| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/irdma: Fix data race on CQP completion stats
CQP completion statistics is read lockesly in irdma_wait_event and
irdma_check_cqp_progress while it can be updated in the completion
thread irdma_sc_ccq_get_cqe_info on another CPU as KCSAN reports.
Make completion statistics an atomic variable to reflect coherent updates
to it. This will also avoid load/store tearing logic bug potentially
possible by compiler optimizations.
[77346.170861] BUG: KCSAN: data-race in irdma_handle_cqp_op [irdma] / irdma_sc_ccq_get_cqe_info [irdma]
[77346.171383] write to 0xffff8a3250b108e0 of 8 bytes by task 9544 on cpu 4:
[77346.171483] irdma_sc_ccq_get_cqe_info+0x27a/0x370 [irdma]
[77346.171658] irdma_cqp_ce_handler+0x164/0x270 [irdma]
[77346.171835] cqp_compl_worker+0x1b/0x20 [irdma]
[77346.172009] process_one_work+0x4d1/0xa40
[77346.172024] worker_thread+0x319/0x700
[77346.172037] kthread+0x180/0x1b0
[77346.172054] ret_from_fork+0x22/0x30
[77346.172136] read to 0xffff8a3250b108e0 of 8 bytes by task 9838 on cpu 2:
[77346.172234] irdma_handle_cqp_op+0xf4/0x4b0 [irdma]
[77346.172413] irdma_cqp_aeq_cmd+0x75/0xa0 [irdma]
[77346.172592] irdma_create_aeq+0x390/0x45a [irdma]
[77346.172769] irdma_rt_init_hw.cold+0x212/0x85d [irdma]
[77346.172944] irdma_probe+0x54f/0x620 [irdma]
[77346.173122] auxiliary_bus_probe+0x66/0xa0
[77346.173137] really_probe+0x140/0x540
[77346.173154] __driver_probe_device+0xc7/0x220
[77346.173173] driver_probe_device+0x5f/0x140
[77346.173190] __driver_attach+0xf0/0x2c0
[77346.173208] bus_for_each_dev+0xa8/0xf0
[77346.173225] driver_attach+0x29/0x30
[77346.173240] bus_add_driver+0x29c/0x2f0
[77346.173255] driver_register+0x10f/0x1a0
[77346.173272] __auxiliary_driver_register+0xbc/0x140
[77346.173287] irdma_init_module+0x55/0x1000 [irdma]
[77346.173460] do_one_initcall+0x7d/0x410
[77346.173475] do_init_module+0x81/0x2c0
[77346.173491] load_module+0x1232/0x12c0
[77346.173506] __do_sys_finit_module+0x101/0x180
[77346.173522] __x64_sys_finit_module+0x3c/0x50
[77346.173538] do_syscall_64+0x39/0x90
[77346.173553] entry_SYSCALL_64_after_hwframe+0x63/0xcd
[77346.173634] value changed: 0x0000000000000094 -> 0x0000000000000095 |
| In the Linux kernel, the following vulnerability has been resolved:
refscale: Fix uninitalized use of wait_queue_head_t
Running the refscale test occasionally crashes the kernel with the
following error:
[ 8569.952896] BUG: unable to handle page fault for address: ffffffffffffffe8
[ 8569.952900] #PF: supervisor read access in kernel mode
[ 8569.952902] #PF: error_code(0x0000) - not-present page
[ 8569.952904] PGD c4b048067 P4D c4b049067 PUD c4b04b067 PMD 0
[ 8569.952910] Oops: 0000 [#1] PREEMPT_RT SMP NOPTI
[ 8569.952916] Hardware name: Dell Inc. PowerEdge R750/0WMWCR, BIOS 1.2.4 05/28/2021
[ 8569.952917] RIP: 0010:prepare_to_wait_event+0x101/0x190
:
[ 8569.952940] Call Trace:
[ 8569.952941] <TASK>
[ 8569.952944] ref_scale_reader+0x380/0x4a0 [refscale]
[ 8569.952959] kthread+0x10e/0x130
[ 8569.952966] ret_from_fork+0x1f/0x30
[ 8569.952973] </TASK>
The likely cause is that init_waitqueue_head() is called after the call to
the torture_create_kthread() function that creates the ref_scale_reader
kthread. Although this init_waitqueue_head() call will very likely
complete before this kthread is created and starts running, it is
possible that the calling kthread will be delayed between the calls to
torture_create_kthread() and init_waitqueue_head(). In this case, the
new kthread will use the waitqueue head before it is properly initialized,
which is not good for the kernel's health and well-being.
