[ Upstream commit 6d1c32dbedd7d7e7372aa38033ec8782c39f6379 ]
device_for_each_child_node() bumps a reference counting of a returned variable.
We have to balance it whenever we return to the caller.
Cc: Brian Masney <masneyb@onstation.org>
Cc: Dan Murphy <dmurphy@ti.com>
Fixes: 8fbce8efe15cd ("backlight: lm3630a: Add firmware node support")
Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Brian Masney <masneyb@onstation.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 767d724a160eb1cd00c86fb8c2e21fa1ab3c37ac ]
'ret' is known to be 0 here.
No error code is available, so just remove it from the error message.
Fixes: 72330b0eeefc ("i.MX Framebuffer: Use readl/writel instead of direct pointer deref")
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/d7b25026f82659da3c6f7159eea480faa9d738be.1620327302.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Sasha Levin <sashal@kernel.org>
Commit ccf953d8f3d6 makes framebuffers which use deferred I/O stop displaying updates after the first one. This is because the pages handled by fb_defio no longer have a page_mapping(). That prevents page_mkclean() from marking the PTEs as clean, and so writes are only noticed the first time. Reported-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/YLZEhv0cpZp8uVE3@casper.infradead.org
The return value of hga_card_detect() is not properly handled causing
the probe to succeed even though hga_card_detect() failed. Since probe
succeeds, hgafb_open() can be called which will end up operating on an
unmapped hga_vram. This results in an out-of-bounds access as reported
by kernel test robot [1].
To fix this, correctly detect failure of hga_card_detect() by checking
for a non-zero error code.
[1]: https://lore.kernel.org/lkml/20210516150019.GB25903@xsang-OptiPlex-9020/
Fixes: dc13cac4862c ("video: hgafb: fix potential NULL pointer dereference")
Cc: stable <stable@vger.kernel.org>
Reported-by: kernel test robot <oliver.sang@intel.com>
Reviewed-by: Igor Matheus Andrade Torrente <igormtorrente@gmail.com>
Signed-off-by: Anirudh Rayabharam <mail@anirudhrb.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20210516192714.25823-1-mail@anirudhrb.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull char/misc driver fixes from Greg KH: "Here is a big set of char/misc/other driver fixes for 5.13-rc3. The majority here is the fallout of the umn.edu re-review of all prior submissions. That resulted in a bunch of reverts along with the "correct" changes made, such that there is no regression of any of the potential fixes that were made by those individuals. I would like to thank the over 80 different developers who helped with the review and fixes for this mess. Other than that, there's a few habanna driver fixes for reported issues, and some dyndbg fixes for reported problems. All of these have been in linux-next for a while with no reported problems" * tag 'char-misc-5.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (82 commits) misc: eeprom: at24: check suspend status before disable regulator uio_hv_generic: Fix another memory leak in error handling paths uio_hv_generic: Fix a memory leak in error handling paths uio/uio_pci_generic: fix return value changed in refactoring Revert "Revert "ALSA: usx2y: Fix potential NULL pointer dereference"" dyndbg: drop uninformative vpr_info dyndbg: avoid calling dyndbg_emit_prefix when it has no work binder: Return EFAULT if we fail BINDER_ENABLE_ONEWAY_SPAM_DETECTION cdrom: gdrom: initialize global variable at init time brcmfmac: properly check for bus register errors Revert "brcmfmac: add a check for the status of usb_register" video: imsttfb: check for ioremap() failures Revert "video: imsttfb: fix potential NULL pointer dereferences" net: liquidio: Add missing null pointer checks Revert "net: liquidio: fix a NULL pointer dereference" media: gspca: properly check for errors in po1030_probe() Revert "media: gspca: Check the return value of write_bridge for timeout" media: gspca: mt9m111: Check write_bridge for timeout Revert "media: gspca: mt9m111: Check write_bridge for timeout" media: dvb: Add check on sp8870_readreg return ...
syzbot is reporting OOB write at vga16fb_imageblit() [1], for
resize_screen() from ioctl(VT_RESIZE) returns 0 without checking whether
requested rows/columns fit the amount of memory reserved for the graphical
screen if current mode is KD_GRAPHICS.
----------
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/kd.h>
#include <linux/vt.h>
int main(int argc, char *argv[])
{
const int fd = open("/dev/char/4:1", O_RDWR);
struct vt_sizes vt = { 0x4100, 2 };
ioctl(fd, KDSETMODE, KD_GRAPHICS);
ioctl(fd, VT_RESIZE, &vt);
ioctl(fd, KDSETMODE, KD_TEXT);
return 0;
}
----------
Allow framebuffer drivers to return -EINVAL, by moving vc->vc_mode !=
KD_GRAPHICS check from resize_screen() to fbcon_resize().
