Commit Graph

121 Commits

Author SHA1 Message Date
Stephen Rothwell 89963adcdb kernel/compat.c: mark expected switch fall-throughs
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

This patch aims to suppress 3 missing-break-in-switch false positives
on some architectures.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Gustavo A. R. Silva <gustavo@embeddedor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-15 08:16:14 -07:00
Arnd Bergmann 4d5f007eed time: make adjtime compat handling available for 32 bit
We want to reuse the compat_timex handling on 32-bit architectures the
same way we are using the compat handling for timespec when moving to
64-bit time_t.

Move all definitions related to compat_timex out of the compat code
into the normal timekeeping code, along with a rename to old_timex32,
corresponding to the timespec/timeval structures, and make it controlled
by CONFIG_COMPAT_32BIT_TIME, which 32-bit architectures will then select.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2019-02-07 00:13:27 +01:00
Linus Torvalds 594cc251fd make 'user_access_begin()' do 'access_ok()'
Originally, the rule used to be that you'd have to do access_ok()
separately, and then user_access_begin() before actually doing the
direct (optimized) user access.

But experience has shown that people then decide not to do access_ok()
at all, and instead rely on it being implied by other operations or
similar.  Which makes it very hard to verify that the access has
actually been range-checked.

If you use the unsafe direct user accesses, hardware features (either
SMAP - Supervisor Mode Access Protection - on x86, or PAN - Privileged
Access Never - on ARM) do force you to use user_access_begin().  But
nothing really forces the range check.

By putting the range check into user_access_begin(), we actually force
people to do the right thing (tm), and the range check vill be visible
near the actual accesses.  We have way too long a history of people
trying to avoid them.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-04 12:56:09 -08:00
Linus Torvalds 96d4f267e4 Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-03 18:57:57 -08:00
Arnd Bergmann 9afc5eee65 y2038: globally rename compat_time to old_time32
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 <hch@infradead.org>
Link: https://lore.kernel.org/lkml/20180705222110.GA5698@infradead.org/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-08-27 14:48:48 +02:00
Deepa Dinamani afef05cf23 time: Enable get/put_compat_itimerspec64 always
This will aid in enabling the compat syscalls on 32-bit architectures later
on.

Also move compat_itimerspec and related defines to compat_time.h.  The
compat_time.h file will eventually be deleted.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: arnd@arndb.de
Cc: viro@zeniv.linux.org.uk
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-api@vger.kernel.org
Cc: y2038@lists.linaro.org
Link: https://lkml.kernel.org/r/20180617051144.29756-3-deepa.kernel@gmail.com
2018-06-24 14:39:47 +02:00
Linus Torvalds 0bbcce5d1e Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timers and timekeeping updates from Thomas Gleixner:

 - Core infrastucture work for Y2038 to address the COMPAT interfaces:

     + Add a new Y2038 safe __kernel_timespec and use it in the core
       code

     + Introduce config switches which allow to control the various
       compat mechanisms

     + Use the new config switch in the posix timer code to control the
       32bit compat syscall implementation.

 - Prevent bogus selection of CPU local clocksources which causes an
   endless reselection loop

 - Remove the extra kthread in the clocksource code which has no value
   and just adds another level of indirection

