06 Jan, 2021
4 commits
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not defined by any architecture (and never had been)
Signed-off-by: Al Viro
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It's not used anywhere downstream (and never had been, AFAICS).
Theoretically, fs/binfmt_elf.c does use it, but only in the
non-regset coredump handling and all biarch architectures
end up with that ifdefed out.Signed-off-by: Al Viro
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To get rid of hardcoded size/offset in those macros we need to have
a definition of i386 variant of struct elf_prstatus. However, we can't
do that in asm/compat.h - the types needed for that are not there and
adding an include of asm/user32.h into asm/compat.h would cause a lot
of mess.That could be conveniently done in elfcore-compat.h, but currently there
is nowhere to put arch-dependent parts of it - no asm/elfcore-compat.h.
So we introduce a new file (asm/elfcore-compat.h, present on architectures
that have CONFIG_ARCH_HAS_ELFCORE_COMPAT set, currently only on x86),
have it pulled by linux/elfcore-compat.h and move the definitions there.As a side benefit, we don't need to worry about accidental inclusion of
that file into binfmt_elf.c itself, so we don't need the dance with
COMPAT_PRSTATUS_SIZE, etc. - only fs/compat_binfmt_elf.c will see
that header.Signed-off-by: Al Viro
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Preparations to doing i386 compat elf_prstatus sanely - rather than duplicating
the beginning of compat_elf_prstatus, take these fields into a separate
structure (compat_elf_prstatus_common), so that it could be reused. Due to
the incestous relationship between binfmt_elf.c and compat_binfmt_elf.c we
need the same shape change done to native struct elf_prstatus, gathering the
fields prior to pr_reg into a new structure (struct elf_prstatus_common).Fortunately, offset of pr_reg is always a multiple of 16 with no padding
right before it, so it's possible to turn all the stuff prior to it into
a single member without disturbing the layout.[build fix from Geert Uytterhoeven folded in]
Signed-off-by: Al Viro
05 Jan, 2021
1 commit
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On 64bit architectures that support 32bit processes there are
two possible layouts for NT_PRSTATUS note in ELF coredumps.
For one thing, several fields are 64bit for native processes
and 32bit for compat ones (pr_sigpend, etc.). For another,
the register dump is obviously different - the size and number
of registers are not going to be the same for 32bit and 64bit
variants of processor.Usually that's handled by having two structures - elf_prstatus
for native layout and compat_elf_prstatus for 32bit one.
32bit processes are handled by fs/compat_binfmt_elf.c, which
defines a macro called 'elf_prstatus' that expands to compat_elf_prstatus.
Then it includes fs/binfmt_elf.c, which makes all references to
struct elf_prstatus to be textually replaced with struct
compat_elf_prstatus. Ugly and somewhat brittle, but it works.However, amd64 is worse - there are _three_ possible layouts.
One for native 64bit processes, another for i386 (32bit) processes
and yet another for x32 (32bit address space with full 64bit
registers).Both i386 and x32 processes are handled by fs/compat_binfmt_elf.c,
with usual compat_binfmt_elf.c trickery. However, the layouts
for i386 and x32 are not identical - they have the common beginning,
but the register dump part (pr_reg) is bigger on x32. Worse, pr_reg
is not the last field - it's followed by int pr_fpvalid, so that
field ends up at different offsets for i386 and x32 layouts.Fortunately, there's not much code that cares about any of that -
it's all encapsulated in fill_thread_core_info(). Since x32
variant is bigger, we define compat_elf_prstatus to match that
layout. That way i386 processes have enough space to fit
their layout into.Moreover, since these layouts are identical prior to pr_reg,
we don't need to distinguish x32 and i386 cases when we are
setting the fields prior to pr_reg.Filling pr_reg itself is done by calling ->get() method of
appropriate regset, and that method knows what layout (and size)
to use.We do need to distinguish x32 and i386 cases only for two
things: setting ->pr_fpvalid (offset differs for x32 and
i386) and choosing the right size for our note.The way it's done is Not Nice, for the lack of more accurate
printable description. There are two macros (PRSTATUS_SIZE and
SET_PR_FPVALID), that default essentially to sizeof(struct elf_prstatus)
and (S)->pr_fpvalid = 1. On x86 asm/compat.h provides its own
variants.Unfortunately, quite a few things go wrong there:
* PRSTATUS_SIZE doesn't use the normal test for process
being an x32 one; it compares the size reported by regset with
the size of pr_reg.
