It is the reasonable expectation that if an executable file is not
readable there will be no way for a user without special privileges to
read the file. This is enforced in ptrace_attach but if ptrace
is already attached before exec there is no enforcement for read-only
executables.
As the only way to read such an mm is through access_process_vm
spin a variant called ptrace_access_vm that will fail if the
target process is not being ptraced by the current process, or
the current process did not have sufficient privileges when ptracing
began to read the target processes mm.
In the ptrace implementations replace access_process_vm by
ptrace_access_vm. There remain several ptrace sites that still use
access_process_vm as they are reading the target executables
instructions (for kernel consumption) or register stacks. As such it
does not appear necessary to add a permission check to those calls.
This bug has always existed in Linux.
Fixes: v1.0
Cc: stable@vger.kernel.org
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This removes the 'write' argument from access_process_vm() and replaces
it with 'gup_flags' as use of this function previously silently implied
FOLL_FORCE, whereas after this patch callers explicitly pass this flag.
We make this explicit as use of FOLL_FORCE can result in surprising
behaviour (and hence bugs) within the mm subsystem.
Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Performing vma lookups without taking the mm->mmap_sem is asking for
trouble. While doing the search, the vma in question can be modified or
even removed before returning to the caller. Take the lock (shared) in
order to avoid races while iterating through the vmacache and/or rbtree.
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Cc: Steven Miao <realmz6@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Disintegrate asm/system.h for Blackfin.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: uclinux-dist-devel@blackfin.uclinux.org
Signed-off-by: Bob Liu <lliubbo@gmail.com>
Change signature of get/put_reg() according to the change of arch_ptrace()
and remove unnecessary castings.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix up the arguments to arch_ptrace() to take account of the fact that
@addr and @data are now unsigned long rather than long as of a preceding
patch in this series.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: <linux-arch@vger.kernel.org>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Flushing caches sometimes requires anomaly workarounds which require
supervisor-only insns. Normally we don't need to flush caches from
userspace so this isn't a problem, but when gcc generates trampolines
on the stack, we do.
So add a new syscall for gcc to use modeled after the mips version.
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
If an app is placing its stack in L1 scratchpad SRAM, make sure ptrace
is granted access to it so that gdb can do its thing.
Signed-off-by: Barry Song <barry.song@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
The Blackfin/FRV/SuperH guys all have the same exact FDPIC ptrace code in
their arch handlers (since they were probably copied & pasted). Since
these ptrace interfaces are an arch independent aspect of the FDPIC code,
unify them in the common ptrace code so new FDPIC ports don't need to copy
and paste this fundamental stuff yet again.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On Blackfin systems, the hardware single step exception triggers before
the system call exception, so we need to save this info to process it
later on. Otherwise, single stepping in userspace misses a few insns
right after the system call.
This is based a bit on the SuperH code added in commit 4b505db9c4.
Reported-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
We don't want to let user space modify the SYSCFG register arbitrarily as
the settings are system wide (SNEN/CNEN) and can cause misbehavior. The
only other bit here (SSSTEP) has proper controls via PTRACE_SINGLESTEP.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Use the generic ptrace_resume code for PTRACE_SYSCALL, PTRACE_CONT,
PTRACE_KILL and PTRACE_SINGLESTEP. This implies defining
arch_has_single_step in <asm/ptrace.h> and implementing the
user_enable_single_step and user_disable_single_step functions, which
also causes the breakpoint information to be cleared on fork, which
could be considered a bug fix.
Also the TIF_SYSCALL_TRACE thread flag is now cleared on PTRACE_KILL
which it previously wasn't which is consistent with all architectures
using the modern ptrace code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
These regions are either read-only and won't work anyways (bootrom), or
we don't want people screwing with them because they're shared between
all processes (fixed code).
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Commit c014e15a2f (Blackfin: convert ptrace to new memory functions)
introduced a copy & paste typo in the ptrace poke data/text handling. The
access_process_vm() function call was telling it to read instead of write.
Signed-off-by: Jie Zhang <jie.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Bill Gatliff & David Brownell pointed out we were missing some
copyrights, and licensing terms in some of the files in
./arch/blackfin, so this fixes things, and cleans them up.
It also removes:
- verbose GPL text(refer to the top level ./COPYING file)
- file names (you are looking at the file)
- bug url (it's in the ./MAINTAINERS file)
- "or later" on GPL-2, when we did not have that right
It also allows some Blackfin-specific assembly files to be under a BSD
like license (for people to use them outside of Linux).
Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
The FDPIC arches support a standard set of ptrace requests so rather than
define our own custom API, hook up those requests for common code to
leverage.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Now that we have a Blackfin memory function to figure out how to properly
access the different regions, drop the custom memory range checks in our
ptrace code and use that. It makes the code nicer and fixes bugs where
the ptrace logic wasn't handling all the different regions.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT
This will make hardirq.h inclusion cheaper for every PREEMPT=n config
(which includes allmodconfig/allyesconfig, BTW)
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use copy_to_user_page and copy_from_user_page instead of
memcpy. copy_to_user_page does cache flush when necessary.
Signed-off-by: Jie Zhang <jie.zhang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Make VMAs per mm_struct as for MMU-mode linux. This solves two problems:
(1) In SYSV SHM where nattch for a segment does not reflect the number of
shmat's (and forks) done.
