In the Linux kernel, the following vulnerability has been resolved:
net: hinic: avoid kernel hung in hinic_get_stats64()
When using hinic device as a bond slave device, and reading device stats
of master bond device, the kernel may hung.
The kernel panic calltrace as follows:
Kernel panic - not syncing: softlockup: hung tasks
Call trace:
native_queued_spin_lock_slowpath+0x1ec/0x31c
dev_get_stats+0x60/0xcc
dev_seq_printf_stats+0x40/0x120
dev_seq_show+0x1c/0x40
seq_read_iter+0x3c8/0x4dc
seq_read+0xe0/0x130
proc_reg_read+0xa8/0xe0
vfs_read+0xb0/0x1d4
ksys_read+0x70/0xfc
__arm64_sys_read+0x20/0x30
el0_svc_common+0x88/0x234
do_el0_svc+0x2c/0x90
el0_svc+0x1c/0x30
el0_sync_handler+0xa8/0xb0
el0_sync+0x148/0x180
And the calltrace of task that actually caused kernel hungs as follows:
__switch_to+124
__schedule+548
schedule+72
schedule_timeout+348
__down_common+188
__down+24
down+104
hinic_get_stats64+44 [hinic]
dev_get_stats+92
bond_get_stats+172 [bonding]
dev_get_stats+92
dev_seq_printf_stats+60
dev_seq_show+24
seq_read_iter+964
seq_read+220
proc_reg_read+164
vfs_read+172
ksys_read+108
__arm64_sys_read+28
el0_svc_common+132
do_el0_svc+40
el0_svc+24
el0_sync_handler+164
el0_sync+324
When getting device stats from bond, kernel will call bond_get_stats().
It first holds the spinlock bond->stats_lock, and then call
hinic_get_stats64() to collect hinic device's stats.
However, hinic_get_stats64() calls `down(&nic_dev->mgmt_lock)` to
protect its critical section, which may schedule current task out.
And if system is under high pressure, the task cannot be woken up
immediately, which eventually triggers kernel hung panic.
Since previous patch has replaced hinic_dev.tx_stats/rx_stats with local
variable in hinic_get_stats64(), there is nothing need to be protected
by lock, so just removing down()/up() is ok.
In the Linux kernel, the following vulnerability has been resolved:
media: tw686x: Fix memory leak in tw686x_video_init
video_device_alloc() allocates memory for vdev,
when video_register_device() fails, it doesn't release the memory and
leads to memory leak, call video_device_release() to fix this.
In the Linux kernel, the following vulnerability has been resolved:
of: check previous kernel's ima-kexec-buffer against memory bounds
Presently ima_get_kexec_buffer() doesn't check if the previous kernel's
ima-kexec-buffer lies outside the addressable memory range. This can result
in a kernel panic if the new kernel is booted with 'mem=X' arg and the
ima-kexec-buffer was allocated beyond that range by the previous kernel.
The panic is usually of the form below:
$ sudo kexec --initrd initrd vmlinux --append='mem=16G'
<snip>
BUG: Unable to handle kernel data access on read at 0xc000c01fff7f0000
Faulting instruction address: 0xc000000000837974
Oops: Kernel access of bad area, sig: 11 [#1]
<snip>
NIP [c000000000837974] ima_restore_measurement_list+0x94/0x6c0
LR [c00000000083b55c] ima_load_kexec_buffer+0xac/0x160
Call Trace:
[c00000000371fa80] [c00000000083b55c] ima_load_kexec_buffer+0xac/0x160
[c00000000371fb00] [c0000000020512c4] ima_init+0x80/0x108
[c00000000371fb70] [c0000000020514dc] init_ima+0x4c/0x120
[c00000000371fbf0] [c000000000012240] do_one_initcall+0x60/0x2c0
[c00000000371fcc0] [c000000002004ad0] kernel_init_freeable+0x344/0x3ec
[c00000000371fda0] [c0000000000128a4] kernel_init+0x34/0x1b0
[c00000000371fe10] [c00000000000ce64] ret_from_kernel_thread+0x5c/0x64
Instruction dump:
f92100b8 f92100c0 90e10090 910100a0 4182050c 282a0017 3bc00000 40810330
7c0802a6 fb610198 7c9b2378 f80101d0 <a1240000> 2c090001 40820614 e9240010
---[ end trace 0000000000000000 ]---
Fix this issue by checking returned PFN range of previous kernel's
ima-kexec-buffer with page_is_ram() to ensure correct memory bounds.
