linux-stable.git/drivers/video/fbdev/core, branch v5.4.261

fbdev: fix potential OOB read in fast_imageblit()

2023-08-30T14:27:21+00:00

[ Upstream commit c2d22806aecb24e2de55c30a06e5d6eb297d161d ]

There is a potential OOB read at fast_imageblit, for
"colortab[(*src >> 4)]" can become a negative value due to
"const char *s = image->data, *src".
This change makes sure the index for colortab always positive
or zero.

Similar commit:
https://patchwork.kernel.org/patch/11746067

Potential bug report:
https://groups.google.com/g/syzkaller-bugs/c/9ubBXKeKXf4/m/k-QXy4UgAAAJ

Signed-off-by: Zhang Shurong 
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller 
Signed-off-by: Sasha Levin

fbdev: Fix sys_imageblit() for arbitrary image widths

2023-08-30T14:27:21+00:00

[ Upstream commit 61bfcb6a3b981e8f19e044ac8c3de6edbe6caf70 ]

Commit 6f29e04938bf ("fbdev: Improve performance of sys_imageblit()")
broke sys_imageblit() for image width that are not aligned to 8-bit
boundaries. Fix this by handling the trailing pixels on each line
separately. The performance improvements in the original commit do not
regress by this change.

Signed-off-by: Thomas Zimmermann 
Fixes: 6f29e04938bf ("fbdev: Improve performance of sys_imageblit()")
Reviewed-by: Javier Martinez Canillas 
Acked-by: Daniel Vetter 
Tested-by: Geert Uytterhoeven 
Cc: Thomas Zimmermann 
Cc: Javier Martinez Canillas 
Cc: Sam Ravnborg 
Link: https://patchwork.freedesktop.org/patch/msgid/20220313192952.12058-2-tzimmermann@suse.de
Stable-dep-of: c2d22806aecb ("fbdev: fix potential OOB read in fast_imageblit()")
Signed-off-by: Sasha Levin

fbdev: Improve performance of sys_imageblit()

2023-08-30T14:27:21+00:00

[ Upstream commit 6f29e04938bf509fccfad490a74284cf158891ce ]

Improve the performance of sys_imageblit() by manually unrolling
the inner blitting loop and moving some invariants out. The compiler
failed to do this automatically. The resulting binary code was even
slower than the cfb_imageblit() helper, which uses the same algorithm,
but operates on I/O memory.

A microbenchmark measures the average number of CPU cycles
for sys_imageblit() after a stabilizing period of a few minutes
(i7-4790, FullHD, simpledrm, kernel with debugging). The value
for CFB is given as a reference.

  sys_imageblit(), new: 25934 cycles
  sys_imageblit(), old: 35944 cycles
  cfb_imageblit():      30566 cycles

In the optimized case, sys_imageblit() is now ~30% faster than before
and ~20% faster than cfb_imageblit().

v2:
	* move switch out of inner loop (Gerd)
	* remove test for alignment of dst1 (Sam)

Signed-off-by: Thomas Zimmermann 
Reviewed-by: Javier Martinez Canillas 
Acked-by: Sam Ravnborg 
Link: https://patchwork.freedesktop.org/patch/msgid/20220223193804.18636-3-tzimmermann@suse.de
Stable-dep-of: c2d22806aecb ("fbdev: fix potential OOB read in fast_imageblit()")
Signed-off-by: Sasha Levin

fbcon: Fix null-ptr-deref in soft_cursor

2023-06-09T08:29:03+00:00

commit d78bd6cc68276bd57f766f7cb98bfe32c23ab327 upstream.

syzbot repored this bug in the softcursor code:

BUG: KASAN: null-ptr-deref in soft_cursor+0x384/0x6b4 drivers/video/fbdev/core/softcursor.c:70
Read of size 16 at addr 0000000000000200 by task kworker/u4:1/12

