Security Vulnerabilities - CVEs Published In May 2024
In the Linux kernel, the following vulnerability has been resolved:
blk-mq: cancel blk-mq dispatch work in both blk_cleanup_queue and disk_release()
For avoiding to slow down queue destroy, we don't call
blk_mq_quiesce_queue() in blk_cleanup_queue(), instead of delaying to
cancel dispatch work in blk_release_queue().
However, this way has caused kernel oops[1], reported by Changhui. The log
shows that scsi_device can be freed before running blk_release_queue(),
which is expected too since scsi_device is released after the scsi disk
is closed and the scsi_device is removed.
Fixes the issue by canceling blk-mq dispatch work in both blk_cleanup_queue()
and disk_release():
1) when disk_release() is run, the disk has been closed, and any sync
dispatch activities have been done, so canceling dispatch work is enough to
quiesce filesystem I/O dispatch activity.
2) in blk_cleanup_queue(), we only focus on passthrough request, and
passthrough request is always explicitly allocated & freed by
its caller, so once queue is frozen, all sync dispatch activity
for passthrough request has been done, then it is enough to just cancel
dispatch work for avoiding any dispatch activity.
[1] kernel panic log
[12622.769416] BUG: kernel NULL pointer dereference, address: 0000000000000300
[12622.777186] #PF: supervisor read access in kernel mode
[12622.782918] #PF: error_code(0x0000) - not-present page
[12622.788649] PGD 0 P4D 0
[12622.791474] Oops: 0000 [#1] PREEMPT SMP PTI
[12622.796138] CPU: 10 PID: 744 Comm: kworker/10:1H Kdump: loaded Not tainted 5.15.0+ #1
[12622.804877] Hardware name: Dell Inc. PowerEdge R730/0H21J3, BIOS 1.5.4 10/002/2015
[12622.813321] Workqueue: kblockd blk_mq_run_work_fn
[12622.818572] RIP: 0010:sbitmap_get+0x75/0x190
[12622.823336] Code: 85 80 00 00 00 41 8b 57 08 85 d2 0f 84 b1 00 00 00 45 31 e4 48 63 cd 48 8d 1c 49 48 c1 e3 06 49 03 5f 10 4c 8d 6b 40 83 f0 01 <48> 8b 33 44 89 f2 4c 89 ef 0f b6 c8 e8 fa f3 ff ff 83 f8 ff 75 58
[12622.844290] RSP: 0018:ffffb00a446dbd40 EFLAGS: 00010202
[12622.850120] RAX: 0000000000000001 RBX: 0000000000000300 RCX: 0000000000000004
[12622.858082] RDX: 0000000000000006 RSI: 0000000000000082 RDI: ffffa0b7a2dfe030
[12622.866042] RBP: 0000000000000004 R08: 0000000000000001 R09: ffffa0b742721334
[12622.874003] R10: 0000000000000008 R11: 0000000000000008 R12: 0000000000000000
[12622.881964] R13: 0000000000000340 R14: 0000000000000000 R15: ffffa0b7a2dfe030
[12622.889926] FS: 0000000000000000(0000) GS:ffffa0baafb40000(0000) knlGS:0000000000000000
[12622.898956] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[12622.905367] CR2: 0000000000000300 CR3: 0000000641210001 CR4: 00000000001706e0
[12622.913328] Call Trace:
[12622.916055] <TASK>
[12622.918394] scsi_mq_get_budget+0x1a/0x110
[12622.922969] __blk_mq_do_dispatch_sched+0x1d4/0x320
[12622.928404] ? pick_next_task_fair+0x39/0x390
[12622.933268] __blk_mq_sched_dispatch_requests+0xf4/0x140
[12622.939194] blk_mq_sched_dispatch_requests+0x30/0x60
[12622.944829] __blk_mq_run_hw_queue+0x30/0xa0
[12622.949593] process_one_work+0x1e8/0x3c0
[12622.954059] worker_thread+0x50/0x3b0
[12622.958144] ? rescuer_thread+0x370/0x370
[12622.962616] kthread+0x158/0x180
[12622.966218] ? set_kthread_struct+0x40/0x40
[12622.970884] ret_from_fork+0x22/0x30
[12622.974875] </TASK>
[12622.977309] Modules linked in: scsi_debug rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs sunrpc dm_multipath intel_rapl_msr intel_rapl_common dell_wmi_descriptor sb_edac rfkill video x86_pkg_temp_thermal intel_powerclamp dcdbas coretemp kvm_intel kvm mgag200 irqbypass i2c_algo_bit rapl drm_kms_helper ipmi_ssif intel_cstate intel_uncore syscopyarea sysfillrect sysimgblt fb_sys_fops pcspkr cec mei_me lpc_ich mei ipmi_si ipmi_devintf ipmi_msghandler acpi_power_meter drm fuse xfs libcrc32c sr_mod cdrom sd_mod t10_pi sg ixgbe ahci libahci crct10dif_pclmul crc32_pclmul crc32c_intel libata megaraid_sas ghash_clmulni_intel tg3 wdat_w
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
sched/scs: Reset task stack state in bringup_cpu()
To hot unplug a CPU, the idle task on that CPU calls a few layers of C
code before finally leaving the kernel. When KASAN is in use, poisoned
shadow is left around for each of the active stack frames, and when
shadow call stacks are in use. When shadow call stacks (SCS) are in use
the task's saved SCS SP is left pointing at an arbitrary point within
the task's shadow call stack.
