linux-stable.git/drivers/video/fbdev, branch v6.6.86

fbdev: hyperv_fb: iounmap() the correct memory when removing a device

2025-03-22T19:50:37+00:00

[ Upstream commit 7241c886a71797cc51efc6fadec7076fcf6435c2 ]

When a Hyper-V framebuffer device is removed, or the driver is unbound
from a device, any allocated and/or mapped memory must be released. In
particular, MMIO address space that was mapped to the framebuffer must
be unmapped. Current code unmaps the wrong address, resulting in an
error like:

[ 4093.980597] iounmap: bad address 00000000c936c05c

followed by a stack dump.

Commit d21987d709e8 ("video: hyperv: hyperv_fb: Support deferred IO for
Hyper-V frame buffer driver") changed the kind of address stored in
info->screen_base, and the iounmap() call in hvfb_putmem() was not
updated accordingly.

Fix this by updating hvfb_putmem() to unmap the correct address.

Fixes: d21987d709e8 ("video: hyperv: hyperv_fb: Support deferred IO for Hyper-V frame buffer driver")
Signed-off-by: Michael Kelley 
Reviewed-by: Saurabh Sengar 
Link: https://lore.kernel.org/r/20250209235252.2987-1-mhklinux@outlook.com
Signed-off-by: Wei Liu 
Message-ID: <20250209235252.2987-1-mhklinux@outlook.com>
Signed-off-by: Sasha Levin

fbdev: omap: use threaded IRQ for LCD DMA

2025-02-21T12:57:09+00:00

[ Upstream commit e4b6b665df815b4841e71b72f06446884e8aad40 ]

When using touchscreen and framebuffer, Nokia 770 crashes easily with:

    BUG: scheduling while atomic: irq/144-ads7846/82/0x00010000
    Modules linked in: usb_f_ecm g_ether usb_f_rndis u_ether libcomposite configfs omap_udc ohci_omap ohci_hcd
    CPU: 0 UID: 0 PID: 82 Comm: irq/144-ads7846 Not tainted 6.12.7-770 #2
    Hardware name: Nokia 770
    Call trace:
     unwind_backtrace from show_stack+0x10/0x14
     show_stack from dump_stack_lvl+0x54/0x5c
     dump_stack_lvl from __schedule_bug+0x50/0x70
     __schedule_bug from __schedule+0x4d4/0x5bc
     __schedule from schedule+0x34/0xa0
     schedule from schedule_preempt_disabled+0xc/0x10
     schedule_preempt_disabled from __mutex_lock.constprop.0+0x218/0x3b4
     __mutex_lock.constprop.0 from clk_prepare_lock+0x38/0xe4
     clk_prepare_lock from clk_set_rate+0x18/0x154
     clk_set_rate from sossi_read_data+0x4c/0x168
     sossi_read_data from hwa742_read_reg+0x5c/0x8c
     hwa742_read_reg from send_frame_handler+0xfc/0x300
     send_frame_handler from process_pending_requests+0x74/0xd0
     process_pending_requests from lcd_dma_irq_handler+0x50/0x74
     lcd_dma_irq_handler from __handle_irq_event_percpu+0x44/0x130
     __handle_irq_event_percpu from handle_irq_event+0x28/0x68
     handle_irq_event from handle_level_irq+0x9c/0x170
     handle_level_irq from generic_handle_domain_irq+0x2c/0x3c
     generic_handle_domain_irq from omap1_handle_irq+0x40/0x8c
     omap1_handle_irq from generic_handle_arch_irq+0x28/0x3c
     generic_handle_arch_irq from call_with_stack+0x1c/0x24
     call_with_stack from __irq_svc+0x94/0xa8
    Exception stack(0xc5255da0 to 0xc5255de8)
    5da0: 00000001 c22fc620 00000000 00000000 c08384a8 c106fc00 00000000 c240c248
    5dc0: c113a600 c3f6ec30 00000001 00000000 c22fc620 c5255df0 c22fc620 c0279a94
    5de0: 60000013 ffffffff
     __irq_svc from clk_prepare_lock+0x4c/0xe4
     clk_prepare_lock from clk_get_rate+0x10/0x74
     clk_get_rate from uwire_setup_transfer+0x40/0x180
     uwire_setup_transfer from spi_bitbang_transfer_one+0x2c/0x9c
     spi_bitbang_transfer_one from spi_transfer_one_message+0x2d0/0x664
     spi_transfer_one_message from __spi_pump_transfer_message+0x29c/0x498
     __spi_pump_transfer_message from __spi_sync+0x1f8/0x2e8
     __spi_sync from spi_sync+0x24/0x40
     spi_sync from ads7846_halfd_read_state+0x5c/0x1c0
     ads7846_halfd_read_state from ads7846_irq+0x58/0x348
     ads7846_irq from irq_thread_fn+0x1c/0x78
     irq_thread_fn from irq_thread+0x120/0x228
     irq_thread from kthread+0xc8/0xe8
     kthread from ret_from_fork+0x14/0x28

