<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/video, branch v5.4.161</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>video: backlight: Drop maximum brightness override for brightness zero</title>
<updated>2021-11-17T08:48:50+00:00</updated>
<author>
<name>Marek Vasut</name>
<email>marex@denx.de</email>
</author>
<published>2021-09-21T17:35:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b0989ae51d01b2e86840bed7cd7ca7cc8395c6ca'/>
<id>b0989ae51d01b2e86840bed7cd7ca7cc8395c6ca</id>
<content type='text'>
commit 33a5471f8da976bf271a1ebbd6b9d163cb0cb6aa upstream.

The note in c2adda27d202f ("video: backlight: Add of_find_backlight helper
in backlight.c") says that gpio-backlight uses brightness as power state.
This has been fixed since in ec665b756e6f7 ("backlight: gpio-backlight:
Correct initial power state handling") and other backlight drivers do not
require this workaround. Drop the workaround.

This fixes the case where e.g. pwm-backlight can perfectly well be set to
brightness 0 on boot in DT, which without this patch leads to the display
brightness to be max instead of off.

Fixes: c2adda27d202f ("video: backlight: Add of_find_backlight helper in backlight.c")
Cc: &lt;stable@vger.kernel.org&gt; # 5.4+
Cc: &lt;stable@vger.kernel.org&gt; # 4.19.x: ec665b756e6f7: backlight: gpio-backlight: Correct initial power state handling
Signed-off-by: Marek Vasut &lt;marex@denx.de&gt;
Acked-by: Noralf Trønnes &lt;noralf@tronnes.org&gt;
Reviewed-by: Daniel Thompson &lt;daniel.thompson@linaro.org&gt;
Signed-off-by: Lee Jones &lt;lee.jones@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 33a5471f8da976bf271a1ebbd6b9d163cb0cb6aa upstream.

The note in c2adda27d202f ("video: backlight: Add of_find_backlight helper
in backlight.c") says that gpio-backlight uses brightness as power state.
This has been fixed since in ec665b756e6f7 ("backlight: gpio-backlight:
Correct initial power state handling") and other backlight drivers do not
require this workaround. Drop the workaround.

This fixes the case where e.g. pwm-backlight can perfectly well be set to
brightness 0 on boot in DT, which without this patch leads to the display
brightness to be max instead of off.

Fixes: c2adda27d202f ("video: backlight: Add of_find_backlight helper in backlight.c")
Cc: &lt;stable@vger.kernel.org&gt; # 5.4+
Cc: &lt;stable@vger.kernel.org&gt; # 4.19.x: ec665b756e6f7: backlight: gpio-backlight: Correct initial power state handling
Signed-off-by: Marek Vasut &lt;marex@denx.de&gt;
Acked-by: Noralf Trønnes &lt;noralf@tronnes.org&gt;
Reviewed-by: Daniel Thompson &lt;daniel.thompson@linaro.org&gt;
Signed-off-by: Lee Jones &lt;lee.jones@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>video: fbdev: chipsfb: use memset_io() instead of memset()</title>
<updated>2021-11-17T08:48:42+00:00</updated>
<author>
<name>Christophe Leroy</name>
<email>christophe.leroy@csgroup.eu</email>
</author>
<published>2021-09-15T13:34:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d8241e7a214449fc332d78fa839775134a5b13ef'/>
<id>d8241e7a214449fc332d78fa839775134a5b13ef</id>
<content type='text'>
[ Upstream commit f2719b26ae27282c145202ffd656d5ff1fe737cc ]

While investigating a lockup at startup on Powerbook 3400C, it was
identified that the fbdev driver generates alignment exception at
startup:

