| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
s390/pci: Avoid deadlock between PCI error recovery and mlx5 crdump
Do not block PCI config accesses through pci_cfg_access_lock() when
executing the s390 variant of PCI error recovery: Acquire just
device_lock() instead of pci_dev_lock() as powerpc's EEH and
generig PCI AER processing do.
During error recovery testing a pair of tasks was reported to be hung:
mlx5_core 0000:00:00.1: mlx5_health_try_recover:338:(pid 5553): health recovery flow aborted, PCI reads still not working
INFO: task kmcheck:72 blocked for more than 122 seconds.
Not tainted 5.14.0-570.12.1.bringup7.el9.s390x #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kmcheck state:D stack:0 pid:72 tgid:72 ppid:2 flags:0x00000000
Call Trace:
[<000000065256f030>] __schedule+0x2a0/0x590
[<000000065256f356>] schedule+0x36/0xe0
[<000000065256f572>] schedule_preempt_disabled+0x22/0x30
[<0000000652570a94>] __mutex_lock.constprop.0+0x484/0x8a8
[<000003ff800673a4>] mlx5_unload_one+0x34/0x58 [mlx5_core]
[<000003ff8006745c>] mlx5_pci_err_detected+0x94/0x140 [mlx5_core]
[<0000000652556c5a>] zpci_event_attempt_error_recovery+0xf2/0x398
[<0000000651b9184a>] __zpci_event_error+0x23a/0x2c0
INFO: task kworker/u1664:6:1514 blocked for more than 122 seconds.
Not tainted 5.14.0-570.12.1.bringup7.el9.s390x #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u1664:6 state:D stack:0 pid:1514 tgid:1514 ppid:2 flags:0x00000000
Workqueue: mlx5_health0000:00:00.0 mlx5_fw_fatal_reporter_err_work [mlx5_core]
Call Trace:
[<000000065256f030>] __schedule+0x2a0/0x590
[<000000065256f356>] schedule+0x36/0xe0
[<0000000652172e28>] pci_wait_cfg+0x80/0xe8
[<0000000652172f94>] pci_cfg_access_lock+0x74/0x88
[<000003ff800916b6>] mlx5_vsc_gw_lock+0x36/0x178 [mlx5_core]
[<000003ff80098824>] mlx5_crdump_collect+0x34/0x1c8 [mlx5_core]
[<000003ff80074b62>] mlx5_fw_fatal_reporter_dump+0x6a/0xe8 [mlx5_core]
[<0000000652512242>] devlink_health_do_dump.part.0+0x82/0x168
[<0000000652513212>] devlink_health_report+0x19a/0x230
[<000003ff80075a12>] mlx5_fw_fatal_reporter_err_work+0xba/0x1b0 [mlx5_core]
No kernel log of the exact same error with an upstream kernel is
available - but the very same deadlock situation can be constructed there,
too:
- task: kmcheck
mlx5_unload_one() tries to acquire devlink lock while the PCI error
recovery code has set pdev->block_cfg_access by way of
pci_cfg_access_lock()
- task: kworker
mlx5_crdump_collect() tries to set block_cfg_access through
pci_cfg_access_lock() while devlink_health_report() had acquired
the devlink lock.
A similar deadlock situation can be reproduced by requesting a
crdump with
> devlink health dump show pci/<BDF> reporter fw_fatal
while PCI error recovery is executed on the same <BDF> physical function
by mlx5_core's pci_error_handlers. On s390 this can be injected with
> zpcictl --reset-fw <BDF>
Tests with this patch failed to reproduce that second deadlock situation,
the devlink command is rejected with "kernel answers: Permission denied" -
and we get a kernel log message of:
mlx5_core 1ed0:00:00.1: mlx5_crdump_collect:50:(pid 254382): crdump: failed to lock vsc gw err -5
because the config read of VSC_SEMAPHORE is rejected by the underlying
hardware.
Two prior attempts to address this issue have been discussed and
ultimately rejected [see link], with the primary argument that s390's
implementation of PCI error recovery is imposing restrictions that
neither powerpc's EEH nor PCI AER handling need. Tests show that PCI
error recovery on s390 is running to completion even without blocking
access to PCI config space. |
| In the Linux kernel, the following vulnerability has been resolved:
lan966x: Fix sleeping in atomic context
The following warning was seen when we try to connect using ssh to the device.
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:575
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 104, name: dropbear
preempt_count: 1, expected: 0
INFO: lockdep is turned off.
