef __ASSUME_ACCEPT4
# ifdef __ASSUME_ACCEPT4_SOCKETCALL
# define __socket accept4
# else
# define __socket __internal_accept4

44
sysdeps/unix/sysv/linux/kernel-features.h
View File

@ -40,6 +40,18 @@
/* The sendfile syscall was introduced in 2.2.0. */
#define __ASSUME_SENDFILE 1
/* Some architectures use the socketcall multiplexer for some or all
socket-related operations, via a socket.S file in glibc, instead of
separate syscalls. __ASSUME_SOCKETCALL is defined for such
architectures. */
#if defined __i386__ \
|| defined __powerpc__ \
|| defined __s390__ \
|| defined __sh__ \
|| defined __sparc__
# define __ASSUME_SOCKETCALL 1
#endif
/* Linux 2.3.39 introduced IPC64. Except for powerpc. Linux 2.4.0 on
PPC introduced a correct IPC64. But PowerPC64 does not support a
separate 64-bit syscall, already 64-bit. */
@ -164,10 +176,34 @@
# define __ASSUME_DUP3 1
#endif
/* Support for the accept4 syscall was added in 2.6.28. */
#if __LINUX_KERNEL_VERSION >= 0x02061c \
&& (defined __i386__ || defined __x86_64__ || defined __powerpc__ \
|| defined __sparc__ || defined __s390__)
/* Support for accept4 functionality was added in 2.6.28, but for some
architectures using a separate syscall rather than socketcall that
syscall was only added later, and some architectures first had
socketcall support then a separate syscall. Define
__ASSUME_ACCEPT4_SOCKETCALL if glibc uses socketcall on this
architecture and accept4 is available through socketcall,
__ASSUME_ACCEPT4_SYSCALL if it is available through a separate
syscall, __ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL if it became
available through a separate syscall at the same time as through
socketcall, and __ASSUME_ACCEPT4 if the accept4 function is known
to work. */
#if __LINUX_KERNEL_VERSION >= 0x02061c && defined __ASSUME_SOCKETCALL
# define __ASSUME_ACCEPT4_SOCKETCALL 1
#endif
/* The accept4 syscall was added for x86_64 and SPARC in 2.6.28, and
for PowerPC and SH in 2.6.37. */
#if (__LINUX_KERNEL_VERSION >= 0x02061c \
&& (defined __x86_64__ || defined __sparc__)) \
|| (__LINUX_KERNEL_VERSION >= 0x020625 \
&& (defined __powerpc__ || defined __sh__))
# define __ASSUME_ACCEPT4_SYSCALL 1
#endif
#ifdef __sparc__
# define __ASSUME_ACCEPT4_SYSCALL_WITH_SOCKETCALL 1
#endif
#if defined __ASSUME_ACCEPT4_SOCKETCALL || defined __ASSUME_ACCEPT4_SYSCALL
# define __ASSUME_ACCEPT4 1
#endif

8
sysdeps/unix/sysv/linux/m68k/kernel-features.h
View File

@ -17,6 +17,9 @@
License along with the GNU C Library. If not, see
<http://www.gnu.org/licenses/>. */
/* m68k uses socketcall. */
#define __ASSUME_SOCKETCALL 1
/* Many syscalls were added in 2.6.10 for m68k. */
#define __ASSUME_UTIMES 1
@ -35,11 +38,6 @@
# define __ASSUME_DUP3 1
#endif
/* Support for the accept4 syscall was added in 2.6.28. */
#if __LINUX_KERNEL_VERSION >= 0x02061c
# define __ASSUME_ACCEPT4 1
#endif
#include_next <kernel-features.h>
/* These syscalls were added only in 3.0 for m68k. */

9
sysdeps/unix/sysv/linux/microblaze/kernel-features.h
View File

@ -16,6 +16,9 @@
<http://www.gnu.org/licenses/>. */
/* MicroBlaze uses socketcall. */
#define __ASSUME_SOCKETCALL 1
/* MicroBlaze glibc support starts with 2.6.30, guaranteeing many kernel features. */
#define __ASSUME_UTIMES 1
#define __ASSUME_O_CLOEXEC 1
@ -24,7 +27,11 @@
#define __ASSUME_PIPE2 1
#define __ASSUME_EVENTFD2 1
#define __ASSUME_SIGNALFD4 1
#define __ASSUME_ACCEPT4 1
#define __ASSUME_DUP3 1
/* Support for the accept4 syscall was added in 2.6.33. */
#if __LINUX_KERNEL_VERSION >= 0x020621
# define __ASSUME_ACCEPT4_SYSCALL 1
#endif
#include_next <kernel-features.h>

5
sysdeps/unix/sysv/linux/mips/kernel-features.h
View File

@ -31,6 +31,11 @@
# define __ASSUME_SIGNALFD4 1
#endif
/* Support for the accept4 syscall was added in 2.6.31. */
#if __LINUX_KERNEL_VERSION >= 0x02061f
# define __ASSUME_ACCEPT4_SYSCALL 1
#endif
#include_next <kernel-features.h>
/* The n32 syscall ABI did not have a getdents64 syscall until

2
sysdeps/unix/sysv/linux/tile/kernel-features.h
View File

@ -25,7 +25,7 @@
#define __ASSUME_PIPE2 1
#define __ASSUME_EVENTFD2 1
#define __ASSUME_SIGNALFD4 1
#define __ASSUME_ACCEPT4 1
#define __ASSUME_ACCEPT4_SYSCALL 1
#define __ASSUME_DUP3 1
#include_next <kernel-features.h>