 - The usual bunch of trivial updates, cleanups and fixlets all over the
   place

 - More SPDX conversions

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  clocksource/drivers/mxs_timer: Switch to SPDX identifier
  clocksource/drivers/timer-imx-tpm: Switch to SPDX identifier
  clocksource/drivers/timer-imx-gpt: Switch to SPDX identifier
  clocksource/drivers/timer-imx-gpt: Remove outdated file path
  clocksource/drivers/arc_timer: Add comments about locking while read GFRC
  clocksource/drivers/mips-gic-timer: Add pr_fmt and reword pr_* messages
  clocksource/drivers/sprd: Fix Kconfig dependency
  clocksource: Move inline keyword to the beginning of function declarations
  timer_list: Remove unused function pointer typedef
  timers: Adjust a kernel-doc comment
  tick: Prefer a lower rating device only if it's CPU local device
  clocksource: Remove kthread
  time: Change nanosleep to safe __kernel_* types
  time: Change types to new y2038 safe __kernel_* types
  time: Fix get_timespec64() for y2038 safe compat interfaces
  time: Add new y2038 safe __kernel_timespec
  posix-timers: Make compat syscalls depend on CONFIG_COMPAT_32BIT_TIME
  time: Introduce CONFIG_COMPAT_32BIT_TIME
  time: Introduce CONFIG_64BIT_TIME in architectures
  compat: Enable compat_get/put_timespec64 always
  ...
2018-06-04 20:27:54 -07:00
Jann Horn 0a0b987344 compat: fix 4-byte infoleak via uninitialized struct field
Commit 3a4d44b616 ("ntp: Move adjtimex related compat syscalls to
native counterparts") removed the memset() in compat_get_timex().  Since
then, the compat adjtimex syscall can invoke do_adjtimex() with an
uninitialized ->tai.

If do_adjtimex() doesn't write to ->tai (e.g.  because the arguments are
invalid), compat_put_timex() then copies the uninitialized ->tai field
to userspace.

Fix it by adding the memset() back.

Fixes: 3a4d44b616 ("ntp: Move adjtimex related compat syscalls to native counterparts")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-10 17:51:58 -07:00
Deepa Dinamani 1c68adf61e compat: Enable compat_get/put_timespec64 always
These functions are used in the repurposed compat syscalls
to provide backward compatibility for using 32 bit time_t
on 32 bit systems.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-04-19 13:30:14 +02:00
Dominik Brodowski 7addf44388 mm: add kernel_move_pages() helper, move compat syscall to mm/migrate.c
Move compat_sys_move_pages() to mm/migrate.c and make it call a newly
introduced helper -- kernel_move_pages() -- instead of the syscall.

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-mm@kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02 20:15:32 +02:00
Dominik Brodowski b6e9b0babb mm: add kernel_migrate_pages() helper, move compat syscall to mm/mempolicy.c
Move compat_sys_migrate_pages() to mm/mempolicy.c and make it call a newly
introduced helper -- kernel_migrate_pages() -- instead of the syscall.

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-mm@kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02 20:15:31 +02:00
Matt Redfearn fde9fc766e
signals: Move put_compat_sigset to compat.h to silence hardened usercopy
Since commit afcc90f862 ("usercopy: WARN() on slab cache usercopy
region violations"), MIPS systems booting with a compat root filesystem
emit a warning when copying compat siginfo to userspace:

WARNING: CPU: 0 PID: 953 at mm/usercopy.c:81 usercopy_warn+0x98/0xe8
Bad or missing usercopy whitelist? Kernel memory exposure attempt
detected from SLAB object 'task_struct' (offset 1432, size 16)!
Modules linked in:
CPU: 0 PID: 953 Comm: S01logging Not tainted 4.16.0-rc2 #10
Stack : ffffffff808c0000 0000000000000000 0000000000000001 65ac85163f3bdc4a
	65ac85163f3bdc4a 0000000000000000 90000000ff667ab8 ffffffff808c0000
	00000000000003f8 ffffffff808d0000 00000000000000d1 0000000000000000
	000000000000003c 0000000000000000 ffffffff808c8ca8 ffffffff808d0000
	ffffffff808d0000 ffffffff80810000 fffffc0000000000 ffffffff80785c30
	0000000000000009 0000000000000051 90000000ff667eb0 90000000ff667db0
	000000007fe0d938 0000000000000018 ffffffff80449958 0000000020052798
	ffffffff808c0000 90000000ff664000 90000000ff667ab0 00000000100c0000
	ffffffff80698810 0000000000000000 0000000000000000 0000000000000000
	0000000000000000 0000000000000000 ffffffff8010d02c 65ac85163f3bdc4a
	...
Call Trace:
[<ffffffff8010d02c>] show_stack+0x9c/0x130
[<ffffffff80698810>] dump_stack+0x90/0xd0
[<ffffffff80137b78>] __warn+0x100/0x118
[<ffffffff80137bdc>] warn_slowpath_fmt+0x4c/0x70
[<ffffffff8021e4a8>] usercopy_warn+0x98/0xe8
[<ffffffff8021e68c>] __check_object_size+0xfc/0x250
[<ffffffff801bbfb8>] put_compat_sigset+0x30/0x88
[<ffffffff8011af24>] setup_rt_frame_n32+0xc4/0x160
[<ffffffff8010b8b4>] do_signal+0x19c/0x230
[<ffffffff8010c408>] do_notify_resume+0x60/0x78
[<ffffffff80106f50>] work_notifysig+0x10/0x18
---[ end trace 88fffbf69147f48a ]---