CPU: 0 UID: 0 PID: 104 Comm: dropbear Tainted: G W 6.18.0-rc2-00399-g6f1ab1b109b9-dirty #530 NONE
Tainted: [W]=WARN
Hardware name: Generic DT based system
Call trace:
unwind_backtrace from show_stack+0x10/0x14
show_stack from dump_stack_lvl+0x7c/0xac
dump_stack_lvl from __might_resched+0x16c/0x2b0
__might_resched from __mutex_lock+0x64/0xd34
__mutex_lock from mutex_lock_nested+0x1c/0x24
mutex_lock_nested from lan966x_stats_get+0x5c/0x558
lan966x_stats_get from dev_get_stats+0x40/0x43c
dev_get_stats from dev_seq_printf_stats+0x3c/0x184
dev_seq_printf_stats from dev_seq_show+0x10/0x30
dev_seq_show from seq_read_iter+0x350/0x4ec
seq_read_iter from seq_read+0xfc/0x194
seq_read from proc_reg_read+0xac/0x100
proc_reg_read from vfs_read+0xb0/0x2b0
vfs_read from ksys_read+0x6c/0xec
ksys_read from ret_fast_syscall+0x0/0x1c
Exception stack(0xf0b11fa8 to 0xf0b11ff0)
1fa0: 00000001 00001000 00000008 be9048d8 00001000 00000001
1fc0: 00000001 00001000 00000008 00000003 be905920 0000001e 00000000 00000001
1fe0: 0005404c be9048c0 00018684 b6ec2cd8
It seems that we are using a mutex in a atomic context which is wrong.
Change the mutex with a spinlock. |
| 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:
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:
cifs: fix memory leak in smb3_fs_context_parse_param error path
Add proper cleanup of ctx->source and fc->source to the
cifs_parse_mount_err error handler. This ensures that memory allocated
for the source strings is correctly freed on all error paths, matching
the cleanup already performed in the success path by
smb3_cleanup_fs_context_contents().
Pointers are also set to NULL after freeing to prevent potential
double-free issues.
This change fixes a memory leak originally detected by syzbot. The
leak occurred when processing Opt_source mount options if an error
happened after ctx->source and fc->source were successfully
allocated but before the function completed.
The specific leak sequence was:
1. ctx->source = smb3_fs_context_fullpath(ctx, '/') allocates memory
2. fc->source = kstrdup(ctx->source, GFP_KERNEL) allocates more memory
3. A subsequent error jumps to cifs_parse_mount_err
4. The old error handler freed passwords but not the source strings,
causing the memory to leak.
This issue was not addressed by commit e8c73eb7db0a ("cifs: client:
fix memory leak in smb3_fs_context_parse_param"), which only fixed
leaks from repeated fsconfig() calls but not this error path.
Patch updated with minor change suggested by kernel test robot |
| 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:
can: kvaser_usb: leaf: Fix potential infinite loop in command parsers
The `kvaser_usb_leaf_wait_cmd()` and `kvaser_usb_leaf_read_bulk_callback`
functions contain logic to zero-length commands. These commands are used
to align data to the USB endpoint's wMaxPacketSize boundary.
The driver attempts to skip these placeholders by aligning the buffer
position `pos` to the next packet boundary using `round_up()` function.
However, if zero-length command is found exactly on a packet boundary
(i.e., `pos` is a multiple of wMaxPacketSize, including 0), `round_up`
function will return the unchanged value of `pos`. This prevents `pos`
to be increased, causing an infinite loop in the parsing logic.
This patch fixes this in the function by using `pos + 1` instead.
This ensures that even if `pos` is on a boundary, the calculation is
based on `pos + 1`, forcing `round_up()` to always return the next
aligned boundary. |
| In the Linux kernel, the following vulnerability has been resolved:
mtdchar: fix integer overflow in read/write ioctls
The "req.start" and "req.len" variables are u64 values that come from the
user at the start of the function. We mask away the high 32 bits of
"req.len" so that's capped at U32_MAX but the "req.start" variable can go
up to U64_MAX which means that the addition can still integer overflow.
Use check_add_overflow() to fix this bug. |
| In the Linux kernel, the following vulnerability has been resolved:
timers: Fix NULL function pointer race in timer_shutdown_sync()
There is a race condition between timer_shutdown_sync() and timer
expiration that can lead to hitting a WARN_ON in expire_timers().
The issue occurs when timer_shutdown_sync() clears the timer function
to NULL while the timer is still running on another CPU. The race
scenario looks like this:
CPU0 CPU1
<SOFTIRQ>
lock_timer_base()
expire_timers()
base->running_timer = timer;
unlock_timer_base()
[call_timer_fn enter]
mod_timer()
...
timer_shutdown_sync()
lock_timer_base()
// For now, will not detach the timer but only clear its function to NULL
if (base->running_timer != timer)
ret = detach_if_pending(timer, base, true);
if (shutdown)
timer->function = NULL;
unlock_timer_base()
[call_timer_fn exit]
lock_timer_base()
base->running_timer = NULL;
unlock_timer_base()
...
