[ Upstream commit a1f3058930 ]
Recently, we discovered the following issue through syzkaller:
BUG: KASAN: slab-use-after-free in fb_mode_is_equal+0x285/0x2f0
Read of size 4 at addr ff11000001b3c69c by task syz.xxx
...
Call Trace:
<TASK>
dump_stack_lvl+0xab/0xe0
print_address_description.constprop.0+0x2c/0x390
print_report+0xb9/0x280
kasan_report+0xb8/0xf0
fb_mode_is_equal+0x285/0x2f0
fbcon_mode_deleted+0x129/0x180
fb_set_var+0xe7f/0x11d0
do_fb_ioctl+0x6a0/0x750
fb_ioctl+0xe0/0x140
__x64_sys_ioctl+0x193/0x210
do_syscall_64+0x5f/0x9c0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Based on experimentation and analysis, during framebuffer unregistration,
only the memory of fb_info->modelist is freed, without setting the
corresponding fb_display[i]->mode to NULL for the freed modes. This leads
to UAF issues during subsequent accesses. Here's an example of reproduction
steps:
1. With /dev/fb0 already registered in the system, load a kernel module
to register a new device /dev/fb1;
2. Set fb1's mode to the global fb_display[] array (via FBIOPUT_CON2FBMAP);
3. Switch console from fb to VGA (to allow normal rmmod of the ko);
4. Unload the kernel module, at this point fb1's modelist is freed, leaving
a wild pointer in fb_display[];
5. Trigger the bug via system calls through fb0 attempting to delete a mode
from fb0.
Add a check in do_unregister_framebuffer(): if the mode to be freed exists
in fb_display[], set the corresponding mode pointer to NULL.
[ The context change is due to the commit 2c0c19b681
("fbdev: fbmem: Fix double free of 'fb_info->pixmap.addr'") in v5.16
which is irrelevant to the logic of this patch. ]
Signed-off-by: Quanmin Yan <yanquanmin1@huawei.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Johnny Hao <johnny_haocn@sina.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 011a050280 ]
If fbcon_open() fails when called from con2fb_acquire_newinfo() then
info->fbcon_par pointer remains NULL which is later dereferenced.
Add check for return value of the function con2fb_acquire_newinfo() to
avoid it.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: d1baa4ffa6 ("fbcon: set_con2fb_map fixes")
Cc: stable@vger.kernel.org
Signed-off-by: Andrey Vatoropin <a.vatoropin@crpt.ru>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d443d93864 ]
No idea why con2fb_acquire_newinfo() initializes much less than
fbcon_startup(), but so be it. From a quick look most of the
un-initialized stuff should be fairly harmless, but who knows.
Note that the error handling for the con2fb_acquire_newinfo() failure
case was very strange: Callers updated con2fb_map to the new value
before calling this function, but upon error con2fb_acquire_newinfo
reset it to the old value. Since I removed the call to fbcon_release
anyway that strange error path was sticking out like a sore thumb,
hence I removed it. Which also allows us to remove the oldidx
parameter from that function.
v2: Explain what's going on with oldidx and error paths (Sam)
v3: Drop unused variable (0day)
v4: Rebased over bisect fix in previous patch, unchagend end result.
Acked-by: Sam Ravnborg <sam@ravnborg.org> (v2)
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: kernel test robot <lkp@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Claudio Suarez <cssk@net-c.es>
Cc: Du Cheng <ducheng2@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220405210335.3434130-12-daniel.vetter@ffwll.ch
Stable-dep-of: 011a050280 ("fbcon: check return value of con2fb_acquire_newinfo()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bd6026a8c4 ]
There's two minor behaviour changes in here:
- in error paths we now consistently call fb_ops->fb_release
- fb_release really can't fail (fbmem.c ignores it too) and there's no
reasonable cleanup we can do anyway.
