In the Linux kernel, the following vulnerability has been resolved:
selinux: fix memleak in security_read_state_kernel()
In this function, it directly returns the result of __security_read_policy
without freeing the allocated memory in *data, cause memory leak issue,
so free the memory if __security_read_policy failed.
[PM: subject line tweak]
In the Linux kernel, the following vulnerability has been resolved:
PM: hibernate: defer device probing when resuming from hibernation
syzbot is reporting hung task at misc_open() [1], for there is a race
window of AB-BA deadlock which involves probe_count variable. Currently
wait_for_device_probe() from snapshot_open() from misc_open() can sleep
forever with misc_mtx held if probe_count cannot become 0.
When a device is probed by hub_event() work function, probe_count is
incremented before the probe function starts, and probe_count is
decremented after the probe function completed.
There are three cases that can prevent probe_count from dropping to 0.
(a) A device being probed stopped responding (i.e. broken/malicious
hardware).
(b) A process emulating a USB device using /dev/raw-gadget interface
stopped responding for some reason.
(c) New device probe requests keeps coming in before existing device
probe requests complete.
The phenomenon syzbot is reporting is (b). A process which is holding
system_transition_mutex and misc_mtx is waiting for probe_count to become
0 inside wait_for_device_probe(), but the probe function which is called
from hub_event() work function is waiting for the processes which are
blocked at mutex_lock(&misc_mtx) to respond via /dev/raw-gadget interface.
This patch mitigates (b) by deferring wait_for_device_probe() from
snapshot_open() to snapshot_write() and snapshot_ioctl(). Please note that
the possibility of (b) remains as long as any thread which is emulating a
USB device via /dev/raw-gadget interface can be blocked by uninterruptible
blocking operations (e.g. mutex_lock()).
Please also note that (a) and (c) are not addressed. Regarding (c), we
should change the code to wait for only one device which contains the
image for resuming from hibernation. I don't know how to address (a), for
use of timeout for wait_for_device_probe() might result in loss of user
data in the image. Maybe we should require the userland to wait for the
image device before opening /dev/snapshot interface.
In the Linux kernel, the following vulnerability has been resolved:
drm/radeon: fix potential buffer overflow in ni_set_mc_special_registers()
The last case label can write two buffers 'mc_reg_address[j]' and
'mc_data[j]' with 'j' offset equal to SMC_NISLANDS_MC_REGISTER_ARRAY_SIZE
since there are no checks for this value in both case labels after the
last 'j++'.
Instead of changing '>' to '>=' there, add the bounds check at the start
of the second 'case' (the first one already has it).
Also, remove redundant last checks for 'j' index bigger than array size.
The expression is always false. Moreover, before or after the patch
'table->last' can be equal to SMC_NISLANDS_MC_REGISTER_ARRAY_SIZE and it
seems it can be a valid value.
Detected using the static analysis tool - Svace.
In the Linux kernel, the following vulnerability has been resolved:
ath11k: fix netdev open race
Make sure to allocate resources needed before registering the device.
This specifically avoids having a racing open() trigger a BUG_ON() in
mod_timer() when ath11k_mac_op_start() is called before the
mon_reap_timer as been set up.
I did not see this issue with next-20220310, but I hit it on every probe
with next-20220511. Perhaps some timing changed in between.
Here's the backtrace:
[ 51.346947] kernel BUG at kernel/time/timer.c:990!
[ 51.346958] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
...
[ 51.578225] Call trace:
[ 51.583293] __mod_timer+0x298/0x390
[ 51.589518] mod_timer+0x14/0x20
[ 51.595368] ath11k_mac_op_start+0x41c/0x4a0 [ath11k]
[ 51.603165] drv_start+0x38/0x60 [mac80211]
[ 51.610110] ieee80211_do_open+0x29c/0x7d0 [mac80211]
[ 51.617945] ieee80211_open+0x60/0xb0 [mac80211]
[ 51.625311] __dev_open+0x100/0x1c0
[ 51.631420] __dev_change_flags+0x194/0x210
[ 51.638214] dev_change_flags+0x24/0x70
[ 51.644646] do_setlink+0x228/0xdb0
[ 51.650723] __rtnl_newlink+0x460/0x830
[ 51.657162] rtnl_newlink+0x4c/0x80
[ 51.663229] rtnetlink_rcv_msg+0x124/0x390
[ 51.669917] netlink_rcv_skb+0x58/0x130
[ 51.676314] rtnetlink_rcv+0x18/0x30
[ 51.682460] netlink_unicast+0x250/0x310
[ 51.688960] netlink_sendmsg+0x19c/0x3e0
[ 51.695458] ____sys_sendmsg+0x220/0x290
[ 51.701938] ___sys_sendmsg+0x7c/0xc0
[ 51.708148] __sys_sendmsg+0x68/0xd0
[ 51.714254] __arm64_sys_sendmsg+0x28/0x40
[ 51.720900] invoke_syscall+0x48/0x120
Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3
In the Linux kernel, the following vulnerability has been resolved:
spi: Fix simplification of devm_spi_register_controller
This reverts commit 59ebbe40fb51 ("spi: simplify
devm_spi_register_controller").
If devm_add_action() fails in devm_add_action_or_reset(),
devm_spi_unregister() will be called, it decreases the
refcount of 'ctlr->dev' to 0, then it will cause uaf in
the drivers that calling spi_put_controller() in error path.
