Commit Graph

23 Commits

Author SHA1 Message Date
Andy Lutomirski f56141e3e2 all arches, signal: move restart_block to struct task_struct
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: Andy 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: Richard 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: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:12 -08:00
Richard Weinberger 2bb12b773f score: Use get_signal() signal_setup_done()
Use the more generic functions get_signal() signal_setup_done()
for signal delivery.

Acked-by: Lennox Wu <lennox.wu@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2014-08-06 13:03:10 +02:00
Al Viro b774cc5cb6 score: switch to generic sigaltstack
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-03 18:16:15 -05:00
Al Viro afd3f96dc3 score: do_sigaltstack() expects a userland pointer...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-28 21:46:12 -05:00
Al Viro af445f45ed score: fix bogus restarts on sigreturn()
we *really* don't want to have restart logics hit when we are returning from
sigreturn() - random replacement of %r4 with -4 just because a signal had
been noticed from timer interrupt that came when %r4 happened to contain
-514 is not nice at all.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-01 09:58:10 -04:00
Al Viro efee984c27 new helper: signal_delivered()
Does block_sigmask() + tracehook_signal_handler();  called when
sigframe has been successfully built.  All architectures converted
to it; block_sigmask() itself is gone now (merged into this one).

I'm still not too happy with the signature, but that's a separate
story (IMO we need a structure that would contain signal number +
siginfo + k_sigaction, so that get_signal_to_deliver() would fill one,
signal_delivered(), handle_signal() and probably setup...frame() -
take one).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:52 -04:00
Al Viro 77097ae503 most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from set
Only 3 out of 63 do not.  Renamed the current variant to __set_current_blocked(),
added set_current_blocked() that will exclude unblockable signals, switched
open-coded instances to it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:51 -04:00
Al Viro a610d6e672 pull clearing RESTORE_SIGMASK into block_sigmask()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:49 -04:00
Al Viro b7f9a11a6c new helper: sigmask_to_save()
replace boilerplate "should we use ->saved_sigmask or ->blocked?"
with calls of obvious inlined helper...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:48 -04:00
Al Viro 51a7b448d4 new helper: restore_saved_sigmask()
first fruits of ..._restore_sigmask() helpers: now we can take
boilerplate "signal didn't have a handler, clear RESTORE_SIGMASK
and restore the blocked mask from ->saved_mask" into a common
helper.  Open-coded instances switched...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:58:47 -04:00
Al Viro a42c6ded82 move key_repace_session_keyring() into tracehook_notify_resume()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-23 22:09:20 -04:00
Al Viro 1d5d4dbe81 score: add handling of NOTIFY_RESUME to do_notify_resume()
It's already called if TIF_NOTIFY_RESUME is set, so we only
need to add the actual work.  Note that checking for RESTORE_SIGMASK
was not needed - set_restore_sigmask() also sets SIGPENDING, so
we never RESTORE_SIGMASK without SIGPENDING.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21 23:59:47 -04:00
Al Viro cf4a0ce45c score: don't open-code force_sigsegv()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21 23:59:19 -04:00
Al Viro f2ccfb3e56 score: ->restart_block.fn needs to be reset on rt_sigreturn
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21 23:52:39 -04:00
Matt Fleming 4c3181bd3b score: use set_current_blocked() and block_sigmask()
As described in e6fa16ab ("signal: sigprocmask() should do
retarget_shared_pending()") the modification of current->blocked is
incorrect as we need to check whether the signal we're about to block is
pending in the shared queue.

Also, use the new helper function introduced in commit 5e6292c0f2
("signal: add block_sigmask() for adding sigmask to current->blocked")
which centralises the code for updating current->blocked after
successfully delivering a signal and reduces the amount of duplicate code
across architectures.  In the past some architectures got this code wrong,
so using this helper function should stop that from happening again.

Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21 23:52:33 -04:00
Matt Fleming 80c1dfa91c score: don't mask signals if we fail to setup signal stack
If setup_rt_frame() returns -EFAULT then we must not block any signals
in the current process.

Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21 23:52:32 -04:00
Chen Liqin d8aa899bb2 score: remove unused code, add include files in .c 2009-08-30 12:26:32 +08:00
Arnd Bergmann c606747225 score: cleanups: dead code, 0 as pointer, shadowed variables
A few smaller issues found by sparse, some code that was
never used, two instances of '0' instead of 'NULL' and
local variables shadowing another one.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2009-06-27 15:16:16 +02:00
Arnd Bergmann bddc605955 score: fix function prototypes
Syscalls should return 'long' and be marked as 'asmlinkage'.
Functions that are only used in a single file should be 'static'.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2009-06-27 15:14:58 +02:00
Arnd Bergmann a1f8213b95 score: add address space annotations
Annotate the address space for pointers that are used
correctly with __user and __iomem, so that sparse
can better warn about incorrect casts.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2009-06-27 15:09:52 +02:00
Arnd Bergmann 9fb24cc500 score: add missing #includes
Files that define a global function should #include the
header with its declaration to make sure that the prototypes
do not diverge.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2009-06-27 15:09:46 +02:00
Chen Liqin 0402c91af9 score: update files according to review comments
modified:   arch/score/include/asm/cacheflush.h
	modified:   arch/score/include/asm/delay.h
	modified:   arch/score/include/asm/errno.h
	modified:   arch/score/include/asm/pgtable-bits.h
	modified:   arch/score/include/asm/pgtable.h
	modified:   arch/score/include/asm/ptrace.h
	modified:   arch/score/include/asm/unistd.h
	modified:   arch/score/kernel/entry.S
	modified:   arch/score/kernel/process.c
	modified:   arch/score/kernel/ptrace.c
	modified:   arch/score/kernel/signal.c
	modified:   arch/score/kernel/sys_score.c
	modified:   arch/score/kernel/traps.c
	modified:   arch/score/mm/cache.c

Signed-off-by: Chen Liqin <liqin.chen@sunplusct.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2009-06-19 11:40:13 +02:00
Chen Liqin 6bc9a3966f score: Add support for Sunplus S+core architecture
This is the complete set of new arch Score's files for linux.
Score instruction set support 16bits, 32bits and 64bits instruction,
Score SOC had been used in game machine and LCD TV.

Signed-off-by: Chen Liqin <liqin.chen@sunplusct.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2009-06-19 11:38:47 +02:00