Note that everything in fbcon.c is protected by the big console_lock()
lock (especially all the global variables), so the minor changes in
ordering of setup/cleanup do not matter.
v2: Explain a bit better why this is all correct (Sam)
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Claudio Suarez <cssk@net-c.es>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Du Cheng <ducheng2@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220405210335.3434130-10-daniel.vetter@ffwll.ch
Stable-dep-of: 011a050280 ("fbcon: check return value of con2fb_acquire_newinfo()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3b0fb6ab25 ]
Allows us to delete a bunch of hand-rolled stuff using a timer plus a
separate work). Also to simplify the code we initialize the
cursor_work completely when we allocate the fbcon_ops structure,
instead of trying to cope with console re-initialization.
The motiviation here is that fbcon code stops using the fb_info.queue,
which helps with locking issues around cleanup and all that in a later
patch.
Also note that this allows us to ditch the hand-rolled work cleanup in
fbcon_exit - we already call fbcon_del_cursor_timer, which takes care
of everything. Plus this was racy anyway.
v2:
- Only INIT_DELAYED_WORK when kzalloc succeeded (Tetsuo)
- Explain that we replace both the timer and a work with the combined
delayed_work (Javier)
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Claudio Suarez <cssk@net-c.es>
Cc: Du Cheng <ducheng2@gmail.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Link: https://patchwork.freedesktop.org/patch/msgid/20220405210335.3434130-7-daniel.vetter@ffwll.ch
Stable-dep-of: 011a050280 ("fbcon: check return value of con2fb_acquire_newinfo()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b28da0d092 ]
Fix Sun FFB1 corrupted video out ([1] and [2]) by disabling overlay and
initializing window mode to a known state. The issue never appeared on
my FFB2+/vertical nor Elite3D/M6. It could also depend on the PROM
version.
/SUNW,ffb@1e,0: FFB at 000001fc00000000, type 11, DAC pnum[236c] rev[10] manuf_rev[4]
X (II) /dev/fb0: Detected FFB1, Z-buffer, Single-buffered.
X (II) /dev/fb0: BT9068 (PAC1) ramdac detected (with normal cursor control)
X (II) /dev/fb0: Detected Creator/Creator3D
[1] https://www.instagram.com/p/DUTcSmSjSem/
[2] https://chaos.social/@ReneRebe/116023241660154102
Signed-off-by: René Rebe <rene@exactco.de>
Cc: stable@kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 88b3b99243 ]
fbi->fb.screen_buffer is allocated with dma_alloc_coherent() but is not
freed if the error path is reached.
Fixes: e7b995371f ("video: vt8500: Add devicetree support for vt8500-fb and wm8505-fb")
Cc: <stable@vger.kernel.org>
Signed-off-by: Thomas Fourier <fourier.thomas@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ce4e25198a ]
In au1200fb_drv_probe(), when platform_get_irq fails(), it directly
returns from the function with an error code, which causes a memory
leak.
Replace it with a goto label to ensure proper cleanup.
Fixes: 4e88761f5f ("fbdev: au1200fb: Fix missing IRQ check in au1200fb_drv_probe")
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 120adae7b4 upstream.
The UFX_IOCTL_REPORT_DAMAGE ioctl does not properly copy data from
userspace to kernelspace, and instead directly references the memory,
which can cause problems if invalid data is passed from userspace. Fix
this all up by correctly copying the memory before accessing it within
the kernel.
Reported-by: Tianchu Chen <flynnnchen@tencent.com>
Cc: stable <stable@kernel.org>
Cc: Steve Glendinning <steve.glendinning@shawell.net>
Cc: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0209e21e3c upstream.
A userspace program can trigger the RIVA NV3 arbitration code by calling
the FBIOPUT_VSCREENINFO ioctl on /dev/fb*. When doing so, the driver
recomputes FIFO arbitration parameters in nv3_arb(), using state->mclk_khz
(derived from the PRAMDAC MCLK PLL) as a divisor without validating it
first.
In a normal setup, state->mclk_khz is provided by the real hardware and is
non-zero. However, an attacker can construct a malicious or misconfigured
device (e.g. a crafted/emulated PCI device) that exposes a bogus PLL
configuration, causing state->mclk_khz to become zero. Once
nv3_get_param() calls nv3_arb(), the division by state->mclk_khz in the gns
calculation causes a divide error and crashes the kernel.