// Now timer is pending while its function set to NULL.
// next timer trigger
<SOFTIRQ>
expire_timers()
WARN_ON_ONCE(!fn) // hit
...
lock_timer_base()
// Now timer will detach
if (base->running_timer != timer)
ret = detach_if_pending(timer, base, true);
if (shutdown)
timer->function = NULL;
unlock_timer_base()
The problem is that timer_shutdown_sync() clears the timer function
regardless of whether the timer is currently running. This can leave a
pending timer with a NULL function pointer, which triggers the
WARN_ON_ONCE(!fn) check in expire_timers().
Fix this by only clearing the timer function when actually detaching the
timer. If the timer is running, leave the function pointer intact, which is
safe because the timer will be properly detached when it finishes running. |
| 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:
mm/mempool: fix poisoning order>0 pages with HIGHMEM
The kernel test has reported:
BUG: unable to handle page fault for address: fffba000
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
*pde = 03171067 *pte = 00000000
Oops: Oops: 0002 [#1]
CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Tainted: G T 6.18.0-rc2-00031-gec7f31b2a2d3 #1 NONE a1d066dfe789f54bc7645c7989957d2bdee593ca
Tainted: [T]=RANDSTRUCT
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
EIP: memset (arch/x86/include/asm/string_32.h:168 arch/x86/lib/memcpy_32.c:17)
Code: a5 8b 4d f4 83 e1 03 74 02 f3 a4 83 c4 04 5e 5f 5d 2e e9 73 41 01 00 90 90 90 3e 8d 74 26 00 55 89 e5 57 56 89 c6 89 d0 89 f7 <f3> aa 89 f0 5e 5f 5d 2e e9 53 41 01 00 cc cc cc 55 89 e5 53 57 56
EAX: 0000006b EBX: 00000015 ECX: 001fefff EDX: 0000006b
ESI: fffb9000 EDI: fffba000 EBP: c611fbf0 ESP: c611fbe8
DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 EFLAGS: 00010287
CR0: 80050033 CR2: fffba000 CR3: 0316e000 CR4: 00040690
Call Trace:
poison_element (mm/mempool.c:83 mm/mempool.c:102)
mempool_init_node (mm/mempool.c:142 mm/mempool.c:226)
mempool_init_noprof (mm/mempool.c:250 (discriminator 1))
? mempool_alloc_pages (mm/mempool.c:640)
bio_integrity_initfn (block/bio-integrity.c:483 (discriminator 8))
? mempool_alloc_pages (mm/mempool.c:640)
do_one_initcall (init/main.c:1283)
Christoph found out this is due to the poisoning code not dealing
properly with CONFIG_HIGHMEM because only the first page is mapped but
then the whole potentially high-order page is accessed.
We could give up on HIGHMEM here, but it's straightforward to fix this
with a loop that's mapping, poisoning or checking and unmapping
individual pages. |
| In the Linux kernel, the following vulnerability has been resolved:
lib/test_kho: check if KHO is enabled
We must check whether KHO is enabled prior to issuing KHO commands,
otherwise KHO internal data structures are not initialized. |
| In the Linux kernel, the following vulnerability has been resolved:
mptcp: fix address removal logic in mptcp_pm_nl_rm_addr
Fix inverted WARN_ON_ONCE condition that prevented normal address
removal counter updates. The current code only executes decrement
logic when the counter is already 0 (abnormal state), while
normal removals (counter > 0) are ignored. |
| In the Linux kernel, the following vulnerability has been resolved:
veth: more robust handing of race to avoid txq getting stuck
Commit dc82a33297fc ("veth: apply qdisc backpressure on full ptr_ring to
reduce TX drops") introduced a race condition that can lead to a permanently
stalled TXQ. This was observed in production on ARM64 systems (Ampere Altra
Max).
The race occurs in veth_xmit(). The producer observes a full ptr_ring and
stops the queue (netif_tx_stop_queue()). The subsequent conditional logic,
intended to re-wake the queue if the consumer had just emptied it (if
(__ptr_ring_empty(...)) netif_tx_wake_queue()), can fail. This leads to a
"lost wakeup" where the TXQ remains stopped (QUEUE_STATE_DRV_XOFF) and
traffic halts.
