Linux: >> Linux Kernel >> 5.15.204 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
tcp: fix potential race in tcp_v6_syn_recv_sock()
Code in tcp_v6_syn_recv_sock() after the call to tcp_v4_syn_recv_sock()
is done too late.
After tcp_v4_syn_recv_sock(), the child socket is already visible
from TCP ehash table and other cpus might use it.
Since newinet->pinet6 is still pointing to the listener ipv6_pinfo
bad things can happen as syzbot found.
Move the problematic code in tcp_v6_mapped_child_init()
and call this new helper from tcp_v4_syn_recv_sock() before
the ehash insertion.
This allows the removal of one tcp_sync_mss(), since
tcp_v4_syn_recv_sock() will call it with the correct
context.
CVSS Score
9.8
EPSS Score
0.004
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix signededness bug in smb_direct_prepare_negotiation()
smb_direct_prepare_negotiation() casts an unsigned __u32 value
from sp->max_recv_size and req->preferred_send_size to a signed
int before computing min_t(int, ...). A maliciously provided
preferred_send_size of 0x80000000 will return as smaller than
max_recv_size, and then be used to set the maximum allowed
alowed receive size for the next message.
By sending a second message with a large value (>1420 bytes)
the attacker can then achieve a heap buffer overflow.
This fix replaces min_t(int, ...) with min_t(u32)
CVSS Score
9.8
EPSS Score
0.005
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
usb: dwc3: gadget: Move vbus draw to workqueue context
Currently dwc3_gadget_vbus_draw() can be called from atomic
context, which in turn invokes power-supply-core APIs. And
some these PMIC APIs have operations that may sleep, leading
to kernel panic.
Fix this by moving the vbus_draw into a workqueue context.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: fix 22000 series SMEM parsing
If the firmware were to report three LMACs (which doesn't
exist in hardware) then using "fwrt->smem_cfg.lmac[2]" is
an overrun of the array. Reject such and use IWL_FW_CHECK
instead of WARN_ON in this function.
CVSS Score
8.8
EPSS Score
0.003
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Skip dev-iotlb flush for inaccessible PCIe device without scalable mode
PCIe endpoints with ATS enabled and passed through to userspace
(e.g., QEMU, DPDK) can hard-lock the host when their link drops,
either by surprise removal or by a link fault.
Commit 4fc82cd907ac ("iommu/vt-d: Don't issue ATS Invalidation
request when device is disconnected") adds pci_dev_is_disconnected()
to devtlb_invalidation_with_pasid() so ATS invalidation is skipped
only when the device is being safely removed, but it applies only
when Intel IOMMU scalable mode is enabled.
With scalable mode disabled or unsupported, a system hard-lock
occurs when a PCIe endpoint's link drops because the Intel IOMMU
waits indefinitely for an ATS invalidation that cannot complete.
Call Trace:
qi_submit_sync
qi_flush_dev_iotlb
__context_flush_dev_iotlb.part.0
domain_context_clear_one_cb
pci_for_each_dma_alias
device_block_translation
blocking_domain_attach_dev
iommu_deinit_device
__iommu_group_remove_device
iommu_release_device
iommu_bus_notifier
blocking_notifier_call_chain
bus_notify
device_del
pci_remove_bus_device
pci_stop_and_remove_bus_device
pciehp_unconfigure_device
pciehp_disable_slot
pciehp_handle_presence_or_link_change
pciehp_ist
Commit 81e921fd3216 ("iommu/vt-d: Fix NULL domain on device release")
adds intel_pasid_teardown_sm_context() to intel_iommu_release_device(),
which calls qi_flush_dev_iotlb() and can also hard-lock the system
when a PCIe endpoint's link drops.
Call Trace:
qi_submit_sync
qi_flush_dev_iotlb
__context_flush_dev_iotlb.part.0
intel_context_flush_no_pasid
device_pasid_table_teardown
pci_pasid_table_teardown
pci_for_each_dma_alias
intel_pasid_teardown_sm_context
intel_iommu_release_device
iommu_deinit_device
__iommu_group_remove_device
iommu_release_device
iommu_bus_notifier
blocking_notifier_call_chain
bus_notify
device_del
pci_remove_bus_device
pci_stop_and_remove_bus_device
pciehp_unconfigure_device
pciehp_disable_slot
pciehp_handle_presence_or_link_change
pciehp_ist
Sometimes the endpoint loses connection without a link-down event
(e.g., due to a link fault); killing the process (virsh destroy)
then hard-locks the host.
Call Trace:
qi_submit_sync
qi_flush_dev_iotlb
__context_flush_dev_iotlb.part.0
domain_context_clear_one_cb
pci_for_each_dma_alias
device_block_translation
blocking_domain_attach_dev
__iommu_attach_device
__iommu_device_set_domain
__iommu_group_set_domain_internal
iommu_detach_group
vfio_iommu_type1_detach_group
vfio_group_detach_container
vfio_group_fops_release
__fput
pci_dev_is_disconnected() only covers safe-removal paths;
pci_device_is_present() tests accessibility by reading
vendor/device IDs and internally calls pci_dev_is_disconnected().