Fix this by checking whether state->mclk_khz is zero and bailing out before
doing the division.
The following log reveals it:
rivafb: setting virtual Y resolution to 2184
divide error: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 PID: 2187 Comm: syz-executor.0 Not tainted 5.18.0-rc1+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
RIP: 0010:nv3_arb drivers/video/fbdev/riva/riva_hw.c:439 [inline]
RIP: 0010:nv3_get_param+0x3ab/0x13b0 drivers/video/fbdev/riva/riva_hw.c:546
Call Trace:
nv3CalcArbitration.constprop.0+0x255/0x460 drivers/video/fbdev/riva/riva_hw.c:603
nv3UpdateArbitrationSettings drivers/video/fbdev/riva/riva_hw.c:637 [inline]
CalcStateExt+0x447/0x1b90 drivers/video/fbdev/riva/riva_hw.c:1246
riva_load_video_mode+0x8a9/0xea0 drivers/video/fbdev/riva/fbdev.c:779
rivafb_set_par+0xc0/0x5f0 drivers/video/fbdev/riva/fbdev.c:1196
fb_set_var+0x604/0xeb0 drivers/video/fbdev/core/fbmem.c:1033
do_fb_ioctl+0x234/0x670 drivers/video/fbdev/core/fbmem.c:1109
fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1188
__x64_sys_ioctl+0x122/0x190 fs/ioctl.c:856
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0155e868cb upstream.
The variables were never clamped because the return value of clamp_val()
was not used. Fix this by assigning the clamped values, and use clamp()
instead of clamp_val().
Cc: stable@vger.kernel.org
Fixes: 3f16ff608a ("[ARM] pxafb: cleanup of the timing checking code")
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e3f44742bb upstream.
While debuggigng why X would not start on mips64 Sgi/O2 I found the
phys adress being off. Turns out the gbefb passed the internal
dma_addr as phys. May be broken pre git history. Fix by converting
dma_to_phys.
Signed-off-by: René Rebe <rene@exactco.de>
Cc: <stable@vger.kernel.org> # v4.0+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 164312662a ]
The page allocated for vmem using __get_free_pages() is not freed on the
error paths after it. Fix that by adding a corresponding __free_pages()
call to the error path.
Fixes: facd94bc45 ("fbdev: ssd1307fb: Allocate page aligned video memory.")
Signed-off-by: Abdun Nihaal <nihaal@cse.iitm.ac.in>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3637d34b35 ]
Add bounds checking to prevent writes past framebuffer boundaries when
rendering text near screen edges. Return early if the Y position is off-screen
and clip image height to screen boundary. Break from the rendering loop if the
X position is off-screen. When clipping image width to fit the screen, update
the character count to match the clipped width to prevent buffer size
mismatches.
Without the character count update, bit_putcs_aligned and bit_putcs_unaligned
receive mismatched parameters where the buffer is allocated for the clipped
width but cnt reflects the original larger count, causing out-of-bounds writes.
Reported-by: syzbot+48b0652a95834717f190@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=48b0652a95834717f190
Suggested-by: Helge Deller <deller@gmx.de>
Tested-by: syzbot+48b0652a95834717f190@syzkaller.appspotmail.com
Signed-off-by: Albin Babu Varghese <albinbabuvarghese20@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit eb53368f8d upstream.
The of_find_node_by_name() function returns a device tree node with its
reference count incremented. The caller is responsible for calling
of_node_put() to release this reference when done.
Found via static analysis.
Fixes: cc5d0189b9 ("[PATCH] powerpc: Remove device_node addrs/n_addr")
Cc: stable@vger.kernel.org
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5f566c0ac5 upstream.
Commit e24cca19ba ("sh: Kill off MAX_DMA_ADDRESS leftovers.") removed
the define ONCHIP_NR_DMA_CHANNELS. So that the leftover reference needs
to be replaced by CONFIG_NR_ONCHIP_DMA_CHANNELS to compile successfully
with CONFIG_PVR2_DMA enabled.