Commit 5905429ad8 ("fork: Provide usercopy whitelisting for
task_struct") noted that:

"While the blocked and saved_sigmask fields of task_struct are copied to
userspace (via sigmask_to_save() and setup_rt_frame()), it is always
copied with a static length (i.e. sizeof(sigset_t))."

However, this is not true in the case of compat signals, whose sigset
is copied by put_compat_sigset and receives size as an argument.

At most call sites, put_compat_sigset is copying a sigset from the
current task_struct. This triggers a warning when
CONFIG_HARDENED_USERCOPY is active. However, by marking this function as
static inline, the warning can be avoided because in all of these cases
the size is constant at compile time, which is allowed. The only site
where this is not the case is handling the rt_sigpending syscall, but
there the copy is being made from a stack local variable so does not
trigger the warning.

Move put_compat_sigset to compat.h, and mark it static inline. This
fixes the WARN on MIPS.

Fixes: afcc90f862 ("usercopy: WARN() on slab cache usercopy region violations")
Signed-off-by: Matt Redfearn <matt.redfearn@mips.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: "Dmitry V . Levin" <ldv@altlinux.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: kernel-hardening@lists.openwall.com
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/18639/
Signed-off-by: James Hogan <jhogan@kernel.org>
2018-03-02 21:31:55 +00:00
Alexey Dobriyan 4de373a12f cpumask: make cpumask_size() return "unsigned int"
CPUmasks are never big enough to warrant 64-bit code.

Space savings:

	add/remove: 0/0 grow/shrink: 1/4 up/down: 3/-17 (-14)
	Function                                     old     new   delta
	sched_init_numa                             1530    1533      +3
	compat_sys_sched_setaffinity                 160     159      -1
	sys_sched_getaffinity                        197     195      -2
	sys_sched_setaffinity                        183     176      -7
	compat_sys_sched_getaffinity                 179     172      -7

Link: http://lkml.kernel.org/r/20171204165531.GA8221@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-06 18:32:45 -08:00
Al Viro abca5fc535 sched_rr_get_interval(): move compat to native, get rid of set_fs()
switch to using timespec64 internally, while we are at it

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-20 00:30:57 -04:00
Al Viro 3968cf6238 get_compat_sigset()
similar to put_compat_sigset()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-19 17:56:01 -04:00
Al Viro b8e8e1aa9f get rid of {get,put}_compat_itimerspec()
no users left

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-19 17:56:00 -04:00
Dmitry V. Levin f454322efb signal: replace sigset_to_compat() with put_compat_sigset()
There are 4 callers of sigset_to_compat() in the entire kernel.  One is
in sparc compat rt_sigaction(2), the rest are in kernel/signal.c itself.
All are followed by copy_to_user(), and all but the sparc one are under
"if it's big-endian..." ifdefs.

Let's transform sigset_to_compat() into put_compat_sigset() that also
calls copy_to_user().

Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-19 17:55:54 -04:00
Al Viro 44ee454670 semtimedop(): move compat to native
... and finally kill the sodding compat_convert_timespec()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-07-15 20:46:47 -04:00
Linus Torvalds c856863988 Merge branch 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc compat stuff updates from Al Viro:
 "This part is basically untangling various compat stuff. Compat
  syscalls moved to their native counterparts, getting rid of quite a
  bit of double-copying and/or set_fs() uses. A lot of field-by-field
  copyin/copyout killed off.