The above crash happened here:
static inline void __add_wait_queue(...)
{
:
if (!(wq->flags & WQ_FLAG_PRIORITY)) <=== Crash here
The offset of flags from list_head entry in wait_queue_entry is
-0x18. If reader_tasks[i].wq.head.next is NULL as allocated reader_task
structure is zero initialized, the instruction will try to access address
0xffffffffffffffe8, which is exactly the fault address listed above.
This commit therefore invokes init_waitqueue_head() before creating
the kthread. |
| In the Linux kernel, the following vulnerability has been resolved:
netpoll: Fix deadlock in memory allocation under spinlock
Fix a AA deadlock in refill_skbs() where memory allocation while holding
skb_pool->lock can trigger a recursive lock acquisition attempt.
The deadlock scenario occurs when the system is under severe memory
pressure:
1. refill_skbs() acquires skb_pool->lock (spinlock)
2. alloc_skb() is called while holding the lock
3. Memory allocator fails and calls slab_out_of_memory()
4. This triggers printk() for the OOM warning
5. The console output path calls netpoll_send_udp()
6. netpoll_send_udp() attempts to acquire the same skb_pool->lock
7. Deadlock: the lock is already held by the same CPU
Call stack:
refill_skbs()
spin_lock_irqsave(&skb_pool->lock) <- lock acquired
__alloc_skb()
kmem_cache_alloc_node_noprof()
slab_out_of_memory()
printk()
console_flush_all()
netpoll_send_udp()
skb_dequeue()
spin_lock_irqsave(&skb_pool->lock) <- deadlock attempt
This bug was exposed by commit 248f6571fd4c51 ("netpoll: Optimize skb
refilling on critical path") which removed refill_skbs() from the
critical path (where nested printk was being deferred), letting nested
printk being called from inside refill_skbs()
Refactor refill_skbs() to never allocate memory while holding
the spinlock.
Another possible solution to fix this problem is protecting the
refill_skbs() from nested printks, basically calling
printk_deferred_{enter,exit}() in refill_skbs(), then, any nested
pr_warn() would be deferred.
I prefer this approach, given I _think_ it might be a good idea to move
the alloc_skb() from GFP_ATOMIC to GFP_KERNEL in the future, so, having
the alloc_skb() outside of the lock will be necessary step.
There is a possible TOCTOU issue when checking for the pool length, and
queueing the new allocated skb, but, this is not an issue, given that
an extra SKB in the pool is harmless and it will be eventually used. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/radeon: Remove calls to drm_put_dev()
Since the allocation of the drivers main structure was changed to
devm_drm_dev_alloc() drm_put_dev()'ing to trigger it to be free'd
should be done by devres.
However, drm_put_dev() is still in the probe error and device remove
paths. When the driver fails to probe warnings like the following are
shown because devres is trying to drm_put_dev() after the driver
already did it.
[ 5.642230] radeon 0000:01:05.0: probe with driver radeon failed with error -22
[ 5.649605] ------------[ cut here ]------------
[ 5.649607] refcount_t: underflow; use-after-free.
[ 5.649620] WARNING: CPU: 0 PID: 357 at lib/refcount.c:28 refcount_warn_saturate+0xbe/0x110
(cherry picked from commit 3eb8c0b4c091da0a623ade0d3ee7aa4a93df1ea4) |
| In the Linux kernel, the following vulnerability has been resolved:
drm/mediatek: Disable AFBC support on Mediatek DRM driver
Commit c410fa9b07c3 ("drm/mediatek: Add AFBC support to Mediatek DRM
driver") added AFBC support to Mediatek DRM and enabled the
32x8/split/sparse modifier.
However, this is currently broken on Mediatek MT8188 (Genio 700 EVK
platform); tested using upstream Kernel and Mesa (v25.2.1), AFBC is used by
default since Mesa v25.0.
Kernel trace reports vblank timeouts constantly, and the render is garbled:
```
[CRTC:62:crtc-0] vblank wait timed out
WARNING: CPU: 7 PID: 70 at drivers/gpu/drm/drm_atomic_helper.c:1835 drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c
[...]
