| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
backlight: led-bl: Add devlink to supplier LEDs
LED Backlight is a consumer of one or multiple LED class devices, but
devlink is currently unable to create correct supplier-producer links when
the supplier is a class device. It creates instead a link where the
supplier is the parent of the expected device.
One consequence is that removal order is not correctly enforced.
Issues happen for example with the following sections in a device tree
overlay:
// An LED driver chip
pca9632@62 {
compatible = "nxp,pca9632";
reg = <0x62>;
// ...
addon_led_pwm: led-pwm@3 {
reg = <3>;
label = "addon:led:pwm";
};
};
backlight-addon {
compatible = "led-backlight";
leds = <&addon_led_pwm>;
brightness-levels = <255>;
default-brightness-level = <255>;
};
In this example, the devlink should be created between the backlight-addon
(consumer) and the pca9632@62 (supplier). Instead it is created between the
backlight-addon (consumer) and the parent of the pca9632@62, which is
typically the I2C bus adapter.
On removal of the above overlay, the LED driver can be removed before the
backlight device, resulting in:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
...
Call trace:
led_put+0xe0/0x140
devm_led_release+0x6c/0x98
Another way to reproduce the bug without any device tree overlays is
unbinding the LED class device (pca9632@62) before unbinding the consumer
(backlight-addon):
echo 11-0062 >/sys/bus/i2c/drivers/leds-pca963x/unbind
echo ...backlight-dock >/sys/bus/platform/drivers/led-backlight/unbind
Fix by adding a devlink between the consuming led-backlight device and the
supplying LED device, as other drivers and subsystems do as well. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: rtl818x: Fix potential memory leaks in rtl8180_init_rx_ring()
In rtl8180_init_rx_ring(), memory is allocated for skb packets and DMA
allocations in a loop. When an allocation fails, the previously
successful allocations are not freed on exit.
Fix that by jumping to err_free_rings label on error, which calls
rtl8180_free_rx_ring() to free the allocations. Remove the free of
rx_ring in rtl8180_init_rx_ring() error path, and set the freed
priv->rx_buf entry to null, to avoid double free. |
| In the Linux kernel, the following vulnerability has been resolved:
rtc: amlogic-a4: fix double free caused by devm
The clock obtained via devm_clk_get_enabled() is automatically managed
by devres and will be disabled and freed on driver detach. Manually
calling clk_disable_unprepare() in error path and remove function
causes double free.
Remove the redundant clk_disable_unprepare() calls from the probe
error path and aml_rtc_remove(), allowing the devm framework to
automatically manage the clock lifecycle. |
| In the Linux kernel, the following vulnerability has been resolved:
iavf: Implement settime64 with -EOPNOTSUPP
ptp_clock_settime() assumes every ptp_clock has implemented settime64().
Stub it with -EOPNOTSUPP to prevent a NULL dereference.
The fix is similar to commit 329d050bbe63 ("gve: Implement settime64
with -EOPNOTSUPP"). |
| In the Linux kernel, the following vulnerability has been resolved:
s390/fpu: Fix false-positive kmsan report in fpu_vstl()
A false-positive kmsan report is detected when running ping command.
An inline assembly instruction 'vstl' can write varied amount of bytes
depending on value of 'index' argument. If 'index' > 0, 'vstl' writes
at least 2 bytes.
clang generates kmsan write helper call depending on inline assembly
constraints. Constraints are evaluated compile-time, but value of
'index' argument is known only at runtime.
clang currently generates call to __msan_instrument_asm_store with 1 byte
as size. Manually call kmsan function to indicate correct amount of bytes
written and fix false-positive report.