This failure is caused by an incorrect use of the __ptr_ring_empty() API
from the producer side. As noted in kernel comments, this check is not
guaranteed to be correct if a consumer is operating on another CPU. The
empty test is based on ptr_ring->consumer_head, making it reliable only for
the consumer. Using this check from the producer side is fundamentally racy.
This patch fixes the race by adopting the more robust logic from an earlier
version V4 of the patchset, which always flushed the peer:
(1) In veth_xmit(), the racy conditional wake-up logic and its memory barrier
are removed. Instead, after stopping the queue, we unconditionally call
__veth_xdp_flush(rq). This guarantees that the NAPI consumer is scheduled,
making it solely responsible for re-waking the TXQ.
This handles the race where veth_poll() consumes all packets and completes
NAPI *before* veth_xmit() on the producer side has called netif_tx_stop_queue.
The __veth_xdp_flush(rq) will observe rx_notify_masked is false and schedule
NAPI.
(2) On the consumer side, the logic for waking the peer TXQ is moved out of
veth_xdp_rcv() and placed at the end of the veth_poll() function. This
placement is part of fixing the race, as the netif_tx_queue_stopped() check
must occur after rx_notify_masked is potentially set to false during NAPI
completion.
This handles the race where veth_poll() consumes all packets, but haven't
finished (rx_notify_masked is still true). The producer veth_xmit() stops the
TXQ and __veth_xdp_flush(rq) will observe rx_notify_masked is true, meaning
not starting NAPI. Then veth_poll() change rx_notify_masked to false and
stops NAPI. Before exiting veth_poll() will observe TXQ is stopped and wake
it up. |
| In the Linux kernel, the following vulnerability has been resolved:
nouveau/firmware: Add missing kfree() of nvkm_falcon_fw::boot
nvkm_falcon_fw::boot is allocated, but no one frees it. This causes a
kmemleak warning.
Make sure this data is deallocated. |
| In the Linux kernel, the following vulnerability has been resolved:
tcp_metrics: use dst_dev_net_rcu()
Replace three dst_dev() with a lockdep enabled helper. |
| In the Linux kernel, the following vulnerability has been resolved:
video: fbdev: nvidiafb: Use strscpy() to prevent buffer overflow
Coverity complains of a possible buffer overflow. However,
given the 'static' scope of nvidia_setup_i2c_bus() it looks
like that can't happen after examiniing the call sites.
CID 19036 (#1 of 1): Copy into fixed size buffer (STRING_OVERFLOW)
1. fixed_size_dest: You might overrun the 48-character fixed-size string
chan->adapter.name by copying name without checking the length.
2. parameter_as_source: Note: This defect has an elevated risk because the
source argument is a parameter of the current function.
89 strcpy(chan->adapter.name, name);
Fix this warning by using strscpy() which will silence the warning and
prevent any future buffer overflows should the names used to identify the
channel become much longer. |
| In the Linux kernel, the following vulnerability has been resolved:
video: fbdev: cirrusfb: check pixclock to avoid divide by zero
Do a sanity check on pixclock value to avoid divide by zero.
If the pixclock value is zero, the cirrusfb driver will round up
pixclock to get the derived frequency as close to maxclock as
possible.
Syzkaller reported a divide error in cirrusfb_check_pixclock.
divide error: 0000 [#1] SMP KASAN PTI
CPU: 0 PID: 14938 Comm: cirrusfb_test Not tainted 5.15.0-rc6 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2
RIP: 0010:cirrusfb_check_var+0x6f1/0x1260
Call Trace:
fb_set_var+0x398/0xf90
do_fb_ioctl+0x4b8/0x6f0
fb_ioctl+0xeb/0x130
__x64_sys_ioctl+0x19d/0x220
do_syscall_64+0x3a/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xae |
| In the Linux kernel, the following vulnerability has been resolved:
powerpc/set_memory: Avoid spinlock recursion in change_page_attr()
Commit 1f9ad21c3b38 ("powerpc/mm: Implement set_memory() routines")
included a spin_lock() to change_page_attr() in order to
safely perform the three step operations. But then
commit 9f7853d7609d ("powerpc/mm: Fix set_memory_*() against
concurrent accesses") modify it to use pte_update() and do
the operation safely against concurrent access.
In the meantime, Maxime reported some spinlock recursion.