When a CPU is offlined than onlined back into the kernel, this stale
state can adversely affect execution. Stale KASAN shadow can alias new
stackframes and result in bogus KASAN warnings. A stale SCS SP is
effectively a memory leak, and prevents a portion of the shadow call
stack being used. Across a number of hotplug cycles the idle task's
entire shadow call stack can become unusable.
We previously fixed the KASAN issue in commit:
e1b77c92981a5222 ("sched/kasan: remove stale KASAN poison after hotplug")
... by removing any stale KASAN stack poison immediately prior to
onlining a CPU.
Subsequently in commit:
f1a0a376ca0c4ef1 ("sched/core: Initialize the idle task with preemption disabled")
... the refactoring left the KASAN and SCS cleanup in one-time idle
thread initialization code rather than something invoked prior to each
CPU being onlined, breaking both as above.
We fixed SCS (but not KASAN) in commit:
63acd42c0d4942f7 ("sched/scs: Reset the shadow stack when idle_task_exit")
... but as this runs in the context of the idle task being offlined it's
potentially fragile.
To fix these consistently and more robustly, reset the SCS SP and KASAN
shadow of a CPU's idle task immediately before we online that CPU in
bringup_cpu(). This ensures the idle task always has a consistent state
when it is running, and removes the need to so so when exiting an idle
task.
Whenever any thread is created, dup_task_struct() will give the task a
stack which is free of KASAN shadow, and initialize the task's SCS SP,
so there's no need to specially initialize either for idle thread within
init_idle(), as this was only necessary to handle hotplug cycles.
I've tested this on arm64 with:
* gcc 11.1.0, defconfig +KASAN_INLINE, KASAN_STACK
* clang 12.0.0, defconfig +KASAN_INLINE, KASAN_STACK, SHADOW_CALL_STACK
... offlining and onlining CPUS with:
| while true; do
| for C in /sys/devices/system/cpu/cpu*/online; do
| echo 0 > $C;
| echo 1 > $C;
| done
| done
CVSS Score
7.8
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
vdpa_sim: avoid putting an uninitialized iova_domain
The system will crash if we put an uninitialized iova_domain, this
could happen when an error occurs before initializing the iova_domain
in vdpasim_create().
BUG: kernel NULL pointer dereference, address: 0000000000000000
...
RIP: 0010:__cpuhp_state_remove_instance+0x96/0x1c0
...
Call Trace:
<TASK>
put_iova_domain+0x29/0x220
vdpasim_free+0xd1/0x120 [vdpa_sim]
vdpa_release_dev+0x21/0x40 [vdpa]
device_release+0x33/0x90
kobject_release+0x63/0x160
vdpasim_create+0x127/0x2a0 [vdpa_sim]
vdpasim_net_dev_add+0x7d/0xfe [vdpa_sim_net]
vdpa_nl_cmd_dev_add_set_doit+0xe1/0x1a0 [vdpa]
genl_family_rcv_msg_doit+0x112/0x140
genl_rcv_msg+0xdf/0x1d0
...
So we must make sure the iova_domain is already initialized before
put it.
In addition, we may get the following warning in this case:
WARNING: ... drivers/iommu/iova.c:344 iova_cache_put+0x58/0x70
So we must make sure the iova_cache_put() is invoked only if the
iova_cache_get() is already invoked. Let's fix it together.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
net: vlan: fix underflow for the real_dev refcnt
Inject error before dev_hold(real_dev) in register_vlan_dev(),
and execute the following testcase:
ip link add dev dummy1 type dummy
ip link add name dummy1.100 link dummy1 type vlan id 100
ip link del dev dummy1
When the dummy netdevice is removed, we will get a WARNING as following:
=======================================================================
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 2 PID: 0 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0
and an endless loop of:
=======================================================================
unregister_netdevice: waiting for dummy1 to become free. Usage count = -1073741824
That is because dev_put(real_dev) in vlan_dev_free() be called without
dev_hold(real_dev) in register_vlan_dev(). It makes the refcnt of real_dev
underflow.
