dlfb_ops_mmap() uses remap_pfn_range() to map vmalloc framebuffer pages
to userspace but sets no vm_ops on the VMA. This means the kernel cannot
track active mmaps. When dlfb_realloc_framebuffer() replaces the backing
buffer via FBIOPUT_VSCREENINFO, existing mmap PTEs are not invalidated.
On USB disconnect, dlfb_ops_destroy() calls vfree() on the old pages
while userspace PTEs still reference them, resulting in a use-after-free:
the process retains read/write access to freed kernel pages.
Add vm_operations_struct with open/close callbacks that maintain an
atomic mmap_count on struct dlfb_data. In dlfb_realloc_framebuffer(),
check mmap_count and return -EBUSY if the buffer is currently mapped,
preventing buffer replacement while userspace holds stale PTEs.
Tested with PoC using dummy_hcd + raw_gadget USB device emulation.
Signed-off-by: Rajat Gupta <rajgupt@qti.qualcomm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Remove duplicate inclusion of linux/module.h in fb_defio.c to clean up
redundant code.
Signed-off-by: Chen Ni <nichen@iscas.ac.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
The driver calls ioremap() on the HGA video memory at 0xb0000 without
first reserving the physical address range. This leaves the kernel
resource tree incomplete and can cause silent conflicts with other
drivers claiming the same range.
Add a devm_request_mem_region() call before ioremap() in
hga_card_detect() to reserve the memory region.
Signed-off-by: Hardik Phalet <hardik.phalet@pm.me>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Use devm_platform_get_and_ioremap_resource() for resource 0 (the MMIO
control register range) instead of open-coding platform_get_resource()
and devm_ioremap() separately. The helper requests the memory region
before mapping it, which registers the range in /proc/iomem and prevents
another driver from mapping the same registers.
This makes resource 0 consistent with resource 1 (the framebuffer),
which already uses devm_platform_get_and_ioremap_resource().
Assisted-by: Claude:claude-sonnet-4-6
Signed-off-by: Amit Barzilai <amit.barzilai22@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Use devm_platform_get_and_ioremap_resource() instead of open-coding
platform_get_resource() and devm_ioremap() separately. The helper
requests the memory region before mapping it, which registers the range
in /proc/iomem and prevents another driver from mapping the same
registers.
Assisted-by: Claude:claude-sonnet-4-6
Signed-off-by: Amit Barzilai <amit.barzilai22@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
When CONFIG_FB_SAVAGE_I2C is enabled, savagefb_probe() can build both an
EDID-derived monspecs.modedb and a modelist from it before later failing.
The normal success path frees monspecs.modedb after the initial mode selection,
but the probe error path only deletes the I2C busses and misses the
EDID-derived allocations.
Free both the modelist and monspecs.modedb on the failed: unwind path.
Co-developed-by: Myeonghun Pak <mhun512@gmail.com>
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
Co-developed-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Ijae Kim <ae878000@gmail.com>
Co-developed-by: Taegyu Kim <tmk5904@psu.edu>
Signed-off-by: Taegyu Kim <tmk5904@psu.edu>
Signed-off-by: Yuho Choi <dbgh9129@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
offb_init_nodriver() gets a referenced PCI device with pci_get_device().
If pci_enable_device() fails, the function returns without dropping that
reference.
Release the PCI device reference before returning from the
pci_enable_device() failure path.
Fixes: 5bda8f7b54 ("video: fbdev: offb: Call pci_enable_device() before using the PCI VGA device")
Co-developed-by: Myeonghun Pak <mhun512@gmail.com>
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
Co-developed-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Ijae Kim <ae878000@gmail.com>
Co-developed-by: Taegyu Kim <tmk5904@psu.edu>
Signed-off-by: Taegyu Kim <tmk5904@psu.edu>
Signed-off-by: Yuho Choi <dbgh9129@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Much like commit 19f953e743 ("fbdev: fb_pm2fb: Avoid potential divide
by zero error"), we also need to prevent that same crash from happening
in the udlfb driver as it uses pixclock directly when dividing, which
will crash.
Cc: Bernie Thompson <bernie@plugable.com>
Cc: Helge Deller <deller@gmx.de>
Fixes: 59277b679f ("Staging: udlfb: add dynamic modeset support")
Assisted-by: gregkh_clanker_t1000
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Much like commit 19f953e743 ("fbdev: fb_pm2fb: Avoid potential divide
by zero error"), we also need to prevent that same crash from happening
in the udlfb driver as it uses pixclock directly when dividing, which
will crash.