  --- interrupt: 600 at memset+0x60/0xc0
  NIP:  c0021414 LR: c03fc49c CTR: 00007fff
  REGS: ca021c10 TRAP: 0600   Tainted: G        W          (5.14.2-pmac-00727-g12a41fa69492)
  MSR:  00009032 &lt;EE,ME,IR,DR,RI&gt;  CR: 44008442  XER: 20000100
  DAR: cab80020 DSISR: 00017c07
  GPR00: 00000007 ca021cd0 c14412e0 cab80000 00000000 00100000 cab8001c 00000004
  GPR08: 00100000 00007fff 00000000 00000000 84008442 00000000 c0006fb4 00000000
  GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00100000
  GPR24: 00000000 81800000 00000320 c15fa400 c14d1878 00000000 c14d1800 c094e19c
  NIP [c0021414] memset+0x60/0xc0
  LR [c03fc49c] chipsfb_pci_init+0x160/0x580
  --- interrupt: 600
  [ca021cd0] [c03fc46c] chipsfb_pci_init+0x130/0x580 (unreliable)
  [ca021d20] [c03a3a70] pci_device_probe+0xf8/0x1b8
  [ca021d50] [c043d584] really_probe.part.0+0xac/0x388
  [ca021d70] [c043d914] __driver_probe_device+0xb4/0x170
  [ca021d90] [c043da18] driver_probe_device+0x48/0x144
  [ca021dc0] [c043e318] __driver_attach+0x11c/0x1c4
  [ca021de0] [c043ad30] bus_for_each_dev+0x88/0xf0
  [ca021e10] [c043c724] bus_add_driver+0x190/0x22c
  [ca021e40] [c043ee94] driver_register+0x9c/0x170
  [ca021e60] [c0006c28] do_one_initcall+0x54/0x1ec
  [ca021ed0] [c08246e4] kernel_init_freeable+0x1c0/0x270
  [ca021f10] [c0006fdc] kernel_init+0x28/0x11c
  [ca021f30] [c0017148] ret_from_kernel_thread+0x14/0x1c
  Instruction dump:
  7d4601a4 39490777 7d4701a4 39490888 7d4801a4 39490999 7d4901a4 39290aaa
  7d2a01a4 4c00012c 4bfffe88 0fe00000 &lt;4bfffe80&gt; 9421fff0 38210010 48001970

This is due to 'dcbz' instruction being used on non-cached memory.
'dcbz' instruction is used by memset() to zeroize a complete
cacheline at once, and memset() is not expected to be used on non
cached memory.

When performing a 'sparse' check on fbdev driver, it also appears
that the use of memset() is unexpected:

  drivers/video/fbdev/chipsfb.c:334:17: warning: incorrect type in argument 1 (different address spaces)
  drivers/video/fbdev/chipsfb.c:334:17:    expected void *
  drivers/video/fbdev/chipsfb.c:334:17:    got char [noderef] __iomem *screen_base
  drivers/video/fbdev/chipsfb.c:334:15: warning: memset with byte count of 1048576

Use fb_memset() instead of memset(). fb_memset() is defined as
memset_io() for powerpc.

Fixes: 8c8709334cec ("[PATCH] ppc32: Remove CONFIG_PMAC_PBOOK")
Reported-by: Stan Johnson &lt;userm57@yahoo.com&gt;
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/884a54f1e5cb774c1d9b4db780209bee5d4f6718.1631712563.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit f2719b26ae27282c145202ffd656d5ff1fe737cc ]

While investigating a lockup at startup on Powerbook 3400C, it was
identified that the fbdev driver generates alignment exception at
startup:

  --- interrupt: 600 at memset+0x60/0xc0
  NIP:  c0021414 LR: c03fc49c CTR: 00007fff
  REGS: ca021c10 TRAP: 0600   Tainted: G        W          (5.14.2-pmac-00727-g12a41fa69492)
  MSR:  00009032 &lt;EE,ME,IR,DR,RI&gt;  CR: 44008442  XER: 20000100
  DAR: cab80020 DSISR: 00017c07
  GPR00: 00000007 ca021cd0 c14412e0 cab80000 00000000 00100000 cab8001c 00000004
  GPR08: 00100000 00007fff 00000000 00000000 84008442 00000000 c0006fb4 00000000
  GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00100000
  GPR24: 00000000 81800000 00000320 c15fa400 c14d1878 00000000 c14d1800 c094e19c
  NIP [c0021414] memset+0x60/0xc0
  LR [c03fc49c] chipsfb_pci_init+0x160/0x580
  --- interrupt: 600
  [ca021cd0] [c03fc46c] chipsfb_pci_init+0x130/0x580 (unreliable)
  [ca021d20] [c03a3a70] pci_device_probe+0xf8/0x1b8
  [ca021d50] [c043d584] really_probe.part.0+0xac/0x388
  [ca021d70] [c043d914] __driver_probe_device+0xb4/0x170
  [ca021d90] [c043da18] driver_probe_device+0x48/0x144
  [ca021dc0] [c043e318] __driver_attach+0x11c/0x1c4
  [ca021de0] [c043ad30] bus_for_each_dev+0x88/0xf0
  [ca021e10] [c043c724] bus_add_driver+0x190/0x22c
  [ca021e40] [c043ee94] driver_register+0x9c/0x170
  [ca021e60] [c0006c28] do_one_initcall+0x54/0x1ec
  [ca021ed0] [c08246e4] kernel_init_freeable+0x1c0/0x270
  [ca021f10] [c0006fdc] kernel_init+0x28/0x11c
  [ca021f30] [c0017148] ret_from_kernel_thread+0x14/0x1c
  Instruction dump:
  7d4601a4 39490777 7d4701a4 39490888 7d4801a4 39490999 7d4901a4 39290aaa
  7d2a01a4 4c00012c 4bfffe88 0fe00000 &lt;4bfffe80&gt; 9421fff0 38210010 48001970

This is due to 'dcbz' instruction being used on non-cached memory.
'dcbz' instruction is used by memset() to zeroize a complete
cacheline at once, and memset() is not expected to be used on non
cached memory.