Move the dev_hold(real_dev) to vlan_dev_init() which is the call-back of
ndo_init(). That makes dev_hold() and dev_put() for vlan's real_dev
symmetrical.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
ethtool: ioctl: fix potential NULL deref in ethtool_set_coalesce()
ethtool_set_coalesce() now uses both the .get_coalesce() and
.set_coalesce() callbacks. But the check for their availability is
buggy, so changing the coalesce settings on a device where the driver
provides only _one_ of the callbacks results in a NULL pointer
dereference instead of an -EOPNOTSUPP.
Fix the condition so that the availability of both callbacks is
ensured. This also matches the netlink code.
Note that reproducing this requires some effort - it only affects the
legacy ioctl path, and needs a specific combination of driver options:
- have .get_coalesce() and .coalesce_supported but no
.set_coalesce(), or
- have .set_coalesce() but no .get_coalesce(). Here eg. ethtool doesn't
cause the crash as it first attempts to call ethtool_get_coalesce()
and bails out on error.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
net/sched: sch_ets: don't peek at classes beyond 'nbands'
when the number of DRR classes decreases, the round-robin active list can
contain elements that have already been freed in ets_qdisc_change(). As a
consequence, it's possible to see a NULL dereference crash, caused by the
attempt to call cl->qdisc->ops->peek(cl->qdisc) when cl->qdisc is NULL:
BUG: kernel NULL pointer dereference, address: 0000000000000018
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 910 Comm: mausezahn Not tainted 5.16.0-rc1+ #475
Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014
RIP: 0010:ets_qdisc_dequeue+0x129/0x2c0 [sch_ets]
Code: c5 01 41 39 ad e4 02 00 00 0f 87 18 ff ff ff 49 8b 85 c0 02 00 00 49 39 c4 0f 84 ba 00 00 00 49 8b ad c0 02 00 00 48 8b 7d 10 <48> 8b 47 18 48 8b 40 38 0f ae e8 ff d0 48 89 c3 48 85 c0 0f 84 9d
RSP: 0000:ffffbb36c0b5fdd8 EFLAGS: 00010287
RAX: ffff956678efed30 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff9b938dc9 RDI: 0000000000000000
RBP: ffff956678efed30 R08: e2f3207fe360129c R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: ffff956678efeac0
R13: ffff956678efe800 R14: ffff956611545000 R15: ffff95667ac8f100
FS: 00007f2aa9120740(0000) GS:ffff95667b800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000018 CR3: 000000011070c000 CR4: 0000000000350ee0
Call Trace:
<TASK>
qdisc_peek_dequeued+0x29/0x70 [sch_ets]
tbf_dequeue+0x22/0x260 [sch_tbf]
__qdisc_run+0x7f/0x630
net_tx_action+0x290/0x4c0
__do_softirq+0xee/0x4f8
irq_exit_rcu+0xf4/0x130
sysvec_apic_timer_interrupt+0x52/0xc0
asm_sysvec_apic_timer_interrupt+0x12/0x20
RIP: 0033:0x7f2aa7fc9ad4
Code: b9 ff ff 48 8b 54 24 18 48 83 c4 08 48 89 ee 48 89 df 5b 5d e9 ed fc ff ff 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa <53> 48 83 ec 10 48 8b 05 10 64 33 00 48 8b 00 48 85 c0 0f 85 84 00
RSP: 002b:00007ffe5d33fab8 EFLAGS: 00000202
RAX: 0000000000000002 RBX: 0000561f72c31460 RCX: 0000561f72c31720
RDX: 0000000000000002 RSI: 0000561f72c31722 RDI: 0000561f72c31720
RBP: 000000000000002a R08: 00007ffe5d33fa40 R09: 0000000000000014
R10: 0000000000000000 R11: 0000000000000246 R12: 0000561f7187e380
R13: 0000000000000000 R14: 0000000000000000 R15: 0000561f72c31460
</TASK>
Modules linked in: sch_ets sch_tbf dummy rfkill iTCO_wdt intel_rapl_msr iTCO_vendor_support intel_rapl_common joydev virtio_balloon lpc_ich i2c_i801 i2c_smbus pcspkr ip_tables xfs libcrc32c crct10dif_pclmul crc32_pclmul crc32c_intel ahci libahci ghash_clmulni_intel serio_raw libata virtio_blk virtio_console virtio_net net_failover failover sunrpc dm_mirror dm_region_hash dm_log dm_mod
CR2: 0000000000000018
Ensuring that 'alist' was never zeroed [1] was not sufficient, we need to
remove from the active list those elements that are no more SP nor DRR.
