| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: don't drop extent_map for free space inode on write error
While running the CI for an unrelated change I hit the following panic
with generic/648 on btrfs_holes_spacecache.
assertion failed: block_start != EXTENT_MAP_HOLE, in fs/btrfs/extent_io.c:1385
------------[ cut here ]------------
kernel BUG at fs/btrfs/extent_io.c:1385!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 2695096 Comm: fsstress Kdump: loaded Tainted: G W 6.8.0-rc2+ #1
RIP: 0010:__extent_writepage_io.constprop.0+0x4c1/0x5c0
Call Trace:
<TASK>
extent_write_cache_pages+0x2ac/0x8f0
extent_writepages+0x87/0x110
do_writepages+0xd5/0x1f0
filemap_fdatawrite_wbc+0x63/0x90
__filemap_fdatawrite_range+0x5c/0x80
btrfs_fdatawrite_range+0x1f/0x50
btrfs_write_out_cache+0x507/0x560
btrfs_write_dirty_block_groups+0x32a/0x420
commit_cowonly_roots+0x21b/0x290
btrfs_commit_transaction+0x813/0x1360
btrfs_sync_file+0x51a/0x640
__x64_sys_fdatasync+0x52/0x90
do_syscall_64+0x9c/0x190
entry_SYSCALL_64_after_hwframe+0x6e/0x76
This happens because we fail to write out the free space cache in one
instance, come back around and attempt to write it again. However on
the second pass through we go to call btrfs_get_extent() on the inode to
get the extent mapping. Because this is a new block group, and with the
free space inode we always search the commit root to avoid deadlocking
with the tree, we find nothing and return a EXTENT_MAP_HOLE for the
requested range.
This happens because the first time we try to write the space cache out
we hit an error, and on an error we drop the extent mapping. This is
normal for normal files, but the free space cache inode is special. We
always expect the extent map to be correct. Thus the second time
through we end up with a bogus extent map.
Since we're deprecating this feature, the most straightforward way to
fix this is to simply skip dropping the extent map range for this failed
range.
I shortened the test by using error injection to stress the area to make
it easier to reproduce. With this patch in place we no longer panic
with my error injection test. |
| In the Linux kernel, the following vulnerability has been resolved:
parisc: Fix random data corruption from exception handler
The current exception handler implementation, which assists when accessing
user space memory, may exhibit random data corruption if the compiler decides
to use a different register than the specified register %r29 (defined in
ASM_EXCEPTIONTABLE_REG) for the error code. If the compiler choose another
register, the fault handler will nevertheless store -EFAULT into %r29 and thus
trash whatever this register is used for.
Looking at the assembly I found that this happens sometimes in emulate_ldd().
To solve the issue, the easiest solution would be if it somehow is
possible to tell the fault handler which register is used to hold the error
code. Using %0 or %1 in the inline assembly is not posssible as it will show
up as e.g. %r29 (with the "%r" prefix), which the GNU assembler can not
convert to an integer.
This patch takes another, better and more flexible approach:
We extend the __ex_table (which is out of the execution path) by one 32-word.
In this word we tell the compiler to insert the assembler instruction
"or %r0,%r0,%reg", where %reg references the register which the compiler
choosed for the error return code.
In case of an access failure, the fault handler finds the __ex_table entry and
can examine the opcode. The used register is encoded in the lowest 5 bits, and
the fault handler can then store -EFAULT into this register.
Since we extend the __ex_table to 3 words we can't use the BUILDTIME_TABLE_SORT
config option any longer. |
| In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix data corruption in dsync block recovery for small block sizes
The helper function nilfs_recovery_copy_block() of
nilfs_recovery_dsync_blocks(), which recovers data from logs created by
data sync writes during a mount after an unclean shutdown, incorrectly
calculates the on-page offset when copying repair data to the file's page
cache. In environments where the block size is smaller than the page
size, this flaw can cause data corruption and leak uninitialized memory
bytes during the recovery process.
Fix these issues by correcting this byte offset calculation on the page. |
| In the Linux kernel, the following vulnerability has been resolved:
tty: n_gsm: require CAP_NET_ADMIN to attach N_GSM0710 ldisc
Any unprivileged user can attach N_GSM0710 ldisc, but it requires
CAP_NET_ADMIN to create a GSM network anyway.