Signed-off-by: Florian Fuchs <fuchsfl@gmail.com>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 18c4ef4e76 upstream.
bit_putcs_aligned()/unaligned() derived the glyph pointer from the
character value masked by 0xff/0x1ff, which may exceed the actual font's
glyph count and read past the end of the built-in font array.
Clamp the index to the actual glyph count before computing the address.
This fixes a global out-of-bounds read reported by syzbot.
Reported-by: syzbot+793cf822d213be1a74f2@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=793cf822d213be1a74f2
Tested-by: syzbot+793cf822d213be1a74f2@syzkaller.appspotmail.com
Signed-off-by: Junjie Cao <junjie.cao@intel.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7073c7fc8d upstream.
Actually check the return value from pll_ops->init_pll()
as it can return an error.
If the card's BIOS didn't run because it's not the primary VGA card
the fact that the xclk source is unsupported is printed as shown
below but the driver continues on regardless and on my machine causes
a hard lock up.
[ 61.470088] atyfb 0000:03:05.0: enabling device (0080 -> 0083)
[ 61.476191] atyfb: using auxiliary register aperture
[ 61.481239] atyfb: 3D RAGE XL (Mach64 GR, PCI-33) [0x4752 rev 0x27]
[ 61.487569] atyfb: 512K SGRAM (1:1), 14.31818 MHz XTAL, 230 MHz PLL, 83 Mhz MCLK, 63 MHz XCLK
[ 61.496112] atyfb: Unsupported xclk source: 5.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Daniel Palmer <daniel@0x0f.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9b2f5ef00e upstream.
Commit 1a194e6c8e ("fbcon: fix integer overflow in fbcon_do_set_font")
introduced an out-of-bounds access by storing data and allocation sizes
in the same variable. Restore the old size calculation and use the new
variable 'alloc_size' for the allocation.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 1a194e6c8e ("fbcon: fix integer overflow in fbcon_do_set_font")
Reported-by: Jani Nikula <jani.nikula@linux.intel.com>
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/15020
Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6201
Cc: Samasth Norway Ananda <samasth.norway.ananda@oracle.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: George Kennedy <george.kennedy@oracle.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Simona Vetter <simona@ffwll.ch>
Cc: Helge Deller <deller@gmx.de>
Cc: "Ville Syrjälä" <ville.syrjala@linux.intel.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Qianqiang Liu <qianqiang.liu@163.com>
Cc: Shixiong Ou <oushixiong@kylinos.cn>
Cc: Kees Cook <kees@kernel.org>
Cc: <stable@vger.kernel.org> # v5.9+
Cc: Zsolt Kajtar <soci@c64.rulez.org>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Qianqiang Liu <qianqiang.liu@163.com>
Link: https://lore.kernel.org/r/20250922134619.257684-1-tzimmermann@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1a194e6c8e upstream.
Fix integer overflow vulnerabilities in fbcon_do_set_font() where font
size calculations could overflow when handling user-controlled font
parameters.
The vulnerabilities occur when:
1. CALC_FONTSZ(h, pitch, charcount) performs h * pith * charcount
multiplication with user-controlled values that can overflow.
2. FONT_EXTRA_WORDS * sizeof(int) + size addition can also overflow
3. This results in smaller allocations than expected, leading to buffer
overflows during font data copying.
Add explicit overflow checking using check_mul_overflow() and
check_add_overflow() kernel helpers to safety validate all size
calculations before allocation.
Signed-off-by: Samasth Norway Ananda <samasth.norway.ananda@oracle.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 39b3cffb8c ("fbcon: prevent user font height or width change from causing potential out-of-bounds access")
Cc: George Kennedy <george.kennedy@oracle.com>
Cc: stable <stable@vger.kernel.org>
Cc: syzbot+38a3699c7eaf165b97a6@syzkaller.appspotmail.com
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Simona Vetter <simona@ffwll.ch>
Cc: Helge Deller <deller@gmx.de>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: "Ville Syrjälä" <ville.syrjala@linux.intel.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Qianqiang Liu <qianqiang.liu@163.com>
Cc: Shixiong Ou <oushixiong@kylinos.cn>
Cc: Kees Cook <kees@kernel.org>
Cc: <stable@vger.kernel.org> # v5.9+
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20250912170023.3931881-1-samasth.norway.ananda@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 13d28e0c79.