CPU: 0 PID: 12 Comm: kworker/u4:1 Not tainted 6.4.0-rc3-syzkaller-geb0f1697d729 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
Workqueue: events_power_efficient fb_flashcursor
Call trace:
 dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233
 show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106
 print_report+0xe4/0x514 mm/kasan/report.c:465
 kasan_report+0xd4/0x130 mm/kasan/report.c:572
 kasan_check_range+0x264/0x2a4 mm/kasan/generic.c:187
 __asan_memcpy+0x3c/0x84 mm/kasan/shadow.c:105
 soft_cursor+0x384/0x6b4 drivers/video/fbdev/core/softcursor.c:70
 bit_cursor+0x113c/0x1a64 drivers/video/fbdev/core/bitblit.c:377
 fb_flashcursor+0x35c/0x54c drivers/video/fbdev/core/fbcon.c:380
 process_one_work+0x788/0x12d4 kernel/workqueue.c:2405
 worker_thread+0x8e0/0xfe8 kernel/workqueue.c:2552
 kthread+0x288/0x310 kernel/kthread.c:379
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:853

This fix let bit_cursor() bail out early when a font bitmap
isn't available yet.

Signed-off-by: Helge Deller 
Reported-by: syzbot+d910bd780e6efac35869@syzkaller.appspotmail.com
Acked-by: Sam Ravnborg 
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman

fbdev: modedb: Add 1920x1080 at 60 Hz video mode

2023-06-09T08:28:55+00:00

[ Upstream commit c8902258b2b8ecaa1b8d88c312853c5b14c2553d ]

Add typical resolution for Full-HD monitors.

Signed-off-by: Helge Deller 
Signed-off-by: Sasha Levin

fbcon: Check font dimension limits

2023-02-22T11:50:27+00:00

commit 2b09d5d364986f724f17001ccfe4126b9b43a0be upstream.

blit_x and blit_y are u32, so fbcon currently cannot support fonts
larger than 32x32.

The 32x32 case also needs shifting an unsigned int, to properly set bit
31, otherwise we get "UBSAN: shift-out-of-bounds in fbcon_set_font",
as reported on:

http://lore.kernel.org/all/IA1PR07MB98308653E259A6F2CE94A4AFABCE9@IA1PR07MB9830.namprd07.prod.outlook.com
Kernel Branch: 6.2.0-rc5-next-20230124
Kernel config: https://drive.google.com/file/d/1F-LszDAizEEH0ZX0HcSR06v5q8FPl2Uv/view?usp=sharing
Reproducer: https://drive.google.com/file/d/1mP1jcLBY7vWCNM60OMf-ogw-urQRjNrm/view?usp=sharing

Reported-by: Sanan Hasanov 
Signed-off-by: Samuel Thibault 
Fixes: 2d2699d98492 ("fbcon: font setting should check limitation of driver")
Cc: stable@vger.kernel.org
Tested-by: Miko Larsson 
Reviewed-by: Greg Kroah-Hartman 
Signed-off-by: Helge Deller 
Signed-off-by: Greg Kroah-Hartman

fbcon: Use kzalloc() in fbcon_prepare_logo()

2022-12-14T10:30:41+00:00

[ Upstream commit a6a00d7e8ffd78d1cdb7a43f1278f081038c638f ]

A kernel built with syzbot's config file reported that

  scr_memcpyw(q, save, array3_size(logo_lines, new_cols, 2))

causes uninitialized "save" to be copied.

  ----------
  [drm] Initialized vgem 1.0.0 20120112 for vgem on minor 0
  [drm] Initialized vkms 1.0.0 20180514 for vkms on minor 1
  Console: switching to colour frame buffer device 128x48
  =====================================================
  BUG: KMSAN: uninit-value in do_update_region+0x4b8/0xba0
   do_update_region+0x4b8/0xba0
   update_region+0x40d/0x840
   fbcon_switch+0x3364/0x35e0
   redraw_screen+0xae3/0x18a0
   do_bind_con_driver+0x1cb3/0x1df0
   do_take_over_console+0x11cb/0x13f0
   fbcon_fb_registered+0xacc/0xfd0
   register_framebuffer+0x1179/0x1320
   __drm_fb_helper_initial_config_and_unlock+0x23ad/0x2b40
   drm_fbdev_client_hotplug+0xbea/0xda0
   drm_fbdev_generic_setup+0x65e/0x9d0
   vkms_init+0x9f3/0xc76
   (...snipped...)