Require initial namespace CAP_NET_ADMIN to do that. |
| In the Linux kernel, the following vulnerability has been resolved:
locking/ww_mutex/test: Fix potential workqueue corruption
In some cases running with the test-ww_mutex code, I was seeing
odd behavior where sometimes it seemed flush_workqueue was
returning before all the work threads were finished.
Often this would cause strange crashes as the mutexes would be
freed while they were being used.
Looking at the code, there is a lifetime problem as the
controlling thread that spawns the work allocates the
"struct stress" structures that are passed to the workqueue
threads. Then when the workqueue threads are finished,
they free the stress struct that was passed to them.
Unfortunately the workqueue work_struct node is in the stress
struct. Which means the work_struct is freed before the work
thread returns and while flush_workqueue is waiting.
It seems like a better idea to have the controlling thread
both allocate and free the stress structures, so that we can
be sure we don't corrupt the workqueue by freeing the structure
prematurely.
So this patch reworks the test to do so, and with this change
I no longer see the early flush_workqueue returns. |
| In the Linux kernel, the following vulnerability has been resolved:
cpu/hotplug: Don't offline the last non-isolated CPU
If a system has isolated CPUs via the "isolcpus=" command line parameter,
then an attempt to offline the last housekeeping CPU will result in a
WARN_ON() when rebuilding the scheduler domains and a subsequent panic due
to and unhandled empty CPU mas in partition_sched_domains_locked().
cpuset_hotplug_workfn()
rebuild_sched_domains_locked()
ndoms = generate_sched_domains(&doms, &attr);
cpumask_and(doms[0], top_cpuset.effective_cpus, housekeeping_cpumask(HK_FLAG_DOMAIN));
Thus results in an empty CPU mask which triggers the warning and then the
subsequent crash:
WARNING: CPU: 4 PID: 80 at kernel/sched/topology.c:2366 build_sched_domains+0x120c/0x1408
Call trace:
build_sched_domains+0x120c/0x1408
partition_sched_domains_locked+0x234/0x880
rebuild_sched_domains_locked+0x37c/0x798
rebuild_sched_domains+0x30/0x58
cpuset_hotplug_workfn+0x2a8/0x930
Unable to handle kernel paging request at virtual address fffe80027ab37080
partition_sched_domains_locked+0x318/0x880
rebuild_sched_domains_locked+0x37c/0x798
Aside of the resulting crash, it does not make any sense to offline the last
last housekeeping CPU.
Prevent this by masking out the non-housekeeping CPUs when selecting a
target CPU for initiating the CPU unplug operation via the work queue. |
| In the Linux kernel, the following vulnerability has been resolved:
media: imon: fix access to invalid resource for the second interface
imon driver probes two USB interfaces, and at the probe of the second
interface, the driver assumes blindly that the first interface got
bound with the same imon driver. It's usually true, but it's still
possible that the first interface is bound with another driver via a
malformed descriptor. Then it may lead to a memory corruption, as
spotted by syzkaller; imon driver accesses the data from drvdata as
struct imon_context object although it's a completely different one
that was assigned by another driver.
This patch adds a sanity check -- whether the first interface is
really bound with the imon driver or not -- for avoiding the problem
above at the probe time. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: disallow timeout for anonymous sets
Never used from userspace, disallow these parameters. |
| In the Linux kernel, the following vulnerability has been resolved:
pstore/ram: Fix crash when setting number of cpus to an odd number
When the number of cpu cores is adjusted to 7 or other odd numbers,
the zone size will become an odd number.
The address of the zone will become:
addr of zone0 = BASE
addr of zone1 = BASE + zone_size
addr of zone2 = BASE + zone_size*2
...
The address of zone1/3/5/7 will be mapped to non-alignment va.
Eventually crashes will occur when accessing these va.
So, use ALIGN_DOWN() to make sure the zone size is even
to avoid this bug. |
| In the Linux kernel, the following vulnerability has been resolved:
dm: fix unconditional IO throttle caused by REQ_PREFLUSH
When a bio with REQ_PREFLUSH is submitted to dm, __send_empty_flush()
generates a flush_bio with REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC,
which causes the flush_bio to be throttled by wbt_wait().