Commit ee7a69aa38 ("fbdev: Disable sysfb device registration when
removing conflicting FBs") was backported to 5.15.y LTS. This causes a
regression where all virtual consoles stop responding during boot at:
"Populating /dev with existing devices through uevents ..."
Reverting the commit fixes the regression.
Signed-off-by: Brett A C Sheffield <bacs@librecast.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit af0db3c1f8 upstream.
This issue triggers when a userspace program does an ioctl
FBIOPUT_CON2FBMAP by passing console number and frame buffer number.
Ideally this maps console to frame buffer and updates the screen if
console is visible.
As part of mapping it has to do resize of console according to frame
buffer info. if this resize fails and returns from vc_do_resize() and
continues further. At this point console and new frame buffer are mapped
and sets display vars. Despite failure still it continue to proceed
updating the screen at later stages where vc_data is related to previous
frame buffer and frame buffer info and display vars are mapped to new
frame buffer and eventully leading to out-of-bounds write in
fast_imageblit(). This bheviour is excepted only when fg_console is
equal to requested console which is a visible console and updates screen
with invalid struct references in fbcon_putcs().
Reported-and-tested-by: syzbot+c4b7aa0513823e2ea880@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c4b7aa0513823e2ea880
Signed-off-by: Sravan Kumar Gundu <sravankumarlpu@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit da11e6a30e ]
fb_add_videomode() can fail with -ENOMEM when its internal kmalloc() cannot
allocate a struct fb_modelist. If that happens, the modelist stays empty but
the driver continues to register. Add a check for its return value to prevent
poteintial null-ptr-deref, which is similar to the commit 17186f1f90 ("fbdev:
Fix do_register_framebuffer to prevent null-ptr-deref in fb_videomode_to_var").
Fixes: 1b6c79361b ("video: imxfb: Add DT support")
Signed-off-by: Chenyuan Yang <chenyuan0y@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8d5cc8eed7 ]
The non-zero (true) return value from consw::con_switch() means a redraw
is needed. So make this return type a bool explicitly instead of int.
The latter might imply that -Eerrors are expected. They are not.
And document the hook.
Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-parisc@vger.kernel.org
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-31-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 03bcbbb399 ("dummycon: Trigger redraw when switching consoles with deferred takeover")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 559f01a0ee ]
In consw::con_clear():
* Height is always 1, so drop it.
* Offsets and width are always unsigned values, so re-type them as such.
This needs a new __fbcon_clear() in the fbcon code to still handle
height which might not be 1 when called internally.
Note that tests for negative count/width are left in place -- they are
taken care of in the next patches.
And document the hook.
Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-parisc@vger.kernel.org
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-22-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 03bcbbb399 ("dummycon: Trigger redraw when switching consoles with deferred takeover")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit dae3e6b618 ]
The 'init' parameter of consw::con_init() is true for the first call of
the hook on a particular console. So make the parameter a bool.
And document the hook.
Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linux-parisc@vger.kernel.org
Tested-by: Helge Deller <deller@gmx.de> # parisc STI console
Link: https://lore.kernel.org/r/20240122110401.7289-21-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable-dep-of: 03bcbbb399 ("dummycon: Trigger redraw when switching consoles with deferred takeover")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9ad7acdad1 ]
I didn't bother with any code movement to fix the others, these just
got a bit in the way.
v2: Rebase on top of Helge's reverts.
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org> (v1)
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> (v1)
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Du Cheng <ducheng2@gmail.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Claudio Suarez <cssk@net-c.es>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220405210335.3434130-2-daniel.vetter@ffwll.ch
Stable-dep-of: 03bcbbb399 ("dummycon: Trigger redraw when switching consoles with deferred takeover")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 05f6e18387 upstream.