When performing a 'sparse' check on fbdev driver, it also appears
that the use of memset() is unexpected:

  drivers/video/fbdev/chipsfb.c:334:17: warning: incorrect type in argument 1 (different address spaces)
  drivers/video/fbdev/chipsfb.c:334:17:    expected void *
  drivers/video/fbdev/chipsfb.c:334:17:    got char [noderef] __iomem *screen_base
  drivers/video/fbdev/chipsfb.c:334:15: warning: memset with byte count of 1048576

Use fb_memset() instead of memset(). fb_memset() is defined as
memset_io() for powerpc.

Fixes: 8c8709334cec ("[PATCH] ppc32: Remove CONFIG_PMAC_PBOOK")
Reported-by: Stan Johnson &lt;userm57@yahoo.com&gt;
Signed-off-by: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Link: https://lore.kernel.org/r/884a54f1e5cb774c1d9b4db780209bee5d4f6718.1631712563.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>video: fbdev: gbefb: Only instantiate device when built for IP32</title>
<updated>2021-10-13T08:08:19+00:00</updated>
<author>
<name>Mark Brown</name>
<email>broonie@kernel.org</email>
</author>
<published>2021-09-21T21:21:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cb7e651879839eae28a373b49a1e06b432c82a62'/>
<id>cb7e651879839eae28a373b49a1e06b432c82a62</id>
<content type='text'>
[ Upstream commit 11b8e2bb986d23157e82e267fb8cc6b281dfdee9 ]

The gbefb driver not only registers a driver but also the device for that
driver. This is all well and good when run on the IP32 machines that are
supported by the driver but since the driver supports building with
COMPILE_TEST we might also be building on other platforms which do not have
this hardware and will crash instantiating the driver. Add an IS_ENABLED()
check so we compile out the device registration if we don't have the Kconfig
option for the machine enabled.

Fixes: 552ccf6b259d290c0c ("video: fbdev: gbefb: add COMPILE_TEST support")
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Cc: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20210921212102.30803-1-broonie@kernel.org
Signed-off-by: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 11b8e2bb986d23157e82e267fb8cc6b281dfdee9 ]

The gbefb driver not only registers a driver but also the device for that
driver. This is all well and good when run on the IP32 machines that are
supported by the driver but since the driver supports building with
COMPILE_TEST we might also be building on other platforms which do not have
this hardware and will crash instantiating the driver. Add an IS_ENABLED()
check so we compile out the device registration if we don't have the Kconfig
option for the machine enabled.

Fixes: 552ccf6b259d290c0c ("video: fbdev: gbefb: add COMPILE_TEST support")
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Cc: Bartlomiej Zolnierkiewicz &lt;b.zolnierkie@samsung.com&gt;
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20210921212102.30803-1-broonie@kernel.org
Signed-off-by: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>video: fbdev: riva: Error out if 'pixclock' equals zero</title>
<updated>2021-09-22T10:26:29+00:00</updated>
<author>
<name>Zheyu Ma</name>
<email>zheyuma97@gmail.com</email>
</author>
<published>2021-07-26T10:03:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=faf0749c9062469631c26bbdc9d1d568d1241224'/>
<id>faf0749c9062469631c26bbdc9d1d568d1241224</id>
<content type='text'>
[ Upstream commit f92763cb0feba247e0939ed137b495601fd072a5 ]

The userspace program could pass any values to the driver through
ioctl() interface. If the driver doesn't check the value of 'pixclock',
it may cause divide error.

Fix this by checking whether 'pixclock' is zero first.

The following log reveals it:

[   33.396850] divide error: 0000 [#1] PREEMPT SMP KASAN PTI
[   33.396864] CPU: 5 PID: 11754 Comm: i740 Not tainted 5.14.0-rc2-00513-gac532c9bbcfb-dirty #222
[   33.396883] RIP: 0010:riva_load_video_mode+0x417/0xf70
[   33.396969] Call Trace:
[   33.396973]  ? debug_smp_processor_id+0x1c/0x20
[   33.396984]  ? tick_nohz_tick_stopped+0x1a/0x90
[   33.396996]  ? rivafb_copyarea+0x3c0/0x3c0
[   33.397003]  ? wake_up_klogd.part.0+0x99/0xd0
[   33.397014]  ? vprintk_emit+0x110/0x4b0
[   33.397024]  ? vprintk_default+0x26/0x30
[   33.397033]  ? vprintk+0x9c/0x1f0
[   33.397041]  ? printk+0xba/0xed
[   33.397054]  ? record_print_text.cold+0x16/0x16
[   33.397063]  ? __kasan_check_read+0x11/0x20
[   33.397074]  ? profile_tick+0xc0/0x100
[   33.397084]  ? __sanitizer_cov_trace_const_cmp4+0x24/0x80
[   33.397094]  ? riva_set_rop_solid+0x2a0/0x2a0
[   33.397102]  rivafb_set_par+0xbe/0x610
[   33.397111]  ? riva_set_rop_solid+0x2a0/0x2a0
[   33.397119]  fb_set_var+0x5bf/0xeb0
[   33.397127]  ? fb_blank+0x1a0/0x1a0
[   33.397134]  ? lock_acquire+0x1ef/0x530
[   33.397143]  ? lock_release+0x810/0x810
[   33.397151]  ? lock_is_held_type+0x100/0x140
[   33.397159]  ? ___might_sleep+0x1ee/0x2d0
[   33.397170]  ? __mutex_lock+0x620/0x1190
[   33.397180]  ? trace_hardirqs_on+0x6a/0x1c0
[   33.397190]  do_fb_ioctl+0x31e/0x700

Signed-off-by: Zheyu Ma &lt;zheyuma97@gmail.com&gt;
Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1627293835-17441-4-git-send-email-zheyuma97@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit f92763cb0feba247e0939ed137b495601fd072a5 ]

The userspace program could pass any values to the driver through
ioctl() interface. If the driver doesn't check the value of 'pixclock',
it may cause divide error.

Fix this by checking whether 'pixclock' is zero first.

The following log reveals it:

[   33.396850] divide error: 0000 [#1] PREEMPT SMP KASAN PTI
[   33.396864] CPU: 5 PID: 11754 Comm: i740 Not tainted 5.14.0-rc2-00513-gac532c9bbcfb-dirty #222
[   33.396883] RIP: 0010:riva_load_video_mode+0x417/0xf70
[   33.396969] Call Trace:
[   33.396973]  ? debug_smp_processor_id+0x1c/0x20
[   33.396984]  ? tick_nohz_tick_stopped+0x1a/0x90
[   33.396996]  ? rivafb_copyarea+0x3c0/0x3c0
[   33.397003]  ? wake_up_klogd.part.0+0x99/0xd0
[   33.397014]  ? vprintk_emit+0x110/0x4b0
[   33.397024]  ? vprintk_default+0x26/0x30
[   33.397033]  ? vprintk+0x9c/0x1f0
[   33.397041]  ? printk+0xba/0xed
[   33.397054]  ? record_print_text.cold+0x16/0x16
[   33.397063]  ? __kasan_check_read+0x11/0x20
[   33.397074]  ? profile_tick+0xc0/0x100
[   33.397084]  ? __sanitizer_cov_trace_const_cmp4+0x24/0x80
[   33.397094]  ? riva_set_rop_solid+0x2a0/0x2a0
[   33.397102]  rivafb_set_par+0xbe/0x610
[   33.397111]  ? riva_set_rop_solid+0x2a0/0x2a0
[   33.397119]  fb_set_var+0x5bf/0xeb0
[   33.397127]  ? fb_blank+0x1a0/0x1a0
[   33.397134]  ? lock_acquire+0x1ef/0x530
[   33.397143]  ? lock_release+0x810/0x810
[   33.397151]  ? lock_is_held_type+0x100/0x140
[   33.397159]  ? ___might_sleep+0x1ee/0x2d0
[   33.397170]  ? __mutex_lock+0x620/0x1190
[   33.397180]  ? trace_hardirqs_on+0x6a/0x1c0
[   33.397190]  do_fb_ioctl+0x31e/0x700

Signed-off-by: Zheyu Ma &lt;zheyuma97@gmail.com&gt;
Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1627293835-17441-4-git-send-email-zheyuma97@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>video: fbdev: kyro: Error out if 'pixclock' equals zero</title>
<updated>2021-09-22T10:26:29+00:00</updated>
<author>
<name>Zheyu Ma</name>
<email>zheyuma97@gmail.com</email>
</author>
<published>2021-07-26T10:03:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ae0d210aa717b480ca9f6337ec079f8c6913a04c'/>
<id>ae0d210aa717b480ca9f6337ec079f8c6913a04c</id>
<content type='text'>
[ Upstream commit 1520b4b7ba964f8eec2e7dd14c571d50de3e5191 ]

The userspace program could pass any values to the driver through
ioctl() interface. if the driver doesn't check the value of 'pixclock',
it may cause divide error because the value of 'lineclock' and
'frameclock' will be zero.

