fbdev: fb_pm2fb: Avoid potential divide by zero error
In the Linux kernel, the following vulnerability has been resolved:
fbdev: fb_pm2fb: Avoid potential divide by zero error
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 e
ftrace: Fix NULL pointer dereference in is_ftrace_trampoline when ftrace is dead
In the Linux kernel, the following vulnerability has been resolved:
ftrace: Fix NULL pointer dereference in is_ftrace_trampoline when ftrace is dead
ftrace_startup does not remove ops from ftrace_ops_list when
ftrace_startup_enable fails:
register_ftrace_function
ftrace_startup
__register_ftrace_function
...
add_ftrace_ops(&ftrace_ops_list, ops)
...
...
ftrace_startup_enable // if ftrace failed to modify, ftrace_disabled is set to 1
...
return 0 // ops is in the ftrace_ops_list.
When ftrace_disabled = 1, unregister_ftrace_function simply returns without doing anything:
unregister_ftrace_function
ftr
In the Linux kernel, the following vulnerability has been resolved:
bpf: Don't redirect packets with invalid pkt_len
Syzbot found an issue [1]: fq_codel_drop() try to drop a flow whitout any
skbs, that is, the flow->head is null.
The root cause, as the [2] says, is because that bpf_prog_test_run_skb()
run a bpf prog which redirects empty skbs.
So we should determine whether the length of the packet modified by bpf
prog or others like bpf_prog_test is valid before forwarding it directly.
drm/amd/display: clear optc underflow before turn off odm clock
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: clear optc underflow before turn off odm clock
[Why]
After ODM clock off, optc underflow bit will be kept there always and clear not work.
We need to clear that before clock off.
[How]
Clear that if have when clock off.
In the Linux kernel, the following vulnerability has been resolved:
ieee802154/adf7242: defer destroy_workqueue call
There is a possible race condition (use-after-free) like below
(FREE) | (USE)
adf7242_remove | adf7242_channel
cancel_delayed_work_sync |
destroy_workqueue (1) | adf7242_cmd_rx
| mod_delayed_work (2)
|
The root cause for this race is that the upper layer (ieee802154) is
unaware of this detaching event and the function adf7242_channel can
be called without any checks.
To fix this, we can add a flag write at the be
arm64: cacheinfo: Fix incorrect assignment of signed error value to unsigned fw_level
In the Linux kernel, the following vulnerability has been resolved:
arm64: cacheinfo: Fix incorrect assignment of signed error value to unsigned fw_level
Though acpi_find_last_cache_level() always returned signed value and the
document states it will return any errors caused by lack of a PPTT table,
it never returned negative values before.
Commit 0c80f9e165f8 ("ACPI: PPTT: Leave the table mapped for the runtime usage")
however changed it by returning -ENOENT if no PPTT was found. The value
returned from acpi_find_last_cache_level() is then assigned to unsigned
fw_level.
It will result in the number of cache leaves calculated incorrectly
In the Linux kernel, the following vulnerability has been resolved:
kcm: fix strp_init() order and cleanup
strp_init() is called just a few lines above this csk->sk_user_data
check, it also initializes strp->work etc., therefore, it is
unnecessary to call strp_done() to cancel the freshly initialized
work.
And if sk_user_data is already used by KCM, psock->strp should not be
touched, particularly strp->work state, so we need to move strp_init()
after the csk->sk_user_data check.
This also makes a lockdep warning reported by syzbot go away.
In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8712: fix use after free bugs
_Read/Write_MACREG callbacks are NULL so the read/write_macreg_hdl()
functions don't do anything except free the "pcmd" pointer. It
results in a use after free. Delete them.
Input: iforce - wake up after clearing IFORCE_XMIT_RUNNING flag
In the Linux kernel, the following vulnerability has been resolved:
Input: iforce - wake up after clearing IFORCE_XMIT_RUNNING flag
syzbot is reporting hung task at __input_unregister_device() [1], for
iforce_close() waiting at wait_event_interruptible() with dev->mutex held
is blocking input_disconnect_device() from __input_unregister_device().
It seems that the cause is simply that commit c2b27ef672992a20 ("Input:
iforce - wait for command completion when closing the device") forgot to
call wake_up() after clear_bit().
Fix this problem by introducing a helper that calls clear_bit() followed
by wake_up_all().
In the Linux kernel, the following vulnerability has been resolved:
misc: fastrpc: fix memory corruption on probe
Add the missing sanity check on the probed-session count to avoid
corrupting memory beyond the fixed-size slab-allocated session array
when there are more than FASTRPC_MAX_SESSIONS sessions defined in the
devicetree.
In the Linux kernel, the following vulnerability has been resolved:
misc: fastrpc: fix memory corruption on open
The probe session-duplication overflow check incremented the session
count also when there were no more available sessions so that memory
beyond the fixed-size slab-allocated session array could be corrupted in
fastrpc_session_alloc() on open().