   - kernel/compat.c is much closer to containing just the
     copyin/copyout of compat structs. Not all compat syscalls are gone
     from it yet, but it's getting there.

   - ipc/compat_mq.c killed off completely.

   - block/compat_ioctl.c cleaned up; floppy compat ioctls moved to
     drivers/block/floppy.c where they belong. Yes, there are several
     drivers that implement some of the same ioctls. Some are m68k and
     one is 32bit-only pmac. drivers/block/floppy.c is the only one in
     that bunch that can be built on biarch"

* 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  mqueue: move compat syscalls to native ones
  usbdevfs: get rid of field-by-field copyin
  compat_hdio_ioctl: get rid of set_fs()
  take floppy compat ioctls to sodding floppy.c
  ipmi: get rid of field-by-field __get_user()
  ipmi: get COMPAT_IPMICTL_RECEIVE_MSG in sync with the native one
  rt_sigtimedwait(): move compat to native
  select: switch compat_{get,put}_fd_set() to compat_{get,put}_bitmap()
  put_compat_rusage(): switch to copy_to_user()
  sigpending(): move compat to native
  getrlimit()/setrlimit(): move compat to native
  times(2): move compat to native
  compat_{get,put}_bitmap(): use unsafe_{get,put}_user()
  fb_get_fscreeninfo(): don't bother with do_fb_ioctl()
  do_sigaltstack(): lift copying to/from userland into callers
  take compat_sys_old_getrlimit() to native syscall
  trim __ARCH_WANT_SYS_OLD_GETRLIMIT
2017-07-06 20:57:13 -07:00
Linus Torvalds ea3b25e132 Merge branch 'timers-compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull timer-related user access updates from Al Viro:
 "Continuation of timers-related stuff (there had been more, but my
  parts of that series are already merged via timers/core). This is more
  of y2038 work by Deepa Dinamani, partially disrupted by the
  unification of native and compat timers-related syscalls"

* 'timers-compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  posix_clocks: Use get_itimerspec64() and put_itimerspec64()
  timerfd: Use get_itimerspec64() and put_itimerspec64()
  nanosleep: Use get_timespec64() and put_timespec64()
  posix-timers: Use get_timespec64() and put_timespec64()
  posix-stubs: Conditionally include COMPAT_SYS_NI defines
  time: introduce {get,put}_itimerspec64
  time: add get_timespec64 and put_timespec64
2017-07-05 15:34:35 -07:00
Linus Torvalds 4be95131bf Merge branch 'work.sys_wait' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull wait syscall updates from Al Viro:
 "Consolidating sys_wait* and compat counterparts.

  Gets rid of set_fs()/double-copy mess, simplifies the whole thing
  (lifting the copyouts to the syscalls means less headache in the part
  that does actual work - fewer failure exits, to start with), gets rid
  of the overhead of field-by-field __put_user()"

* 'work.sys_wait' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  osf_wait4: switch to kernel_wait4()
  waitid(): switch copyout of siginfo to unsafe_put_user()
  wait_task_zombie: consolidate info logics
  kill wait_noreap_copyout()
  lift getrusage() from wait_noreap_copyout()
  waitid(2): leave copyout of siginfo to syscall itself
  kernel_wait4()/kernel_waitid(): delay copying status to userland
  wait4(2)/waitid(2): separate copying rusage to userland
  move compat wait4 and waitid next to native variants
2017-07-05 14:10:19 -07:00
Deepa Dinamani d5b7ffbfbd time: introduce {get,put}_itimerspec64
As we change the user space type for the timerfd and posix timer
functions to newer data types, we need some form of conversion
helpers to avoid duplicating that logic.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-25 21:58:46 -04:00
Deepa Dinamani f59dd9c886 time: add get_timespec64 and put_timespec64
Add helper functions to convert between struct timespec64 and
struct timespec at userspace boundaries.