This change fixes following kmsan reports:
[ 36.563119] =====================================================
[ 36.563594] BUG: KMSAN: uninit-value in virtqueue_add+0x35c6/0x7c70
[ 36.563852] virtqueue_add+0x35c6/0x7c70
[ 36.564016] virtqueue_add_outbuf+0xa0/0xb0
[ 36.564266] start_xmit+0x288c/0x4a20
[ 36.564460] dev_hard_start_xmit+0x302/0x900
[ 36.564649] sch_direct_xmit+0x340/0xea0
[ 36.564894] __dev_queue_xmit+0x2e94/0x59b0
[ 36.565058] neigh_resolve_output+0x936/0xb40
[ 36.565278] __neigh_update+0x2f66/0x3a60
[ 36.565499] neigh_update+0x52/0x60
[ 36.565683] arp_process+0x1588/0x2de0
[ 36.565916] NF_HOOK+0x1da/0x240
[ 36.566087] arp_rcv+0x3e4/0x6e0
[ 36.566306] __netif_receive_skb_list_core+0x1374/0x15a0
[ 36.566527] netif_receive_skb_list_internal+0x1116/0x17d0
[ 36.566710] napi_complete_done+0x376/0x740
[ 36.566918] virtnet_poll+0x1bae/0x2910
[ 36.567130] __napi_poll+0xf4/0x830
[ 36.567294] net_rx_action+0x97c/0x1ed0
[ 36.567556] handle_softirqs+0x306/0xe10
[ 36.567731] irq_exit_rcu+0x14c/0x2e0
[ 36.567910] do_io_irq+0xd4/0x120
[ 36.568139] io_int_handler+0xc2/0xe8
[ 36.568299] arch_cpu_idle+0xb0/0xc0
[ 36.568540] arch_cpu_idle+0x76/0xc0
[ 36.568726] default_idle_call+0x40/0x70
[ 36.568953] do_idle+0x1d6/0x390
[ 36.569486] cpu_startup_entry+0x9a/0xb0
[ 36.569745] rest_init+0x1ea/0x290
[ 36.570029] start_kernel+0x95e/0xb90
[ 36.570348] startup_continue+0x2e/0x40
[ 36.570703]
[ 36.570798] Uninit was created at:
[ 36.571002] kmem_cache_alloc_node_noprof+0x9e8/0x10e0
[ 36.571261] kmalloc_reserve+0x12a/0x470
[ 36.571553] __alloc_skb+0x310/0x860
[ 36.571844] __ip_append_data+0x483e/0x6a30
[ 36.572170] ip_append_data+0x11c/0x1e0
[ 36.572477] raw_sendmsg+0x1c8c/0x2180
[ 36.572818] inet_sendmsg+0xe6/0x190
[ 36.573142] __sys_sendto+0x55e/0x8e0
[ 36.573392] __s390x_sys_socketcall+0x19ae/0x2ba0
[ 36.573571] __do_syscall+0x12e/0x240
[ 36.573823] system_call+0x6e/0x90
[ 36.573976]
[ 36.574017] Byte 35 of 98 is uninitialized
[ 36.574082] Memory access of size 98 starts at 0000000007aa0012
[ 36.574218]
[ 36.574325] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G B N 6.17.0-dirty #16 NONE
[ 36.574541] Tainted: [B]=BAD_PAGE, [N]=TEST
[ 36.574617] Hardware name: IBM 3931 A01 703 (KVM/Linux)
[ 36.574755] =====================================================
[ 63.532541] =====================================================
[ 63.533639] BUG: KMSAN: uninit-value in virtqueue_add+0x35c6/0x7c70
[ 63.533989] virtqueue_add+0x35c6/0x7c70
[ 63.534940] virtqueue_add_outbuf+0xa0/0xb0
[ 63.535861] start_xmit+0x288c/0x4a20
[ 63.536708] dev_hard_start_xmit+0x302/0x900
[ 63.537020] sch_direct_xmit+0x340/0xea0
[ 63.537997] __dev_queue_xmit+0x2e94/0x59b0
[ 63.538819] neigh_resolve_output+0x936/0xb40
[ 63.539793] ip_finish_output2+0x1ee2/0x2200
[ 63.540784] __ip_finish_output+0x272/0x7a0
[ 63.541765] ip_finish_output+0x4e/0x5e0
[ 63.542791] ip_output+0x166/0x410
[ 63.543771] ip_push_pending_frames+0x1a2/0x470
[ 63.544753] raw_sendmsg+0x1f06/0x2180
[ 63.545033] inet_sendmsg+0xe6/0x190
[ 63.546006] __sys_sendto+0x55e/0x8e0
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
mshv: Fix create memory region overlap check
The current check is incorrect; it only checks if the beginning or end
of a region is within an existing region. This doesn't account for
userspace specifying a region that begins before and ends after an
existing region.
