Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Convert machine/elf.h, machine/frame.h, machine/sigframe.h,
machine/signal.h and machine/ucontext.h into common x86 includes,
copying from amd64 and merging with i386.

Kernel-only compat definitions are kept in the i386/include/sigframe.h
and i386/include/signal.h, to reduce amd64 kernel namespace pollution.
The amd64 compat uses its own definitions so far.

The _MACHINE_ELF_WANT_32BIT definition is to allow the
sys/boot/userboot/userboot/elf32_freebsd.c to use i386 ELF definitions
on the amd64 compile host. The same hack could be usefully abused by
other code too.

Reserve AT_TIMEKEEP auxv entry for providing usermode the pointer to
timekeeping information.

MFC after: 1 week

Add AT_STACKPROT elf aux vector. Will be used to inform rtld about the
initial stack protection set by the kernel image activator.

Supply some useful information to the started image using ELF aux vectors.
In particular, provide pagesize and pagesizes array, the canary value
for SSP use, number of host CPUs and osreldate.

Tested by: marius (sparc64)
MFC after: 1 month

Define architectural load bases for PIE binaries. Addresses were selected
by looking at the bases used for non-relocatable executables by gnu ld(1),
and adjusting it slightly.

Discussed with: bz
Reviewed by: kan
Tested by: bz (i386, amd64), bsam (linux)
MFC after: some time

Add AT_EXECPATH ELF auxinfo entry type. The value's a_ptr is a pointer
to the full path of the image that is being executed.
Increase AT_COUNT.

Remove no longer true comment about types used in Linux ELF binaries,
listed types contain FreeBSD-specific entries.

Reviewed by: kan

AT_DEBUG and AT_BRK were OBE like 10 years ago, so retire them.

Reviewed by: peter

PR:
Submitted by:
Reviewed by:
Approved by:
Obtained from:
MFC after:
Security:
Move the relocation definitions to the common elf header so that DTrace
can use them on one architecture targeted to a different one.

Add the additional ELF types defines in Sun's "Linker and Libraries"
manual.

Add definitions for TLS relocations.

Add sysentvec->sv_fixlimits() hook so that we can catch cases on 64 bit
systems where the data/stack/etc limits are too big for a 32 bit process.

Move the 5 or so identical instances of ELF_RTLD_ADDR() into imgact_elf.c.

Supply an ia32_fixlimits function. Export the clip/default values to
sysctl under the compat.ia32 heirarchy.

Have mmap(0, ...) respect the current p->p_limits[RLIMIT_DATA].rlim_max
value rather than the sysctl tweakable variable. This allows mmap to
place mappings at sensible locations when limits have been reduced.

Have the imgact_elf.c ld-elf.so.1 placement algorithm use the same
method as mmap(0, ...) now does.

Note that we cannot remove all references to the sysctl tweakable
maxdsiz etc variables because /etc/login.conf specifies a datasize
of 'unlimited'. And that causes exec etc to fail since it can no
longer find space to mmap things.

Hack to enable getting two different elf32 and elf64 loaders in the
same i386 loader binary.

Move the definition of ElfN_Hashelt to common headers. The only platform
which has a different definition for this is alpha.

Make MAXTSIZ, DFLDSIZ, MAXDSIZ, DFLSSIZ, MAXSSIZ, SGROWSIZ loader
tunable.

Reviewed by: peter
MFC after: 2 weeks

Use a machine dependent type, Elf_Hashelt, for the elements of the elf
dynamic symbol table buckets and chains. The sparc64 toolchain uses 32
bit .hash entries, unlike other 64 bits architectures (alpha), which use
64 bit entries.

Discussed with: dfr, jdp

Fix style of defines.

Change #ifdef KERNEL to #ifdef _KERNEL in the public headers. "KERNEL"
is an application space macro and the applications are supposed to be free
to use it as they please (but cannot). This is consistant with the other
BSD's who made this change quite some time ago. More commits to come.

$Id$ -> $FreeBSD$

On the i386, load the ELF dynamic linker where an mmap(0, ...) would
put it, just like on the Alpha. It was wrong to load it at the
fixed address 0x08000000. That should only be done if the dynamic
linker is an executable (not a shared object) with a specific load
address encoded in the object file itself.

This fixes the recent breakage in the Linux emulator.

Change the load address of the ELF dynamic linker from "2L*MAXDSIZ"
to an architecture-specific value defined in <machine/elf.h>. This
solves problems on large-memory systems that have a high value for
MAXDSIZ.

The load address is controlled by a new macro ELF_RTLD_ADDR(vmspace).
On the i386 it is hard-wired to 0x08000000, which is the standard
SVR4 location for the dynamic linker.

On the Alpha, the dynamic linker is loaded MAXDSIZ bytes beyond
the start of the program's data segment. This is the same place
a userland mmap(0, ...) call would put it, so it ends up just below
all the shared libraries. The rationale behind the calculation is
that it allows room for the data segment to grow to its maximum
possible size.

These changes have been tested on the i386 for several months
without problems. They have been tested on the Alpha as well,
though not for nearly as long. I would like to merge the changes
into 3.1 within a week if no problems have surfaced as a result of
them.

Add an ELF_MACHINE_OK() macro for compatability with the Alpha version.

Add generic defines ELF_ARCH, ELF_CLASS, and ELF_DATA. These give
the relevant characteristics of the native machine, for building
and checking Elf_Ehdr structures.

Add structures to represent ELF "note" headers. Add defines for the
note types used in ELF core files.

Revamp the ELF include files to better support architecture-independent
applications. Here's how it works.

The kernel should include <machine/elf.h> to get the definitions
for the native architecture. It can reference the various ELF
structures with generic names like Elf_Sym, Elf_Shdr, etc. A define
__ELF_WORD_SIZE is also available with the value 32 or 64 as
appropriate for the native architecture.

Generic applications should include <elf.h>, which is just a wrapper
for <machine/elf.h>.

Applications such as object file dumpers that need to deal with
foreign ELF files can include <sys/elf32.h> and/or <sys/elf64.h>.
Both can be included from the same source file if desired. The
structure names must be referenced using wordsize-specific names
like Elf32_Sym, Elf64_Shdr, etc.

I haven't change the alpha stuff, but I haven't broken it either.

Define some machine characteristics using symbol naming on conventions
in place in the other BSD's.

Fill out the ELF header files to make them more or less complete.
Fix a macro name that was misspelled both in brandelf.c and
imgact_elf.h.