Linux: >> Linux Kernel >> 6.1.25 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
skbuff: skb_segment, Call zero copy functions before using skbuff frags
Commit bf5c25d60861 ("skbuff: in skb_segment, call zerocopy functions
once per nskb") added the call to zero copy functions in skb_segment().
The change introduced a bug in skb_segment() because skb_orphan_frags()
may possibly change the number of fragments or allocate new fragments
altogether leaving nrfrags and frag to point to the old values. This can
cause a panic with stacktrace like the one below.
[ 193.894380] BUG: kernel NULL pointer dereference, address: 00000000000000bc
[ 193.895273] CPU: 13 PID: 18164 Comm: vh-net-17428 Kdump: loaded Tainted: G O 5.15.123+ #26
[ 193.903919] RIP: 0010:skb_segment+0xb0e/0x12f0
[ 194.021892] Call Trace:
[ 194.027422] <TASK>
[ 194.072861] tcp_gso_segment+0x107/0x540
[ 194.082031] inet_gso_segment+0x15c/0x3d0
[ 194.090783] skb_mac_gso_segment+0x9f/0x110
[ 194.095016] __skb_gso_segment+0xc1/0x190
[ 194.103131] netem_enqueue+0x290/0xb10 [sch_netem]
[ 194.107071] dev_qdisc_enqueue+0x16/0x70
[ 194.110884] __dev_queue_xmit+0x63b/0xb30
[ 194.121670] bond_start_xmit+0x159/0x380 [bonding]
[ 194.128506] dev_hard_start_xmit+0xc3/0x1e0
[ 194.131787] __dev_queue_xmit+0x8a0/0xb30
[ 194.138225] macvlan_start_xmit+0x4f/0x100 [macvlan]
[ 194.141477] dev_hard_start_xmit+0xc3/0x1e0
[ 194.144622] sch_direct_xmit+0xe3/0x280
[ 194.147748] __dev_queue_xmit+0x54a/0xb30
[ 194.154131] tap_get_user+0x2a8/0x9c0 [tap]
[ 194.157358] tap_sendmsg+0x52/0x8e0 [tap]
[ 194.167049] handle_tx_zerocopy+0x14e/0x4c0 [vhost_net]
[ 194.173631] handle_tx+0xcd/0xe0 [vhost_net]
[ 194.176959] vhost_worker+0x76/0xb0 [vhost]
[ 194.183667] kthread+0x118/0x140
[ 194.190358] ret_from_fork+0x1f/0x30
[ 194.193670] </TASK>
In this case calling skb_orphan_frags() updated nr_frags leaving nrfrags
local variable in skb_segment() stale. This resulted in the code hitting
i >= nrfrags prematurely and trying to move to next frag_skb using
list_skb pointer, which was NULL, and caused kernel panic. Move the call
to zero copy functions before using frags and nr_frags.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: u_serial: Add null pointer check in gserial_suspend
Consider a case where gserial_disconnect has already cleared
gser->ioport. And if gserial_suspend gets called afterwards,
it will lead to accessing of gser->ioport and thus causing
null pointer dereference.
Avoid this by adding a null pointer check. Added a static
spinlock to prevent gser->ioport from becoming null after
the newly added null pointer check.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
md/raid10: check slab-out-of-bounds in md_bitmap_get_counter
If we write a large number to md/bitmap_set_bits, md_bitmap_checkpage()
will return -EINVAL because 'page >= bitmap->pages', but the return value
was not checked immediately in md_bitmap_get_counter() in order to set
*blocks value and slab-out-of-bounds occurs.
Move check of 'page >= bitmap->pages' to md_bitmap_get_counter() and
return directly if true.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix racy issue under cocurrent smb2 tree disconnect
There is UAF issue under cocurrent smb2 tree disconnect.
This patch introduce TREE_CONN_EXPIRE flags for tcon to avoid cocurrent
access.