[1] https://lore.kernel.org/netdev/60d274838bf09777f0371253416e8af71360bc08.1633609148.git.dcaratti@redhat.com/
v3: fix race between ets_qdisc_change() and ets_qdisc_dequeue() delisting
DRR classes beyond 'nbands' in ets_qdisc_change() with the qdisc lock
acquired, thanks to Cong Wang.
v2: when a NULL qdisc is found in the DRR active list, try to dequeue skb
from the next list item.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
net: stmmac: Disable Tx queues when reconfiguring the interface
The Tx queues were not disabled in situations where the driver needed to
stop the interface to apply a new configuration. This could result in a
kernel panic when doing any of the 3 following actions:
* reconfiguring the number of queues (ethtool -L)
* reconfiguring the size of the ring buffers (ethtool -G)
* installing/removing an XDP program (ip l set dev ethX xdp)
Prevent the panic by making sure netif_tx_disable is called when stopping
an interface.
Without this patch, the following kernel panic can be observed when doing
any of the actions above:
Unable to handle kernel paging request at virtual address ffff80001238d040
[....]
Call trace:
dwmac4_set_addr+0x8/0x10
dev_hard_start_xmit+0xe4/0x1ac
sch_direct_xmit+0xe8/0x39c
__dev_queue_xmit+0x3ec/0xaf0
dev_queue_xmit+0x14/0x20
[...]
[ end trace 0000000000000002 ]---
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
net/smc: Fix NULL pointer dereferencing in smc_vlan_by_tcpsk()
Coverity reports a possible NULL dereferencing problem:
in smc_vlan_by_tcpsk():
6. returned_null: netdev_lower_get_next returns NULL (checked 29 out of 30 times).
7. var_assigned: Assigning: ndev = NULL return value from netdev_lower_get_next.
1623 ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower);
CID 1468509 (#1 of 1): Dereference null return value (NULL_RETURNS)
8. dereference: Dereferencing a pointer that might be NULL ndev when calling is_vlan_dev.
1624 if (is_vlan_dev(ndev)) {
Remove the manual implementation and use netdev_walk_all_lower_dev() to
iterate over the lower devices. While on it remove an obsolete function
parameter comment.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
mlxsw: spectrum: Protect driver from buggy firmware
When processing port up/down events generated by the device's firmware,
the driver protects itself from events reported for non-existent local
ports, but not the CPU port (local port 0), which exists, but lacks a
netdev.
This can result in a NULL pointer dereference when calling
netif_carrier_{on,off}().
Fix this by bailing early when processing an event reported for the CPU
port. Problem was only observed when running on top of a buggy emulator.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
i2c: virtio: disable timeout handling
If a timeout is hit, it can result is incorrect data on the I2C bus
and/or memory corruptions in the guest since the device can still be
operating on the buffers it was given while the guest has freed them.
Here is, for example, the start of a slub_debug splat which was
triggered on the next transfer after one transfer was forced to timeout
by setting a breakpoint in the backend (rust-vmm/vhost-device):
BUG kmalloc-1k (Not tainted): Poison overwritten
First byte 0x1 instead of 0x6b
Allocated in virtio_i2c_xfer+0x65/0x35c age=350 cpu=0 pid=29
__kmalloc+0xc2/0x1c9
virtio_i2c_xfer+0x65/0x35c
__i2c_transfer+0x429/0x57d
i2c_transfer+0x115/0x134
i2cdev_ioctl_rdwr+0x16a/0x1de
i2cdev_ioctl+0x247/0x2ed
vfs_ioctl+0x21/0x30
sys_ioctl+0xb18/0xb41
Freed in virtio_i2c_xfer+0x32e/0x35c age=244 cpu=0 pid=29
kfree+0x1bd/0x1cc
virtio_i2c_xfer+0x32e/0x35c
__i2c_transfer+0x429/0x57d
i2c_transfer+0x115/0x134
i2cdev_ioctl_rdwr+0x16a/0x1de
i2cdev_ioctl+0x247/0x2ed
vfs_ioctl+0x21/0x30
sys_ioctl+0xb18/0xb41
There is no simple fix for this (the driver would have to always create
bounce buffers and hold on to them until the device eventually returns
the buffers), so just disable the timeout support for now.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-05-24