* it hardcodes the sizes of x32 and i386 variants (296 and 144
resp.), so if some change in includes leads to asm/compat.h pulled
in by fs/binfmt_elf.c we are in trouble - it will end up using
the size of x32 variant for 64bit processes.
* it's in the wrong place; asm/compat.h couldn't define
the structure for i386 layout, since it lacks quite a few types
needed for it. Hardcoded sizes are largely due to that.The proper fix would be to have an explicitly defined i386 variant
of structure and have PRSTATUS_SIZE/SET_PR_FPVALID check for
TIF_X32 to choose the variant that should be used. Unfortunately,
that requires some manipulations of headers; we'll do that later
in the series, but for now let's go with the minimal variant -
rename PRSTATUS_SIZE in asm/compat.h to COMPAT_PRSTATUS_SIZE,
have fs/compat_binfmt_elf.c define PRSTATUS_SIZE to COMPAT_PRSTATUS_SIZE
and use the normal TIF_X32 check in that macro. The size of i386 variant
is kept hardcoded for now. Similar story for SET_PR_FPVALID.Signed-off-by: Al Viro
26 Oct, 2020
2 commits
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Like it is done for SET_PERSONALITY with ARM, which requires the ELF
header to select correct personality parameters, x86 requires the
headers when selecting which VDSO to load, instead of relying on the
going-away TIF_IA32/X32 flags.Add an indirection macro to arch_setup_additional_pages(), that x86 can
reimplement to receive the extra parameter just for ELF files. This
requires no changes to other architectures, who can continue to use the
original arch_setup_additional_pages for ELF and non-ELF binaries.Signed-off-by: Gabriel Krisman Bertazi
Signed-off-by: Thomas Gleixner
Link: https://lore.kernel.org/r/20201004032536.1229030-8-krisman@collabora.com -
Like it is done for SET_PERSONALITY with x86, which requires the ELF header
to select correct personality parameters, x86 requires the headers on
compat_start_thread() to choose starting CS for ELF32 binaries, instead of
relying on the going-away TIF_IA32/X32 flags.Add an indirection macro to ELF invocations of START_THREAD, that x86 can
reimplement to receive the extra parameter just for ELF files. This
requires no changes to other architectures who don't need the header
information, they can continue to use the original start_thread for ELF and
non-ELF binaries, and it prevents affecting non-ELF code paths for x86.Signed-off-by: Gabriel Krisman Bertazi
Signed-off-by: Thomas Gleixner
Link: https://lore.kernel.org/r/20201004032536.1229030-6-krisman@collabora.com
06 Jun, 2020
1 commit
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Pull READ_IMPLIES_EXEC changes from Borislav Petkov:
"Split the old READ_IMPLIES_EXEC workaround from executable
PT_GNU_STACK now that toolchains long support PT_GNU_STACK marking and
there's no need anymore to force modern programs into having all its
user mappings executable instead of only the stack and the PROT_EXEC
ones.Disable that automatic READ_IMPLIES_EXEC forcing on x86-64 and
arm64.Add tables documenting how READ_IMPLIES_EXEC is handled on x86-64, arm
and arm64.By Kees Cook"
* tag 'core_core_updates_for_5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
arm64/elf: Disable automatic READ_IMPLIES_EXEC for 64-bit address spaces
arm32/64/elf: Split READ_IMPLIES_EXEC from executable PT_GNU_STACK
arm32/64/elf: Add tables to document READ_IMPLIES_EXEC
x86/elf: Disable automatic READ_IMPLIES_EXEC on 64-bit
x86/elf: Split READ_IMPLIES_EXEC from executable PT_GNU_STACK
x86/elf: Add table to document READ_IMPLIES_EXEC
02 Jun, 2020
1 commit
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Pull uaccess/coredump updates from Al Viro:
"set_fs() removal in coredump-related area - mostly Christoph's
stuff..."* 'work.set_fs-exec' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
binfmt_elf_fdpic: remove the set_fs(KERNEL_DS) in elf_fdpic_core_dump
binfmt_elf: remove the set_fs(KERNEL_DS) in elf_core_dump
binfmt_elf: remove the set_fs in fill_siginfo_note
signal: refactor copy_siginfo_to_user32
powerpc/spufs: simplify spufs core dumping
powerpc/spufs: stop using access_ok
powerpc/spufs: fix copy_to_user while atomic
06 May, 2020
1 commit
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The code in binfmt_elf.c is differnt from the rest of the code that
processes siginfo, as it sends siginfo from a kernel buffer to a file
rather than from kernel memory to userspace buffers. To remove it's
