linux-stable.git/drivers/gpu/drm, branch v5.4.56

drm: hold gem reference until object is no longer accessed

2020-08-05T07:59:44+00:00

commit 8490d6a7e0a0a6fab5c2d82d57a3937306660864 upstream.

A use-after-free in drm_gem_open_ioctl can happen if the
GEM object handle is closed between the idr lookup and
retrieving the size from said object since a local reference
is not being held at that point. Hold the local reference
while the object can still be accessed to fix this and
plug the potential security hole.

Signed-off-by: Steve Cohen 
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/1595284250-31580-1-git-send-email-cohens@codeaurora.org
Signed-off-by: Greg Kroah-Hartman

drm/dbi: Fix SPI Type 1 (9-bit) transfer

2020-08-05T07:59:44+00:00

commit 900ab59e2621053b009f707f80b2c19ce0af5dee upstream.

The function mipi_dbi_spi1_transfer() will transfer its payload as 9-bit
data, the 9th (MSB) bit being the data/command bit. In order to do that,
it unpacks the 8-bit values into 16-bit values, then sets the 9th bit if
the byte corresponds to data, clears it otherwise. The 7 MSB are
padding. The array of now 16-bit values is then passed to the SPI core
for transfer.

This function was broken since its introduction, as the length of the
SPI transfer was set to the payload size before its conversion, but the
payload doubled in size due to the 8-bit -> 16-bit conversion.

Fixes: 02dd95fe3169 ("drm/tinydrm: Add MIPI DBI support")
Cc:  # 5.4+
Signed-off-by: Paul Cercueil 
Reviewed-by: Sam Ravnborg 
Reviewed-by: Noralf Trønnes 
Signed-off-by: Sam Ravnborg 
Link: https://patchwork.freedesktop.org/patch/msgid/20200703141341.1266263-1-paul@crapouillou.net
Signed-off-by: Greg Kroah-Hartman

drm/amdgpu: Prevent kernel-infoleak in amdgpu_info_ioctl()

2020-08-05T07:59:43+00:00

commit 543e8669ed9bfb30545fd52bc0e047ca4df7fb31 upstream.

Compiler leaves a 4-byte hole near the end of `dev_info`, causing
amdgpu_info_ioctl() to copy uninitialized kernel stack memory to userspace
when `size` is greater than 356.

In 2015 we tried to fix this issue by doing `= {};` on `dev_info`, which
unfortunately does not initialize that 4-byte hole. Fix it by using
memset() instead.

Cc: stable@vger.kernel.org
Fixes: c193fa91b918 ("drm/amdgpu: information leak in amdgpu_info_ioctl()")
Fixes: d38ceaf99ed0 ("drm/amdgpu: add core driver (v4)")
Suggested-by: Dan Carpenter 
Reviewed-by: Christian König 
Signed-off-by: Peilin Ye 
Signed-off-by: Alex Deucher 
Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Clear dm_state for fast updates

2020-08-05T07:59:43+00:00

commit fde9f39ac7f1ffd799a96ffa1e06b2051f0898f1 upstream.

This patch fixes a race condition that causes a use-after-free during
amdgpu_dm_atomic_commit_tail. This can occur when 2 non-blocking commits
are requested and the second one finishes before the first. Essentially,
this bug occurs when the following sequence of events happens:

1. Non-blocking commit #1 is requested w/ a new dm_state #1 and is
deferred to the workqueue.

2. Non-blocking commit #2 is requested w/ a new dm_state #2 and is
deferred to the workqueue.

3. Commit #2 starts before commit #1, dm_state #1 is used in the
commit_tail and commit #2 completes, freeing dm_state #1.

4. Commit #1 starts after commit #2 completes, uses the freed dm_state
1 and dereferences a freelist pointer while setting the context.

Since this bug has only been spotted with fast commits, this patch fixes
the bug by clearing the dm_state instead of using the old dc_state for
fast updates. In addition, since dm_state is only used for its dc_state
and amdgpu_dm_atomic_commit_tail will retain the dc_state if none is found,
removing the dm_state should not have any consequences in fast updates.