Change the logic to a range intersection check against gfns and uaddrs
for each region.
Remove mshv_partition_region_by_uaddr() as it is no longer used. |
| In the Linux kernel, the following vulnerability has been resolved:
PM / devfreq: hisi: Fix potential UAF in OPP handling
Ensure all required data is acquired before calling dev_pm_opp_put(opp)
to maintain correct resource acquisition and release order. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7996: fix null pointer deref in mt7996_conf_tx()
If a link does not have an assigned channel yet, mt7996_vif_link returns
NULL. We still need to store the updated queue settings in that case, and
apply them later.
Move the location of the queue params to within struct mt7996_vif_link. |
| In the Linux kernel, the following vulnerability has been resolved:
smack: fix bug: unprivileged task can create labels
If an unprivileged task is allowed to relabel itself
(/smack/relabel-self is not empty),
it can freely create new labels by writing their
names into own /proc/PID/attr/smack/current
This occurs because do_setattr() imports
the provided label in advance,
before checking "relabel-self" list.
This change ensures that the "relabel-self" list
is checked before importing the label. |
| In the Linux kernel, the following vulnerability has been resolved:
gpu: host1x: Fix race in syncpt alloc/free
Fix race condition between host1x_syncpt_alloc()
and host1x_syncpt_put() by using kref_put_mutex()
instead of kref_put() + manual mutex locking.
This ensures no thread can acquire the
syncpt_mutex after the refcount drops to zero
but before syncpt_release acquires it.
This prevents races where syncpoints could
be allocated while still being cleaned up
from a previous release.
Remove explicit mutex locking in syncpt_release
as kref_put_mutex() handles this atomically. |
| In the Linux kernel, the following vulnerability has been resolved:
accel/amdxdna: Fix an integer overflow in aie2_query_ctx_status_array()
The unpublished smatch static checker reported a warning.
drivers/accel/amdxdna/aie2_pci.c:904 aie2_query_ctx_status_array()
warn: potential user controlled sizeof overflow
'args->num_element * args->element_size' '1-u32max(user) * 1-u32max(user)'
Even this will not cause a real issue, it is better to put a reasonable
limitation for element_size and num_element. Add condition to make sure
the input element_size <= 4K and num_element <= 1K. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/vgem-fence: Fix potential deadlock on release
A timer that expires a vgem fence automatically in 10 seconds is now
released with timer_delete_sync() from fence->ops.release() called on last
dma_fence_put(). In some scenarios, it can run in IRQ context, which is
not safe unless TIMER_IRQSAFE is used. One potentially risky scenario was
demonstrated in Intel DRM CI trybot, BAT run on machine bat-adlp-6, while
working on new IGT subtests syncobj_timeline@stress-* as user space
replacements of some problematic test cases of a dma-fence-chain selftest
[1].