Hardware name: MediaTek Genio-700 EVK (DT)
Workqueue: events_unbound commit_work
pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c
lr : drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c
sp : ffff80008337bca0
x29: ffff80008337bcd0 x28: 0000000000000061 x27: 0000000000000000
x26: 0000000000000001 x25: 0000000000000000 x24: ffff0000c9dcc000
x23: 0000000000000001 x22: 0000000000000000 x21: ffff0000c66f2f80
x20: ffff0000c0d7d880 x19: 0000000000000000 x18: 000000000000000a
x17: 000000040044ffff x16: 005000f2b5503510 x15: 0000000000000000
x14: 0000000000000000 x13: 74756f2064656d69 x12: 742074696177206b
x11: 0000000000000058 x10: 0000000000000018 x9 : ffff800082396a70
x8 : 0000000000057fa8 x7 : 0000000000000cce x6 : ffff8000823eea70
x5 : ffff0001fef5f408 x4 : ffff80017ccee000 x3 : ffff0000c12cb480
x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff0000c12cb480
Call trace:
drm_atomic_helper_wait_for_vblanks.part.0+0x24c/0x27c (P)
drm_atomic_helper_commit_tail_rpm+0x64/0x80
commit_tail+0xa4/0x1a4
commit_work+0x14/0x20
process_one_work+0x150/0x290
worker_thread+0x2d0/0x3ec
kthread+0x12c/0x210
ret_from_fork+0x10/0x20
---[ end trace 0000000000000000 ]---
```
Until this gets fixed upstream, disable AFBC support on this platform, as
it's currently broken with upstream Mesa. |
| In the Linux kernel, the following vulnerability has been resolved:
net: usb: qmi_wwan: initialize MAC header offset in qmimux_rx_fixup
Raw IP packets have no MAC header, leaving skb->mac_header uninitialized.
This can trigger kernel panics on ARM64 when xfrm or other subsystems
access the offset due to strict alignment checks.
Initialize the MAC header to prevent such crashes.
This can trigger kernel panics on ARM when running IPsec over the
qmimux0 interface.
Example trace:
Internal error: Oops: 000000009600004f [#1] SMP
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.34-gbe78e49cb433 #1
Hardware name: LS1028A RDB Board (DT)
pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : xfrm_input+0xde8/0x1318
lr : xfrm_input+0x61c/0x1318
sp : ffff800080003b20
Call trace:
xfrm_input+0xde8/0x1318
xfrm6_rcv+0x38/0x44
xfrm6_esp_rcv+0x48/0xa8
ip6_protocol_deliver_rcu+0x94/0x4b0
ip6_input_finish+0x44/0x70
ip6_input+0x44/0xc0
ipv6_rcv+0x6c/0x114
__netif_receive_skb_one_core+0x5c/0x8c
__netif_receive_skb+0x18/0x60
process_backlog+0x78/0x17c
__napi_poll+0x38/0x180
net_rx_action+0x168/0x2f0 |
| In the Linux kernel, the following vulnerability has been resolved:
crash: fix crashkernel resource shrink
When crashkernel is configured with a high reservation, shrinking its
value below the low crashkernel reservation causes two issues:
1. Invalid crashkernel resource objects
2. Kernel crash if crashkernel shrinking is done twice
For example, with crashkernel=200M,high, the kernel reserves 200MB of high
memory and some default low memory (say 256MB). The reservation appears
as:
cat /proc/iomem | grep -i crash
af000000-beffffff : Crash kernel
433000000-43f7fffff : Crash kernel
If crashkernel is then shrunk to 50MB (echo 52428800 >
/sys/kernel/kexec_crash_size), /proc/iomem still shows 256MB reserved:
af000000-beffffff : Crash kernel
Instead, it should show 50MB:
af000000-b21fffff : Crash kernel
Further shrinking crashkernel to 40MB causes a kernel crash with the
following trace (x86):
BUG: kernel NULL pointer dereference, address: 0000000000000038
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
<snip...>
Call Trace: <TASK>
? __die_body.cold+0x19/0x27
? page_fault_oops+0x15a/0x2f0
? search_module_extables+0x19/0x60
? search_bpf_extables+0x5f/0x80
? exc_page_fault+0x7e/0x180
? asm_exc_page_fault+0x26/0x30
? __release_resource+0xd/0xb0
release_resource+0x26/0x40
__crash_shrink_memory+0xe5/0x110
crash_shrink_memory+0x12a/0x190
kexec_crash_size_store+0x41/0x80
kernfs_fop_write_iter+0x141/0x1f0
vfs_write+0x294/0x460
ksys_write+0x6d/0xf0
<snip...>
This happens because __crash_shrink_memory()/kernel/crash_core.c
incorrectly updates the crashk_res resource object even when
crashk_low_res should be updated.