In the Linux kernel, the following vulnerability has been resolved:
regulator: of: Fix refcount leak bug in of_get_regulation_constraints()
We should call the of_node_put() for the reference returned by
of_get_child_by_name() which has increased the refcount.
In the Linux kernel, the following vulnerability has been resolved:
rcutorture: Fix ksoftirqd boosting timing and iteration
The RCU priority boosting can fail in two situations:
1) If (nr_cpus= > maxcpus=), which means if the total number of CPUs
is higher than those brought online at boot, then torture_onoff() may
later bring up CPUs that weren't online on boot. Now since rcutorture
initialization only boosts the ksoftirqds of the CPUs that have been
set online on boot, the CPUs later set online by torture_onoff won't
benefit from the boost, making RCU priority boosting fail.
2) The ksoftirqd kthreads are boosted after the creation of
rcu_torture_boost() kthreads, which opens a window large enough for these
rcu_torture_boost() kthreads to wait (despite running at FIFO priority)
for ksoftirqds that are still running at SCHED_NORMAL priority.
The issues can trigger for example with:
./kvm.sh --configs TREE01 --kconfig "CONFIG_RCU_BOOST=y"
[ 34.968561] rcu-torture: !!!
[ 34.968627] ------------[ cut here ]------------
[ 35.014054] WARNING: CPU: 4 PID: 114 at kernel/rcu/rcutorture.c:1979 rcu_torture_stats_print+0x5ad/0x610
[ 35.052043] Modules linked in:
[ 35.069138] CPU: 4 PID: 114 Comm: rcu_torture_sta Not tainted 5.18.0-rc1 #1
[ 35.096424] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
[ 35.154570] RIP: 0010:rcu_torture_stats_print+0x5ad/0x610
[ 35.198527] Code: 63 1b 02 00 74 02 0f 0b 48 83 3d 35 63 1b 02 00 74 02 0f 0b 48 83 3d 21 63 1b 02 00 74 02 0f 0b 48 83 3d 0d 63 1b 02 00 74 02 <0f> 0b 83 eb 01 0f 8e ba fc ff ff 0f 0b e9 b3 fc ff f82
[ 37.251049] RSP: 0000:ffffa92a0050bdf8 EFLAGS: 00010202
[ 37.277320] rcu: De-offloading 8
[ 37.290367] RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001
[ 37.290387] RDX: 0000000000000000 RSI: 00000000ffffbfff RDI: 00000000ffffffff
[ 37.290398] RBP: 000000000000007b R08: 0000000000000000 R09: c0000000ffffbfff
[ 37.290407] R10: 000000000000002a R11: ffffa92a0050bc18 R12: ffffa92a0050be20
[ 37.290417] R13: ffffa92a0050be78 R14: 0000000000000000 R15: 000000000001bea0
[ 37.290427] FS: 0000000000000000(0000) GS:ffff96045eb00000(0000) knlGS:0000000000000000
[ 37.290448] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 37.290460] CR2: 0000000000000000 CR3: 000000001dc0c000 CR4: 00000000000006e0
[ 37.290470] Call Trace:
[ 37.295049] <TASK>
[ 37.295065] ? preempt_count_add+0x63/0x90
[ 37.295095] ? _raw_spin_lock_irqsave+0x12/0x40
[ 37.295125] ? rcu_torture_stats_print+0x610/0x610
[ 37.295143] rcu_torture_stats+0x29/0x70
[ 37.295160] kthread+0xe3/0x110
[ 37.295176] ? kthread_complete_and_exit+0x20/0x20
[ 37.295193] ret_from_fork+0x22/0x30
[ 37.295218] </TASK>
Fix this with boosting the ksoftirqds kthreads from the boosting
hotplug callback itself and before the boosting kthreads are created.
In the Linux kernel, the following vulnerability has been resolved:
ath9k: fix use-after-free in ath9k_hif_usb_rx_cb
Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb() [0]. The
problem was in incorrect htc_handle->drv_priv initialization.
Probable call trace which can trigger use-after-free:
ath9k_htc_probe_device()
/* htc_handle->drv_priv = priv; */
ath9k_htc_wait_for_target() <--- Failed
ieee80211_free_hw() <--- priv pointer is freed
<IRQ>
...
ath9k_hif_usb_rx_cb()
ath9k_hif_usb_rx_stream()
RX_STAT_INC() <--- htc_handle->drv_priv access
In order to not add fancy protection for drv_priv we can move
htc_handle->drv_priv initialization at the end of the
ath9k_htc_probe_device() and add helper macro to make
all *_STAT_* macros NULL safe, since syzbot has reported related NULL
deref in that macros [1]
In the Linux kernel, the following vulnerability has been resolved:
virtio-gpu: fix a missing check to avoid NULL dereference
'cache_ent' could be set NULL inside virtio_gpu_cmd_get_capset()
and it will lead to a NULL dereference by a lately use of it
(i.e., ptr = cache_ent->caps_cache). Fix it with a NULL check.
[ kraxel: minor codestyle fixup ]
In the Linux kernel, the following vulnerability has been resolved:
media: imx-jpeg: Align upwards buffer size
The hardware can support any image size WxH,
with arbitrary W (image width) and H (image height) dimensions.
Align upwards buffer size for both encoder and decoder.
and leave the picture resolution unchanged.
For decoder, the risk of memory out of bounds can be avoided.
For both encoder and decoder, the driver will lift the limitation of
resolution alignment.
For example, the decoder can support jpeg whose resolution is 227x149
the encoder can support nv12 1080P, won't change it to 1920x1072.