Linux: >> Linux Kernel >> 6.1.105 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
mctp: route: hold key->lock in mctp_flow_prepare_output()
mctp_flow_prepare_output() checks key->dev and may call
mctp_dev_set_key(), but it does not hold key->lock while doing so.
mctp_dev_set_key() and mctp_dev_release_key() are annotated with
__must_hold(&key->lock), so key->dev access is intended to be
serialized by key->lock. The mctp_sendmsg() transmit path reaches
mctp_flow_prepare_output() via mctp_local_output() -> mctp_dst_output()
without holding key->lock, so the check-and-set sequence is racy.
Example interleaving:
CPU0 CPU1
---- ----
mctp_flow_prepare_output(key, devA)
if (!key->dev) // sees NULL
mctp_flow_prepare_output(
key, devB)
if (!key->dev) // still NULL
mctp_dev_set_key(devB, key)
mctp_dev_hold(devB)
key->dev = devB
mctp_dev_set_key(devA, key)
mctp_dev_hold(devA)
key->dev = devA // overwrites devB
Now both devA and devB references were acquired, but only the final
key->dev value is tracked for release. One reference can be lost,
causing a resource leak as mctp_dev_release_key() would only decrease
the reference on one dev.
Fix by taking key->lock around the key->dev check and
mctp_dev_set_key() call.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
bonding: fix type confusion in bond_setup_by_slave()
kernel BUG at net/core/skbuff.c:2306!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
RIP: 0010:pskb_expand_head+0xa08/0xfe0 net/core/skbuff.c:2306
RSP: 0018:ffffc90004aff760 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff88807e3c8780 RCX: ffffffff89593e0e
RDX: ffff88807b7c4900 RSI: ffffffff89594747 RDI: ffff88807b7c4900
RBP: 0000000000000820 R08: 0000000000000005 R09: 0000000000000000
R10: 00000000961a63e0 R11: 0000000000000000 R12: ffff88807e3c8780
R13: 00000000961a6560 R14: dffffc0000000000 R15: 00000000961a63e0
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe1a0ed8df0 CR3: 000000002d816000 CR4: 00000000003526f0
Call Trace:
<TASK>
ipgre_header+0xdd/0x540 net/ipv4/ip_gre.c:900
dev_hard_header include/linux/netdevice.h:3439 [inline]
packet_snd net/packet/af_packet.c:3028 [inline]
packet_sendmsg+0x3ae5/0x53c0 net/packet/af_packet.c:3108
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa54/0xc30 net/socket.c:2592
___sys_sendmsg+0x190/0x1e0 net/socket.c:2646
__sys_sendmsg+0x170/0x220 net/socket.c:2678
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe1a0e6c1a9
When a non-Ethernet device (e.g. GRE tunnel) is enslaved to a bond,
bond_setup_by_slave() directly copies the slave's header_ops to the
bond device:
bond_dev->header_ops = slave_dev->header_ops;
This causes a type confusion when dev_hard_header() is later called
on the bond device. Functions like ipgre_header(), ip6gre_header(),all use
netdev_priv(dev) to access their device-specific private data. When
called with the bond device, netdev_priv() returns the bond's private
data (struct bonding) instead of the expected type (e.g. struct
ip_tunnel), leading to garbage values being read and kernel crashes.
Fix this by introducing bond_header_ops with wrapper functions that
delegate to the active slave's header_ops using the slave's own
device. This ensures netdev_priv() in the slave's header functions
always receives the correct device.
The fix is placed in the bonding driver rather than individual device
drivers, as the root cause is bond blindly inheriting header_ops from
the slave without considering that these callbacks expect a specific
netdev_priv() layout.
The type confusion can be observed by adding a printk in
ipgre_header() and running the following commands:
ip link add dummy0 type dummy
ip addr add 10.0.0.1/24 dev dummy0
ip link set dummy0 up
ip link add gre1 type gre local 10.0.0.1
ip link add bond1 type bond mode active-backup
ip link set gre1 master bond1
ip link set gre1 up
ip link set bond1 up
ip addr add fe80::1/64 dev bond1
CVSS Score
7.8
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
mctp: i2c: fix skb memory leak in receive path
When 'midev->allow_rx' is false, the newly allocated skb isn't consumed
by netif_rx(), it needs to free the skb directly.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
serial: caif: hold tty->link reference in ldisc_open and ser_release
A reproducer triggers a KASAN slab-use-after-free in pty_write_room()
when caif_serial's TX path calls tty_write_room(). The faulting access
is on tty->link->port.