Fix this by ensuring the correct crashkernel resource object is updated
when shrinking crashkernel memory. |
| In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Fix unsafe locking in the scx_dump_state()
For built with CONFIG_PREEMPT_RT=y kernels, the dump_lock will be converted
sleepable spinlock and not disable-irq, so the following scenarios occur:
inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
irq_work/0/27 [HC0[0]:SC0[0]:HE1:SE1] takes:
(&rq->__lock){?...}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x40
{IN-HARDIRQ-W} state was registered at:
lock_acquire+0x1e1/0x510
_raw_spin_lock_nested+0x42/0x80
raw_spin_rq_lock_nested+0x2b/0x40
sched_tick+0xae/0x7b0
update_process_times+0x14c/0x1b0
tick_periodic+0x62/0x1f0
tick_handle_periodic+0x48/0xf0
timer_interrupt+0x55/0x80
__handle_irq_event_percpu+0x20a/0x5c0
handle_irq_event_percpu+0x18/0xc0
handle_irq_event+0xb5/0x150
handle_level_irq+0x220/0x460
__common_interrupt+0xa2/0x1e0
common_interrupt+0xb0/0xd0
asm_common_interrupt+0x2b/0x40
_raw_spin_unlock_irqrestore+0x45/0x80
__setup_irq+0xc34/0x1a30
request_threaded_irq+0x214/0x2f0
hpet_time_init+0x3e/0x60
x86_late_time_init+0x5b/0xb0
start_kernel+0x308/0x410
x86_64_start_reservations+0x1c/0x30
x86_64_start_kernel+0x96/0xa0
common_startup_64+0x13e/0x148
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&rq->__lock);
<Interrupt>
lock(&rq->__lock);
*** DEADLOCK ***
stack backtrace:
CPU: 0 UID: 0 PID: 27 Comm: irq_work/0
Call Trace:
<TASK>
dump_stack_lvl+0x8c/0xd0
dump_stack+0x14/0x20
print_usage_bug+0x42e/0x690
mark_lock.part.44+0x867/0xa70
? __pfx_mark_lock.part.44+0x10/0x10
? string_nocheck+0x19c/0x310
? number+0x739/0x9f0
? __pfx_string_nocheck+0x10/0x10
? __pfx_check_pointer+0x10/0x10
? kvm_sched_clock_read+0x15/0x30
? sched_clock_noinstr+0xd/0x20
? local_clock_noinstr+0x1c/0xe0
__lock_acquire+0xc4b/0x62b0
? __pfx_format_decode+0x10/0x10
? __pfx_string+0x10/0x10
? __pfx___lock_acquire+0x10/0x10
? __pfx_vsnprintf+0x10/0x10
lock_acquire+0x1e1/0x510
? raw_spin_rq_lock_nested+0x2b/0x40
? __pfx_lock_acquire+0x10/0x10
? dump_line+0x12e/0x270
? raw_spin_rq_lock_nested+0x20/0x40
_raw_spin_lock_nested+0x42/0x80
? raw_spin_rq_lock_nested+0x2b/0x40
raw_spin_rq_lock_nested+0x2b/0x40
scx_dump_state+0x3b3/0x1270
? finish_task_switch+0x27e/0x840
scx_ops_error_irq_workfn+0x67/0x80
irq_work_single+0x113/0x260
irq_work_run_list.part.3+0x44/0x70
run_irq_workd+0x6b/0x90
? __pfx_run_irq_workd+0x10/0x10
smpboot_thread_fn+0x529/0x870
? __pfx_smpboot_thread_fn+0x10/0x10
kthread+0x305/0x3f0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x40/0x70
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
This commit therefore use rq_lock_irqsave/irqrestore() to replace
rq_lock/unlock() in the scx_dump_state(). |
| In the Linux kernel, the following vulnerability has been resolved:
idpf: fix possible vport_config NULL pointer deref in remove
Attempting to remove the driver will cause a crash in cases where
the vport failed to initialize. Following trace is from an instance where
the driver failed during an attempt to create a VF:
[ 1661.543624] idpf 0000:84:00.7: Device HW Reset initiated
[ 1722.923726] idpf 0000:84:00.7: Transaction timed-out (op:1 cookie:2900 vc_op:1 salt:29 timeout:60000ms)
[ 1723.353263] BUG: kernel NULL pointer dereference, address: 0000000000000028
...
[ 1723.358472] RIP: 0010:idpf_remove+0x11c/0x200 [idpf]
...