(2) In mmap() where the VMA's vm_mm is set to point to the parent mm by an
exec'ing process when VM_EXECUTABLE is specified, regardless of the fact
that a VMA might be shared and already have its vm_mm assigned to another
process or a dead process.
A new struct (vm_region) is introduced to track a mapped region and to remember
the circumstances under which it may be shared and the vm_list_struct structure
is discarded as it's no longer required.
This patch makes the following additional changes:
(1) Regions are now allocated with alloc_pages() rather than kmalloc() and
with no recourse to __GFP_COMP, so the pages are not composite. Instead,
each page has a reference on it held by the region. Anything else that is
interested in such a page will have to get a reference on it to retain it.
When the pages are released due to unmapping, each page is passed to
put_page() and will be freed when the page usage count reaches zero.
(2) Excess pages are trimmed after an allocation as the allocation must be
made as a power-of-2 quantity of pages.
(3) VMAs are added to the parent MM's R/B tree and mmap lists. As an MM may
end up with overlapping VMAs within the tree, the VMA struct address is
appended to the sort key.
(4) Non-anonymous VMAs are now added to the backing inode's prio list.
(5) Holes may be punched in anonymous VMAs with munmap(), releasing parts of
the backing region. The VMA and region structs will be split if
necessary.
(6) sys_shmdt() only releases one attachment to a SYSV IPC shared memory
segment instead of all the attachments at that addresss. Multiple
shmat()'s return the same address under NOMMU-mode instead of different
virtual addresses as under MMU-mode.
(7) Core dumping for ELF-FDPIC requires fewer exceptions for NOMMU-mode.
(8) /proc/maps is now the global list of mapped regions, and may list bits
that aren't actually mapped anywhere.
(9) /proc/meminfo gains a line (tagged "MmapCopy") that indicates the amount
of RAM currently allocated by mmap to hold mappable regions that can't be
mapped directly. These are copies of the backing device or file if not
anonymous.
These changes make NOMMU mode more similar to MMU mode. The downside is that
NOMMU mode requires some extra memory to track things over NOMMU without this
patch (VMAs are no longer shared, and there are now region structs).
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Mike Frysinger <vapier.adi@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
overlay thread.usp over PT_USP when getting the whole regfile to
match PT_USP behavior
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Blackfin dual core BF561 processor can support SMP like features.
https://docs.blackfin.uclinux.org/doku.php?id=linux-kernel:smp-like
In this patch, we provide SMP extend to Blackfin kernel and memory management code
Singed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Fix some really ancient code that was correct only for the m68k port.
Delete unused (i.e. copied from m68k) entries in asm-offsets.c.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Identical handlers of PTRACE_DETACH go into ptrace_request().
Not touching compat code.
Not touching archs that don't call ptrace_request.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This finally renames the thread_info field in task structure to stack, so that
the assumptions about this field are gone and archs have more freedom about
placing the thread_info structure.
Nonbroken archs which have a proper thread pointer can do the access to both
current thread and task structure via a single pointer.
It'll allow for a few more cleanups of the fork code, from which e.g. ia64
could benefit.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
[akpm@linux-foundation.org: build fix]
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Richard Curnow <rc@rc0.org.uk>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Cc: Andi Kleen <ak@muc.de>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds support for the Analog Devices Blackfin processor architecture, and
currently supports the BF533, BF532, BF531, BF537, BF536, BF534, and BF561
(Dual Core) devices, with a variety of development platforms including those
avaliable from Analog Devices (BF533-EZKit, BF533-STAMP, BF537-STAMP,
BF561-EZKIT), and Bluetechnix! Tinyboards.
The Blackfin architecture was jointly developed by Intel and Analog Devices
Inc. (ADI) as the Micro Signal Architecture (MSA) core and introduced it in
December of 2000. Since then ADI has put this core into its Blackfin
processor family of devices. The Blackfin core has the advantages of a clean,
orthogonal,RISC-like microprocessor instruction set. It combines a dual-MAC
(Multiply/Accumulate), state-of-the-art signal processing engine and
single-instruction, multiple-data (SIMD) multimedia capabilities into a single
instruction-set architecture.
The Blackfin architecture, including the instruction set, is described by the
ADSP-BF53x/BF56x Blackfin Processor Programming Reference
http://blackfin.uclinux.org/gf/download/frsrelease/29/2549/Blackfin_PRM.pdf
The Blackfin processor is already supported by major releases of gcc, and
there are binary and source rpms/tarballs for many architectures at:
http://blackfin.uclinux.org/gf/project/toolchain/frs There is complete
documentation, including "getting started" guides available at:
http://docs.blackfin.uclinux.org/ which provides links to the sources and
patches you will need in order to set up a cross-compiling environment for
bfin-linux-uclibc
This patch, as well as the other patches (toolchain, distribution,
uClibc) are actively supported by Analog Devices Inc, at:
http://blackfin.uclinux.org/
We have tested this on LTP, and our test plan (including pass/fails) can
be found at:
http://docs.blackfin.uclinux.org/doku.php?id=testing_the_linux_kernel
[m.kozlowski@tuxland.pl: balance parenthesis in blackfin header files]
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
Signed-off-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl>
Signed-off-by: Aubrey Li <aubrey.li@analog.com>
Signed-off-by: Jie Zhang <jie.zhang@analog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