An example from v5.4, similar problem also exists in upstream:
crash> bt 2091206
PID: 2091206 TASK: ffff2050df92a300 CPU: 109 COMMAND: "kworker/u260:0"
#0 [ffff800084a2f7f0] __switch_to at ffff80004008aeb8
#1 [ffff800084a2f820] __schedule at ffff800040bfa0c4
#2 [ffff800084a2f880] schedule at ffff800040bfa4b4
#3 [ffff800084a2f8a0] io_schedule at ffff800040bfa9c4
#4 [ffff800084a2f8c0] rq_qos_wait at ffff8000405925bc
#5 [ffff800084a2f940] wbt_wait at ffff8000405bb3a0
#6 [ffff800084a2f9a0] __rq_qos_throttle at ffff800040592254
#7 [ffff800084a2f9c0] blk_mq_make_request at ffff80004057cf38
#8 [ffff800084a2fa60] generic_make_request at ffff800040570138
#9 [ffff800084a2fae0] submit_bio at ffff8000405703b4
#10 [ffff800084a2fb50] xlog_write_iclog at ffff800001280834 [xfs]
#11 [ffff800084a2fbb0] xlog_sync at ffff800001280c3c [xfs]
#12 [ffff800084a2fbf0] xlog_state_release_iclog at ffff800001280df4 [xfs]
#13 [ffff800084a2fc10] xlog_write at ffff80000128203c [xfs]
#14 [ffff800084a2fcd0] xlog_cil_push at ffff8000012846dc [xfs]
#15 [ffff800084a2fda0] xlog_cil_push_work at ffff800001284a2c [xfs]
#16 [ffff800084a2fdb0] process_one_work at ffff800040111d08
#17 [ffff800084a2fe00] worker_thread at ffff8000401121cc
#18 [ffff800084a2fe70] kthread at ffff800040118de4
After commit 2def2845cc33 ("xfs: don't allow log IO to be throttled"),
the metadata submitted by xlog_write_iclog() should not be throttled.
But due to the existence of the dm layer, throttling flush_bio indirectly
causes the metadata bio to be throttled.
Fix this by conditionally adding REQ_IDLE to flush_bio.bi_opf, which makes
wbt_should_throttle() return false to avoid wbt_wait(). |
| In the Linux kernel, the following vulnerability has been resolved:
media: cx231xx: set device_caps for 417
The video_device for the MPEG encoder did not set device_caps.
Add this, otherwise the video device can't be registered (you get a
WARN_ON instead).
Not seen before since currently 417 support is disabled, but I found
this while experimenting with it. |
| In the Linux kernel, the following vulnerability has been resolved:
dm: call the resume method on internal suspend
There is this reported crash when experimenting with the lvm2 testsuite.
The list corruption is caused by the fact that the postsuspend and resume
methods were not paired correctly; there were two consecutive calls to the
origin_postsuspend function. The second call attempts to remove the
"hash_list" entry from a list, while it was already removed by the first
call.
Fix __dm_internal_resume so that it calls the preresume and resume
methods of the table's targets.
If a preresume method of some target fails, we are in a tricky situation.
We can't return an error because dm_internal_resume isn't supposed to
return errors. We can't return success, because then the "resume" and
"postsuspend" methods would not be paired correctly. So, we set the
DMF_SUSPENDED flag and we fake normal suspend - it may confuse userspace
tools, but it won't cause a kernel crash.
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:56!
invalid opcode: 0000 [#1] PREEMPT SMP
CPU: 1 PID: 8343 Comm: dmsetup Not tainted 6.8.0-rc6 #4
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
RIP: 0010:__list_del_entry_valid_or_report+0x77/0xc0
<snip>
RSP: 0018:ffff8881b831bcc0 EFLAGS: 00010282
RAX: 000000000000004e RBX: ffff888143b6eb80 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff819053d0 RDI: 00000000ffffffff
RBP: ffff8881b83a3400 R08: 00000000fffeffff R09: 0000000000000058
R10: 0000000000000000 R11: ffffffff81a24080 R12: 0000000000000001
R13: ffff88814538e000 R14: ffff888143bc6dc0 R15: ffffffffa02e4bb0
FS: 00000000f7c0f780(0000) GS:ffff8893f0a40000(0000) knlGS:0000000000000000
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000057fb5000 CR3: 0000000143474000 CR4: 00000000000006b0
Call Trace:
<TASK>
? die+0x2d/0x80
? do_trap+0xeb/0xf0
? __list_del_entry_valid_or_report+0x77/0xc0
? do_error_trap+0x60/0x80
? __list_del_entry_valid_or_report+0x77/0xc0
? exc_invalid_op+0x49/0x60
? __list_del_entry_valid_or_report+0x77/0xc0
? asm_exc_invalid_op+0x16/0x20
? table_deps+0x1b0/0x1b0 [dm_mod]
? __list_del_entry_valid_or_report+0x77/0xc0
origin_postsuspend+0x1a/0x50 [dm_snapshot]
dm_table_postsuspend_targets+0x34/0x50 [dm_mod]
dm_suspend+0xd8/0xf0 [dm_mod]
dev_suspend+0x1f2/0x2f0 [dm_mod]
? table_deps+0x1b0/0x1b0 [dm_mod]
ctl_ioctl+0x300/0x5f0 [dm_mod]
dm_compat_ctl_ioctl+0x7/0x10 [dm_mod]
__x64_compat_sys_ioctl+0x104/0x170
do_syscall_64+0x184/0x1b0
entry_SYSCALL_64_after_hwframe+0x46/0x4e
RIP: 0033:0xf7e6aead
<snip>
---[ end trace 0000000000000000 ]--- |
| In the Linux kernel, the following vulnerability has been resolved:
md/bitmap: don't set sb values if can't pass sanity check
If bitmap area contains invalid data, kernel will crash then mdadm
triggers "Segmentation fault".