CVSS Score
7.0
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
icmp6: Fix null-ptr-deref of ip6_null_entry->rt6i_idev in icmp6_dev().
With some IPv6 Ext Hdr (RPL, SRv6, etc.), we can send a packet that
has the link-local address as src and dst IP and will be forwarded to
an external IP in the IPv6 Ext Hdr.
For example, the script below generates a packet whose src IP is the
link-local address and dst is updated to 11::.
# for f in $(find /proc/sys/net/ -name *seg6_enabled*); do echo 1 > $f; done
# python3
>>> from socket import *
>>> from scapy.all import *
>>>
>>> SRC_ADDR = DST_ADDR = "fe80::5054:ff:fe12:3456"
>>>
>>> pkt = IPv6(src=SRC_ADDR, dst=DST_ADDR)
>>> pkt /= IPv6ExtHdrSegmentRouting(type=4, addresses=["11::", "22::"], segleft=1)
>>>
>>> sk = socket(AF_INET6, SOCK_RAW, IPPROTO_RAW)
>>> sk.sendto(bytes(pkt), (DST_ADDR, 0))
For such a packet, we call ip6_route_input() to look up a route for the
next destination in these three functions depending on the header type.
* ipv6_rthdr_rcv()
* ipv6_rpl_srh_rcv()
* ipv6_srh_rcv()
If no route is found, ip6_null_entry is set to skb, and the following
dst_input(skb) calls ip6_pkt_drop().
Finally, in icmp6_dev(), we dereference skb_rt6_info(skb)->rt6i_idev->dev
as the input device is the loopback interface. Then, we have to check if
skb_rt6_info(skb)->rt6i_idev is NULL or not to avoid NULL pointer deref
for ip6_null_entry.
BUG: kernel NULL pointer dereference, address: 0000000000000000
PF: supervisor read access in kernel mode
PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 0 PID: 157 Comm: python3 Not tainted 6.4.0-11996-gb121d614371c #35
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:icmp6_send (net/ipv6/icmp.c:436 net/ipv6/icmp.c:503)
Code: fe ff ff 48 c7 40 30 c0 86 5d 83 e8 c6 44 1c 00 e9 c8 fc ff ff 49 8b 46 58 48 83 e0 fe 0f 84 4a fb ff ff 48 8b 80 d0 00 00 00 <48> 8b 00 44 8b 88 e0 00 00 00 e9 34 fb ff ff 4d 85 ed 0f 85 69 01
RSP: 0018:ffffc90000003c70 EFLAGS: 00000286
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 00000000000000e0
RDX: 0000000000000021 RSI: 0000000000000000 RDI: ffff888006d72a18
RBP: ffffc90000003d80 R08: 0000000000000000 R09: 0000000000000001
R10: ffffc90000003d98 R11: 0000000000000040 R12: ffff888006d72a10
R13: 0000000000000000 R14: ffff8880057fb800 R15: ffffffff835d86c0
FS: 00007f9dc72ee740(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000057b2000 CR4: 00000000007506f0
PKRU: 55555554
Call Trace:
<IRQ>
ip6_pkt_drop (net/ipv6/route.c:4513)
ipv6_rthdr_rcv (net/ipv6/exthdrs.c:640 net/ipv6/exthdrs.c:686)
ip6_protocol_deliver_rcu (net/ipv6/ip6_input.c:437 (discriminator 5))
ip6_input_finish (./include/linux/rcupdate.h:781 net/ipv6/ip6_input.c:483)
__netif_receive_skb_one_core (net/core/dev.c:5455)
process_backlog (./include/linux/rcupdate.h:781 net/core/dev.c:5895)
__napi_poll (net/core/dev.c:6460)
net_rx_action (net/core/dev.c:6529 net/core/dev.c:6660)
__do_softirq (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:207 ./include/trace/events/irq.h:142 kernel/softirq.c:554)
do_softirq (kernel/softirq.c:454 kernel/softirq.c:441)
</IRQ>
<TASK>
__local_bh_enable_ip (kernel/softirq.c:381)
__dev_queue_xmit (net/core/dev.c:4231)
ip6_finish_output2 (./include/net/neighbour.h:544 net/ipv6/ip6_output.c:135)
rawv6_sendmsg (./include/net/dst.h:458 ./include/linux/netfilter.h:303 net/ipv6/raw.c:656 net/ipv6/raw.c:914)
sock_sendmsg (net/socket.c:725 net/socket.c:748)
__sys_sendto (net/socket.c:2134)
__x64_sys_sendto (net/socket.c:2146 net/socket.c:2142 net/socket.c:2142)
do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)
RIP: 0033:0x7f9dc751baea
Code: d8 64 89 02 48 c7 c0 ff f
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: Handle pairing of E-switch via uplink un/load APIs
In case user switch a device from switchdev mode to legacy mode, mlx5
first unpair the E-switch and afterwards unload the uplink vport.