[ 1723.364973] Call Trace:
[ 1723.365475] <TASK>
[ 1723.365972] pci_device_remove+0x42/0xb0
[ 1723.366481] device_release_driver_internal+0x1a9/0x210
[ 1723.366987] pci_stop_bus_device+0x6d/0x90
[ 1723.367488] pci_stop_and_remove_bus_device+0x12/0x20
[ 1723.367971] pci_iov_remove_virtfn+0xbd/0x120
[ 1723.368309] sriov_disable+0x34/0xe0
[ 1723.368643] idpf_sriov_configure+0x58/0x140 [idpf]
[ 1723.368982] sriov_numvfs_store+0xda/0x1c0
Avoid the NULL pointer dereference by adding NULL pointer check for
vport_config[i], before freeing user_config.q_coalesce. |
| In the Linux kernel, the following vulnerability has been resolved:
net: ethernet: ti: netcp: Standardize knav_dma_open_channel to return NULL on error
Make knav_dma_open_channel consistently return NULL on error instead
of ERR_PTR. Currently the header include/linux/soc/ti/knav_dma.h
returns NULL when the driver is disabled, but the driver
implementation does not even return NULL or ERR_PTR on failure,
causing inconsistency in the users. This results in a crash in
netcp_free_navigator_resources as followed (trimmed):
Unhandled fault: alignment exception (0x221) at 0xfffffff2
[fffffff2] *pgd=80000800207003, *pmd=82ffda003, *pte=00000000
Internal error: : 221 [#1] SMP ARM
Modules linked in:
CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.17.0-rc7 #1 NONE
Hardware name: Keystone
PC is at knav_dma_close_channel+0x30/0x19c
LR is at netcp_free_navigator_resources+0x2c/0x28c
[... TRIM...]
Call trace:
knav_dma_close_channel from netcp_free_navigator_resources+0x2c/0x28c
netcp_free_navigator_resources from netcp_ndo_open+0x430/0x46c
netcp_ndo_open from __dev_open+0x114/0x29c
__dev_open from __dev_change_flags+0x190/0x208
__dev_change_flags from netif_change_flags+0x1c/0x58
netif_change_flags from dev_change_flags+0x38/0xa0
dev_change_flags from ip_auto_config+0x2c4/0x11f0
ip_auto_config from do_one_initcall+0x58/0x200
do_one_initcall from kernel_init_freeable+0x1cc/0x238
kernel_init_freeable from kernel_init+0x1c/0x12c
kernel_init from ret_from_fork+0x14/0x38
[... TRIM...]
Standardize the error handling by making the function return NULL on
all error conditions. The API is used in just the netcp_core.c so the
impact is limited.
Note, this change, in effect reverts commit 5b6cb43b4d62 ("net:
ethernet: ti: netcp_core: return error while dma channel open issue"),
but provides a less error prone implementation. |
| In the Linux kernel, the following vulnerability has been resolved:
pinctrl: s32cc: fix uninitialized memory in s32_pinctrl_desc
s32_pinctrl_desc is allocated with devm_kmalloc(), but not all of its
fields are initialized. Notably, num_custom_params is used in
pinconf_generic_parse_dt_config(), resulting in intermittent allocation
errors, such as the following splat when probing i2c-imx:
WARNING: CPU: 0 PID: 176 at mm/page_alloc.c:4795 __alloc_pages_noprof+0x290/0x300
[...]
Hardware name: NXP S32G3 Reference Design Board 3 (S32G-VNP-RDB3) (DT)
[...]
Call trace:
__alloc_pages_noprof+0x290/0x300 (P)
___kmalloc_large_node+0x84/0x168
__kmalloc_large_node_noprof+0x34/0x120
__kmalloc_noprof+0x2ac/0x378
pinconf_generic_parse_dt_config+0x68/0x1a0
s32_dt_node_to_map+0x104/0x248
dt_to_map_one_config+0x154/0x1d8
pinctrl_dt_to_map+0x12c/0x280
create_pinctrl+0x6c/0x270
pinctrl_get+0xc0/0x170
devm_pinctrl_get+0x50/0xa0
pinctrl_bind_pins+0x60/0x2a0
really_probe+0x60/0x3a0
[...]
__platform_driver_register+0x2c/0x40
i2c_adap_imx_init+0x28/0xff8 [i2c_imx]
[...]