[ 15.351649] BUG: spinlock recursion on CPU#0, kworker/0:2/217
[ 15.357540] lock: init_mm+0x3c/0x420, .magic: dead4ead, .owner: kworker/0:2/217, .owner_cpu: 0
[ 15.366563] CPU: 0 PID: 217 Comm: kworker/0:2 Not tainted 5.15.0+ #523
[ 15.373350] Workqueue: events do_free_init
[ 15.377615] Call Trace:
[ 15.380232] [e4105ac0] [800946a4] do_raw_spin_lock+0xf8/0x120 (unreliable)
[ 15.387340] [e4105ae0] [8001f4ec] change_page_attr+0x40/0x1d4
[ 15.393413] [e4105b10] [801424e0] __apply_to_page_range+0x164/0x310
[ 15.400009] [e4105b60] [80169620] free_pcp_prepare+0x1e4/0x4a0
[ 15.406045] [e4105ba0] [8016c5a0] free_unref_page+0x40/0x2b8
[ 15.411979] [e4105be0] [8018724c] kasan_depopulate_vmalloc_pte+0x6c/0x94
[ 15.418989] [e4105c00] [801424e0] __apply_to_page_range+0x164/0x310
[ 15.425451] [e4105c50] [80187834] kasan_release_vmalloc+0xbc/0x134
[ 15.431898] [e4105c70] [8015f7a8] __purge_vmap_area_lazy+0x4e4/0xdd8
[ 15.438560] [e4105d30] [80160d10] _vm_unmap_aliases.part.0+0x17c/0x24c
[ 15.445283] [e4105d60] [801642d0] __vunmap+0x2f0/0x5c8
[ 15.450684] [e4105db0] [800e32d0] do_free_init+0x68/0x94
[ 15.456181] [e4105dd0] [8005d094] process_one_work+0x4bc/0x7b8
[ 15.462283] [e4105e90] [8005d614] worker_thread+0x284/0x6e8
[ 15.468227] [e4105f00] [8006aaec] kthread+0x1f0/0x210
[ 15.473489] [e4105f40] [80017148] ret_from_kernel_thread+0x14/0x1c
Remove the read / modify / write sequence to make the operation atomic
and remove the spin_lock() in change_page_attr().
To do the operation atomically, we can't use pte modification helpers
anymore. Because all platforms have different combination of bits, it
is not easy to use those bits directly. But all have the
_PAGE_KERNEL_{RO/ROX/RW/RWX} set of flags. All we need it to compare
two sets to know which bits are set or cleared.
For instance, by comparing _PAGE_KERNEL_ROX and _PAGE_KERNEL_RO you
know which bit gets cleared and which bit get set when changing exec
permission. |
| In the Linux kernel, the following vulnerability has been resolved:
powerpc/fixmap: Fix VM debug warning on unmap
Unmapping a fixmap entry is done by calling __set_fixmap()
with FIXMAP_PAGE_CLEAR as flags.
Today, powerpc __set_fixmap() calls map_kernel_page().
map_kernel_page() is not happy when called a second time
for the same page.
WARNING: CPU: 0 PID: 1 at arch/powerpc/mm/pgtable.c:194 set_pte_at+0xc/0x1e8
CPU: 0 PID: 1 Comm: swapper Not tainted 5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty #682
NIP: c0017cd4 LR: c00187f0 CTR: 00000010
REGS: e1011d50 TRAP: 0700 Not tainted (5.16.0-rc3-s3k-dev-01993-g350ff07feb7d-dirty)
MSR: 00029032 <EE,ME,IR,DR,RI> CR: 42000208 XER: 00000000
GPR00: c0165fec e1011e10 c14c0000 c0ee2550 ff800000 c0f3d000 00000000 c001686c
GPR08: 00001000 b00045a9 00000001 c0f58460 c0f50000 00000000 c0007e10 00000000
GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
GPR24: 00000000 00000000 c0ee2550 00000000 c0f57000 00000ff8 00000000 ff800000
NIP [c0017cd4] set_pte_at+0xc/0x1e8
LR [c00187f0] map_kernel_page+0x9c/0x100
Call Trace:
[e1011e10] [c0736c68] vsnprintf+0x358/0x6c8 (unreliable)
[e1011e30] [c0165fec] __set_fixmap+0x30/0x44
[e1011e40] [c0c13bdc] early_iounmap+0x11c/0x170
[e1011e70] [c0c06cb0] ioremap_legacy_serial_console+0x88/0xc0
[e1011e90] [c0c03634] do_one_initcall+0x80/0x178
[e1011ef0] [c0c0385c] kernel_init_freeable+0xb4/0x250
[e1011f20] [c0007e34] kernel_init+0x24/0x140
[e1011f30] [c0016268] ret_from_kernel_thread+0x5c/0x64
Instruction dump:
7fe3fb78 48019689 80010014 7c630034 83e1000c 5463d97e 7c0803a6 38210010
4e800020 81250000 712a0001 41820008 <0fe00000> 9421ffe0 93e1001c 48000030
Implement unmap_kernel_page() which clears an existing pte. |