Fix this by checking whether 'pixclock' is zero in kyrofb_check_var().

The following log reveals it:

[  103.073930] divide error: 0000 [#1] PREEMPT SMP KASAN PTI
[  103.073942] CPU: 4 PID: 12483 Comm: syz-executor Not tainted 5.14.0-rc2-00478-g2734d6c1b1a0-dirty #118
[  103.073959] RIP: 0010:kyrofb_set_par+0x316/0xc80
[  103.074045] Call Trace:
[  103.074048]  ? ___might_sleep+0x1ee/0x2d0
[  103.074060]  ? kyrofb_ioctl+0x330/0x330
[  103.074069]  fb_set_var+0x5bf/0xeb0
[  103.074078]  ? fb_blank+0x1a0/0x1a0
[  103.074085]  ? lock_acquire+0x3bd/0x530
[  103.074094]  ? lock_release+0x810/0x810
[  103.074103]  ? ___might_sleep+0x1ee/0x2d0
[  103.074114]  ? __mutex_lock+0x620/0x1190
[  103.074126]  ? trace_hardirqs_on+0x6a/0x1c0
[  103.074137]  do_fb_ioctl+0x31e/0x700
[  103.074144]  ? fb_getput_cmap+0x280/0x280
[  103.074152]  ? rcu_read_lock_sched_held+0x11/0x80
[  103.074162]  ? rcu_read_lock_sched_held+0x11/0x80
[  103.074171]  ? __sanitizer_cov_trace_switch+0x67/0xf0
[  103.074181]  ? __sanitizer_cov_trace_const_cmp2+0x20/0x80
[  103.074191]  ? do_vfs_ioctl+0x14b/0x16c0
[  103.074199]  ? vfs_fileattr_set+0xb60/0xb60
[  103.074207]  ? rcu_read_lock_sched_held+0x11/0x80
[  103.074216]  ? lock_release+0x483/0x810
[  103.074224]  ? __fget_files+0x217/0x3d0
[  103.074234]  ? __fget_files+0x239/0x3d0
[  103.074243]  ? do_fb_ioctl+0x700/0x700
[  103.074250]  fb_ioctl+0xe6/0x130

Signed-off-by: Zheyu Ma &lt;zheyuma97@gmail.com&gt;
Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1627293835-17441-3-git-send-email-zheyuma97@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1520b4b7ba964f8eec2e7dd14c571d50de3e5191 ]

The userspace program could pass any values to the driver through
ioctl() interface. if the driver doesn't check the value of 'pixclock',
it may cause divide error because the value of 'lineclock' and
'frameclock' will be zero.

Fix this by checking whether 'pixclock' is zero in kyrofb_check_var().

The following log reveals it:

[  103.073930] divide error: 0000 [#1] PREEMPT SMP KASAN PTI
[  103.073942] CPU: 4 PID: 12483 Comm: syz-executor Not tainted 5.14.0-rc2-00478-g2734d6c1b1a0-dirty #118
[  103.073959] RIP: 0010:kyrofb_set_par+0x316/0xc80
[  103.074045] Call Trace:
[  103.074048]  ? ___might_sleep+0x1ee/0x2d0
[  103.074060]  ? kyrofb_ioctl+0x330/0x330
[  103.074069]  fb_set_var+0x5bf/0xeb0
[  103.074078]  ? fb_blank+0x1a0/0x1a0
[  103.074085]  ? lock_acquire+0x3bd/0x530
[  103.074094]  ? lock_release+0x810/0x810
[  103.074103]  ? ___might_sleep+0x1ee/0x2d0
[  103.074114]  ? __mutex_lock+0x620/0x1190
[  103.074126]  ? trace_hardirqs_on+0x6a/0x1c0
[  103.074137]  do_fb_ioctl+0x31e/0x700
[  103.074144]  ? fb_getput_cmap+0x280/0x280
[  103.074152]  ? rcu_read_lock_sched_held+0x11/0x80
[  103.074162]  ? rcu_read_lock_sched_held+0x11/0x80
[  103.074171]  ? __sanitizer_cov_trace_switch+0x67/0xf0
[  103.074181]  ? __sanitizer_cov_trace_const_cmp2+0x20/0x80
[  103.074191]  ? do_vfs_ioctl+0x14b/0x16c0
[  103.074199]  ? vfs_fileattr_set+0xb60/0xb60
[  103.074207]  ? rcu_read_lock_sched_held+0x11/0x80
[  103.074216]  ? lock_release+0x483/0x810
[  103.074224]  ? __fget_files+0x217/0x3d0
[  103.074234]  ? __fget_files+0x239/0x3d0
[  103.074243]  ? do_fb_ioctl+0x700/0x700
[  103.074250]  fb_ioctl+0xe6/0x130