This results in later parse failures that can cause issues in dependent
drivers:
s32g-siul2-pinctrl 4009c240.pinctrl: /soc@0/pinctrl@4009c240/i2c0-pins/i2c0-grp0: could not parse node property
s32g-siul2-pinctrl 4009c240.pinctrl: /soc@0/pinctrl@4009c240/i2c0-pins/i2c0-grp0: could not parse node property
[...]
pca953x 0-0022: failed writing register: -6
i2c i2c-0: IMX I2C adapter registered
s32g-siul2-pinctrl 4009c240.pinctrl: /soc@0/pinctrl@4009c240/i2c2-pins/i2c2-grp0: could not parse node property
s32g-siul2-pinctrl 4009c240.pinctrl: /soc@0/pinctrl@4009c240/i2c2-pins/i2c2-grp0: could not parse node property
i2c i2c-1: IMX I2C adapter registered
s32g-siul2-pinctrl 4009c240.pinctrl: /soc@0/pinctrl@4009c240/i2c4-pins/i2c4-grp0: could not parse node property
s32g-siul2-pinctrl 4009c240.pinctrl: /soc@0/pinctrl@4009c240/i2c4-pins/i2c4-grp0: could not parse node property
i2c i2c-2: IMX I2C adapter registered
Fix this by initializing s32_pinctrl_desc with devm_kzalloc() instead of
devm_kmalloc() in s32_pinctrl_probe(), which sets the previously
uninitialized fields to zero. |
| In the Linux kernel, the following vulnerability has been resolved:
net: netpoll: fix incorrect refcount handling causing incorrect cleanup
commit efa95b01da18 ("netpoll: fix use after free") incorrectly
ignored the refcount and prematurely set dev->npinfo to NULL during
netpoll cleanup, leading to improper behavior and memory leaks.
Scenario causing lack of proper cleanup:
1) A netpoll is associated with a NIC (e.g., eth0) and netdev->npinfo is
allocated, and refcnt = 1
- Keep in mind that npinfo is shared among all netpoll instances. In
this case, there is just one.
2) Another netpoll is also associated with the same NIC and
npinfo->refcnt += 1.
- Now dev->npinfo->refcnt = 2;
- There is just one npinfo associated to the netdev.
3) When the first netpolls goes to clean up:
- The first cleanup succeeds and clears np->dev->npinfo, ignoring
refcnt.
- It basically calls `RCU_INIT_POINTER(np->dev->npinfo, NULL);`
- Set dev->npinfo = NULL, without proper cleanup
- No ->ndo_netpoll_cleanup() is either called
4) Now the second target tries to clean up
- The second cleanup fails because np->dev->npinfo is already NULL.
* In this case, ops->ndo_netpoll_cleanup() was never called, and
the skb pool is not cleaned as well (for the second netpoll
instance)
- This leaks npinfo and skbpool skbs, which is clearly reported by
kmemleak.
Revert commit efa95b01da18 ("netpoll: fix use after free") and adds
clarifying comments emphasizing that npinfo cleanup should only happen
once the refcount reaches zero, ensuring stable and correct netpoll
behavior. |
| In the Linux kernel, the following vulnerability has been resolved:
comedi: multiq3: sanitize config options in multiq3_attach()
Syzbot identified an issue [1] in multiq3_attach() that induces a
task timeout due to open() or COMEDI_DEVCONFIG ioctl operations,
specifically, in the case of multiq3 driver.
This problem arose when syzkaller managed to craft weird configuration
options used to specify the number of channels in encoder subdevice.
If a particularly great number is passed to s->n_chan in
multiq3_attach() via it->options[2], then multiple calls to
multiq3_encoder_reset() at the end of driver-specific attach() method
will be running for minutes, thus blocking tasks and affected devices
as well.
While this issue is most likely not too dangerous for real-life
devices, it still makes sense to sanitize configuration inputs. Enable
a sensible limit on the number of encoder chips (4 chips max, each
with 2 channels) to stop this behaviour from manifesting.
[1] Syzbot crash:
INFO: task syz.2.19:6067 blocked for more than 143 seconds.
...
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5254 [inline]
__schedule+0x17c4/0x4d60 kernel/sched/core.c:6862
__schedule_loop kernel/sched/core.c:6944 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6959
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7016
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
comedi_open+0xc0/0x590 drivers/comedi/comedi_fops.c:2868
chrdev_open+0x4cc/0x5e0 fs/char_dev.c:414
do_dentry_open+0x953/0x13f0 fs/open.c:965
vfs_open+0x3b/0x340 fs/open.c:1097
... |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: SVM: Don't skip unrelated instruction if INT3/INTO is replaced
When re-injecting a soft interrupt from an INT3, INT0, or (select) INTn
instruction, discard the exception and retry the instruction if the code
stream is changed (e.g. by a different vCPU) between when the CPU
executes the instruction and when KVM decodes the instruction to get the
next RIP.
As effectively predicted by commit 6ef88d6e36c2 ("KVM: SVM: Re-inject
INT3/INTO instead of retrying the instruction"), failure to verify that
the correct INTn instruction was decoded can effectively clobber guest
state due to decoding the wrong instruction and thus specifying the
wrong next RIP.