As a quick fix, switch to a threaded IRQ which provides a stable system.

Signed-off-by: Aaro Koskinen 
Reviewed-by: Linus Walleij 
Signed-off-by: Helge Deller 
Signed-off-by: Sasha Levin

fbdev: omapfb: Fix an OF node leak in dss_of_port_get_parent_device()

2025-02-08T08:52:21+00:00

[ Upstream commit de124b61e179e690277116e6be512e4f422b5dd8 ]

dss_of_port_get_parent_device() leaks an OF node reference when i >= 2
and struct device_node *np is present. Since of_get_next_parent()
obtains a reference of the returned OF node, call of_node_put() before
returning NULL.

This was found by an experimental verifier that I am developing, and no
runtime test was able to be performed due to that lack of actual
devices.

Fixes: f76ee892a99e ("omapfb: copy omapdss & displays for omapfb")
Signed-off-by: Joe Hattori 
Reviewed-by: Laurent Pinchart 
Signed-off-by: Helge Deller 
Signed-off-by: Sasha Levin

fbdev: sh7760fb: Fix a possible memory leak in sh7760fb_alloc_mem()

2024-12-09T09:32:21+00:00

[ Upstream commit f89d17ae2ac42931be2a0153fecbf8533280c927 ]

When information such as info->screen_base is not ready, calling
sh7760fb_free_mem() does not release memory correctly. Call
dma_free_coherent() instead.

Fixes: 4a25e41831ee ("video: sh7760fb: SH7760/SH7763 LCDC framebuffer driver")
Signed-off-by: Zhen Lei 
Reviewed-by: Dmitry Baryshkov 
Signed-off-by: Helge Deller 
Signed-off-by: Sasha Levin

fbdev: sisfb: Fix strbuf array overflow

2024-10-17T13:24:22+00:00

[ Upstream commit 9cf14f5a2746c19455ce9cb44341b5527b5e19c3 ]

The values of the variables xres and yres are placed in strbuf.
These variables are obtained from strbuf1.
The strbuf1 array contains digit characters
and a space if the array contains non-digit characters.
Then, when executing sprintf(strbuf, "%ux%ux8", xres, yres);
more than 16 bytes will be written to strbuf.
It is suggested to increase the size of the strbuf array to 24.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

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

fbcon: Fix a NULL pointer dereference issue in fbcon_putcs

2024-10-17T13:24:21+00:00

[ Upstream commit 5b97eebcce1b4f3f07a71f635d6aa3af96c236e7 ]

syzbot has found a NULL pointer dereference bug in fbcon.
Here is the simplified C reproducer:

struct param {
	uint8_t type;
	struct tiocl_selection ts;
};

int main()
{
	struct fb_con2fbmap con2fb;
	struct param param;

	int fd = open("/dev/fb1", 0, 0);

	con2fb.console = 0x19;
	con2fb.framebuffer = 0;
	ioctl(fd, FBIOPUT_CON2FBMAP, &con2fb);

	param.type = 2;
	param.ts.xs = 0; param.ts.ys = 0;
	param.ts.xe = 0; param.ts.ye = 0;
	param.ts.sel_mode = 0;

	int fd1 = open("/dev/tty1", O_RDWR, 0);
	ioctl(fd1, TIOCLINUX, ¶m);

	con2fb.console = 1;
	con2fb.framebuffer = 0;
	ioctl(fd, FBIOPUT_CON2FBMAP, &con2fb);

	return 0;
}

After calling ioctl(fd1, TIOCLINUX, ¶m), the subsequent ioctl(fd, FBIOPUT_CON2FBMAP, &con2fb)
causes the kernel to follow a different execution path:

 set_con2fb_map
  -> con2fb_init_display
   -> fbcon_set_disp
    -> redraw_screen
     -> hide_cursor
      -> clear_selection
       -> highlight
        -> invert_screen
         -> do_update_region
          -> fbcon_putcs
           -> ops->putcs

Since ops->putcs is a NULL pointer, this leads to a kernel panic.
To prevent this, we need to call set_blitting_type() within set_con2fb_map()
to properly initialize ops->putcs.

