1. 17 2月, 2015 1 次提交
  2. 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
  3. 06 8月, 2014 1 次提交
  4. 27 8月, 2013 1 次提交
  5. 01 8月, 2013 1 次提交
  6. 03 3月, 2013 1 次提交
  7. 21 2月, 2013 1 次提交
  8. 04 2月, 2013 1 次提交
  9. 08 1月, 2013 1 次提交
  10. 01 10月, 2012 2 次提交
  11. 02 6月, 2012 6 次提交
  12. 24 5月, 2012 1 次提交
  13. 22 5月, 2012 2 次提交
  14. 31 3月, 2011 1 次提交
  15. 30 11月, 2010 1 次提交
  16. 13 2月, 2010 1 次提交
  17. 16 12月, 2009 1 次提交
  18. 28 9月, 2009 2 次提交
  19. 09 9月, 2009 1 次提交
  20. 02 9月, 2009 2 次提交
    • D
      KEYS: Add a keyctl to install a process's session keyring on its parent [try #6] · ee18d64c
      David Howells 提交于
      Add a keyctl to install a process's session keyring onto its parent.  This
      replaces the parent's session keyring.  Because the COW credential code does
      not permit one process to change another process's credentials directly, the
      change is deferred until userspace next starts executing again.  Normally this
      will be after a wait*() syscall.
      
      To support this, three new security hooks have been provided:
      cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in
      the blank security creds and key_session_to_parent() - which asks the LSM if
      the process may replace its parent's session keyring.
      
      The replacement may only happen if the process has the same ownership details
      as its parent, and the process has LINK permission on the session keyring, and
      the session keyring is owned by the process, and the LSM permits it.
      
      Note that this requires alteration to each architecture's notify_resume path.
      This has been done for all arches barring blackfin, m68k* and xtensa, all of
      which need assembly alteration to support TIF_NOTIFY_RESUME.  This allows the
      replacement to be performed at the point the parent process resumes userspace
      execution.
      
      This allows the userspace AFS pioctl emulation to fully emulate newpag() and
      the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to
      alter the parent process's PAG membership.  However, since kAFS doesn't use
      PAGs per se, but rather dumps the keys into the session keyring, the session
      keyring of the parent must be replaced if, for example, VIOCSETTOK is passed
      the newpag flag.
      
      This can be tested with the following program:
      
      	#include <stdio.h>
      	#include <stdlib.h>
      	#include <keyutils.h>
      
      	#define KEYCTL_SESSION_TO_PARENT	18
      
      	#define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0)
      
      	int main(int argc, char **argv)
      	{
      		key_serial_t keyring, key;
      		long ret;
      
      		keyring = keyctl_join_session_keyring(argv[1]);
      		OSERROR(keyring, "keyctl_join_session_keyring");
      
      		key = add_key("user", "a", "b", 1, keyring);
      		OSERROR(key, "add_key");
      
      		ret = keyctl(KEYCTL_SESSION_TO_PARENT);
      		OSERROR(ret, "KEYCTL_SESSION_TO_PARENT");
      
      		return 0;
      	}
      
      Compiled and linked with -lkeyutils, you should see something like:
      
      	[dhowells@andromeda ~]$ keyctl show
      	Session Keyring
      	       -3 --alswrv   4043  4043  keyring: _ses
      	355907932 --alswrv   4043    -1   \_ keyring: _uid.4043
      	[dhowells@andromeda ~]$ /tmp/newpag
      	[dhowells@andromeda ~]$ keyctl show
      	Session Keyring
      	       -3 --alswrv   4043  4043  keyring: _ses
      	1055658746 --alswrv   4043  4043   \_ user: a
      	[dhowells@andromeda ~]$ /tmp/newpag hello
      	[dhowells@andromeda ~]$ keyctl show
      	Session Keyring
      	       -3 --alswrv   4043  4043  keyring: hello
      	340417692 --alswrv   4043  4043   \_ user: a
      
      Where the test program creates a new session keyring, sticks a user key named
      'a' into it and then installs it on its parent.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NJames Morris <jmorris@namei.org>
      ee18d64c
    • D
      KEYS: Extend TIF_NOTIFY_RESUME to (almost) all architectures [try #6] · d0420c83
      David Howells 提交于
      Implement TIF_NOTIFY_RESUME for most of those architectures in which isn't yet
      available, and, whilst we're at it, have it call the appropriate tracehook.
      
      After this patch, blackfin, m68k* and xtensa still lack support and need
      alteration of assembly code to make it work.
      
      Resume notification can then be used (by a later patch) to install a new
      session keyring on the parent of a process.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      
      cc: linux-arch@vger.kernel.org
      Signed-off-by: NJames Morris <jmorris@namei.org>
      d0420c83
  21. 14 11月, 2008 1 次提交
  22. 16 4月, 2008 1 次提交
  23. 03 2月, 2008 1 次提交
  24. 20 10月, 2007 1 次提交
    • P
      pid namespaces: changes to show virtual ids to user · b488893a
      Pavel Emelyanov 提交于
      This is the largest patch in the set. Make all (I hope) the places where
      the pid is shown to or get from user operate on the virtual pids.
      
      The idea is:
       - all in-kernel data structures must store either struct pid itself
         or the pid's global nr, obtained with pid_nr() call;
       - when seeking the task from kernel code with the stored id one
         should use find_task_by_pid() call that works with global pids;
       - when showing pid's numerical value to the user the virtual one
         should be used, but however when one shows task's pid outside this
         task's namespace the global one is to be used;
       - when getting the pid from userspace one need to consider this as
         the virtual one and use appropriate task/pid-searching functions.
      
      [akpm@linux-foundation.org: build fix]
      [akpm@linux-foundation.org: nuther build fix]
      [akpm@linux-foundation.org: yet nuther build fix]
      [akpm@linux-foundation.org: remove unneeded casts]
      Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
      Signed-off-by: NAlexey Dobriyan <adobriyan@openvz.org>
      Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
      Cc: Oleg Nesterov <oleg@tv-sign.ru>
      Cc: Paul Menage <menage@google.com>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b488893a
  25. 09 5月, 2007 1 次提交
  26. 17 2月, 2007 3 次提交
  27. 04 10月, 2006 1 次提交
  28. 28 6月, 2006 1 次提交
  29. 23 6月, 2006 1 次提交
    • L
      [PATCH] fix incorrect SA_ONSTACK behaviour for 64-bit processes · d09042da
      Laurent MEYER 提交于
      - When setting a sighandler using sigaction() call, if the flag
        SA_ONSTACK is set and no alternate stack is provided via sigaltstack(),
        the kernel still try to install the alternate stack.  This behavior is
        the opposite of the one which is documented in Single Unix Specifications
        V3.
      
      - Also when setting an alternate stack using sigaltstack() with the flag
        SS_DISABLE, the kernel try to install the alternate stack on signal
        delivery.
      
      These two use cases makes the process crash at signal delivery.
      Signed-off-by: NLaurent Meyer <meyerlau@fr.ibm.com>
      Cc: Richard Henderson <rth@twiddle.net>
      Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Cc: Geert Uytterhoeven <geert@linux-m68k.org>
      Cc: Roman Zippel <zippel@linux-m68k.org>
      Cc: Kyle McMartin <kyle@mcmartin.ca>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
      Cc: Chris Zankel <chris@zankel.net>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      d09042da