This is cluster-md speical bug. In non-clustered env, mdadm will
handle broken metadata case. In clustered array, only kernel space
handles bitmap slot info. But even this bug only happened in clustered
env, current sanity check is wrong, the code should be changed.
How to trigger: (faulty injection)
dd if=/dev/zero bs=1M count=1 oflag=direct of=/dev/sda
dd if=/dev/zero bs=1M count=1 oflag=direct of=/dev/sdb
mdadm -C /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda /dev/sdb
mdadm -Ss
echo aaa > magic.txt
== below modifying slot 2 bitmap data ==
dd if=magic.txt of=/dev/sda seek=16384 bs=1 count=3 <== destroy magic
dd if=/dev/zero of=/dev/sda seek=16436 bs=1 count=4 <== ZERO chunksize
mdadm -A /dev/md0 /dev/sda /dev/sdb
== kernel crashes. mdadm outputs "Segmentation fault" ==
Reason of kernel crash:
In md_bitmap_read_sb (called by md_bitmap_create), bad bitmap magic didn't
block chunksize assignment, and zero value made DIV_ROUND_UP_SECTOR_T()
trigger "divide error".
Crash log:
kernel: md: md0 stopped.
kernel: md/raid1:md0: not clean -- starting background reconstruction
kernel: md/raid1:md0: active with 2 out of 2 mirrors
kernel: dlm: ... ...
kernel: md-cluster: Joined cluster 44810aba-38bb-e6b8-daca-bc97a0b254aa slot 1
kernel: md0: invalid bitmap file superblock: bad magic
kernel: md_bitmap_copy_from_slot can't get bitmap from slot 2
kernel: md-cluster: Could not gather bitmaps from slot 2
kernel: divide error: 0000 [#1] SMP NOPTI
kernel: CPU: 0 PID: 1603 Comm: mdadm Not tainted 5.14.6-1-default
kernel: Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
kernel: RIP: 0010:md_bitmap_create+0x1d1/0x850 [md_mod]
kernel: RSP: 0018:ffffc22ac0843ba0 EFLAGS: 00010246
kernel: ... ...
kernel: Call Trace:
kernel: ? dlm_lock_sync+0xd0/0xd0 [md_cluster 77fe..7a0]
kernel: md_bitmap_copy_from_slot+0x2c/0x290 [md_mod 24ea..d3a]
kernel: load_bitmaps+0xec/0x210 [md_cluster 77fe..7a0]
kernel: md_bitmap_load+0x81/0x1e0 [md_mod 24ea..d3a]
kernel: do_md_run+0x30/0x100 [md_mod 24ea..d3a]
kernel: md_ioctl+0x1290/0x15a0 [md_mod 24ea....d3a]
kernel: ? mddev_unlock+0xaa/0x130 [md_mod 24ea..d3a]
kernel: ? blkdev_ioctl+0xb1/0x2b0
kernel: block_ioctl+0x3b/0x40
kernel: __x64_sys_ioctl+0x7f/0xb0
kernel: do_syscall_64+0x59/0x80
kernel: ? exit_to_user_mode_prepare+0x1ab/0x230
kernel: ? syscall_exit_to_user_mode+0x18/0x40
kernel: ? do_syscall_64+0x69/0x80
kernel: entry_SYSCALL_64_after_hwframe+0x44/0xae
kernel: RIP: 0033:0x7f4a15fa722b
kernel: ... ...
kernel: ---[ end trace 8afa7612f559c868 ]---
kernel: RIP: 0010:md_bitmap_create+0x1d1/0x850 [md_mod] |
| In the Linux kernel, the following vulnerability has been resolved:
tcp: add accessors to read/set tp->snd_cwnd
We had various bugs over the years with code
breaking the assumption that tp->snd_cwnd is greater
than zero.
