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  1. 15 1月, 2019 2 次提交
  3. 10 1月, 2019 1 次提交
  5. 07 1月, 2019 1 次提交
  7. 05 1月, 2019 3 次提交
    • L
      make 'user_access_begin()' do 'access_ok()' · 594cc251
      由 Linus Torvalds 提交于 
      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: NLinus Torvalds <torvalds@linux-foundation.org>
      594cc251
    • L
      i915: fix missing user_access_end() in page fault exception case · 0b2c8f8b
      由 Linus Torvalds 提交于 
      When commit fddcd00a ("drm/i915: Force the slow path after a
user-write error") unified the error handling for various user access
problems, it didn't do the user_access_end() that is needed for the
unsafe_put_user() case.

It's not a huge deal: a missed user_access_end() will only mean that
SMAP protection isn't active afterwards, and for the error case we'll be
returning to user mode soon enough anyway.  But it's wrong, and adding
the proper user_access_end() is trivial enough (and doing it for the
other error cases where it isn't needed doesn't hurt).

I noticed it while doing the same prep-work for changing
user_access_begin() that precipitated the access_ok() changes in commit
96d4f267 ("Remove 'type' argument from access_ok() function").

Fixes: fddcd00a ("drm/i915: Force the slow path after a user-write error")
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: stable@kernel.org # v4.20
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      0b2c8f8b
    • J
      drm/tilcdc: Register cpufreq notifier after we have initialized crtc · 432973fd
      由 Jyri Sarha 提交于 
      Register cpufreq notifier after we have initialized the crtc and
unregister it before we remove the ctrc. Receiving a cpufreq notify
without crtc causes a crash.
Reported-by: NPeter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: NJyri Sarha <jsarha@ti.com>
      432973fd
  9. 04 1月, 2019 1 次提交
    • L
      Remove 'type' argument from access_ok() function · 96d4f267
      由 Linus Torvalds 提交于 
      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: NLinus Torvalds <torvalds@linux-foundation.org>
      96d4f267
  11. 03 1月, 2019 2 次提交
    • C
      drm: Reorder set_property_atomic to avoid returning with an active ww_ctx · 227ad6d9
      由 Chris Wilson 提交于 
      Delay the drm_modeset_acquire_init() until after we check for an
allocation failure so that we can return immediately upon error without
having to unwind.

WARNING: lock held when returning to user space!
4.20.0+ #174 Not tainted
------------------------------------------------
syz-executor556/8153 is leaving the kernel with locks still held!
1 lock held by syz-executor556/8153:
  #0: 000000005100c85c (crtc_ww_class_acquire){+.+.}, at:
set_property_atomic+0xb3/0x330 drivers/gpu/drm/drm_mode_object.c:462

Reported-by: syzbot+6ea337c427f5083ebdf2@syzkaller.appspotmail.com
Fixes: 144a7999 ("drm: Handle properties in the core for atomic drivers")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: <stable@vger.kernel.org> # v4.14+
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181230122842.21917-1-chris@chris-wilson.co.uk
      227ad6d9
    • B
      drm/nouveau: fix incorrect FB_BACKLIGHT usage in Kconfig · 399382f8
      由 Bartlomiej Zolnierkiewicz 提交于 
      Making FB_BACKLIGHT tristate by commit b4a1ed0c ("fbdev:
make FB_BACKLIGHT a tristate") caused unmet dependencies in
some configurations:

WARNING: unmet direct dependencies detected for FB_BACKLIGHT
  Depends on [m]: HAS_IOMEM [=y] && FB [=m]
  Selected by [y]:
  - DRM_NOUVEAU [=y] && HAS_IOMEM [=y] && DRM [=y] && PCI [=y] && MMU [=y] && DRM_NOUVEAU_BACKLIGHT [=y]
  Selected by [m]:
  - FB_NVIDIA [=m] && HAS_IOMEM [=y] && FB [=m] && PCI [=y] && FB_NVIDIA_BACKLIGHT [=y]

Fix it by making DRM_NOUVEAU select BACKLIGHT_CLASS_DEVICE and
BACKLIGHT_LCD_SUPPORT instead of FB_BACKLIGHT.

Fixes: b4a1ed0c ("fbdev: make FB_BACKLIGHT a tristate")
Reported-by: NRandy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Cc: Rob Clark <robdclark@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
      399382f8
  13. 02 1月, 2019 1 次提交
  15. 29 12月, 2018 3 次提交
  17. 27 12月, 2018 2 次提交
  19. 24 12月, 2018 2 次提交
  21. 22 12月, 2018 3 次提交
  23. 21 12月, 2018 9 次提交
  25. 20 12月, 2018 2 次提交
  27. 19 12月, 2018 8 次提交