On a ConnectX-5 (8 GT/s, x2) this costs ~70 µs.
Since __context_flush_dev_iotlb() is only called on
{attach,release}_dev paths (not hot), add pci_device_is_present()
there to skip inaccessible devices and avoid the hard-lock.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
media: tegra-video: Fix memory leak in __tegra_channel_try_format()
The state object allocated by __v4l2_subdev_state_alloc() must be freed
with __v4l2_subdev_state_free() when it is no longer needed.
In __tegra_channel_try_format(), two error paths return directly after
v4l2_subdev_call() fails, without freeing the allocated 'sd_state'
object. This violates the requirement and causes a memory leak.
Fix this by introducing a cleanup label and using goto statements in the
error paths to ensure that __v4l2_subdev_state_free() is always called
before the function returns.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
xfrm: always flush state and policy upon NETDEV_UNREGISTER event
syzbot is reporting that "struct xfrm_state" refcount is leaking.
unregister_netdevice: waiting for netdevsim0 to become free. Usage count = 2
ref_tracker: netdev@ffff888052f24618 has 1/1 users at
__netdev_tracker_alloc include/linux/netdevice.h:4400 [inline]
netdev_tracker_alloc include/linux/netdevice.h:4412 [inline]
xfrm_dev_state_add+0x3a5/0x1080 net/xfrm/xfrm_device.c:316
xfrm_state_construct net/xfrm/xfrm_user.c:986 [inline]
xfrm_add_sa+0x34ff/0x5fa0 net/xfrm/xfrm_user.c:1022
xfrm_user_rcv_msg+0x58e/0xc00 net/xfrm/xfrm_user.c:3507
netlink_rcv_skb+0x158/0x420 net/netlink/af_netlink.c:2550
xfrm_netlink_rcv+0x71/0x90 net/xfrm/xfrm_user.c:3529
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa5d/0xc30 net/socket.c:2592
___sys_sendmsg+0x134/0x1d0 net/socket.c:2646
__sys_sendmsg+0x16d/0x220 net/socket.c:2678
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
This is because commit d77e38e612a0 ("xfrm: Add an IPsec hardware
offloading API") implemented xfrm_dev_unregister() as no-op despite
xfrm_dev_state_add() from xfrm_state_construct() acquires a reference
to "struct net_device".
I guess that that commit expected that NETDEV_DOWN event is fired before
NETDEV_UNREGISTER event fires, and also assumed that xfrm_dev_state_add()
is called only if (dev->features & NETIF_F_HW_ESP) != 0.
Sabrina Dubroca identified steps to reproduce the same symptoms as below.
echo 0 > /sys/bus/netdevsim/new_device
dev=$(ls -1 /sys/bus/netdevsim/devices/netdevsim0/net/)
ip xfrm state add src 192.168.13.1 dst 192.168.13.2 proto esp \
spi 0x1000 mode tunnel aead 'rfc4106(gcm(aes))' $key 128 \
offload crypto dev $dev dir out
ethtool -K $dev esp-hw-offload off
echo 0 > /sys/bus/netdevsim/del_device
Like these steps indicate, the NETIF_F_HW_ESP bit can be cleared after
xfrm_dev_state_add() acquired a reference to "struct net_device".
Also, xfrm_dev_state_add() does not check for the NETIF_F_HW_ESP bit
when acquiring a reference to "struct net_device".
Commit 03891f820c21 ("xfrm: handle NETDEV_UNREGISTER for xfrm device")
re-introduced the NETDEV_UNREGISTER event to xfrm_dev_event(), but that
commit for unknown reason chose to share xfrm_dev_down() between the
NETDEV_DOWN event and the NETDEV_UNREGISTER event.
I guess that that commit missed the behavior in the previous paragraph.
Therefore, we need to re-introduce xfrm_dev_unregister() in order to
release the reference to "struct net_device" by unconditionally flushing
state and policy.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
xfs: remove xfs_attr_leaf_hasname
The calling convention of xfs_attr_leaf_hasname() is problematic, because
it returns a NULL buffer when xfs_attr3_leaf_read fails, a valid buffer
when xfs_attr3_leaf_lookup_int returns -ENOATTR or -EEXIST, and a
non-NULL buffer pointer for an already released buffer when
xfs_attr3_leaf_lookup_int fails with other error values.
Fix this by simply open coding xfs_attr_leaf_hasname in the callers, so
that the buffer release code is done by each caller of
xfs_attr3_leaf_read.
CVSS Score
7.8
EPSS Score
0.001
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
mfd: core: Add locking around 'mfd_of_node_list'
Manipulating a list in the kernel isn't safe without some sort of
mutual exclusion. Add a mutex any time we access / modify
'mfd_of_node_list' to prevent possible crashes.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-06
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/pm: Fix null pointer dereference issue
If SMU is disabled, during RAS initialization,
there will be null pointer dereference issue here.
CVSS Score
5.5
EPSS Score
0.001
Published
2026-05-06