1. 24 7月, 2017 2 次提交
    • D
      ARM: 8687/1: signal: Fix unparseable iwmmxt_sigframe in uc_regspace[] · ce184a0d
      Dave Martin 提交于
      In kernels with CONFIG_IWMMXT=y running on non-iWMMXt hardware, the
      signal frame can be left partially uninitialised in such a way
      that userspace cannot parse uc_regspace[] safely.  In particular,
      this means that the VFP registers cannot be located reliably in the
      signal frame when a multi_v7_defconfig kernel is run on the
      majority of platforms.
      
      The cause is that the uc_regspace[] is laid out statically based on
      the kernel config, but the decision of whether to save/restore the
      iWMMXt registers must be a runtime decision.
      
      To minimise breakage of software that may assume a fixed layout,
      this patch emits a dummy block of the same size as iwmmxt_sigframe,
      for non-iWMMXt threads.  However, the magic and size of this block
      are now filled in to help parsers skip over it.  A new DUMMY_MAGIC
      is defined for this purpose.
      
      It is probably legitimate (if non-portable) for userspace to
      manufacture its own sigframe for sigreturn, and there is no obvious
      reason why userspace should be required to insert a DUMMY_MAGIC
      block when running on non-iWMMXt hardware, when omitting it has
      worked just fine forever in other configurations.  So in this case,
      sigreturn does not require this block to be present.
      Reported-by: NEdmund Grimley-Evans <Edmund.Grimley-Evans@arm.com>
      Signed-off-by: NDave Martin <Dave.Martin@arm.com>
      Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
      ce184a0d
    • D
      ARM: 8686/1: iwmmxt: Add missing __user annotations to sigframe accessors · 26958355
      Dave Martin 提交于
      preserve_iwmmxt_context() and restore_iwmmxt_context() lack __user
      accessors on their arguments pointing to the user signal frame.
      
      There does not be appear to be a bug here, but this omission is
      inconsistent with the crunch and vfp sigframe access functions.
      
      This patch adds the annotations, for consistency.
      Signed-off-by: NDave Martin <Dave.Martin@arm.com>
      Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
      26958355
  2. 17 9月, 2015 1 次提交
  3. 16 9月, 2015 1 次提交
  4. 25 8月, 2015 1 次提交
  5. 13 4月, 2015 1 次提交
  6. 13 2月, 2015 1 次提交
    • A
      all arches, signal: move restart_block to struct task_struct · f56141e3
      Andy Lutomirski 提交于
      If an attacker can cause a controlled kernel stack overflow, overwriting
      the restart block is a very juicy exploit target.  This is because the
      restart_block is held in the same memory allocation as the kernel stack.
      
      Moving the restart block to struct task_struct prevents this exploit by
      making the restart_block harder to locate.
      
      Note that there are other fields in thread_info that are also easy
      targets, at least on some architectures.
      
      It's also a decent simplification, since the restart code is more or less
      identical on all architectures.
      
      [james.hogan@imgtec.com: metag: align thread_info::supervisor_stack]
      Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: David Miller <davem@davemloft.net>
      Acked-by: NRichard Weinberger <richard@nod.at>
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Cc: Matt Turner <mattst88@gmail.com>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Russell King <rmk@arm.linux.org.uk>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
      Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
      Cc: Steven Miao <realmz6@gmail.com>
      Cc: Mark Salter <msalter@redhat.com>
      Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
      Cc: Mikael Starvik <starvik@axis.com>
      Cc: Jesper Nilsson <jesper.nilsson@axis.com>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Richard Kuo <rkuo@codeaurora.org>
      Cc: "Luck, Tony" <tony.luck@intel.com>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Michal Simek <monstr@monstr.eu>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Jonas Bonn <jonas@southpole.se>
      Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
      Cc: Helge Deller <deller@gmx.de>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
      Tested-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Chen Liqin <liqin.linux@gmail.com>
      Cc: Lennox Wu <lennox.wu@gmail.com>
      Cc: Chris Metcalf <cmetcalf@ezchip.com>
      Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
      Cc: Chris Zankel <chris@zankel.net>
      Cc: Max Filippov <jcmvbkbc@gmail.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Guenter Roeck <linux@roeck-us.net>
      Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      f56141e3
  7. 18 11月, 2014 1 次提交
  8. 19 3月, 2014 1 次提交
  9. 07 11月, 2013 1 次提交
  10. 20 10月, 2013 1 次提交
  11. 03 8月, 2013 2 次提交
  12. 01 8月, 2013 1 次提交
    • R
      ARM: move signal handlers into a vdso-like page · 48be69a0
      Russell King 提交于
      Move the signal handlers into a VDSO page rather than keeping them in
      the vectors page.  This allows us to place them randomly within this
      page, and also map the page at a random location within userspace
      further protecting these code fragments from ROP attacks.  The new
      VDSO page is also poisoned in the same way as the vector page.
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      48be69a0
  13. 17 6月, 2013 1 次提交
    • J
      ARM: mpu: protect the vectors page with an MPU region · 9dfc28b6
      Jonathan Austin 提交于
      Without an MMU it is possible for userspace programs to start executing code
      in places that they have no business executing. The MPU allows some level of
      protection against this.
      
      This patch protects the vectors page from access by userspace processes.
      Userspace tasks that dereference a null pointer are already protected by an
      svc at 0x0 that kills them. However when tasks use an offset from a null
      pointer (eg a function in a null struct) they miss this carefully placed svc
      and enter the exception vectors in user mode, ending up in the kernel.
      
      This patch causes programs that do this to receive a SEGV instead of happily
      entering the kernel in user-mode, and hence avoid a 'Bad Mode' panic.
      
      As part of this change it is necessary to make sigreturn happen via the
      stack when there is not an sa_restorer function. This change is invisible to
      userspace, and irrelevant to code compiled using a uClibc toolchain, which
      always uses an sa_restorer function.
      
      Because we don't get to remap the vectors in !MMU kuser_helpers are not
      in a defined location, and hence aren't usable. This means we don't need to
      worry about keeping them accessible from PL0
      Signed-off-by: NJonathan Austin <jonathan.austin@arm.com>
      Reviewed-by: NWill Deacon <will.deacon@arm.com>
      CC: Nicolas Pitre <nico@linaro.org>
      CC: Catalin Marinas <catalin.marinas@arm.com>
      9dfc28b6
  14. 14 2月, 2013 1 次提交
  15. 04 2月, 2013 3 次提交
  16. 01 10月, 2012 1 次提交
  17. 28 7月, 2012 5 次提交
  18. 05 7月, 2012 2 次提交
  19. 02 6月, 2012 5 次提交
  20. 24 5月, 2012 1 次提交
  21. 22 5月, 2012 7 次提交