Linux: >> Linux Kernel >> 4.17.18 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
crypto: af_alg - Set merge to zero early in af_alg_sendmsg
If an error causes af_alg_sendmsg to abort, ctx->merge may contain
a garbage value from the previous loop. This may then trigger a
crash on the next entry into af_alg_sendmsg when it attempts to do
a merge that can't be done.
Fix this by setting ctx->merge to zero near the start of the loop.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
smb: client: let smbd_destroy() call disable_work_sync(&info->post_send_credits_work)
In smbd_destroy() we may destroy the memory so we better
wait until post_send_credits_work is no longer pending
and will never be started again.
I actually just hit the case using rxe:
WARNING: CPU: 0 PID: 138 at drivers/infiniband/sw/rxe/rxe_verbs.c:1032 rxe_post_recv+0x1ee/0x480 [rdma_rxe]
...
[ 5305.686979] [ T138] smbd_post_recv+0x445/0xc10 [cifs]
[ 5305.687135] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5
[ 5305.687149] [ T138] ? __kasan_check_write+0x14/0x30
[ 5305.687185] [ T138] ? __pfx_smbd_post_recv+0x10/0x10 [cifs]
[ 5305.687329] [ T138] ? __pfx__raw_spin_lock_irqsave+0x10/0x10
[ 5305.687356] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5
[ 5305.687368] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5
[ 5305.687378] [ T138] ? _raw_spin_unlock_irqrestore+0x11/0x60
[ 5305.687389] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5
[ 5305.687399] [ T138] ? get_receive_buffer+0x168/0x210 [cifs]
[ 5305.687555] [ T138] smbd_post_send_credits+0x382/0x4b0 [cifs]
[ 5305.687701] [ T138] ? __pfx_smbd_post_send_credits+0x10/0x10 [cifs]
[ 5305.687855] [ T138] ? __pfx___schedule+0x10/0x10
[ 5305.687865] [ T138] ? __pfx__raw_spin_lock_irq+0x10/0x10
[ 5305.687875] [ T138] ? queue_delayed_work_on+0x8e/0xa0
[ 5305.687889] [ T138] process_one_work+0x629/0xf80
[ 5305.687908] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5
[ 5305.687917] [ T138] ? __kasan_check_write+0x14/0x30
[ 5305.687933] [ T138] worker_thread+0x87f/0x1570
...
It means rxe_post_recv was called after rdma_destroy_qp().
This happened because put_receive_buffer() was triggered
by ib_drain_qp() and called:
queue_work(info->workqueue, &info->post_send_credits_work);
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix smbdirect_recv_io leak in smbd_negotiate() error path
During tests of another unrelated patch I was able to trigger this
error: Objects remaining on __kmem_cache_shutdown()
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
PM / devfreq: Fix leak in devfreq_dev_release()
srcu_init_notifier_head() allocates resources that need to be released
with a srcu_cleanup_notifier_head() call.
Reported by kmemleak.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
media: v4l2-mem2mem: add lock to protect parameter num_rdy
Getting below error when using KCSAN to check the driver. Adding lock to
protect parameter num_rdy when getting the value with function:
v4l2_m2m_num_src_bufs_ready/v4l2_m2m_num_dst_bufs_ready.
kworker/u16:3: [name:report&]BUG: KCSAN: data-race in v4l2_m2m_buf_queue
kworker/u16:3: [name:report&]
kworker/u16:3: [name:report&]read-write to 0xffffff8105f35b94 of 1 bytes by task 20865 on cpu 7:
kworker/u16:3: v4l2_m2m_buf_queue+0xd8/0x10c
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
scsi: ses: Fix slab-out-of-bounds in ses_intf_remove()
A fix for:
BUG: KASAN: slab-out-of-bounds in ses_intf_remove+0x23f/0x270 [ses]
Read of size 8 at addr ffff88a10d32e5d8 by task rmmod/12013
When edev->components is zero, accessing edev->component[0] members is
wrong.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
scsi: mpt3sas: Fix a memory leak
Add a forgotten kfree().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
nbd: fix incomplete validation of ioctl arg
We tested and found an alarm caused by nbd_ioctl arg without verification.