Hold an extra kref on tty->link for the lifetime of the caif_serial line
discipline: get it in ldisc_open() and drop it in ser_release(), and
also drop it on the ldisc_open() error path.
With this change applied, the reproducer no longer triggers the UAF in
my testing.
CVSS Score
7.8
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
ASoC: soc-core: flush delayed work before removing DAIs and widgets
When a sound card is unbound while a PCM stream is open, a
use-after-free can occur in snd_soc_dapm_stream_event(), called from
the close_delayed_work workqueue handler.
During unbind, snd_soc_unbind_card() flushes delayed work and then
calls soc_cleanup_card_resources(). Inside cleanup,
snd_card_disconnect_sync() releases all PCM file descriptors, and
the resulting PCM close path can call snd_soc_dapm_stream_stop()
which schedules new delayed work with a pmdown_time timer delay.
Since this happens after the flush in snd_soc_unbind_card(), the
new work is not caught. soc_remove_link_components() then frees
DAPM widgets before this work fires, leading to the use-after-free.
The existing flush in soc_free_pcm_runtime() also cannot help as it
runs after soc_remove_link_components() has already freed the widgets.
Add a flush in soc_cleanup_card_resources() after
snd_card_disconnect_sync() (after which no new PCM closes can
schedule further delayed work) and before soc_remove_link_dais()
and soc_remove_link_components() (which tear down the structures the
delayed work accesses).
CVSS Score
7.3
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
nvme-pci: Fix race bug in nvme_poll_irqdisable()
In the following scenario, pdev can be disabled between (1) and (3) by
(2). This sets pdev->msix_enabled = 0. Then, pci_irq_vector() will
return MSI-X IRQ(>15) for (1) whereas return INTx IRQ(<=15) for (2).
This causes IRQ warning because it tries to enable INTx IRQ that has
never been disabled before.
To fix this, save IRQ number into a local variable and ensure
disable_irq() and enable_irq() operate on the same IRQ number. Even if
pci_free_irq_vectors() frees the IRQ concurrently, disable_irq() and
enable_irq() on a stale IRQ number is still valid and safe, and the
depth accounting reamins balanced.
task 1:
nvme_poll_irqdisable()
disable_irq(pci_irq_vector(pdev, nvmeq->cq_vector)) ...(1)
enable_irq(pci_irq_vector(pdev, nvmeq->cq_vector)) ...(3)
task 2:
nvme_reset_work()
nvme_dev_disable()
pdev->msix_enable = 0; ...(2)
crash log:
------------[ cut here ]------------
Unbalanced enable for IRQ 10
WARNING: kernel/irq/manage.c:753 at __enable_irq+0x102/0x190 kernel/irq/manage.c:753, CPU#1: kworker/1:0H/26
Modules linked in:
CPU: 1 UID: 0 PID: 26 Comm: kworker/1:0H Not tainted 6.19.0-dirty #9 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
Workqueue: kblockd blk_mq_timeout_work
RIP: 0010:__enable_irq+0x107/0x190 kernel/irq/manage.c:753
Code: ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 79 48 8d 3d 2e 7a 3f 05 41 8b 74 24 2c <67> 48 0f b9 3a e8 ef b9 21 00 5b 41 5c 5d e9 46 54 66 03 e8 e1 b9
RSP: 0018:ffffc900001bf550 EFLAGS: 00010046
RAX: 0000000000000007 RBX: 0000000000000000 RCX: ffffffffb20c0e90
RDX: 0000000000000000 RSI: 000000000000000a RDI: ffffffffb74b88f0
RBP: ffffc900001bf560 R08: ffff88800197cf00 R09: 0000000000000001
R10: 0000000000000003 R11: 0000000000000003 R12: ffff8880012a6000
R13: 1ffff92000037eae R14: 000000000000000a R15: 0000000000000293
FS: 0000000000000000(0000) GS:ffff8880b49f7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555da4a25fa8 CR3: 00000000208e8000 CR4: 00000000000006f0
Call Trace:
<TASK>
enable_irq+0x121/0x1e0 kernel/irq/manage.c:797
nvme_poll_irqdisable+0x162/0x1c0 drivers/nvme/host/pci.c:1494
nvme_timeout+0x965/0x14b0 drivers/nvme/host/pci.c:1744
blk_mq_rq_timed_out block/blk-mq.c:1653 [inline]