Cc: Helge Deller <deller@gmx.de>
Assisted-by: gregkh_clanker_t1000
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Fix the warning about inconsistent returns for '&rg->lock' in
omapfb_mmap() function. The warning arises because the error path
uses 'ofbi->region' while the normal path uses 'rg'.
smatch warnings:
drivers/video/fbdev/omap2/omapfb/omapfb-main.c:1126 omapfb_mmap()
warn: inconsistent returns '&rg->lock'.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Hongling Zeng <zenghongling@kylinos.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
Move all temporary state of the font-rotation code into the struct
rotated in struct fbcon_par. Protect it with the Kconfig symbol
CONFIG_FRAMEBUFFER_CONSOLE_ROTATION. Avoids mixing it up with fbcon's
regular state.
v2:
- fix typos
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Fbcon creates a cursor shape on the fly from the user-configured
settings. The logic to create a glyph with the cursor's bitmap mask
is duplicated in four places. In the cases that involve console
rotation, the implementation further rotates the cursor glyph for
displaying.
Consolidate all cursor-mask creation in a single helper. Update the
callers accordingly. For console rotation, use the glyph helpers to
rotate the created cursor glyph to the correct orientation.
v2:
- fix sparse truncated-bits warning
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Move the core of fbcon's font-rotation code to the font library as
the new helper font_data_rotate(). The code can rotate in steps of
90°. For completeness, it also copies the glyph data for multiples
of 360°.
Bring back the memset optimization. A memset to 0 again clears the
whole glyph output buffer. Then use the internal rotation helpers on
the cleared output. Fbcon's original implementation worked like this,
but lost it during refactoring.
Replace fbcon's font-rotation code with the new implementations.
All that's left to do for fbcon is to maintain its internal fbcon
state.
v2:
- fix typos
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Move the glyph rotation helpers from fbcon to the font library. Wrap them
behind clean interfaces. Also clear the output memory to zero. Previously,
the implementation relied on the caller to do that.
Go through the fbcon code and callers of the glyph-rotation helpers. In
addition to the font rotation, there's also the cursor code, which uses
the rotation helpers.
The font-rotation relied on a single memset to zero for the whole font.
This is now multiple memsets on each glyph. This will be sorted out when
the font library also implements font rotation.
Building glyph rotation in the font library still depends on
CONFIG_FRAMEBUFFER_CONSOLE_ROTATION=y. If we get more users of the code,
we can still add a dedicated Kconfig symbol to the font library.
No changes have been made to the actual implementation of the rotate_*()
and pattern_*() functions. These will be refactored as separate changes.
v2:
- fix typos
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Implement pitch and size calculation for a single font glyph in the
new helpers font_glyph_pitch() and font_glyph_size(). Replace the
instances where the calculations are open-coded.
Note that in the case of fbcon console rotation, the parameters for
a glyph's width and height might be reversed. This is intentional.
v2:
- fix typos in commit message
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Clear the font buffer if the reallocation during console rotation fails
in fbcon_rotate_font(). The putcs implementations for the rotated buffer
will return early in this case. See [1] for an example.
Currently, fbcon_rotate_font() keeps the old buffer, which is too small
for the rotated font. Printing to the rotated console with a high-enough
character code will overflow the font buffer.
v2:
- fix typos in commit message
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 6cc50e1c5b ("[PATCH] fbcon: Console Rotation - Add support to rotate font bitmap")
Cc: stable@vger.kernel.org # v2.6.15+
Link: https://elixir.bootlin.com/linux/v6.19/source/drivers/video/fbdev/core/fbcon_ccw.c#L144 # [1]
Signed-off-by: Helge Deller <deller@gmx.de>
With clang and W=1:
drivers/video/fbdev/aty/atyfb_base.c:2327:24: warning: variable 'fb_list' set but not used [-Wunused-but-set-global]
2327 | static struct fb_info *fb_list = NULL;
Indeed, the last user of fb_list was removed in 2004, while the actual
linked list was removed in 2002.
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202603300931.osMYxYZ7-lkp@intel.com/
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Clang is not happy about set but unused variable:
drivers/video/fbdev/matrox/g450_pll.c:412:18: error: variable 'mnp' set but not used
412 | unsigned int mnp;
| ^
1 error generated.
Since the commit 7b987887f9 ("video: fbdev: matroxfb: remove dead code
and set but not used variable") the 'mnp' became unused, but eliminating
that code might have side-effects. The question here is what should we do
with 'mnp'? The easiest way out is just mark it with __maybe_unused which
will shut the compiler up and won't change any possible IO flow. So does
this change.