The bug most often manifests as "Oops: int3" panics on static branch
checks in Linux guests. Enabling or disabling a static branch in Linux
uses the kernel's "text poke" code patching mechanism. To modify code
while other CPUs may be executing that code, Linux (temporarily)
replaces the first byte of the original instruction with an int3 (opcode
0xcc), then patches in the new code stream except for the first byte,
and finally replaces the int3 with the first byte of the new code
stream. If a CPU hits the int3, i.e. executes the code while it's being
modified, then the guest kernel must look up the RIP to determine how to
handle the #BP, e.g. by emulating the new instruction. If the RIP is
incorrect, then this lookup fails and the guest kernel panics.
The bug reproduces almost instantly by hacking the guest kernel to
repeatedly check a static branch[1] while running a drgn script[2] on
the host to constantly swap out the memory containing the guest's TSS.
[1]: https://gist.github.com/osandov/44d17c51c28c0ac998ea0334edf90b5a
[2]: https://gist.github.com/osandov/10e45e45afa29b11e0c7209247afc00b |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: udc: fix use-after-free in usb_gadget_state_work
A race condition during gadget teardown can lead to a use-after-free
in usb_gadget_state_work(), as reported by KASAN:
BUG: KASAN: invalid-access in sysfs_notify+0x2c/0xd0
Workqueue: events usb_gadget_state_work
The fundamental race occurs because a concurrent event (e.g., an
interrupt) can call usb_gadget_set_state() and schedule gadget->work
at any time during the cleanup process in usb_del_gadget().
Commit 399a45e5237c ("usb: gadget: core: flush gadget workqueue after
device removal") attempted to fix this by moving flush_work() to after
device_del(). However, this does not fully solve the race, as a new
work item can still be scheduled *after* flush_work() completes but
before the gadget's memory is freed, leading to the same use-after-free.
This patch fixes the race condition robustly by introducing a 'teardown'
flag and a 'state_lock' spinlock to the usb_gadget struct. The flag is
set during cleanup in usb_del_gadget() *before* calling flush_work() to
prevent any new work from being scheduled once cleanup has commenced.
The scheduling site, usb_gadget_set_state(), now checks this flag under
the lock before queueing the work, thus safely closing the race window. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_eem: Fix memory leak in eem_unwrap
The existing code did not handle the failure case of usb_ep_queue in the
command path, potentially leading to memory leaks.
Improve error handling to free all allocated resources on usb_ep_queue
failure. This patch continues to use goto logic for error handling, as the
existing error handling is complex and not easily adaptable to auto-cleanup
helpers.
kmemleak results:
unreferenced object 0xffffff895a512300 (size 240):
backtrace:
slab_post_alloc_hook+0xbc/0x3a4
kmem_cache_alloc+0x1b4/0x358
skb_clone+0x90/0xd8
eem_unwrap+0x1cc/0x36c
unreferenced object 0xffffff8a157f4000 (size 256):
backtrace:
slab_post_alloc_hook+0xbc/0x3a4
__kmem_cache_alloc_node+0x1b4/0x2dc
kmalloc_trace+0x48/0x140
dwc3_gadget_ep_alloc_request+0x58/0x11c
usb_ep_alloc_request+0x40/0xe4
eem_unwrap+0x204/0x36c
unreferenced object 0xffffff8aadbaac00 (size 128):
backtrace:
slab_post_alloc_hook+0xbc/0x3a4
__kmem_cache_alloc_node+0x1b4/0x2dc
__kmalloc+0x64/0x1a8
eem_unwrap+0x218/0x36c
unreferenced object 0xffffff89ccef3500 (size 64):
backtrace:
slab_post_alloc_hook+0xbc/0x3a4
__kmem_cache_alloc_node+0x1b4/0x2dc
kmalloc_trace+0x48/0x140
eem_unwrap+0x238/0x36c |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: btusb: mediatek: Avoid btusb_mtk_claim_iso_intf() NULL deref
In btusb_mtk_setup(), we set `btmtk_data->isopkt_intf` to:
usb_ifnum_to_if(data->udev, MTK_ISO_IFNUM)
That function can return NULL in some cases. Even when it returns
NULL, though, we still go on to call btusb_mtk_claim_iso_intf().
As of commit e9087e828827 ("Bluetooth: btusb: mediatek: Add locks for
usb_driver_claim_interface()"), calling btusb_mtk_claim_iso_intf()
when `btmtk_data->isopkt_intf` is NULL will cause a crash because
we'll end up passing a bad pointer to device_lock(). Prior to that
commit we'd pass the NULL pointer directly to
usb_driver_claim_interface() which would detect it and return an
error, which was handled.