From the other hand, in case user remove or reload a device, mlx5
first unload the uplink vport and afterwards unpair the E-switch.
The latter is causing a bug[1], hence, handle pairing of E-switch as
part of uplink un/load APIs.
[1]
In case VF_LAG is used, every tc fdb flow is duplicated to the peer
esw. However, the original esw keeps a pointer to this duplicated
flow, not the peer esw.
e.g.: if user create tc fdb flow over esw0, the flow is duplicated
over esw1, in FW/HW, but in SW, esw0 keeps a pointer to the duplicated
flow.
During module unload while a peer tc fdb flow is still offloaded, in
case the first device to be removed is the peer device (esw1 in the
example above), the peer net-dev is destroyed, and so the mlx5e_priv
is memset to 0.
Afterwards, the peer device is trying to unpair himself from the
original device (esw0 in the example above). Unpair API invoke the
original device to clear peer flow from its eswitch (esw0), but the
peer flow, which is stored over the original eswitch (esw0), is
trying to use the peer mlx5e_priv, which is memset to 0 and result in
bellow kernel-oops.
[ 157.964081 ] BUG: unable to handle page fault for address: 000000000002ce60
[ 157.964662 ] #PF: supervisor read access in kernel mode
[ 157.965123 ] #PF: error_code(0x0000) - not-present page
[ 157.965582 ] PGD 0 P4D 0
[ 157.965866 ] Oops: 0000 [#1] SMP
[ 157.967670 ] RIP: 0010:mlx5e_tc_del_fdb_flow+0x48/0x460 [mlx5_core]
[ 157.976164 ] Call Trace:
[ 157.976437 ] <TASK>
[ 157.976690 ] __mlx5e_tc_del_fdb_peer_flow+0xe6/0x100 [mlx5_core]
[ 157.977230 ] mlx5e_tc_clean_fdb_peer_flows+0x67/0x90 [mlx5_core]
[ 157.977767 ] mlx5_esw_offloads_unpair+0x2d/0x1e0 [mlx5_core]
[ 157.984653 ] mlx5_esw_offloads_devcom_event+0xbf/0x130 [mlx5_core]
[ 157.985212 ] mlx5_devcom_send_event+0xa3/0xb0 [mlx5_core]
[ 157.985714 ] esw_offloads_disable+0x5a/0x110 [mlx5_core]
[ 157.986209 ] mlx5_eswitch_disable_locked+0x152/0x170 [mlx5_core]
[ 157.986757 ] mlx5_eswitch_disable+0x51/0x80 [mlx5_core]
[ 157.987248 ] mlx5_unload+0x2a/0xb0 [mlx5_core]
[ 157.987678 ] mlx5_uninit_one+0x5f/0xd0 [mlx5_core]
[ 157.988127 ] remove_one+0x64/0xe0 [mlx5_core]
[ 157.988549 ] pci_device_remove+0x31/0xa0
[ 157.988933 ] device_release_driver_internal+0x18f/0x1f0
[ 157.989402 ] driver_detach+0x3f/0x80
[ 157.989754 ] bus_remove_driver+0x70/0xf0
[ 157.990129 ] pci_unregister_driver+0x34/0x90
[ 157.990537 ] mlx5_cleanup+0xc/0x1c [mlx5_core]
[ 157.990972 ] __x64_sys_delete_module+0x15a/0x250
[ 157.991398 ] ? exit_to_user_mode_prepare+0xea/0x110
[ 157.991840 ] do_syscall_64+0x3d/0x90
[ 157.992198 ] entry_SYSCALL_64_after_hwframe+0x46/0xb0
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix BUG_ON condition in btrfs_cancel_balance
Pausing and canceling balance can race to interrupt balance lead to BUG_ON
panic in btrfs_cancel_balance. The BUG_ON condition in btrfs_cancel_balance
does not take this race scenario into account.