blk_mq_handle_expired+0x227/0x2d0 block/blk-mq.c:1721
bt_iter+0x2fc/0x3a0 block/blk-mq-tag.c:292
__sbitmap_for_each_set include/linux/sbitmap.h:269 [inline]
sbitmap_for_each_set include/linux/sbitmap.h:290 [inline]
bt_for_each block/blk-mq-tag.c:324 [inline]
blk_mq_queue_tag_busy_iter+0x969/0x1e80 block/blk-mq-tag.c:536
blk_mq_timeout_work+0x627/0x870 block/blk-mq.c:1763
process_one_work+0x956/0x1aa0 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x65c/0xe60 kernel/workqueue.c:3421
kthread+0x41a/0x930 kernel/kthread.c:463
ret_from_fork+0x6f8/0x8c0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
</TASK>
irq event stamp: 74478
hardirqs last enabled at (74477): [<ffffffffb5720a9c>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline]
hardirqs last enabled at (74477): [<ffffffffb5720a9c>] _raw_spin_unlock_irq+0x2c/0x60 kernel/locking/spinlock.c:202
hardirqs last disabled at (74478): [<ffffffffb57207b5>] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline]
hardirqs last disabled at (74478): [<ffffffffb57207b5>] _raw_spin_lock_irqsave+0x85/0xa0 kernel/locking/spinlock.c:162
softirqs last enabled at (74304): [<ffffffffb1e9466c>] __do_softirq kernel/softirq.c:656 [inline]
softirqs last enabled at (74304): [<ffffffffb1e9466c>] invoke_softirq kernel/softirq.c:496 [inline]
softirqs last enabled at (74304): [<ffffffffb1e9466c>] __irq_exit_rcu+0xdc/0x120
---truncated---
CVSS Score
4.7
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
nvme-pci: Fix slab-out-of-bounds in nvme_dbbuf_set
dev->online_queues is a count incremented in nvme_init_queue. Thus,
valid indices are 0 through dev->online_queues − 1.
This patch fixes the loop condition to ensure the index stays within the
valid range. Index 0 is excluded because it is the admin queue.
KASAN splat:
==================================================================
BUG: KASAN: slab-out-of-bounds in nvme_dbbuf_free drivers/nvme/host/pci.c:377 [inline]
BUG: KASAN: slab-out-of-bounds in nvme_dbbuf_set+0x39c/0x400 drivers/nvme/host/pci.c:404
Read of size 2 at addr ffff88800592a574 by task kworker/u8:5/74
CPU: 0 UID: 0 PID: 74 Comm: kworker/u8:5 Not tainted 6.19.0-dirty #10 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
Workqueue: nvme-reset-wq nvme_reset_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0xea/0x150 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xce/0x5d0 mm/kasan/report.c:482
kasan_report+0xdc/0x110 mm/kasan/report.c:595
__asan_report_load2_noabort+0x18/0x20 mm/kasan/report_generic.c:379
nvme_dbbuf_free drivers/nvme/host/pci.c:377 [inline]
nvme_dbbuf_set+0x39c/0x400 drivers/nvme/host/pci.c:404
nvme_reset_work+0x36b/0x8c0 drivers/nvme/host/pci.c:3252
process_one_work+0x956/0x1aa0 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x65c/0xe60 kernel/workqueue.c:3421
kthread+0x41a/0x930 kernel/kthread.c:463
ret_from_fork+0x6f8/0x8c0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
</TASK>
Allocated by task 34 on cpu 1 at 4.241550s:
kasan_save_stack+0x2c/0x60 mm/kasan/common.c:57
kasan_save_track+0x1c/0x70 mm/kasan/common.c:78
kasan_save_alloc_info+0x3c/0x50 mm/kasan/generic.c:570
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xb5/0xc0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5657 [inline]
__kmalloc_node_noprof+0x2bf/0x8d0 mm/slub.c:5663
kmalloc_array_node_noprof include/linux/slab.h:1075 [inline]
nvme_pci_alloc_dev drivers/nvme/host/pci.c:3479 [inline]
nvme_probe+0x2f1/0x1820 drivers/nvme/host/pci.c:3534
local_pci_probe+0xef/0x1c0 drivers/pci/pci-driver.c:324
pci_call_probe drivers/pci/pci-driver.c:392 [inline]
__pci_device_probe drivers/pci/pci-driver.c:417 [inline]
pci_device_probe+0x743/0x920 drivers/pci/pci-driver.c:451
call_driver_probe drivers/base/dd.c:583 [inline]