This is a preparatory patch to use timespec64 as the basic type
internally in the kernel as timespec is not y2038 safe on 32 bit systems.
The patch helps the cause by containing all data conversions at the
userspace boundaries within these functions.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-25 21:58:46 -04:00
Al Viro 2b2d02856b time: Move compat_gettimeofday()/settimeofday() to native
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-16-viro@ZenIV.linux.org.uk
2017-06-14 00:00:46 +02:00
Al Viro b180db2c8c time: Move compat_time()/stime() to native
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-15-viro@ZenIV.linux.org.uk
2017-06-14 00:00:45 +02:00
Al Viro 2482097c6c posix-timers: Move compat_timer_create() to native, get rid of set_fs()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-14-viro@ZenIV.linux.org.uk
2017-06-14 00:00:45 +02:00
Al Viro d822cdcce4 posix-timers: Move compat versions of clock_gettime/settime/getres
Move them to the native implementations and get rid of the set_fs() hackery.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-13-viro@ZenIV.linux.org.uk
2017-06-14 00:00:44 +02:00
Al Viro 54ad9c46c2 itimers: Move compat itimer syscalls to native ones
get rid of set_fs(), sanitize compat copyin/copyout.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-12-viro@ZenIV.linux.org.uk
2017-06-14 00:00:44 +02:00
Al Viro b0dc12426e posix-timers: Take compat timer_gettime(2) to native one
... and get rid of set_fs() in there

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-11-viro@ZenIV.linux.org.uk
2017-06-14 00:00:43 +02:00
Al Viro 1acbe7708b posix-timers: Take compat timer_settime(2) to native one
... and get rid of set_fs() in there

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-10-viro@ZenIV.linux.org.uk
2017-06-14 00:00:43 +02:00
Al Viro 3a4d44b616 ntp: Move adjtimex related compat syscalls to native counterparts
Get rid of set_fs() mess and sanitize compat_{get,put}_timex(),
while we are at it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-9-viro@ZenIV.linux.org.uk
2017-06-14 00:00:43 +02:00
Al Viro edbeda4632 time/posix-timers: Move the compat copyouts to the nanosleep implementations
Turn restart_block.nanosleep.{rmtp,compat_rmtp} into a tagged union (kind =
1 -> native, kind = 2 -> compat, kind = 0 -> nothing) and make the places
doing actual copyout handle compat as well as native (that will become a
helper in the next commit).  Result: compat wrappers, messing with
reassignments, etc. are gone.

[ tglx: Folded in a variant of Peter Zijlstras enum patch ]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-6-viro@ZenIV.linux.org.uk
2017-06-14 00:00:42 +02:00
Al Viro 192a82f900 hrtimer_nanosleep(): Pass rmtp in restart_block
Store the pointer to the timespec which gets updated with the remaining
time in the restart block and remove the function argument.

[ tglx: Added changelog ]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-3-viro@ZenIV.linux.org.uk
2017-06-14 00:00:40 +02:00
Al Viro 1b3c872c83 rt_sigtimedwait(): move compat to native
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-09 23:57:12 -04:00
Al Viro 7668b679c3 put_compat_rusage(): switch to copy_to_user()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-09 23:56:13 -04:00
Al Viro 8f13621abc sigpending(): move compat to native
... and kill set_fs() use

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-09 23:51:38 -04:00
Al Viro d9e968cb9f getrlimit()/setrlimit(): move compat to native
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-09 23:51:33 -04:00
Al Viro ca2406ed58 times(2): move compat to native
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-09 23:51:28 -04:00
Al Viro 1e1fc13348 compat_{get,put}_bitmap(): use unsafe_{get,put}_user()
unroll the inner loops, while we are at it

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-09 23:51:17 -04:00
Al Viro 613763a1f0 take compat_sys_old_getrlimit() to native syscall
... and sanitize the ifdefs in there

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-05-27 15:38:06 -04:00
Al Viro 7e95a22590 move compat wait4 and waitid next to native variants
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-05-21 13:10:51 -04:00
Deepa Dinamani ad19638463 time: Change k_clock nsleep() to use timespec64
struct timespec is not y2038 safe on 32 bit machines.  Replace uses of
struct timespec with struct timespec64 in the kernel.

The syscall interfaces themselves will be changed in a separate series.