However, the race condition has no other side effects. We can fix that.
Reproducing it with panic trace like this:
kernel BUG at fs/btrfs/volumes.c:4618!
RIP: 0010:btrfs_cancel_balance+0x5cf/0x6a0
Call Trace:
<TASK>
? do_nanosleep+0x60/0x120
? hrtimer_nanosleep+0xb7/0x1a0
? sched_core_clone_cookie+0x70/0x70
btrfs_ioctl_balance_ctl+0x55/0x70
btrfs_ioctl+0xa46/0xd20
__x64_sys_ioctl+0x7d/0xa0
do_syscall_64+0x38/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
Race scenario as follows:
> mutex_unlock(&fs_info->balance_mutex);
> --------------------
> .......issue pause and cancel req in another thread
> --------------------
> ret = __btrfs_balance(fs_info);
>
> mutex_lock(&fs_info->balance_mutex);
> if (ret == -ECANCELED && atomic_read(&fs_info->balance_pause_req)) {
> btrfs_info(fs_info, "balance: paused");
> btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
> }
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: Collect command failures data only for known commands
DEVX can issue a general command, which is not used by mlx5 driver.
In case such command is failed, mlx5 is trying to collect the failure
data, However, mlx5 doesn't create a storage for this command, since
mlx5 doesn't use it. This lead to array-index-out-of-bounds error.
Fix it by checking whether the command is known before collecting the
failure data.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
net: marvell: prestera: fix handling IPv4 routes with nhid
Fix handling IPv4 routes referencing a nexthop via its id by replacing
calls to fib_info_nh() with fib_info_nhc().
Trying to add an IPv4 route referencing a nextop via nhid:
$ ip link set up swp5
$ ip a a 10.0.0.1/24 dev swp5
$ ip nexthop add dev swp5 id 20 via 10.0.0.2
$ ip route add 10.0.1.0/24 nhid 20
triggers warnings when trying to handle the route:
[ 528.805763] ------------[ cut here ]------------
[ 528.810437] WARNING: CPU: 3 PID: 53 at include/net/nexthop.h:468 __prestera_fi_is_direct+0x2c/0x68 [prestera]
[ 528.820434] Modules linked in: prestera_pci act_gact act_police sch_ingress cls_u32 cls_flower prestera arm64_delta_tn48m_dn_led(O) arm64_delta_tn48m_dn_cpld(O) [last unloaded: prestera_pci]
[ 528.837485] CPU: 3 PID: 53 Comm: kworker/u8:3 Tainted: G O 6.4.5 #1
[ 528.845178] Hardware name: delta,tn48m-dn (DT)
[ 528.849641] Workqueue: prestera_ordered __prestera_router_fib_event_work [prestera]
[ 528.857352] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 528.864347] pc : __prestera_fi_is_direct+0x2c/0x68 [prestera]
[ 528.870135] lr : prestera_k_arb_fib_evt+0xb20/0xd50 [prestera]
[ 528.876007] sp : ffff80000b20bc90
[ 528.879336] x29: ffff80000b20bc90 x28: 0000000000000000 x27: ffff0001374d3a48
[ 528.886510] x26: ffff000105604000 x25: ffff000134af8a28 x24: ffff0001374d3800
[ 528.893683] x23: ffff000101c89148 x22: ffff000101c89000 x21: ffff000101c89200