In the Linux kernel, the following vulnerability has been resolved:
mtd: maps: Fix refcount leak in ap_flash_init
of_find_matching_node() returns a node pointer with refcount
incremented, we should use of_node_put() on it when not need anymore.
Add missing of_node_put() to avoid refcount leak.
In the Linux kernel, the following vulnerability has been resolved:
mtd: maps: Fix refcount leak in of_flash_probe_versatile
of_find_matching_node_and_match() returns a node pointer with refcount
incremented, we should use of_node_put() on it when not need anymore.
Add missing of_node_put() to avoid refcount leak.
In the Linux kernel, the following vulnerability has been resolved:
wifi: libertas: Fix possible refcount leak in if_usb_probe()
usb_get_dev will be called before lbs_get_firmware_async which means that
usb_put_dev need to be called when lbs_get_firmware_async fails.
In the Linux kernel, the following vulnerability has been resolved:
wifi: wil6210: debugfs: fix uninitialized variable use in `wil_write_file_wmi()`
Commit 7a4836560a61 changes simple_write_to_buffer() with memdup_user()
but it forgets to change the value to be returned that came from
simple_write_to_buffer() call. It results in the following warning:
warning: variable 'rc' is uninitialized when used here [-Wuninitialized]
return rc;
^~
Remove rc variable and just return the passed in length if the
memdup_user() succeeds.
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: When HCI work queue is drained, only queue chained work
The HCI command, event, and data packet processing workqueue is drained
to avoid deadlock in commit
76727c02c1e1 ("Bluetooth: Call drain_workqueue() before resetting state").
There is another delayed work, which will queue command to this drained
workqueue. Which results in the following error report:
Bluetooth: hci2: command 0x040f tx timeout
WARNING: CPU: 1 PID: 18374 at kernel/workqueue.c:1438 __queue_work+0xdad/0x1140
Workqueue: events hci_cmd_timeout
RIP: 0010:__queue_work+0xdad/0x1140
RSP: 0000:ffffc90002cffc60 EFLAGS: 00010093
RAX: 0000000000000000 RBX: ffff8880b9d3ec00 RCX: 0000000000000000
RDX: ffff888024ba0000 RSI: ffffffff814e048d RDI: ffff8880b9d3ec08
RBP: 0000000000000008 R08: 0000000000000000 R09: 00000000b9d39700
R10: ffffffff814f73c6 R11: 0000000000000000 R12: ffff88807cce4c60
R13: 0000000000000000 R14: ffff8880796d8800 R15: ffff8880796d8800
FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c0174b4000 CR3: 000000007cae9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
? queue_work_on+0xcb/0x110
? lockdep_hardirqs_off+0x90/0xd0
queue_work_on+0xee/0x110
process_one_work+0x996/0x1610
? pwq_dec_nr_in_flight+0x2a0/0x2a0
? rwlock_bug.part.0+0x90/0x90
? _raw_spin_lock_irq+0x41/0x50
worker_thread+0x665/0x1080
? process_one_work+0x1610/0x1610
kthread+0x2e9/0x3a0
? kthread_complete_and_exit+0x40/0x40
ret_from_fork+0x1f/0x30
</TASK>
To fix this, we can add a new HCI_DRAIN_WQ flag, and don't queue the
timeout workqueue while command workqueue is draining.
In the Linux kernel, the following vulnerability has been resolved:
usb: ohci-nxp: Fix refcount leak in ohci_hcd_nxp_probe
of_parse_phandle() returns a node pointer with refcount
incremented, we should use of_node_put() on it when not need anymore.
Add missing of_node_put() to avoid refcount leak.
In the Linux kernel, the following vulnerability has been resolved:
usb: host: Fix refcount leak in ehci_hcd_ppc_of_probe
of_find_compatible_node() returns a node pointer with refcount
incremented, we should use of_node_put() on it when done.
Add missing of_node_put() to avoid refcount leak.