Signed-off-by: Zheyu Ma &lt;zheyuma97@gmail.com&gt;
Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1627293835-17441-3-git-send-email-zheyuma97@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>video: fbdev: asiliantfb: Error out if 'pixclock' equals zero</title>
<updated>2021-09-22T10:26:29+00:00</updated>
<author>
<name>Zheyu Ma</name>
<email>zheyuma97@gmail.com</email>
</author>
<published>2021-07-26T10:03:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=98551f0a7b57dd22d3349ec0424d566b2cd467c8'/>
<id>98551f0a7b57dd22d3349ec0424d566b2cd467c8</id>
<content type='text'>
[ Upstream commit b36b242d4b8ea178f7fd038965e3cac7f30c3f09 ]

The userspace program could pass any values to the driver through
ioctl() interface. If the driver doesn't check the value of 'pixclock',
it may cause divide error.

Fix this by checking whether 'pixclock' is zero first.

The following log reveals it:

[   43.861711] divide error: 0000 [#1] PREEMPT SMP KASAN PTI
[   43.861737] CPU: 2 PID: 11764 Comm: i740 Not tainted 5.14.0-rc2-00513-gac532c9bbcfb-dirty #224
[   43.861756] RIP: 0010:asiliantfb_check_var+0x4e/0x730
[   43.861843] Call Trace:
[   43.861848]  ? asiliantfb_remove+0x190/0x190
[   43.861858]  fb_set_var+0x2e4/0xeb0
[   43.861866]  ? fb_blank+0x1a0/0x1a0
[   43.861873]  ? lock_acquire+0x1ef/0x530
[   43.861884]  ? lock_release+0x810/0x810
[   43.861892]  ? lock_is_held_type+0x100/0x140
[   43.861903]  ? ___might_sleep+0x1ee/0x2d0
[   43.861914]  ? __mutex_lock+0x620/0x1190
[   43.861921]  ? do_fb_ioctl+0x313/0x700
[   43.861929]  ? mutex_lock_io_nested+0xfa0/0xfa0
[   43.861936]  ? __this_cpu_preempt_check+0x1d/0x30
[   43.861944]  ? _raw_spin_unlock_irqrestore+0x46/0x60
[   43.861952]  ? lockdep_hardirqs_on+0x59/0x100
[   43.861959]  ? _raw_spin_unlock_irqrestore+0x46/0x60
[   43.861967]  ? trace_hardirqs_on+0x6a/0x1c0
[   43.861978]  do_fb_ioctl+0x31e/0x700

Signed-off-by: Zheyu Ma &lt;zheyuma97@gmail.com&gt;
Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1627293835-17441-2-git-send-email-zheyuma97@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit b36b242d4b8ea178f7fd038965e3cac7f30c3f09 ]

The userspace program could pass any values to the driver through
ioctl() interface. If the driver doesn't check the value of 'pixclock',
it may cause divide error.

Fix this by checking whether 'pixclock' is zero first.

The following log reveals it:

[   43.861711] divide error: 0000 [#1] PREEMPT SMP KASAN PTI
[   43.861737] CPU: 2 PID: 11764 Comm: i740 Not tainted 5.14.0-rc2-00513-gac532c9bbcfb-dirty #224
[   43.861756] RIP: 0010:asiliantfb_check_var+0x4e/0x730
[   43.861843] Call Trace:
[   43.861848]  ? asiliantfb_remove+0x190/0x190
[   43.861858]  fb_set_var+0x2e4/0xeb0
[   43.861866]  ? fb_blank+0x1a0/0x1a0
[   43.861873]  ? lock_acquire+0x1ef/0x530
[   43.861884]  ? lock_release+0x810/0x810
[   43.861892]  ? lock_is_held_type+0x100/0x140
[   43.861903]  ? ___might_sleep+0x1ee/0x2d0
[   43.861914]  ? __mutex_lock+0x620/0x1190
[   43.861921]  ? do_fb_ioctl+0x313/0x700
[   43.861929]  ? mutex_lock_io_nested+0xfa0/0xfa0
[   43.861936]  ? __this_cpu_preempt_check+0x1d/0x30
[   43.861944]  ? _raw_spin_unlock_irqrestore+0x46/0x60
[   43.861952]  ? lockdep_hardirqs_on+0x59/0x100
[   43.861959]  ? _raw_spin_unlock_irqrestore+0x46/0x60
[   43.861967]  ? trace_hardirqs_on+0x6a/0x1c0
[   43.861978]  do_fb_ioctl+0x31e/0x700

Signed-off-by: Zheyu Ma &lt;zheyuma97@gmail.com&gt;
Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1627293835-17441-2-git-send-email-zheyuma97@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>video: fbdev: kyro: fix a DoS bug by restricting user input</title>
<updated>2021-09-22T10:26:27+00:00</updated>
<author>
<name>Zheyu Ma</name>
<email>zheyuma97@gmail.com</email>
</author>
<published>2021-07-14T04:09:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5adbbb27bb7ce6ad28d8f31232961630e4143811'/>
<id>5adbbb27bb7ce6ad28d8f31232961630e4143811</id>
<content type='text'>
[ Upstream commit 98a65439172dc69cb16834e62e852afc2adb83ed ]

The user can pass in any value to the driver through the 'ioctl'
interface. The driver dost not check, which may cause DoS bugs.