[ 528.900855] x20: ffff00013641fda0 x19: ffff800009d01088 x18: 0000000000000059
[ 528.908027] x17: 0000000000000277 x16: 0000000000000000 x15: 0000000000000000
[ 528.915198] x14: 0000000000000003 x13: 00000000000fe400 x12: 0000000000000000
[ 528.922371] x11: 0000000000000002 x10: 0000000000000aa0 x9 : ffff8000013d2020
[ 528.929543] x8 : 0000000000000018 x7 : 000000007b1703f8 x6 : 000000001ca72f86
[ 528.936715] x5 : 0000000033399ea7 x4 : 0000000000000000 x3 : ffff0001374d3acc
[ 528.943886] x2 : 0000000000000000 x1 : ffff00010200de00 x0 : ffff000134ae3f80
[ 528.951058] Call trace:
[ 528.953516] __prestera_fi_is_direct+0x2c/0x68 [prestera]
[ 528.958952] __prestera_router_fib_event_work+0x100/0x158 [prestera]
[ 528.965348] process_one_work+0x208/0x488
[ 528.969387] worker_thread+0x4c/0x430
[ 528.973068] kthread+0x120/0x138
[ 528.976313] ret_from_fork+0x10/0x20
[ 528.979909] ---[ end trace 0000000000000000 ]---
[ 528.984998] ------------[ cut here ]------------
[ 528.989645] WARNING: CPU: 3 PID: 53 at include/net/nexthop.h:468 __prestera_fi_is_direct+0x2c/0x68 [prestera]
[ 528.999628] Modules linked in: prestera_pci act_gact act_police sch_ingress cls_u32 cls_flower prestera arm64_delta_tn48m_dn_led(O) arm64_delta_tn48m_dn_cpld(O) [last unloaded: prestera_pci]
[ 529.016676] CPU: 3 PID: 53 Comm: kworker/u8:3 Tainted: G W O 6.4.5 #1
[ 529.024368] Hardware name: delta,tn48m-dn (DT)
[ 529.028830] Workqueue: prestera_ordered __prestera_router_fib_event_work [prestera]
[ 529.036539] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 529.043533] pc : __prestera_fi_is_direct+0x2c/0x68 [prestera]
[ 529.049318] lr : __prestera_k_arb_fc_apply+0x280/0x2f8 [prestera]
[ 529.055452] sp : ffff80000b20bc60
[ 529.058781] x29: ffff80000b20bc60 x28: 0000000000000000 x27: ffff0001374d3a48
[ 529.065953] x26: ffff000105604000 x25: ffff000134af8a28 x24: ffff0001374d3800
[ 529.073126] x23: ffff000101c89148 x22: ffff000101c89148 x21: ffff00013641fda0
[ 529.080299] x20: ffff000101c89000 x19: ffff000101c89020 x18: 0000000000000059
[ 529.087471] x17: 0000000000000277 x16: 0000000000000000 x15: 0000000000000000
[ 529.094642] x14: 0000000000000003 x13: 00000000000fe400 x12: 0000000000000000
[ 529.101814] x11: 0000000000000002 x10: 0000000000000aa0 x9 : ffff8000013cee80
[ 529.108985] x8 : 0000000000000018 x7 : 000000007b1703f8 x6
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
media: ipu-bridge: Fix null pointer deref on SSDB/PLD parsing warnings
When ipu_bridge_parse_rotation() and ipu_bridge_parse_orientation() run
sensor->adev is not set yet.
So if either of the dev_warn() calls about unknown values are hit this
will lead to a NULL pointer deref.
Set sensor->adev earlier, with a borrowed ref to avoid making unrolling
on errors harder, to fix this.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17