use of set_fs the code needs some different siginfo helpers.Add the helper copy_siginfo_to_external to copy from the kernel's
internal siginfo layout to a buffer in the siginfo layout that
userspace expects.Modify fill_siginfo_note to use copy_siginfo_to_external instead of
set_fs and copy_siginfo_to_user.Update compat_binfmt_elf.c to use the previously added
copy_siginfo_to_external32 to handle the compat case.Signed-off-by: "Eric W. Biederman"
Signed-off-by: Christoph Hellwig
Signed-off-by: Al Viro
21 Apr, 2020
1 commit
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With arm64 64-bit environments, there should never be a need for automatic
READ_IMPLIES_EXEC, as the architecture has always been execute-bit aware
(as in, the default memory protection should be NX unless a region
explicitly requests to be executable).Suggested-by: Hector Marco-Gisbert
Signed-off-by: Kees Cook
Signed-off-by: Borislav Petkov
Reviewed-by: Jason Gunthorpe
Reviewed-by: Catalin Marinas
Link: https://lkml.kernel.org/r/20200327064820.12602-7-keescook@chromium.org
17 Mar, 2020
1 commit
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ELF program properties will be needed for detecting whether to
enable optional architecture or ABI features for a new ELF process.For now, there are no generic properties that we care about, so do
nothing unless CONFIG_ARCH_USE_GNU_PROPERTY=y.Otherwise, the presence of properties using the PT_PROGRAM_PROPERTY
phdrs entry (if any), and notify each property to the arch code.For now, the added code is not used.
Signed-off-by: Mark Brown
Signed-off-by: Dave Martin
Reviewed-by: Kees Cook
Signed-off-by: Catalin Marinas
15 Nov, 2019
1 commit
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We store elapsed time for a crashed process in struct elf_prstatus using
'timeval' structures. Once glibc starts using 64-bit time_t, this becomes
incompatible with the kernel's idea of timeval since the structure layout
no longer matches on 32-bit architectures.This changes the definition of the elf_prstatus structure to use
__kernel_old_timeval instead, which is hardcoded to the currently used
binary layout. There is no risk of overflow in y2038 though, because
the time values are all relative times, and can store up to 68 years
of process elapsed time.There is a risk of applications breaking at build time when they
use the new kernel headers and expect the type to be exactly 'timeval'
rather than a structure that has the same fields as before. Those
applications have to be modified to deal with 64-bit time_t anyway.Signed-off-by: Arnd Bergmann
31 May, 2019
1 commit
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Based on 1 normalized pattern(s):
this copyrighted material is made available to anyone wishing to use
modify copy or redistribute it subject to the terms and conditions
of the gnu general public license v 2extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 45 file(s).
Signed-off-by: Thomas Gleixner
Reviewed-by: Richard Fontana
Reviewed-by: Allison Randal
Reviewed-by: Steve Winslow
Reviewed-by: Alexios Zavras
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170027.342746075@linutronix.de
Signed-off-by: Greg Kroah-Hartman
27 Aug, 2018
1 commit
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Christoph Hellwig suggested a slightly different path for handling
backwards compatibility with the 32-bit time_t based system calls:Rather than simply reusing the compat_sys_* entry points on 32-bit
architectures unchanged, we get rid of those entry points and the
compat_time types by renaming them to something that makes more sense
on 32-bit architectures (which don't have a compat mode otherwise),
and then share the entry points under the new name with the 64-bit
architectures that use them for implementing the compatibility.The following types and interfaces are renamed here, and moved
from linux/compat_time.h to linux/time32.h:old new
--- ---
compat_time_t old_time32_t
struct compat_timeval struct old_timeval32
struct compat_timespec struct old_timespec32
struct compat_itimerspec struct old_itimerspec32
ns_to_compat_timeval() ns_to_old_timeval32()
get_compat_itimerspec64() get_old_itimerspec32()
put_compat_itimerspec64() put_old_itimerspec32()
compat_get_timespec64() get_old_timespec32()
compat_put_timespec64() put_old_timespec32()As we already have aliases in place, this patch addresses only the