  Uninit was stored to memory at:
   fbcon_prepare_logo+0x143b/0x1940
   fbcon_init+0x2c1b/0x31c0
   visual_init+0x3e7/0x820
   do_bind_con_driver+0x14a4/0x1df0
   do_take_over_console+0x11cb/0x13f0
   fbcon_fb_registered+0xacc/0xfd0
   register_framebuffer+0x1179/0x1320
   __drm_fb_helper_initial_config_and_unlock+0x23ad/0x2b40
   drm_fbdev_client_hotplug+0xbea/0xda0
   drm_fbdev_generic_setup+0x65e/0x9d0
   vkms_init+0x9f3/0xc76
   (...snipped...)

  Uninit was created at:
   __kmem_cache_alloc_node+0xb69/0x1020
   __kmalloc+0x379/0x680
   fbcon_prepare_logo+0x704/0x1940
   fbcon_init+0x2c1b/0x31c0
   visual_init+0x3e7/0x820
   do_bind_con_driver+0x14a4/0x1df0
   do_take_over_console+0x11cb/0x13f0
   fbcon_fb_registered+0xacc/0xfd0
   register_framebuffer+0x1179/0x1320
   __drm_fb_helper_initial_config_and_unlock+0x23ad/0x2b40
   drm_fbdev_client_hotplug+0xbea/0xda0
   drm_fbdev_generic_setup+0x65e/0x9d0
   vkms_init+0x9f3/0xc76
   (...snipped...)

  CPU: 2 PID: 1 Comm: swapper/0 Not tainted 6.1.0-rc4-00356-g8f2975c2bb4c #924
  Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
  ----------

Signed-off-by: Tetsuo Handa 
Signed-off-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/cad03d25-0ea0-32c4-8173-fd1895314bce@I-love.SAKURA.ne.jp
Signed-off-by: Sasha Levin

fbcon: Fix boundary checks for fbcon=vc:n1-n2 parameters

2022-08-25T09:17:22+00:00

commit cad564ca557f8d3bb3b1fa965d9a2b3f6490ec69 upstream.

The user may use the fbcon=vc:- option to tell fbcon to take
over the given range (n1...n2) of consoles. The value for n1 and n2
needs to be a positive number and up to (MAX_NR_CONSOLES - 1).
The given values were not fully checked against those boundaries yet.

To fix the issue, convert first_fb_vc and last_fb_vc to unsigned
integers and check them against the upper boundary, and make sure that
first_fb_vc is smaller than last_fb_vc.

Cc: stable@vger.kernel.org # v4.19+
Reviewed-by: Daniel Vetter 
Signed-off-by: Helge Deller 
Link: https://patchwork.freedesktop.org/patch/msgid/YpkYRMojilrtZIgM@p100
Signed-off-by: Greg Kroah-Hartman

fbcon: Prevent that screen size is smaller than font size

2022-07-12T14:30:47+00:00

commit e64242caef18b4a5840b0e7a9bff37abd4f4f933 upstream.

We need to prevent that users configure a screen size which is smaller than the
currently selected font size. Otherwise rendering chars on the screen will
access memory outside the graphics memory region.

This patch adds a new function fbcon_modechange_possible() which
implements this check and which later may be extended with other checks
if necessary.  The new function is called from the FBIOPUT_VSCREENINFO
ioctl handler in fbmem.c, which will return -EINVAL if userspace asked
for a too small screen size.

Signed-off-by: Helge Deller 
Reviewed-by: Geert Uytterhoeven 
Cc: stable@vger.kernel.org # v5.4+
Signed-off-by: Greg Kroah-Hartman

fbcon: Disallow setting font bigger than screen size

2022-07-12T14:30:47+00:00

commit 65a01e601dbba8b7a51a2677811f70f783766682 upstream.

Prevent that users set a font size which is bigger than the physical screen.
It's unlikely this may happen (because screens are usually much larger than the
fonts and each font char is limited to 32x32 pixels), but it may happen on
smaller screens/LCD displays.

Signed-off-by: Helge Deller 
Reviewed-by: Daniel Vetter 
Reviewed-by: Geert Uytterhoeven 
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Greg Kroah-Hartman