really_probe+0x29b/0xb70 drivers/base/dd.c:661
__driver_probe_device+0x3b0/0x4a0 drivers/base/dd.c:803
driver_probe_device+0x56/0x1f0 drivers/base/dd.c:833
__driver_attach_async_helper+0x155/0x340 drivers/base/dd.c:1159
async_run_entry_fn+0xa6/0x4b0 kernel/async.c:129
process_one_work+0x956/0x1aa0 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x65c/0xe60 kernel/workqueue.c:3421
kthread+0x41a/0x930 kernel/kthread.c:463
ret_from_fork+0x6f8/0x8c0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
The buggy address belongs to the object at ffff88800592a000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 244 bytes to the right of
allocated 1152-byte region [ffff88800592a000, ffff88800592a480)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5928
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfffffc0000040(head|node=0|zone=1|lastcpupid=0x1fffff)
page_type: f5(slab)
raw: 000fffffc0000040 ffff888001042000 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000080008 00000000f5000000 0000000000000000
head: 000fffffc0000040 ffff888001042000 00000
---truncated---
CVSS Score
7.1
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nfnetlink_cthelper: fix OOB read in nfnl_cthelper_dump_table()
nfnl_cthelper_dump_table() has a 'goto restart' that jumps to a label
inside the for loop body. When the "last" helper saved in cb->args[1]
is deleted between dump rounds, every entry fails the (cur != last)
check, so cb->args[1] is never cleared. The for loop finishes with
cb->args[0] == nf_ct_helper_hsize, and the 'goto restart' jumps back
into the loop body bypassing the bounds check, causing an 8-byte
out-of-bounds read on nf_ct_helper_hash[nf_ct_helper_hsize].
The 'goto restart' block was meant to re-traverse the current bucket
when "last" is no longer found, but it was placed after the for loop
instead of inside it. Move the block into the for loop body so that
the restart only occurs while cb->args[0] is still within bounds.
BUG: KASAN: slab-out-of-bounds in nfnl_cthelper_dump_table+0x9f/0x1b0
Read of size 8 at addr ffff888104ca3000 by task poc_cthelper/131
Call Trace:
nfnl_cthelper_dump_table+0x9f/0x1b0
netlink_dump+0x333/0x880
netlink_recvmsg+0x3e2/0x4b0
sock_recvmsg+0xde/0xf0
__sys_recvfrom+0x150/0x200
__x64_sys_recvfrom+0x76/0x90
do_syscall_64+0xc3/0x6e0
Allocated by task 1:
__kvmalloc_node_noprof+0x21b/0x700
nf_ct_alloc_hashtable+0x65/0xd0
nf_conntrack_helper_init+0x21/0x60
nf_conntrack_init_start+0x18d/0x300
nf_conntrack_standalone_init+0x12/0xc0
CVSS Score
7.1
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nfnetlink_queue: fix entry leak in bridge verdict error path
nfqnl_recv_verdict() calls find_dequeue_entry() to remove the queue
entry from the queue data structures, taking ownership of the entry.
For PF_BRIDGE packets, it then calls nfqa_parse_bridge() to parse VLAN
attributes. If nfqa_parse_bridge() returns an error (e.g. NFQA_VLAN
present but NFQA_VLAN_TCI missing), the function returns immediately
without freeing the dequeued entry or its sk_buff.
This leaks the nf_queue_entry, its associated sk_buff, and all held
references (net_device refcounts, struct net refcount). Repeated
triggering exhausts kernel memory.
Fix this by dropping the entry via nfqnl_reinject() with NF_DROP verdict
on the error path, consistent with other error handling in this file.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
netfilter: x_tables: guard option walkers against 1-byte tail reads
When the last byte of options is a non-single-byte option kind, walkers
that advance with i += op[i + 1] ? : 1 can read op[i + 1] past the end
of the option area.
Add an explicit i == optlen - 1 check before dereferencing op[i + 1]
in xt_tcpudp and xt_dccp option walkers.
CVSS Score
8.2
EPSS Score
0.001
Published
2026-05-08