instances that are relevant to the system call interface in particular,
not those that occur in device drivers and other modules. Those
will get handled separately, while providing the 64-bit version
of the respective interfaces.I'm not renaming the timex, rusage and itimerval structures, as we are
still debating what the new interface will look like, and whether we
will need a replacement at all.This also doesn't change the names of the syscall entry points, which can
be done more easily when we actually switch over the 32-bit architectures
to use them, at that point we need to change COMPAT_SYSCALL_DEFINEx to
SYSCALL_DEFINEx with a new name, e.g. with a _time32 suffix.Suggested-by: Christoph Hellwig
Link: https://lore.kernel.org/lkml/20180705222110.GA5698@infradead.org/
Signed-off-by: Arnd Bergmann
01 Feb, 2017
1 commit
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Use the new nsec based cputime accessors as part of the whole cputime
conversion from cputime_t to nsecs.Signed-off-by: Frederic Weisbecker
Cc: Benjamin Herrenschmidt
Cc: Fenghua Yu
Cc: Heiko Carstens
Cc: Linus Torvalds
Cc: Martin Schwidefsky
Cc: Michael Ellerman
Cc: Paul Mackerras
Cc: Peter Zijlstra
Cc: Rik van Riel
Cc: Stanislaw Gruszka
Cc: Thomas Gleixner
Cc: Tony Luck
Cc: Wanpeng Li
Link: http://lkml.kernel.org/r/1485832191-26889-12-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar
04 Mar, 2014
1 commit
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Add ELF_HWCAP2 to the set of auxv entries that is passed to
a 32-bit ELF program running in 32-bit compat mode under a
64-bit kernel.Signed-off-by: Ard Biesheuvel
Acked-by: Andrew Morton
Signed-off-by: Catalin Marinas
06 Oct, 2012
2 commits
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This note has the following format:
long count -- how many files are mapped
long page_size -- units for file_ofs
array of [COUNT] elements of
long start
long end
long file_ofs
followed by COUNT filenames in ASCII: "FILE1" NUL "FILE2" NUL...Signed-off-by: Denys Vlasenko
Cc: Oleg Nesterov
Cc: Amerigo Wang
Cc: "Jonathan M. Foote"
Cc: Roland McGrath
Cc: Pedro Alves
Cc: Fengguang Wu
Cc: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Existing PRSTATUS note contains only si_signo, si_code, si_errno fields
from the siginfo of the signal which caused core to be dumped.There are tools which try to analyze crashes for possible security
implications, and they want to use, among other data, si_addr field from
the SIGSEGV.This patch adds a new elf note, NT_SIGINFO, which contains the complete
siginfo_t of the signal which killed the process.Signed-off-by: Denys Vlasenko
Reviewed-by: Oleg Nesterov
Cc: Amerigo Wang
Cc: "Jonathan M. Foote"
Cc: Roland McGrath
Cc: Pedro Alves
Cc: Fengguang Wu
Cc: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Mar, 2010
1 commit
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elf_core_dump() and elf_fdpic_core_dump() use #ifdef and the corresponding
macro for hiding _multiline_ logics in functions. This patch removes
#ifdef and replaces ELF_CORE_EXTRA_* by corresponding functions. For
architectures not implemeonting ELF_CORE_EXTRA_*, we use weak functions in
order to reduce a range of modification.This cleanup is for my next patches, but I think this cleanup itself is
worth doing regardless of my firnal purpose.Signed-off-by: Daisuke HATAYAMA
Cc: "Luck, Tony"
Cc: Jeff Dike
Cc: David Howells
Cc: Greg Ungerer
Cc: Roland McGrath
Cc: Oleg Nesterov
Cc: Ingo Molnar
Cc: Alexander Viro
Cc: Andi Kleen
Cc: Alan Cox
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
30 Jan, 2008
1 commit
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This adds fs/compat_binfmt_elf.c, a wrapper around fs/binfmt_elf.c for
32-bit ELF support on 64-bit kernels. It can replace all the hand-rolled
versions of this that each 32/64 arch has, which are all about the same.To use this, an arch's asm/elf.h has to define at least a few compat_*
macros that parallel the various macros that fs/binfmt_elf.c uses for
native support.There is no attempt to deal with compat macros for the core dump format
support. To use this file, the arch has to define compat_gregset_t for
linux/elfcore-compat.h and #define CORE_DUMP_USE_REGSET. The 32-bit
compatible formats should come automatically from task_user_regset_view
called on a 32-bit task.Signed-off-by: Roland McGrath
Signed-off-by: Ingo Molnar
Signed-off-by: Thomas Gleixner