Lately, syzbot reported the WARN_ON_ONCE(!tp->prior_cwnd) added
in commit 8b8a321ff72c ("tcp: fix zero cwnd in tcp_cwnd_reduction")
can trigger, and without a repro we would have to spend
considerable time finding the bug.
Instead of complaining too late, we want to catch where
and when tp->snd_cwnd is set to an illegal value. |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: don't BUG if someone dirty pages without asking ext4 first
[un]pin_user_pages_remote is dirtying pages without properly warning
the file system in advance. A related race was noted by Jan Kara in
2018[1]; however, more recently instead of it being a very hard-to-hit
race, it could be reliably triggered by process_vm_writev(2) which was
discovered by Syzbot[2].
This is technically a bug in mm/gup.c, but arguably ext4 is fragile in
that if some other kernel subsystem dirty pages without properly
notifying the file system using page_mkwrite(), ext4 will BUG, while
other file systems will not BUG (although data will still be lost).
So instead of crashing with a BUG, issue a warning (since there may be
potential data loss) and just mark the page as clean to avoid
unprivileged denial of service attacks until the problem can be
properly fixed. More discussion and background can be found in the
thread starting at [2].
[1] https://lore.kernel.org/linux-mm/20180103100430.GE4911@quack2.suse.cz
[2] https://lore.kernel.org/r/Yg0m6IjcNmfaSokM@google.com |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Fix scheduling while atomic
The driver makes a call into midlayer (fc_remote_port_delete) which can put
the thread to sleep. The thread that originates the call is in interrupt
context. The combination of the two trigger a crash. Schedule the call in
non-interrupt context where it is more safe.
kernel: BUG: scheduling while atomic: swapper/7/0/0x00010000
kernel: Call Trace:
kernel: <IRQ>
kernel: dump_stack+0x66/0x81
kernel: __schedule_bug.cold.90+0x5/0x1d
kernel: __schedule+0x7af/0x960
kernel: schedule+0x28/0x80
kernel: schedule_timeout+0x26d/0x3b0
kernel: wait_for_completion+0xb4/0x140
kernel: ? wake_up_q+0x70/0x70
kernel: __wait_rcu_gp+0x12c/0x160
kernel: ? sdev_evt_alloc+0xc0/0x180 [scsi_mod]
kernel: synchronize_sched+0x6c/0x80
kernel: ? call_rcu_bh+0x20/0x20
kernel: ? __bpf_trace_rcu_invoke_callback+0x10/0x10
kernel: sdev_evt_alloc+0xfd/0x180 [scsi_mod]
kernel: starget_for_each_device+0x85/0xb0 [scsi_mod]
kernel: ? scsi_init_io+0x360/0x3d0 [scsi_mod]
kernel: scsi_init_io+0x388/0x3d0 [scsi_mod]
kernel: device_for_each_child+0x54/0x90
kernel: fc_remote_port_delete+0x70/0xe0 [scsi_transport_fc]
kernel: qla2x00_schedule_rport_del+0x62/0xf0 [qla2xxx]
kernel: qla2x00_mark_device_lost+0x9c/0xd0 [qla2xxx]
kernel: qla24xx_handle_plogi_done_event+0x55f/0x570 [qla2xxx]
kernel: qla2x00_async_login_sp_done+0xd2/0x100 [qla2xxx]
kernel: qla24xx_logio_entry+0x13a/0x3c0 [qla2xxx]
kernel: qla24xx_process_response_queue+0x306/0x400 [qla2xxx]
kernel: qla24xx_msix_rsp_q+0x3f/0xb0 [qla2xxx]
kernel: __handle_irq_event_percpu+0x40/0x180
kernel: handle_irq_event_percpu+0x30/0x80
kernel: handle_irq_event+0x36/0x60 |
| In the Linux kernel, the following vulnerability has been resolved:
x86/mce: Work around an erratum on fast string copy instructions
A rare kernel panic scenario can happen when the following conditions
are met due to an erratum on fast string copy instructions:
1) An uncorrected error.