The following log reveals it:

divide error: 0000 [#1] PREEMPT SMP KASAN PTI
RIP: 0010:SetOverlayViewPort+0x133/0x5f0 drivers/video/fbdev/kyro/STG4000OverlayDevice.c:476
Call Trace:
 kyro_dev_overlay_viewport_set drivers/video/fbdev/kyro/fbdev.c:378 [inline]
 kyrofb_ioctl+0x2eb/0x330 drivers/video/fbdev/kyro/fbdev.c:603
 do_fb_ioctl+0x1f3/0x700 drivers/video/fbdev/core/fbmem.c:1171
 fb_ioctl+0xeb/0x130 drivers/video/fbdev/core/fbmem.c:1185
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x19b/0x220 fs/ioctl.c:739
 do_syscall_64+0x32/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Signed-off-by: Zheyu Ma &lt;zheyuma97@gmail.com&gt;
Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1626235762-2590-1-git-send-email-zheyuma97@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 98a65439172dc69cb16834e62e852afc2adb83ed ]

The user can pass in any value to the driver through the 'ioctl'
interface. The driver dost not check, which may cause DoS bugs.

The following log reveals it:

divide error: 0000 [#1] PREEMPT SMP KASAN PTI
RIP: 0010:SetOverlayViewPort+0x133/0x5f0 drivers/video/fbdev/kyro/STG4000OverlayDevice.c:476
Call Trace:
 kyro_dev_overlay_viewport_set drivers/video/fbdev/kyro/fbdev.c:378 [inline]
 kyrofb_ioctl+0x2eb/0x330 drivers/video/fbdev/kyro/fbdev.c:603
 do_fb_ioctl+0x1f3/0x700 drivers/video/fbdev/core/fbmem.c:1171
 fb_ioctl+0xeb/0x130 drivers/video/fbdev/core/fbmem.c:1185
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x19b/0x220 fs/ioctl.c:739
 do_syscall_64+0x32/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Signed-off-by: Zheyu Ma &lt;zheyuma97@gmail.com&gt;
Signed-off-by: Sam Ravnborg &lt;sam@ravnborg.org&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1626235762-2590-1-git-send-email-zheyuma97@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>backlight: pwm_bl: Improve bootloader/kernel device handover</title>
<updated>2021-09-15T07:47:41+00:00</updated>
<author>
<name>Daniel Thompson</name>
<email>daniel.thompson@linaro.org</email>
</author>
<published>2021-07-22T14:46:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8810c51077b0c11717c90cd7b4857a64a221579d'/>
<id>8810c51077b0c11717c90cd7b4857a64a221579d</id>
<content type='text'>
commit 79fad92f2e596f5a8dd085788a24f540263ef887 upstream.

Currently there are (at least) two problems in the way pwm_bl starts
managing the enable_gpio pin. Both occur when the backlight is initially
off and the driver finds the pin not already in output mode and, as a
result, unconditionally switches it to output-mode and asserts the signal.

Problem 1: This could cause the backlight to flicker since, at this stage
in driver initialisation, we have no idea what the PWM and regulator are
doing (an unconfigured PWM could easily "rest" at 100% duty cycle).

Problem 2: This will cause us not to correctly honour the
post_pwm_on_delay (which also risks flickers).

Fix this by moving the code to configure the GPIO output mode until after
we have examines the handover state. That allows us to initialize
enable_gpio to off if the backlight is currently off and on if the
backlight is on.

Cc: stable@vger.kernel.org
Reported-by: Marek Vasut &lt;marex@denx.de&gt;
Signed-off-by: Daniel Thompson &lt;daniel.thompson@linaro.org&gt;
Acked-by: Marek Vasut &lt;marex@denx.de&gt;
Tested-by: Marek Vasut &lt;marex@denx.de&gt;
Signed-off-by: Lee Jones &lt;lee.jones@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 79fad92f2e596f5a8dd085788a24f540263ef887 upstream.

Currently there are (at least) two problems in the way pwm_bl starts
managing the enable_gpio pin. Both occur when the backlight is initially
off and the driver finds the pin not already in output mode and, as a
result, unconditionally switches it to output-mode and asserts the signal.