If fb_add_videomode() in fb_set_var() fails to allocate memory for
fb_videomode, later it may lead to a null-ptr dereference in
fb_videomode_to_var(), as the fb_info is registered while not having the
mode in modelist that is expected to be there, i.e. the one that is
described in fb_info->var.
================================================================
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 PID: 30371 Comm: syz-executor.1 Not tainted 5.10.226-syzkaller #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:fb_videomode_to_var+0x24/0x610 drivers/video/fbdev/core/modedb.c:901
Call Trace:
display_to_var+0x3a/0x7c0 drivers/video/fbdev/core/fbcon.c:929
fbcon_resize+0x3e2/0x8f0 drivers/video/fbdev/core/fbcon.c:2071
resize_screen drivers/tty/vt/vt.c:1176 [inline]
vc_do_resize+0x53a/0x1170 drivers/tty/vt/vt.c:1263
fbcon_modechanged+0x3ac/0x6e0 drivers/video/fbdev/core/fbcon.c:2720
fbcon_update_vcs+0x43/0x60 drivers/video/fbdev/core/fbcon.c:2776
do_fb_ioctl+0x6d2/0x740 drivers/video/fbdev/core/fbmem.c:1128
fb_ioctl+0xe7/0x150 drivers/video/fbdev/core/fbmem.c:1203
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+0x19a/0x210 fs/ioctl.c:739
do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x67/0xd1
================================================================
The reason is that fb_info->var is being modified in fb_set_var(), and
then fb_videomode_to_var() is called. If it fails to add the mode to
fb_info->modelist, fb_set_var() returns error, but does not restore the
old value of fb_info->var. Restore fb_info->var on failure the same way
it is done earlier in the function.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Murad Masimov <m.masimov@mt-integration.ru>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3f6dae09fc ]
In fb_find_mode_cvt(), iff mode->refresh somehow happens to be 0x80000000,
cvt.f_refresh will become 0 when multiplying it by 2 due to overflow. It's
then passed to fb_cvt_hperiod(), where it's used as a divider -- division
by 0 will result in kernel oops. Add a sanity check for cvt.f_refresh to
avoid such overflow...
Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.
Fixes: 96fe6a2109 ("[PATCH] fbdev: Add VESA Coordinated Video Timings (CVT) support")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 76d3ca8998 ]
I was wondering why there's garbage at the bottom of the screen when
tile blitting is used with an odd mode like 1080, 600 or 200. Sure there's
only space for half a tile but the same area is clean when the buffer
is bitmap.
Then later I found that it's supposed to be cleaned but that's not
implemented. So I took what's in bitblit and adapted it for tileblit.
This implementation was tested for both the horizontal and vertical case,
and now does the same as what's done for bitmap buffers.
If anyone is interested to reproduce the problem then I could bet that'd
be on a S3 or Ark. Just set up a mode with an odd line count and make
sure that the virtual size covers the complete tile at the bottom. E.g.
for 600 lines that's 608 virtual lines for a 16 tall tile. Then the
bottom area should be cleaned.
For the right side it's more difficult as there the drivers won't let an
odd size happen, unless the code is modified. But once it reports back a
few pixel columns short then fbcon won't use the last column. With the
patch that column is now clean.
Btw. the virtual size should be rounded up by the driver for both axes
(not only the horizontal) so that it's dividable by the tile size.
That's a driver bug but correcting it is not in scope for this patch.
Implement missing margin clearing for tileblit
Signed-off-by: Zsolt Kajtar <soci@c64.rulez.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 892c788d73 ]
The erase colour calculation for fbcon clearing should use get_color instead
of attr_col_ec, like everything else. The latter is similar but is not correct.
For example it's missing the depth dependent remapping and doesn't care about
blanking.
The problem can be reproduced by setting up the background colour to grey
(vt.color=0x70) and having an fbcon console set to 2bpp (4 shades of gray).
Now the background attribute should be 1 (dark gray) on the console.