Note that the restart_block parameter for nanosleep has also been left
unchanged and will be part of syscall series noted above.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: y2038@lists.linaro.org
Cc: john.stultz@linaro.org
Cc: arnd@arndb.de
Link: http://lkml.kernel.org/r/1490555058-4603-8-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-14 21:49:56 +02:00
Deepa Dinamani 2ac00f17b2 time: Delete do_sys_setimeofday()
struct timespec is not y2038 safe on 32 bit machines and needs to be
replaced with struct timespec64.

do_sys_timeofday() is just a wrapper function.  Replace all calls to this
function with direct calls to do_sys_timeofday64() instead and delete
do_sys_timeofday().

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: y2038@lists.linaro.org
Cc: john.stultz@linaro.org
Cc: arnd@arndb.de
Cc: linux-alpha@vger.kernel.org
Link: http://lkml.kernel.org/r/1490555058-4603-2-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-14 21:49:54 +02:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Nicolas Pitre baa73d9e47 posix-timers: Make them configurable
Some embedded systems have no use for them.  This removes about
25KB from the kernel binary size when configured out.

Corresponding syscalls are routed to a stub logging the attempt to
use those syscalls which should be enough of a clue if they were
disabled without proper consideration. They are: timer_create,
timer_gettime: timer_getoverrun, timer_settime, timer_delete,
clock_adjtime, setitimer, getitimer, alarm.

The clock_settime, clock_gettime, clock_getres and clock_nanosleep
syscalls are replaced by simple wrappers compatible with CLOCK_REALTIME,
CLOCK_MONOTONIC and CLOCK_BOOTTIME only which should cover the vast
majority of use cases with very little code.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: linux-kbuild@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: Michal Marek <mmarek@suse.com>
Cc: Edward Cree <ecree@solarflare.com>
Link: http://lkml.kernel.org/r/1478841010-28605-7-git-send-email-nicolas.pitre@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 09:26:35 +01:00
Helge Deller 9b7b819ca1 compat: cleanup coding in compat_get_bitmap() and compat_put_bitmap()
In the functions compat_get_bitmap() and compat_put_bitmap() the
variable nr_compat_longs stores how many compat_ulong_t words should be
copied in a loop.

The copy loop itself is this:
  if (nr_compat_longs-- > 0) {
      if (__get_user(um, umask)) return -EFAULT;
  } else {
      um = 0;
  }

Since nr_compat_longs gets unconditionally decremented in each loop and
since it's type is unsigned this could theoretically lead to out of
bounds accesses to userspace if nr_compat_longs wraps around to
(unsigned)(-1).

Although the callers currently do not trigger out-of-bounds accesses, we
should better implement the loop in a safe way to completely avoid such
warp-arounds.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
2015-06-04 23:57:18 +02:00
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
Thomas Gleixner 849151dd54 compat: nanosleep: Clarify error handling
The error handling in compat_sys_nanosleep() is correct, but
completely non obvious. Document it and restrict it to the
-ERESTART_RESTARTBLOCK return value for clarity.

Reported-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-09-06 12:58:18 +02:00
Fabian Frederick 6516a46619 kernel/compat.c: use sizeof() instead of sizeof
Fix 4 checkpatch warnings
WARNING: sizeof *tv should be sizeof(*tv)

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:54:19 -07:00
Linus Torvalds 7125764c5d Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull compat time conversion changes from Peter Anvin:
 "Despite the branch name this is really neither an x86 nor an
  x32-specific patchset, although it the implementation of the
  discussions that followed the x32 security hole a few months ago.

  This removes get/put_compat_timespec/val() and replaces them with
  compat_get/put_timespec/val() which are savvy as to the current status
  of COMPAT_USE_64BIT_TIME.

  It removes several unused and/or incorrect/misleading functions (like
  compat_put_timeval_convert which doesn't in fact do any conversion)
  and also replaces several open-coded implementations what is now
  called compat_convert_timespec() with that function"

* 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  compat: Fix sparse address space warnings
  compat: Get rid of (get|put)_compat_time(val|spec)
2014-04-02 12:51:41 -07:00