The UBSAN warning calltrace like below:
UBSAN: Undefined behaviour in fs/buffer.c:1709:35
signed integer overflow:
-9223372036854775808 - 1 cannot be represented in type 'long long int'
CPU: 3 PID: 2523 Comm: syz-executor.0 Not tainted 4.19.90 #1
Hardware name: linux,dummy-virt (DT)
Call trace:
dump_backtrace+0x0/0x3f0 arch/arm64/kernel/time.c:78
show_stack+0x28/0x38 arch/arm64/kernel/traps.c:158
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x170/0x1dc lib/dump_stack.c:118
ubsan_epilogue+0x18/0xb4 lib/ubsan.c:161
handle_overflow+0x188/0x1dc lib/ubsan.c:192
__ubsan_handle_sub_overflow+0x34/0x44 lib/ubsan.c:206
__block_write_full_page+0x94c/0xa20 fs/buffer.c:1709
block_write_full_page+0x1f0/0x280 fs/buffer.c:2934
blkdev_writepage+0x34/0x40 fs/block_dev.c:607
__writepage+0x68/0xe8 mm/page-writeback.c:2305
write_cache_pages+0x44c/0xc70 mm/page-writeback.c:2240
generic_writepages+0xdc/0x148 mm/page-writeback.c:2329
blkdev_writepages+0x2c/0x38 fs/block_dev.c:2114
do_writepages+0xd4/0x250 mm/page-writeback.c:2344
The reason for triggering this warning is __block_write_full_page()
-> i_size_read(inode) - 1 overflow.
inode->i_size is assigned in __nbd_ioctl() -> nbd_set_size() -> bytesize.
We think it is necessary to limit the size of arg to prevent errors.
Moreover, __nbd_ioctl() -> nbd_add_socket(), arg will be cast to int.
Assuming the value of arg is 0x80000000000000001) (on a 64-bit machine),
it will become 1 after the coercion, which will return unexpected results.
Fix it by adding checks to prevent passing in too large numbers.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
virtio-mmio: don't break lifecycle of vm_dev
vm_dev has a separate lifecycle because it has a 'struct device'
embedded. Thus, having a release callback for it is correct.
Allocating the vm_dev struct with devres totally breaks this protection,
though. Instead of waiting for the vm_dev release callback, the memory
is freed when the platform_device is removed. Resulting in a
use-after-free when finally the callback is to be called.
To easily see the problem, compile the kernel with
CONFIG_DEBUG_KOBJECT_RELEASE and unbind with sysfs.
The fix is easy, don't use devres in this case.
Found during my research about object lifetime problems.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
tipc: do not update mtu if msg_max is too small in mtu negotiation
When doing link mtu negotiation, a malicious peer may send Activate msg
with a very small mtu, e.g. 4 in Shuang's testing, without checking for
the minimum mtu, l->mtu will be set to 4 in tipc_link_proto_rcv(), then
n->links[bearer_id].mtu is set to 4294967228, which is a overflow of
'4 - INT_H_SIZE - EMSG_OVERHEAD' in tipc_link_mss().
With tipc_link.mtu = 4, tipc_link_xmit() kept printing the warning:
tipc: Too large msg, purging xmit list 1 5 0 40 4!
tipc: Too large msg, purging xmit list 1 15 0 60 4!
And with tipc_link_entry.mtu 4294967228, a huge skb was allocated in
named_distribute(), and when purging it in tipc_link_xmit(), a crash
was even caused:
general protection fault, probably for non-canonical address 0x2100001011000dd: 0000 [#1] PREEMPT SMP PTI
CPU: 0 PID: 0 Comm: swapper/0 Kdump: loaded Not tainted 6.3.0.neta #19
RIP: 0010:kfree_skb_list_reason+0x7e/0x1f0
Call Trace:
<IRQ>
skb_release_data+0xf9/0x1d0
kfree_skb_reason+0x40/0x100
tipc_link_xmit+0x57a/0x740 [tipc]
tipc_node_xmit+0x16c/0x5c0 [tipc]
tipc_named_node_up+0x27f/0x2c0 [tipc]
tipc_node_write_unlock+0x149/0x170 [tipc]
tipc_rcv+0x608/0x740 [tipc]
tipc_udp_recv+0xdc/0x1f0 [tipc]
udp_queue_rcv_one_skb+0x33e/0x620
udp_unicast_rcv_skb.isra.72+0x75/0x90
__udp4_lib_rcv+0x56d/0xc20
ip_protocol_deliver_rcu+0x100/0x2d0
This patch fixes it by checking the new mtu against tipc_bearer_min_mtu(),
and not updating mtu if it is too small.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01