In the Linux kernel, the following vulnerability has been resolved:
vt: Clear selection before changing the font
When changing the console font with ioctl(KDFONTOP) the new font size
can be bigger than the previous font. A previous selection may thus now
be outside of the new screen size and thus trigger out-of-bounds
accesses to graphics memory if the selection is removed in
vc_do_resize().
Prevent such out-of-memory accesses by dropping the selection before the
various con_font_set() console handlers are called.
In the Linux kernel, the following vulnerability has been resolved:
hwmon: (gpio-fan) Fix array out of bounds access
The driver does not check if the cooling state passed to
gpio_fan_set_cur_state() exceeds the maximum cooling state as
stored in fan_data->num_speeds. Since the cooling state is later
used as an array index in set_fan_speed(), an array out of bounds
access can occur.
This can be exploited by setting the state of the thermal cooling device
to arbitrary values, causing for example a kernel oops when unavailable
memory is accessed this way.
Example kernel oops:
[ 807.987276] Unable to handle kernel paging request at virtual ad
wifi: mac80211: Don't finalize CSA in IBSS mode if state is disconnected
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: Don't finalize CSA in IBSS mode if state is disconnected
When we are not connected to a channel, sending channel "switch"
announcement doesn't make any sense.
The BSS list is empty in that case. This causes the for loop in
cfg80211_get_bss() to be bypassed, so the function returns NULL
(check line 1424 of net/wireless/scan.c), causing the WARN_ON()
in ieee80211_ibss_csa_beacon() to get triggered (check line 500
of net/mac80211/ibss.c), which was consequently reported on the
syzkaller dashboard.
Thus, check if we have an existing connection before generatin
binder: fix UAF of ref->proc caused by race condition
In the Linux kernel, the following vulnerability has been resolved:
binder: fix UAF of ref->proc caused by race condition
A transaction of type BINDER_TYPE_WEAK_HANDLE can fail to increment the
reference for a node. In this case, the target proc normally releases
the failed reference upon close as expected. However, if the target is
dying in parallel the call will race with binder_deferred_release(), so
the target could have released all of its references by now leaving the
cleanup of the new failed reference unhandled.
The transaction then ends and the target proc gets released making the
ref->proc now a dangling pointer. Later on, ref->n
media: mceusb: Use new usb_control_msg_*() routines
In the Linux kernel, the following vulnerability has been resolved:
media: mceusb: Use new usb_control_msg_*() routines
Automatic kernel fuzzing led to a WARN about invalid pipe direction in
the mceusb driver:
------------[ cut here ]------------
usb 6-1: BOGUS control dir, pipe 80000380 doesn't match bRequestType 40
WARNING: CPU: 0 PID: 2465 at drivers/usb/core/urb.c:410
usb_submit_urb+0x1326/0x1820 drivers/usb/core/urb.c:410
Modules linked in:
CPU: 0 PID: 2465 Comm: kworker/0:2 Not tainted 5.19.0-rc4-00208-g69cb6c6556ad #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
Workqueue: usb_hub_wq hub_e
In the Linux kernel, the following vulnerability has been resolved:
USB: core: Prevent nested device-reset calls
Automatic kernel fuzzing revealed a recursive locking violation in
usb-storage:
============================================
WARNING: possible recursive locking detected
5.18.0 #3 Not tainted
--------------------------------------------
kworker/1:3/1205 is trying to acquire lock:
ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at:
usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230
but task is already holding lock:
ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at:
usb_stor_pre_reset+0x35/0x40 drivers/usb/stor
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: Fix UAF in ieee80211_scan_rx()
ieee80211_scan_rx() tries to access scan_req->flags after a
null check, but a UAF is observed when the scan is completed
and __ieee80211_scan_completed() executes, which then calls
cfg80211_scan_done() leading to the freeing of scan_req.
Since scan_req is rcu_dereference()'d, prevent the racing in
__ieee80211_scan_completed() by ensuring that from mac80211's
POV it is no longer accessed from an RCU read critical section
before we call cfg80211_scan_done().
In the Linux kernel, the following vulnerability has been resolved:
IB/hfi1: Correctly move list in sc_disable()
Commit 13bac861952a ("IB/hfi1: Fix abba locking issue with sc_disable()")
incorrectly tries to move a list from one list head to another. The
result is a kernel crash.
The crash is triggered when a link goes down and there are waiters for a
send to complete. The following signature is seen:
BUG: kernel NULL pointer dereference, address: 0000000000000030
[...]
Call Trace:
sc_disable+0x1ba/0x240 [hfi1]
pio_freeze+0x3d/0x60 [hfi1]
handle_freeze+0x27/0x1b0 [hfi1]
process_one_work+0x1b0/0x380
? process_one_wor