[117.004338] ================================
[117.004340] WARNING: inconsistent lock state
[117.004342] 6.17.0-rc7-CI_DRM_17270-g7644974e648c+ #1 Tainted: G S U
[117.004346] --------------------------------
[117.004347] inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
[117.004349] swapper/0/0 [HC1[1]:SC1[1]:HE0:SE0] takes:
[117.004352] ffff888138f86aa8 ((&fence->timer)){?.-.}-{0:0}, at: __timer_delete_sync+0x4b/0x190
[117.004361] {HARDIRQ-ON-W} state was registered at:
[117.004363] lock_acquire+0xc4/0x2e0
[117.004366] call_timer_fn+0x80/0x2a0
[117.004368] __run_timers+0x231/0x310
[117.004370] run_timer_softirq+0x76/0xe0
[117.004372] handle_softirqs+0xd4/0x4d0
[117.004375] __irq_exit_rcu+0x13f/0x160
[117.004377] irq_exit_rcu+0xe/0x20
[117.004379] sysvec_apic_timer_interrupt+0xa0/0xc0
[117.004382] asm_sysvec_apic_timer_interrupt+0x1b/0x20
[117.004385] cpuidle_enter_state+0x12b/0x8a0
[117.004388] cpuidle_enter+0x2e/0x50
[117.004393] call_cpuidle+0x22/0x60
[117.004395] do_idle+0x1fd/0x260
[117.004398] cpu_startup_entry+0x29/0x30
[117.004401] start_secondary+0x12d/0x160
[117.004404] common_startup_64+0x13e/0x141
[117.004407] irq event stamp: 2282669
[117.004409] hardirqs last enabled at (2282668): [<ffffffff8289db71>] _raw_spin_unlock_irqrestore+0x51/0x80
[117.004414] hardirqs last disabled at (2282669): [<ffffffff82882021>] sysvec_irq_work+0x11/0xc0
[117.004419] softirqs last enabled at (2254702): [<ffffffff8289fd00>] __do_softirq+0x10/0x18
[117.004423] softirqs last disabled at (2254725): [<ffffffff813d4ddf>] __irq_exit_rcu+0x13f/0x160
[117.004426]
other info that might help us debug this:
[117.004429] Possible unsafe locking scenario:
[117.004432] CPU0
[117.004433] ----
[117.004434] lock((&fence->timer));
[117.004436] <Interrupt>
[117.004438] lock((&fence->timer));
[117.004440]
*** DEADLOCK ***
[117.004443] 1 lock held by swapper/0/0:
[117.004445] #0: ffffc90000003d50 ((&fence->timer)){?.-.}-{0:0}, at: call_timer_fn+0x7a/0x2a0
[117.004450]
stack backtrace:
[117.004453] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G S U 6.17.0-rc7-CI_DRM_17270-g7644974e648c+ #1 PREEMPT(voluntary)
[117.004455] Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER
[117.004455] Hardware name: Intel Corporation Alder Lake Client Platform/AlderLake-P DDR4 RVP, BIOS RPLPFWI1.R00.4035.A00.2301200723 01/20/2023
[117.004456] Call Trace:
[117.004456] <IRQ>
[117.004457] dump_stack_lvl+0x91/0xf0
[117.004460] dump_stack+0x10/0x20
[117.004461] print_usage_bug.part.0+0x260/0x360
[117.004463] mark_lock+0x76e/0x9c0
[117.004465] ? register_lock_class+0x48/0x4a0
[117.004467] __lock_acquire+0xbc3/0x2860
[117.004469] lock_acquire+0xc4/0x2e0
[117.004470] ? __timer_delete_sync+0x4b/0x190
[117.004472] ? __timer_delete_sync+0x4b/0x190
[117.004473] __timer_delete_sync+0x68/0x190
[117.004474] ? __timer_delete_sync+0x4b/0x190
[117.004475] timer_delete_sync+0x10/0x20
[117.004476] vgem_fence_release+0x19/0x30 [vgem]
[117.004478] dma_fence_release+0xc1/0x3b0
[117.004480] ? dma_fence_release+0xa1/0x3b0
[117.004481] dma_fence_chain_release+0xe7/0x130
[117.004483] dma_fence_release+0xc1/0x3b0
[117.004484] ? _raw_spin_unlock_irqrestore+0x27/0x80
[117.004485] dma_fence_chain_irq_work+0x59/0x80
[117.004487] irq_work_single+0x75/0xa0
[117.004490] irq_work_r
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
ntfs3: fix uninit memory after failed mi_read in mi_format_new
Fix a KMSAN un-init bug found by syzkaller.