Resolve the crash in btusb_mtk_claim_iso_intf() by adding a NULL check
at the start of the function. This makes the code handle a NULL
`btmtk_data->isopkt_intf` the same way it did before the problematic
commit (just with a slight change to the error message printed). |
| In the Linux kernel, the following vulnerability has been resolved:
afs: Fix delayed allocation of a cell's anonymous key
The allocation of a cell's anonymous key is done in a background thread
along with other cell setup such as doing a DNS upcall. In the reported
bug, this is triggered by afs_parse_source() parsing the device name given
to mount() and calling afs_lookup_cell() with the name of the cell.
The normal key lookup then tries to use the key description on the
anonymous authentication key as the reference for request_key() - but it
may not yet be set and so an oops can happen.
This has been made more likely to happen by the fix for dynamic lookup
failure.
Fix this by firstly allocating a reference name and attaching it to the
afs_cell record when the record is created. It can share the memory
allocation with the cell name (unfortunately it can't just overlap the cell
name by prepending it with "afs@" as the cell name already has a '.'
prepended for other purposes). This reference name is then passed to
request_key().
Secondly, the anon key is now allocated on demand at the point a key is
requested in afs_request_key() if it is not already allocated. A mutex is
used to prevent multiple allocation for a cell.
Thirdly, make afs_request_key_rcu() return NULL if the anonymous key isn't
yet allocated (if we need it) and then the caller can return -ECHILD to
drop out of RCU-mode and afs_request_key() can be called.
Note that the anonymous key is kind of necessary to make the key lookup
cache work as that doesn't currently cache a negative lookup, but it's
probably worth some investigation to see if NULL can be used instead. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_core: lookup hci_conn on RX path on protocol side
The hdev lock/lookup/unlock/use pattern in the packet RX path doesn't
ensure hci_conn* is not concurrently modified/deleted. This locking
appears to be leftover from before conn_hash started using RCU
commit bf4c63252490b ("Bluetooth: convert conn hash to RCU")
and not clear if it had purpose since then.
Currently, there are code paths that delete hci_conn* from elsewhere
than the ordered hdev->workqueue where the RX work runs in. E.g.
commit 5af1f84ed13a ("Bluetooth: hci_sync: Fix UAF on hci_abort_conn_sync")
introduced some of these, and there probably were a few others before
it. It's better to do the locking so that even if these run
concurrently no UAF is possible.
Move the lookup of hci_conn and associated socket-specific conn to
protocol recv handlers, and do them within a single critical section
to cover hci_conn* usage and lookup.
syzkaller has reported a crash that appears to be this issue:
[Task hdev->workqueue] [Task 2]
hci_disconnect_all_sync
l2cap_recv_acldata(hcon)
hci_conn_get(hcon)
hci_abort_conn_sync(hcon)
hci_dev_lock
hci_dev_lock
hci_conn_del(hcon)
v-------------------------------- hci_dev_unlock
hci_conn_put(hcon)
conn = hcon->l2cap_data (UAF) |
| In the Linux kernel, the following vulnerability has been resolved:
netconsole: Acquire su_mutex before navigating configs hierarchy
There is a race between operations that iterate over the userdata
cg_children list and concurrent add/remove of userdata items through
configfs. The update_userdata() function iterates over the
nt->userdata_group.cg_children list, and count_extradata_entries() also
iterates over this same list to count nodes.
Quoting from Documentation/filesystems/configfs.rst:
> A subsystem can navigate the cg_children list and the ci_parent pointer
> to see the tree created by the subsystem. This can race with configfs'
> management of the hierarchy, so configfs uses the subsystem mutex to
> protect modifications. Whenever a subsystem wants to navigate the
> hierarchy, it must do so under the protection of the subsystem
> mutex.
Without proper locking, if a userdata item is added or removed
concurrently while these functions are iterating, the list can be
accessed in an inconsistent state. For example, the list_for_each() loop
can reach a node that is being removed from the list by list_del_init()
which sets the nodes' .next pointer to point to itself, so the loop will
never end (or reach the WARN_ON_ONCE in update_userdata() ).
Fix this by holding the configfs subsystem mutex (su_mutex) during all
operations that iterate over cg_children.
This includes:
- userdatum_value_store() which calls update_userdata() to iterate over
cg_children
- All sysdata_*_enabled_store() functions which call
count_extradata_entries() to iterate over cg_children
The su_mutex must be acquired before dynamic_netconsole_mutex to avoid
potential lock ordering issues, as configfs operations may already hold
su_mutex when calling into our code. |