A dive into the history of the driver:
The problem was revealed when the #if 0 guarded code along with unused
pixel_vco variable was removed. That code was introduced in the original
commit 213d22146d1f ("[PATCH] (1/3) matroxfb for 2.5.3"). And then guarded
in the commit 705e41f82988 ("matroxfb DVI updates: Handle DVI output on
G450/G550. Powerdown unused portions of G450/G550 DAC. Split G450/G550 DAC
from older DAC1064 handling. Modify PLL setting when both CRTCs use same
pixel clocks.").
NOTE: The two commits mentioned above pre-date Git era and available in
history.git repository for archaeological purposes.
Even without that guard the modern compilers may see that the pixel_vco
wasn't ever used and seems a leftover after some debug or review made
25 years ago.
The g450_mnp2vco() doesn't have any IO and as Jason said doesn't seem
to have any side effects either than some unneeded CPU processing during
runtime. I agree that's unlikely that timeout (or heating up the CPU) has
any effect on the HW (GPU/display) functionality.
Fixes: 7b987887f9 ("video: fbdev: matroxfb: remove dead code and set but not used variable")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Helge Deller <deller@gmx.de>
The help text for CONFIG_FB_NVIDIA refers to obsolete hardware and
incorrect default behaviour. This patch updates the description to
reflect the current state of the driver and supported devices.
Signed-off-by: robgithub <rob.github@jumpstation.co.uk>
Signed-off-by: Helge Deller <deller@gmx.de>
The hwa742_init() function did not check the return value of clk_get().
This could lead to dereferencing an error pointer in subsequent clock
operations, potentially causing a kernel crash.
Fix this by adding a missing error check and ensuring proper clock
resource cleanup on failure and driver removal.
Signed-off-by: Chen Ni <nichen@iscas.ac.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
The function viafb_lcd_get_mobile_state() calls ioremap() without
checking the return value. If ioremap() fails (returns NULL), the
subsequent readw() will cause a NULL pointer dereference.
Signed-off-by: Wang Jun <1742789905@qq.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Add font_data_export() and update consoles to use it.
The helper font_data_export() is based on code in fbcon_get_font().
It extends the size of a single glyph to match the requested vpitch,
which us usually 32 bytes for fonts from user space. Internal fonts
have a pitch according to the glyph's height.
The implementation of font_data_export() differs in several ways from
the original code. The original implementation distinguished between
different pitches of the font data. This is not necessary as the pitch
is a parameter in the copying.
There was also special handling for a font pitch of 3 bytes, which got
expanded to 4 bytes (with trailing bits on each scanline). The logic
originated from long before git history exists even in the historical
tree. So it is not clear why this was implemented. It is not what user
space expects. The setfont utitlity loads font with 3-bytes pitches and
expects to read such fonts with a 3-byte pitch. For any font width, the
font pitch is always the width extended to the next multiple of 8. See
[1] for the user-space font-reading code.
With the changes to handling the font pitches, font_data_export() replaces
the original code's various special cases with a single copying logic.
v3:
- fix typos (Helge)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://github.com/legionus/kbd/blob/v2.9.0/src/libkfont/kdfontop.c#L73 # [1]
Signed-off-by: Helge Deller <deller@gmx.de>
Add font_data_import() and update consoles to use it.
The implementation of font_data_import() is based on code from fbcon,
which supports overflow checks and crc32 checksums. Fbcon uses the crc32
checksum.
Newport_con now implements the same overflow checks as fbcon. As before,
this console does not support checksums, which are optional. Newport_con
can now also handle input font data with a vertical pitch other than 32
bytes. (The vertical pitch is the offset between two glyphs in the font
data.)
As an internal change, remove the const qualifier from the data field
if struct font_data. This allows font_data_import() to write the data
without type casting. For all users of the font data via font_data_t,
the stored data is still read only.
v3:
- fix typos
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Add font_data_is_equal() and update consoles to use it.
Font data is equal if it has the same size and contains the same values
on all bytes. Only fbcon uses a crc32 checksum. If set in both operands
the checksums have to be equal.
The new helper also guarantees to not compare internal fonts against
fonts from user space. Internal fonts cannot be ref-counted, so making
them equal to user-space fonts with the same byte sequence results in
undefined behavior.
The test only compares data buffers. Their interpretation is up each
console. Therefore remove a width test in fbcon_set_font().
v3:
- rebase onto font_data_{get,put}()
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Rajat Gupta
Chen Ni
Hardik Phalet
Amit Barzilai
Ethan Carter Edwards
Yuho Choi
Greg Kroah-Hartman
Hongling Zeng
Thomas Zimmermann
Geert Uytterhoeven
Andy Shevchenko
robgithub
Wang Jun