ntfs_get_bh() expects a buffer from sb_getblk(), that buffer may not be
uptodate. We do not bring the buffer uptodate before setting it as
uptodate. If the buffer were to not be uptodate, it could mean adding a
buffer with un-init data to the mi record. Attempting to load that record
will trigger KMSAN.
Avoid this by setting the buffer as uptodate, if it’s not already, by
overwriting it. |
| In the Linux kernel, the following vulnerability has been resolved:
ntfs3: Fix uninit buffer allocated by __getname()
Fix uninit errors caused after buffer allocation given to 'de'; by
initializing the buffer with zeroes. The fix was found by using KMSAN. |
| In the Linux kernel, the following vulnerability has been resolved:
block: Use RCU in blk_mq_[un]quiesce_tagset() instead of set->tag_list_lock
blk_mq_{add,del}_queue_tag_set() functions add and remove queues from
tagset, the functions make sure that tagset and queues are marked as
shared when two or more queues are attached to the same tagset.
Initially a tagset starts as unshared and when the number of added
queues reaches two, blk_mq_add_queue_tag_set() marks it as shared along
with all the queues attached to it. When the number of attached queues
drops to 1 blk_mq_del_queue_tag_set() need to mark both the tagset and
the remaining queues as unshared.
Both functions need to freeze current queues in tagset before setting on
unsetting BLK_MQ_F_TAG_QUEUE_SHARED flag. While doing so, both functions
hold set->tag_list_lock mutex, which makes sense as we do not want
queues to be added or deleted in the process. This used to work fine
until commit 98d81f0df70c ("nvme: use blk_mq_[un]quiesce_tagset")
made the nvme driver quiesce tagset instead of quiscing individual
queues. blk_mq_quiesce_tagset() does the job and quiesce the queues in
set->tag_list while holding set->tag_list_lock also.
This results in deadlock between two threads with these stacktraces:
__schedule+0x47c/0xbb0
? timerqueue_add+0x66/0xb0
schedule+0x1c/0xa0
schedule_preempt_disabled+0xa/0x10
__mutex_lock.constprop.0+0x271/0x600
blk_mq_quiesce_tagset+0x25/0xc0
nvme_dev_disable+0x9c/0x250
nvme_timeout+0x1fc/0x520
blk_mq_handle_expired+0x5c/0x90
bt_iter+0x7e/0x90
blk_mq_queue_tag_busy_iter+0x27e/0x550
? __blk_mq_complete_request_remote+0x10/0x10
? __blk_mq_complete_request_remote+0x10/0x10
? __call_rcu_common.constprop.0+0x1c0/0x210
blk_mq_timeout_work+0x12d/0x170
process_one_work+0x12e/0x2d0
worker_thread+0x288/0x3a0
? rescuer_thread+0x480/0x480
kthread+0xb8/0xe0
? kthread_park+0x80/0x80
ret_from_fork+0x2d/0x50
? kthread_park+0x80/0x80
ret_from_fork_asm+0x11/0x20
__schedule+0x47c/0xbb0
? xas_find+0x161/0x1a0
schedule+0x1c/0xa0
blk_mq_freeze_queue_wait+0x3d/0x70
? destroy_sched_domains_rcu+0x30/0x30
blk_mq_update_tag_set_shared+0x44/0x80
blk_mq_exit_queue+0x141/0x150
del_gendisk+0x25a/0x2d0
nvme_ns_remove+0xc9/0x170
nvme_remove_namespaces+0xc7/0x100
nvme_remove+0x62/0x150
pci_device_remove+0x23/0x60
device_release_driver_internal+0x159/0x200
unbind_store+0x99/0xa0
kernfs_fop_write_iter+0x112/0x1e0
vfs_write+0x2b1/0x3d0
ksys_write+0x4e/0xb0
do_syscall_64+0x5b/0x160
entry_SYSCALL_64_after_hwframe+0x4b/0x53
The top stacktrace is showing nvme_timeout() called to handle nvme
command timeout. timeout handler is trying to disable the controller and
as a first step, it needs to blk_mq_quiesce_tagset() to tell blk-mq not
to call queue callback handlers. The thread is stuck waiting for
set->tag_list_lock as it tries to walk the queues in set->tag_list.