Problem 1: This could cause the backlight to flicker since, at this stage
in driver initialisation, we have no idea what the PWM and regulator are
doing (an unconfigured PWM could easily "rest" at 100% duty cycle).

Problem 2: This will cause us not to correctly honour the
post_pwm_on_delay (which also risks flickers).

Fix this by moving the code to configure the GPIO output mode until after
we have examines the handover state. That allows us to initialize
enable_gpio to off if the backlight is currently off and on if the
backlight is on.

Cc: stable@vger.kernel.org
Reported-by: Marek Vasut &lt;marex@denx.de&gt;
Signed-off-by: Daniel Thompson &lt;daniel.thompson@linaro.org&gt;
Acked-by: Marek Vasut &lt;marex@denx.de&gt;
Tested-by: Marek Vasut &lt;marex@denx.de&gt;
Signed-off-by: Lee Jones &lt;lee.jones@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fbmem: don't allow too huge resolutions</title>
<updated>2021-09-15T07:47:41+00:00</updated>
<author>
<name>Tetsuo Handa</name>
<email>penguin-kernel@i-love.sakura.ne.jp</email>
</author>
<published>2021-09-08T10:27:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5de2ee621bc48fc527f0ed51265eea4bed8b769a'/>
<id>5de2ee621bc48fc527f0ed51265eea4bed8b769a</id>
<content type='text'>
commit 8c28051cdcbe9dfcec6bd0a4709d67a09df6edae upstream.

syzbot is reporting page fault at vga16fb_fillrect() [1], for
vga16fb_check_var() is failing to detect multiplication overflow.

  if (vxres * vyres &gt; maxmem) {
    vyres = maxmem / vxres;
    if (vyres &lt; yres)
      return -ENOMEM;
  }

Since no module would accept too huge resolutions where multiplication
overflow happens, let's reject in the common path.

Link: https://syzkaller.appspot.com/bug?extid=04168c8063cfdde1db5e [1]
Reported-by: syzbot &lt;syzbot+04168c8063cfdde1db5e@syzkaller.appspotmail.com&gt;
Debugged-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Signed-off-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Reviewed-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/185175d6-227a-7b55-433d-b070929b262c@i-love.sakura.ne.jp
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 8c28051cdcbe9dfcec6bd0a4709d67a09df6edae upstream.

syzbot is reporting page fault at vga16fb_fillrect() [1], for
vga16fb_check_var() is failing to detect multiplication overflow.

  if (vxres * vyres &gt; maxmem) {
    vyres = maxmem / vxres;
    if (vyres &lt; yres)
      return -ENOMEM;
  }

Since no module would accept too huge resolutions where multiplication
overflow happens, let's reject in the common path.

Link: https://syzkaller.appspot.com/bug?extid=04168c8063cfdde1db5e [1]
Reported-by: syzbot &lt;syzbot+04168c8063cfdde1db5e@syzkaller.appspotmail.com&gt;
Debugged-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Signed-off-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Reviewed-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/185175d6-227a-7b55-433d-b070929b262c@i-love.sakura.ne.jp
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>backlight: lm3630a: Fix return code of .update_status() callback</title>
<updated>2021-07-20T14:10:45+00:00</updated>
<author>
<name>Uwe Kleine-König</name>
<email>u.kleine-koenig@pengutronix.de</email>
</author>
<published>2021-06-21T12:21:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0f3821c3281b81d98f53b02f3e59328385f87020'/>
<id>0f3821c3281b81d98f53b02f3e59328385f87020</id>
<content type='text'>
[ Upstream commit b9481a667a90ec739995e85f91f3672ca44d6ffa ]

According to &lt;linux/backlight.h&gt; .update_status() is supposed to
return 0 on success and a negative error code otherwise. Adapt
lm3630a_bank_a_update_status() and lm3630a_bank_b_update_status() to
actually do it.

While touching that also add the error code to the failure message.

Signed-off-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Reviewed-by: Daniel Thompson &lt;daniel.thompson@linaro.org&gt;
Signed-off-by: Lee Jones &lt;lee.jones@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit b9481a667a90ec739995e85f91f3672ca44d6ffa ]

According to &lt;linux/backlight.h&gt; .update_status() is supposed to
return 0 on success and a negative error code otherwise. Adapt
lm3630a_bank_a_update_status() and lm3630a_bank_b_update_status() to
actually do it.

While touching that also add the error code to the failure message.

Signed-off-by: Uwe Kleine-König &lt;u.kleine-koenig@pengutronix.de&gt;
Reviewed-by: Daniel Thompson &lt;daniel.thompson@linaro.org&gt;
Signed-off-by: Lee Jones &lt;lee.jones@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