If the screen is scrolled when pressing enter in a shell prompt at the bottom
line then the new line is cleared using colour 7 instead of 1. That's not
something fillrect likes (at 2bbp it expect 0-3) so the result is interesting.
This patch switches to get_color with vc_video_erase_char to determine the
erase colour from attr_col_ec. That makes the latter function redundant as
no other users were left.
Use correct erase colour for clearing in fbcon
Signed-off-by: Zsolt Kajtar <soci@c64.rulez.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3e411827f3 ]
Function dispc_ovl_setup is not intended to work with the value OMAP_DSS_WB
of the enum parameter plane.
The value of this parameter is initialized in dss_init_overlays and in the
current state of the code it cannot take this value so it's not a real
problem.
For the purposes of defensive coding it wouldn't be superfluous to check
the parameter value, because some functions down the call stack process
this value correctly and some not.
For example, in dispc_ovl_setup_global_alpha it may lead to buffer
overflow.
Add check for this value.
Found by Linux Verification Center (linuxtesting.org) with SVACE static
analysis tool.
Signed-off-by: Leonid Arapov <arapovl839@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit aee50bd88e ]
Added checks for xoffset, yoffset settings.
Incorrect settings of these parameters can lead to errors
in sm501fb_pan_ functions.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 5fc404e47b ("[PATCH] fb: SM501 framebuffer driver")
Signed-off-by: Danila Chernetsov <listdansp@mail.ru>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2df2c0caae ]
The address of a data structure member was determined before
a corresponding null pointer check in the implementation of
the function “au1100fb_setmode”.
This issue was detected by using the Coccinelle software.
Fixes: 3b495f2bb7 ("Au1100 FB driver uplift for 2.6.")
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7241c886a7 ]
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 d21987d709 ("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: d21987d709 ("video: hyperv: hyperv_fb: Support deferred IO for Hyper-V frame buffer driver")
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Reviewed-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Link: https://lore.kernel.org/r/20250209235252.2987-1-mhklinux@outlook.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20250209235252.2987-1-mhklinux@outlook.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit de124b61e1 ]
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: f76ee892a9 ("omapfb: copy omapdss & displays for omapfb")
Signed-off-by: Joe Hattori <joe@pf.is.s.u-tokyo.ac.jp>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8404e56f4b ]
Pass the hardware device to the DMA helpers dma_alloc_coherent() and
dma_free_coherent(). The fbdev device that is currently being used is
a software device and does not provide DMA memory. Also update the
related dev_*() output statements similarly.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230613110953.24176-28-tzimmermann@suse.de
Stable-dep-of: f89d17ae2a ("fbdev: sh7760fb: Fix a possible memory leak in sh7760fb_alloc_mem()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9cf14f5a27 ]
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 <shum.sdl@nppct.ru>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4a6921095e ]
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 <kxwang23@m.fudan.edu.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit aa578e8975 ]
If an error occurs after request_mem_region(), a corresponding
release_mem_region() should be called, as already done in the remove
function.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 6ad959b670 upstream.
The commit 04e5eac8f3ab("fbdev: savage: Error out if pixclock equals zero")
checks the value of pixclock to avoid divide-by-zero error. However
the function savagefb_probe doesn't handle the error return of
savagefb_check_var. When pixclock is 0, it will cause divide-by-zero error.
Fixes: 04e5eac8f3 ("fbdev: savage: Error out if pixclock equals zero")
Signed-off-by: Cai Xinchen <caixinchen1@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 51084f89d6 ]
There is no reason to prohibit sh7760fb from being built as a
loadable module as suggested by Geert, so change the config symbol
from bool to tristate to allow that and change the FB dependency as
needed.