The lock is held by the second thread in the bottom stack which is
waiting for one of queues to be frozen. The queue usage counter will
drop to zero after nvme_timeout() finishes, and this will not happen
because the thread will wait for this mutex forever.
Given that [un]quiescing queue is an operation that does not need to
sleep, update blk_mq_[un]quiesce_tagset() to use RCU instead of taking
set->tag_list_lock, update blk_mq_{add,del}_queue_tag_set() to use RCU
safe list operations. Also, delete INIT_LIST_HEAD(&q->tag_set_list)
in blk_mq_del_queue_tag_set() because we can not re-initialize it while
the list is being traversed under RCU. The deleted queue will not be
added/deleted to/from a tagset and it will be freed in blk_free_queue()
after the end of RCU grace period. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: fix peer HE MCS assignment
In ath11k_wmi_send_peer_assoc_cmd(), peer's transmit MCS is sent to
firmware as receive MCS while peer's receive MCS sent as transmit MCS,
which goes against firmwire's definition.
While connecting to a misbehaved AP that advertises 0xffff (meaning not
supported) for 160 MHz transmit MCS map, firmware crashes due to 0xffff
is assigned to he_mcs->rx_mcs_set field.
Ext Tag: HE Capabilities
[...]
Supported HE-MCS and NSS Set
[...]
Rx and Tx MCS Maps 160 MHz
[...]
Tx HE-MCS Map 160 MHz: 0xffff
Swap the assignment to fix this issue.
As the HE rate control mask is meant to limit our own transmit MCS, it
needs to go via he_mcs->rx_mcs_set field. With the aforementioned swapping
done, change is needed as well to apply it to the peer's receive MCS.
Tested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1 |
| In the Linux kernel, the following vulnerability has been resolved:
perf/x86: Fix NULL event access and potential PEBS record loss
When intel_pmu_drain_pebs_icl() is called to drain PEBS records, the
perf_event_overflow() could be called to process the last PEBS record.
While perf_event_overflow() could trigger the interrupt throttle and
stop all events of the group, like what the below call-chain shows.
perf_event_overflow()
-> __perf_event_overflow()
->__perf_event_account_interrupt()
-> perf_event_throttle_group()
-> perf_event_throttle()
-> event->pmu->stop()
-> x86_pmu_stop()
The side effect of stopping the events is that all corresponding event
pointers in cpuc->events[] array are cleared to NULL.
Assume there are two PEBS events (event a and event b) in a group. When
intel_pmu_drain_pebs_icl() calls perf_event_overflow() to process the
last PEBS record of PEBS event a, interrupt throttle is triggered and
all pointers of event a and event b are cleared to NULL. Then
intel_pmu_drain_pebs_icl() tries to process the last PEBS record of
event b and encounters NULL pointer access.