This use-after-free bug has existed for a while now, but only caused a
noticeable issue starting from 5.7-rc1 due to 3202fa62f ("slub: relocate
freelist pointer to middle of object") moving the freelist pointer from
dm_state->base (which was unused) to dm_state->context (which is
dereferenced).

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=207383
Fixes: bd200d190f45 ("drm/amd/display: Don't replace the dc_state for fast updates")
Reported-by: Duncan <1i5t5.duncan@cox.net>
Signed-off-by: Mazin Rezk 
Reviewed-by: Nicholas Kazlauskas 
Signed-off-by: Alex Deucher 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

Revert "drm/amdgpu: Fix NULL dereference in dpm sysfs handlers"

2020-08-05T07:59:43+00:00

commit 87004abfbc27261edd15716515d89ab42198b405 upstream.

This regressed some working configurations so revert it.  Will
fix this properly for 5.9 and backport then.

This reverts commit 38e0c89a19fd13f28d2b4721035160a3e66e270b.

Signed-off-by: Alex Deucher 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

drm/amd/powerplay: fix a crash when overclocking Vega M

2020-07-29T08:18:44+00:00

commit 88bb16ad998a0395fe4b346b7d3f621aaa0a2324 upstream.

Avoid kernel crash when vddci_control is SMU7_VOLTAGE_CONTROL_NONE and
vddci_voltage_table is empty. It has been tested on Intel Hades Canyon
(i7-8809G).

Bug: https://bugzilla.kernel.org/show_bug.cgi?id=208489
Fixes: ac7822b0026f ("drm/amd/powerplay: add smumgr support for VEGAM (v2)")
Reviewed-by: Evan Quan 
Signed-off-by: Qiu Wenbo 
Signed-off-by: Alex Deucher 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

drm/amdgpu: Fix NULL dereference in dpm sysfs handlers

2020-07-29T08:18:44+00:00

commit 38e0c89a19fd13f28d2b4721035160a3e66e270b upstream.

NULL dereference occurs when string that is not ended with space or
newline is written to some dpm sysfs interface (for example pp_dpm_sclk).
This happens because strsep replaces the tmp with NULL if the delimiter
is not present in string, which is then dereferenced by tmp[0].

Reproduction example:
sudo sh -c 'echo -n 1 > /sys/class/drm/card0/device/pp_dpm_sclk'

Signed-off-by: Paweł Gronowski 
Signed-off-by: Alex Deucher 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

drm/amdgpu: fix preemption unit test

2020-07-29T08:18:39+00:00

[ Upstream commit d845a2051b6b673fab4229b920ea04c7c4352b51 ]

Remove signaled jobs from job list and ensure the
job was indeed preempted.

Signed-off-by: Jack Xiao 
Reviewed-by: Hawking Zhang 
Signed-off-by: Alex Deucher 
Signed-off-by: Sasha Levin

drm/amdgpu/gfx10: fix race condition for kiq

2020-07-29T08:18:39+00:00

[ Upstream commit 7d65a577bb58d4f27a3398a4c0cb0b00ab7d0511 ]

During preemption test for gfx10, it uses kiq to trigger
gfx preemption, which would result in race condition
with flushing TLB for kiq.

Signed-off-by: Jack Xiao 
Reviewed-by: Hawking Zhang 
Acked-by: Christian König 
Signed-off-by: Alex Deucher 
Signed-off-by: Sasha Levin

drm: sun4i: hdmi: Fix inverted HPD result

2020-07-29T08:18:32+00:00

[ Upstream commit baa1841eb797eadce6c907bdaed7cd6f01815404 ]

When the extra HPD polling in sun4i_hdmi was removed, the result of
HPD was accidentally inverted.

Fix this by inverting the check.

Fixes: bda8eaa6dee7 ("drm: sun4i: hdmi: Remove extra HPD polling")
Signed-off-by: Chen-Yu Tsai 
Tested-by: Mans Rullgard 
Signed-off-by: Maxime Ripard 
Link: https://patchwork.freedesktop.org/patch/msgid/20200711011030.21997-1-wens@kernel.org
Signed-off-by: Sasha Levin