2) That error must be in first cache line of a page.
3) Kernel must execute page_copy from the page immediately before that
page.
The fast string copy instructions ("REP; MOVS*") could consume an
uncorrectable memory error in the cache line _right after_ the desired
region to copy and raise an MCE.
Bit 0 of MSR_IA32_MISC_ENABLE can be cleared to disable fast string
copy and will avoid such spurious machine checks. However, that is less
preferable due to the permanent performance impact. Considering memory
poison is rare, it's desirable to keep fast string copy enabled until an
MCE is seen.
Intel has confirmed the following:
1. The CPU erratum of fast string copy only applies to Skylake,
Cascade Lake and Cooper Lake generations.
Directly return from the MCE handler:
2. Will result in complete execution of the "REP; MOVS*" with no data
loss or corruption.
3. Will not result in another MCE firing on the next poisoned cache line
due to "REP; MOVS*".
4. Will resume execution from a correct point in code.
5. Will result in the same instruction that triggered the MCE firing a
second MCE immediately for any other software recoverable data fetch
errors.
6. Is not safe without disabling the fast string copy, as the next fast
string copy of the same buffer on the same CPU would result in a PANIC
MCE.
This should mitigate the erratum completely with the only caveat that
the fast string copy is disabled on the affected hyper thread thus
performance degradation.
This is still better than the OS crashing on MCEs raised on an
irrelevant process due to "REP; MOVS*' accesses in a kernel context,
e.g., copy_page.
Injected errors on 1st cache line of 8 anonymous pages of process
'proc1' and observed MCE consumption from 'proc2' with no panic
(directly returned).
Without the fix, the host panicked within a few minutes on a
random 'proc2' process due to kernel access from copy_page.
[ bp: Fix comment style + touch ups, zap an unlikely(), improve the
quirk function's readability. ] |
| In the Linux kernel, the following vulnerability has been resolved:
regulator: da9211: Use irq handler when ready
If the system does not come from reset (like when it is kexec()), the
regulator might have an IRQ waiting for us.
If we enable the IRQ handler before its structures are ready, we crash.
This patch fixes:
[ 1.141839] Unable to handle kernel read from unreadable memory at virtual address 0000000000000078
[ 1.316096] Call trace:
[ 1.316101] blocking_notifier_call_chain+0x20/0xa8
[ 1.322757] cpu cpu0: dummy supplies not allowed for exclusive requests
[ 1.327823] regulator_notifier_call_chain+0x1c/0x2c
[ 1.327825] da9211_irq_handler+0x68/0xf8
[ 1.327829] irq_thread+0x11c/0x234
[ 1.327833] kthread+0x13c/0x154 |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: LAPIC: Also cancel preemption timer during SET_LAPIC
The below warning is splatting during guest reboot.
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1931 at arch/x86/kvm/x86.c:10322 kvm_arch_vcpu_ioctl_run+0x874/0x880 [kvm]
CPU: 0 PID: 1931 Comm: qemu-system-x86 Tainted: G I 5.17.0-rc1+ #5
RIP: 0010:kvm_arch_vcpu_ioctl_run+0x874/0x880 [kvm]
Call Trace:
<TASK>
kvm_vcpu_ioctl+0x279/0x710 [kvm]
__x64_sys_ioctl+0x83/0xb0
do_syscall_64+0x3b/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fd39797350b
This can be triggered by not exposing tsc-deadline mode and doing a reboot in
the guest. The lapic_shutdown() function which is called in sys_reboot path
will not disarm the flying timer, it just masks LVTT. lapic_shutdown() clears
APIC state w/ LVT_MASKED and timer-mode bit is 0, this can trigger timer-mode
switch between tsc-deadline and oneshot/periodic, which can result in preemption
timer be cancelled in apic_update_lvtt(). However, We can't depend on this when
not exposing tsc-deadline mode and oneshot/periodic modes emulated by preemption
timer. Qemu will synchronise states around reset, let's cancel preemption timer
under KVM_SET_LAPIC. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Fix circular locking dependency
The rule inside kvm enforces that the vcpu->mutex is taken *inside*
kvm->lock. The rule is violated by the pkvm_create_hyp_vm() which acquires
the kvm->lock while already holding the vcpu->mutex lock from
kvm_vcpu_ioctl(). Avoid the circular locking dependency altogether by
protecting the hyp vm handle with the config_lock, much like we already
do for other forms of VM-scoped data. |