Fixes: f75f71b2c4 ("fbdev/sh7760fb: Depend on FB=y")
Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Acked-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Acked-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 688cf59866 ]
Building with W=1 shows that a couple of variables in this driver are only
used in certain configurations:
drivers/video/fbdev/sis/init301.c:239:28: error: 'SiS_Part2CLVX_6' defined but not used [-Werror=unused-const-variable=]
239 | static const unsigned char SiS_Part2CLVX_6[] = { /* 1080i */
| ^~~~~~~~~~~~~~~
drivers/video/fbdev/sis/init301.c:230:28: error: 'SiS_Part2CLVX_5' defined but not used [-Werror=unused-const-variable=]
230 | static const unsigned char SiS_Part2CLVX_5[] = { /* 750p */
| ^~~~~~~~~~~~~~~
drivers/video/fbdev/sis/init301.c:211:28: error: 'SiS_Part2CLVX_4' defined but not used [-Werror=unused-const-variable=]
211 | static const unsigned char SiS_Part2CLVX_4[] = { /* PAL */
| ^~~~~~~~~~~~~~~
drivers/video/fbdev/sis/init301.c:192:28: error: 'SiS_Part2CLVX_3' defined but not used [-Werror=unused-const-variable=]
192 | static const unsigned char SiS_Part2CLVX_3[] = { /* NTSC, 525i, 525p */
| ^~~~~~~~~~~~~~~
drivers/video/fbdev/sis/init301.c:184:28: error: 'SiS_Part2CLVX_2' defined but not used [-Werror=unused-const-variable=]
184 | static const unsigned char SiS_Part2CLVX_2[] = {
| ^~~~~~~~~~~~~~~
drivers/video/fbdev/sis/init301.c:176:28: error: 'SiS_Part2CLVX_1' defined but not used [-Werror=unused-const-variable=]
176 | static const unsigned char SiS_Part2CLVX_1[] = {
| ^~~~~~~~~~~~~~~
This started showing up after the definitions were moved into the
source file from the header, which was not flagged by the compiler.
Move the definition into the appropriate #ifdef block that already
exists next to them.
Fixes: 5908986ef3 ("video: fbdev: sis: avoid mismatched prototypes")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 26c8cfb9d1 ]
The name of the overlay does not fit into the fixed-length field:
drivers/video/fbdev/sh_mobile_lcdcfb.c:1577:2: error: 'snprintf' will always be truncated; specified size is 16, but format string expands to at least 25
Make it short enough by changing the string.
Fixes: c5deac3c9b ("fbdev: sh_mobile_lcdc: Implement overlays support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 78d9161d2b upstream.
With deferred IO enabled, a page fault happens when data is written to the
framebuffer device. Then driver determines which page is being updated by
calculating the offset of the written virtual address within the virtual
memory area, and uses this offset to get the updated page within the
internal buffer. This page is later copied to hardware (thus the name
"deferred IO").
This offset calculation is only correct if the virtual memory area is
mapped to the beginning of the internal buffer. Otherwise this is wrong.
For example, if users do:
mmap(ptr, 4096, PROT_WRITE, MAP_FIXED | MAP_SHARED, fd, 0xff000);
Then the virtual memory area will mapped at offset 0xff000 within the
internal buffer. This offset 0xff000 is not accounted for, and wrong page
is updated.
Correct the calculation by using vmf->pgoff instead. With this change, the
variable "offset" will no longer hold the exact offset value, but it is
rounded down to multiples of PAGE_SIZE. But this is still correct, because
this variable is only used to calculate the page offset.
Reported-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Closes: https://lore.kernel.org/linux-fbdev/271372d6-e665-4e7f-b088-dee5f4ab341a@oracle.com
Fixes: 56c134f7f1 ("fbdev: Track deferred-I/O pages in pageref struct")
Cc: <stable@vger.kernel.org>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20240423115053.4490-1-namcao@linutronix.de
[rebase to v5.15]
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit c2d953276b ]
The expression htotal * vtotal can have a zero value on
overflow. It is necessary to prevent division by zero like in
fb_var_to_videomode().
Found by Linux Verification Center (linuxtesting.org) with Svace.
Signed-off-by: Roman Smirnov <r.smirnov@omp.ru>
Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bc87bb342f ]
There are some actions with value 'tmp' but 'dst_addr' is checked instead.
It is obvious that a copy-paste error was made here and the value
of variable 'tmp' should be checked here.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Signed-off-by: Aleksandr Burakov <a.burakov@rosalinux.ru>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