To avoid this issue, move cpuc->events[] clearing from x86_pmu_stop()
to x86_pmu_del(). It's safe since cpuc->active_mask or
cpuc->pebs_enabled is always checked before access the event pointer
from cpuc->events[]. |
| In the Linux kernel, the following vulnerability has been resolved:
md: avoid repeated calls to del_gendisk
There is a uaf problem which is found by case 23rdev-lifetime:
Oops: general protection fault, probably for non-canonical address 0xdead000000000122
RIP: 0010:bdi_unregister+0x4b/0x170
Call Trace:
<TASK>
__del_gendisk+0x356/0x3e0
mddev_unlock+0x351/0x360
rdev_attr_store+0x217/0x280
kernfs_fop_write_iter+0x14a/0x210
vfs_write+0x29e/0x550
ksys_write+0x74/0xf0
do_syscall_64+0xbb/0x380
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff5250a177e
The sequence is:
1. rdev remove path gets reconfig_mutex
2. rdev remove path release reconfig_mutex in mddev_unlock
3. md stop calls do_md_stop and sets MD_DELETED
4. rdev remove path calls del_gendisk because MD_DELETED is set
5. md stop path release reconfig_mutex and calls del_gendisk again
So there is a race condition we should resolve. This patch adds a
flag MD_DO_DELETE to avoid the race condition. |
| In the Linux kernel, the following vulnerability has been resolved:
macintosh/mac_hid: fix race condition in mac_hid_toggle_emumouse
The following warning appears when running syzkaller, and this issue also
exists in the mainline code.
------------[ cut here ]------------
list_add double add: new=ffffffffa57eee28, prev=ffffffffa57eee28, next=ffffffffa5e63100.
WARNING: CPU: 0 PID: 1491 at lib/list_debug.c:35 __list_add_valid_or_report+0xf7/0x130
Modules linked in:
CPU: 0 PID: 1491 Comm: syz.1.28 Not tainted 6.6.0+ #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:__list_add_valid_or_report+0xf7/0x130
RSP: 0018:ff1100010dfb7b78 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffffffa57eee18 RCX: ffffffff97fc9817
RDX: 0000000000040000 RSI: ffa0000002383000 RDI: 0000000000000001
RBP: ffffffffa57eee28 R08: 0000000000000001 R09: ffe21c0021bf6f2c
R10: 0000000000000001 R11: 6464615f7473696c R12: ffffffffa5e63100
R13: ffffffffa57eee28 R14: ffffffffa57eee28 R15: ff1100010dfb7d48
FS: 00007fb14398b640(0000) GS:ff11000119600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000010d096005 CR4: 0000000000773ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 80000000
Call Trace:
<TASK>
input_register_handler+0xb3/0x210
mac_hid_start_emulation+0x1c5/0x290
mac_hid_toggle_emumouse+0x20a/0x240
proc_sys_call_handler+0x4c2/0x6e0
new_sync_write+0x1b1/0x2d0
vfs_write+0x709/0x950
ksys_write+0x12a/0x250
do_syscall_64+0x5a/0x110
entry_SYSCALL_64_after_hwframe+0x78/0xe2
The WARNING occurs when two processes concurrently write to the mac-hid
emulation sysctl, causing a race condition in mac_hid_toggle_emumouse().
Both processes read old_val=0, then both try to register the input handler,
leading to a double list_add of the same handler.
CPU0 CPU1
------------------------- -------------------------
vfs_write() //write 1 vfs_write() //write 1
proc_sys_write() proc_sys_write()
mac_hid_toggle_emumouse() mac_hid_toggle_emumouse()
old_val = *valp // old_val=0
old_val = *valp // old_val=0
mutex_lock_killable()
proc_dointvec() // *valp=1
mac_hid_start_emulation()
input_register_handler()
mutex_unlock()
mutex_lock_killable()
proc_dointvec()
mac_hid_start_emulation()
input_register_handler() //Trigger Warning
mutex_unlock()
Fix this by moving the old_val read inside the mutex lock region. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: relax BUG() to ocfs2_error() in __ocfs2_move_extent()
In '__ocfs2_move_extent()', relax 'BUG()' to 'ocfs2_error()' just
to avoid crashing the whole kernel due to a filesystem corruption. |