Kernel Tree For Xiaomi 11 Lite NE 5G
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Letu Ren 7d9591b32a fbdev: fb_pm2fb: Avoid potential divide by zero error
commit 19f953e7435644b81332dd632ba1b2d80b1e37af upstream.

In `do_fb_ioctl()` of fbmem.c, if cmd is FBIOPUT_VSCREENINFO, var will be
copied from user, then go through `fb_set_var()` and
`info->fbops->fb_check_var()` which could may be `pm2fb_check_var()`.
Along the path, `var->pixclock` won't be modified. This function checks
whether reciprocal of `var->pixclock` is too high. If `var->pixclock` is
zero, there will be a divide by zero error. So, it is necessary to check
whether denominator is zero to avoid crash. As this bug is found by
Syzkaller, logs are listed below.

divide error in pm2fb_check_var
Call Trace:
 <TASK>
 fb_set_var+0x367/0xeb0 drivers/video/fbdev/core/fbmem.c:1015
 do_fb_ioctl+0x234/0x670 drivers/video/fbdev/core/fbmem.c:1110
 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1189

Reported-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Letu Ren <fantasquex@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-05 10:27:45 +02:00
arch x86/bugs: Add "unknown" reporting for MMIO Stale Data 2022-09-05 10:27:45 +02:00
block blk-mq: don't create hctx debugfs dir until q->debugfs_dir is created 2022-08-25 11:17:36 +02:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:11:22 +02:00
crypto crypto: drbg - make reseeding from get_random_bytes() synchronous 2022-06-22 14:11:18 +02:00
Documentation x86/bugs: Add "unknown" reporting for MMIO Stale Data 2022-09-05 10:27:45 +02:00
drivers fbdev: fb_pm2fb: Avoid potential divide by zero error 2022-09-05 10:27:45 +02:00
fs btrfs: check if root is readonly while setting security xattr 2022-09-05 10:27:43 +02:00
include asm-generic: sections: refactor memory_intersects 2022-09-05 10:27:43 +02:00
init random: handle latent entropy and command line from random_init() 2022-06-22 14:11:17 +02:00
ipc ipc/mqueue: use get_tree_nodev() in mqueue_get_tree() 2022-06-14 18:11:41 +02:00
kernel sched/deadline: Fix priority inheritance with multiple scheduling classes 2022-09-05 10:27:39 +02:00
lib ratelimit: Fix data-races in ___ratelimit(). 2022-09-05 10:27:42 +02:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm mm: Force TLB flush for PFNMAP mappings before unlink_file_vma() 2022-09-05 10:27:44 +02:00
net Bluetooth: L2CAP: Fix build errors in some archs 2022-09-05 10:27:45 +02:00
samples samples/kretprobes: Fix return value if register_kretprobe() failed 2021-11-17 09:48:39 +01:00
scripts kbuild: Fix include path in scripts/Makefile.modpost 2022-09-05 10:27:45 +02:00
security apparmor: Fix memleak in aa_simple_write_to_buffer() 2022-08-25 11:18:21 +02:00
sound ALSA: timer: Use deferred fasync helper 2022-08-25 11:18:38 +02:00
tools Revert "selftests/bpf: Fix test_align verifier log patterns" 2022-09-05 10:27:39 +02:00
usr initramfs: restore default compression behavior 2020-04-08 09:08:38 +02:00
virt KVM: Add infrastructure and macro to mark VM as bugged 2022-08-25 11:18:16 +02:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Modules updates for v5.4 2019-09-22 10:34:46 -07:00
.mailmap ARM: SoC fixes 2019-11-10 13:41:59 -08:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS: Remove Simon as Renesas SoC Co-Maintainer 2019-10-10 08:12:51 -07:00
Kbuild kbuild: do not descend to ./Kbuild when cleaning 2019-08-21 21:03:58 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS MAINTAINERS: co-maintain random.c 2022-06-22 14:11:05 +02:00
Makefile Linux 5.4.211 2022-08-25 11:18:40 +02:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.