Link: https://syzkaller.appspot.com/bug?extid=1f29e126cf461c4de3b3 [1]
Reported-by: syzbot <syzbot+1f29e126cf461c4de3b3@syzkaller.appspotmail.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: syzbot <syzbot+1f29e126cf461c4de3b3@syzkaller.appspotmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge VT_RESIZEX fixes from Maciej Rozycki: "I got to the bottom of the issue with VT_RESIZEX recently discussed and came up with this small patch series, fixing an additional issue that I originally thought might be broken VGA hardware emulation with my laptop, which however turned out to be intertwined with the original problem and also a regression introduced somewhat later. The fix for that because the first patch, and then to make backporting feasible I had to put a revert of the offending change from last September next, followed by a proper fix for the framebuffer issue that change had tried to address. See individual change descriptions for details. These have been verified with true VGA hardware (a Trident TVGA8900 ISA video adapter) using various combinations of `svgatextmode' and `setfont' command invocations to change both the VT size and the font size, and also switching between the text console and X11, both by starting/stopping the X server and by switching between VTs. All this to ensure bringing the behaviour of VGA text console back to correct operation as it used to be with Linux 2.6.18" * emailed patches from Maciej W. Rozycki <macro@orcam.me.uk>: vt: Fix character height handling with VT_RESIZEX vt_ioctl: Revert VT_RESIZEX parameter handling removal vgacon: Record video mode changes with VT_RESIZEX
Restore the original intent of the VT_RESIZEX ioctl's `v_clin' parameter
which is the number of pixel rows per character (cell) rather than the
height of the font used.
For framebuffer devices the two values are always the same, because the
former is inferred from the latter one. For VGA used as a true text
mode device these two parameters are independent from each other: the
number of pixel rows per character is set in the CRT controller, while
font height is in fact hardwired to 32 pixel rows and fonts of heights
below that value are handled by padding their data with blanks when
loaded to hardware for use by the character generator. One can change
the setting in the CRT controller and it will update the screen contents
accordingly regardless of the font loaded.
The `v_clin' parameter is used by the `vgacon' driver to set the height
of the character cell and then the cursor position within. Make the
parameter explicit then, by defining a new `vc_cell_height' struct
member of `vc_data', set it instead of `vc_font.height' from `v_clin' in
the VT_RESIZEX ioctl, and then use it throughout the `vgacon' driver
except where actual font data is accessed which as noted above is
independent from the CRTC setting.
This way the framebuffer console driver is free to ignore the `v_clin'
parameter as irrelevant, as it always should have, avoiding any issues
attempts to give the parameter a meaning there could have caused, such
as one that has led to commit 988d0763361b ("vt_ioctl: make VT_RESIZEX
behave like VT_RESIZE"):
"syzbot is reporting UAF/OOB read at bit_putcs()/soft_cursor() [1][2],
for vt_resizex() from ioctl(VT_RESIZEX) allows setting font height
larger than actual font height calculated by con_font_set() from
ioctl(PIO_FONT). Since fbcon_set_font() from con_font_set() allocates
minimal amount of memory based on actual font height calculated by
con_font_set(), use of vt_resizex() can cause UAF/OOB read for font
data."
The problem first appeared around Linux 2.5.66 which predates our repo
history, but the origin could be identified with the old MIPS/Linux repo
also at: <git://git.kernel.org/pub/scm/linux/kernel/git/ralf/linux.git>
as commit 9736a3546de7 ("Merge with Linux 2.5.66."), where VT_RESIZEX
code in `vt_ioctl' was updated as follows:
if (clin)
- video_font_height = clin;
+ vc->vc_font.height = clin;
making the parameter apply to framebuffer devices as well, perhaps due
to the use of "font" in the name of the original `video_font_height'
variable. Use "cell" in the new struct member then to avoid ambiguity.
References:
[1] https://syzkaller.appspot.com/bug?id=32577e96d88447ded2d3b76d71254fb855245837
[2] https://syzkaller.appspot.com/bug?id=6b8355d27b2b94fb5cedf4655e3a59162d9e48e3
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org # v2.6.12+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix an issue with VGA console font size changes made after the initial
video text mode has been changed with a user tool like `svgatextmode'
calling the VT_RESIZEX ioctl. As it stands in that case the original
screen geometry continues being used to validate further VT resizing.
Consequently when the video adapter is firstly reprogrammed from the
original say 80x25 text mode using a 9x16 character cell (720x400 pixel
resolution) to say 80x37 text mode and the same character cell (720x592
pixel resolution), and secondly the CRTC character cell updated to 9x8
(by loading a suitable font with the KD_FONT_OP_SET request of the
KDFONTOP ioctl), the VT geometry does not get further updated from 80x37
and only upper half of the screen is used for the VT, with the lower
half showing rubbish corresponding to whatever happens to be there in
the video memory that maps to that part of the screen. Of course the
proportions change according to text mode geometries and font sizes
chosen.
Address the problem then, by updating the text mode geometry defaults
rather than checking against them whenever the VT is resized via a user
ioctl.
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Fixes: e400b6ec4ede ("vt/vgacon: Check if screen resize request comes from userspace")
Cc: stable@vger.kernel.org # v2.6.24+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We should check if ioremap() were to somehow fail in imsttfb_probe() and handle the unwinding of the resources allocated here properly. Ideally if anyone cares about this driver (it's for a PowerMac era PCI display card), they wouldn't even be using fbdev anymore. Or the devm_* apis could be used, but that's just extra work for diminishing returns... Cc: Finn Thain <fthain@telegraphics.com.au> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Reviewed-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/20210503115736.2104747-68-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>