Reported-by: syzbot+3d613ae53c031502687a@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=3d613ae53c031502687a
Tested-by: syzbot+3d613ae53c031502687a@syzkaller.appspotmail.com
Signed-off-by: Qianqiang Liu 
Signed-off-by: Helge Deller 
Signed-off-by: Sasha Levin

fbdev: pxafb: Fix possible use after free in pxafb_task()

2024-10-10T09:57:31+00:00

[ Upstream commit 4a6921095eb04a900e0000da83d9475eb958e61e ]

In the pxafb_probe function, it calls the pxafb_init_fbinfo function,
after which &fbi->task is associated with pxafb_task. Moreover,
within this pxafb_init_fbinfo function, the pxafb_blank function
within the &pxafb_ops struct is capable of scheduling work.

If we remove the module which will call pxafb_remove to make cleanup,
it will call unregister_framebuffer function which can call
do_unregister_framebuffer to free fbi->fb through
put_fb_info(fb_info), while the work mentioned above will be used.
The sequence of operations that may lead to a UAF bug is as follows:

CPU0                                                CPU1

                                   | pxafb_task
pxafb_remove                       |
unregister_framebuffer(info)       |
do_unregister_framebuffer(fb_info) |
put_fb_info(fb_info)               |
// free fbi->fb                    | set_ctrlr_state(fbi, state)
                                   | __pxafb_lcd_power(fbi, 0)
                                   | fbi->lcd_power(on, &fbi->fb.var)
                                   | //use fbi->fb

Fix it by ensuring that the work is canceled before proceeding
with the cleanup in pxafb_remove.

Note that only root user can remove the driver at runtime.

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

fbdev: efifb: Register sysfs groups through driver core

2024-10-10T09:57:31+00:00

[ Upstream commit 95cdd538e0e5677efbdf8aade04ec098ab98f457 ]

The driver core can register and cleanup sysfs groups already.
Make use of that functionality to simplify the error handling and
cleanup.

Also avoid a UAF race during unregistering where the sysctl attributes
were usable after the info struct was freed.

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

fbdev: hpfb: Fix an error handling path in hpfb_dio_probe()

2024-10-04T14:29:06+00:00

[ Upstream commit aa578e897520f32ae12bec487f2474357d01ca9c ]

If an error occurs after request_mem_region(), a corresponding
release_mem_region() should be called, as already done in the remove
function.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Christophe JAILLET 
Signed-off-by: Helge Deller 
Signed-off-by: Sasha Levin

fbdev: vesafb: Detect VGA compatibility from screen info's VESA attributes

2024-08-11T10:47:16+00:00

[ Upstream commit c2bc958b2b03e361f14df99983bc64a39a7323a3 ]

Test the vesa_attributes field in struct screen_info for compatibility
with VGA hardware. Vesafb currently tests bit 1 in screen_info's
capabilities field which indicates a 64-bit lfb address and is
unrelated to VGA compatibility.

Section 4.4 of the Vesa VBE 2.0 specifications defines that bit 5 in
the mode's attributes field signals VGA compatibility. The mode is
compatible with VGA hardware if the bit is clear. In that case, the
driver can access VGA state of the VBE's underlying hardware. The
vesafb driver uses this feature to program the color LUT in palette
modes. Without, colors might be incorrect.

The problem got introduced in commit 89ec4c238e7a ("[PATCH] vesafb: Fix
incorrect logo colors in x86_64"). It incorrectly stores the mode
attributes in the screen_info's capabilities field and updates vesafb
accordingly. Later, commit 5e8ddcbe8692 ("Video mode probing support for
the new x86 setup code") fixed the screen_info, but did not update vesafb.
Color output still tends to work, because bit 1 in capabilities is
usually 0.

Besides fixing the bug in vesafb, this commit introduces a helper that
reads the correct bit from screen_info.

Signed-off-by: Thomas Zimmermann 
Fixes: 5e8ddcbe8692 ("Video mode probing support for the new x86 setup code")
Reviewed-by: Javier Martinez Canillas 
Cc:  # v2.6.23+
Signed-off-by: Helge Deller 
Signed-off-by: Sasha Levin