Linux: >> Linux Kernel >> 6.1.40 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
ipmi_si: fix a memleak in try_smi_init()
Kmemleak reported the following leak info in try_smi_init():
unreferenced object 0xffff00018ecf9400 (size 1024):
comm "modprobe", pid 2707763, jiffies 4300851415 (age 773.308s)
backtrace:
[<000000004ca5b312>] __kmalloc+0x4b8/0x7b0
[<00000000953b1072>] try_smi_init+0x148/0x5dc [ipmi_si]
[<000000006460d325>] 0xffff800081b10148
[<0000000039206ea5>] do_one_initcall+0x64/0x2a4
[<00000000601399ce>] do_init_module+0x50/0x300
[<000000003c12ba3c>] load_module+0x7a8/0x9e0
[<00000000c246fffe>] __se_sys_init_module+0x104/0x180
[<00000000eea99093>] __arm64_sys_init_module+0x24/0x30
[<0000000021b1ef87>] el0_svc_common.constprop.0+0x94/0x250
[<0000000070f4f8b7>] do_el0_svc+0x48/0xe0
[<000000005a05337f>] el0_svc+0x24/0x3c
[<000000005eb248d6>] el0_sync_handler+0x160/0x164
[<0000000030a59039>] el0_sync+0x160/0x180
The problem was that when an error occurred before handlers registration
and after allocating `new_smi->si_sm`, the variable wouldn't be freed in
the error handling afterwards since `shutdown_smi()` hadn't been
registered yet. Fix it by adding a `kfree()` in the error handling path
in `try_smi_init()`.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
drivers: base: Free devm resources when unregistering a device
In the current code, devres_release_all() only gets called if the device
has a bus and has been probed.
This leads to issues when using bus-less or driver-less devices where
the device might never get freed if a managed resource holds a reference
to the device. This is happening in the DRM framework for example.
We should thus call devres_release_all() in the device_del() function to
make sure that the device-managed actions are properly executed when the
device is unregistered, even if it has neither a bus nor a driver.
This is effectively the same change than commit 2f8d16a996da ("devres:
release resources on device_del()") that got reverted by commit
a525a3ddeaca ("driver core: free devres in device_release") over
memory leaks concerns.
This patch effectively combines the two commits mentioned above to
release the resources both on device_del() and device_release() and get
the best of both worlds.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
cifs: fix mid leak during reconnection after timeout threshold
When the number of responses with status of STATUS_IO_TIMEOUT
exceeds a specified threshold (NUM_STATUS_IO_TIMEOUT), we reconnect
the connection. But we do not return the mid, or the credits
returned for the mid, or reduce the number of in-flight requests.
This bug could result in the server->in_flight count to go bad,
and also cause a leak in the mids.
This change moves the check to a few lines below where the
response is decrypted, even of the response is read from the
transform header. This way, the code for returning the mids
can be reused.
Also, the cifs_reconnect was reconnecting just the transport
connection before. In case of multi-channel, this may not be
what we want to do after several timeouts. Changed that to
reconnect the session and the tree too.
Also renamed NUM_STATUS_IO_TIMEOUT to a more appropriate name
MAX_STATUS_IO_TIMEOUT.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
tunnels: fix kasan splat when generating ipv4 pmtu error
If we try to emit an icmp error in response to a nonliner skb, we get
BUG: KASAN: slab-out-of-bounds in ip_compute_csum+0x134/0x220
Read of size 4 at addr ffff88811c50db00 by task iperf3/1691
CPU: 2 PID: 1691 Comm: iperf3 Not tainted 6.5.0-rc3+ #309
[..]
kasan_report+0x105/0x140
ip_compute_csum+0x134/0x220
iptunnel_pmtud_build_icmp+0x554/0x1020
skb_tunnel_check_pmtu+0x513/0xb80
vxlan_xmit_one+0x139e/0x2ef0
vxlan_xmit+0x1867/0x2760
dev_hard_start_xmit+0x1ee/0x4f0
br_dev_queue_push_xmit+0x4d1/0x660
[..]
ip_compute_csum() cannot deal with nonlinear skbs, so avoid it.
After this change, splat is gone and iperf3 is no longer stuck.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: fix memory leak in WMI firmware stats
Memory allocated for firmware pdev, vdev and beacon statistics
are not released during rmmod.
Fix it by calling ath11k_fw_stats_free() function before hardware
unregister.
While at it, avoid calling ath11k_fw_stats_free() while processing
the firmware stats received in the WMI event because the local list
is getting spliced and reinitialised and hence there are no elements
in the list after splicing.
Tested-on: QCN9074 hw1.0 PCI WLAN.HK.2.7.0.1-01744-QCAHKSWPL_SILICONZ-1
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: check for station first in client probe
When probing a client, first check if we have it, and then
check for the channel context, otherwise you can trigger
the warning there easily by probing when the AP isn't even
started yet. Since a client existing means the AP is also
operating, we can then keep the warning.
Also simplify the moved code a bit.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
cifs: Release folio lock on fscache read hit.
Under the current code, when cifs_readpage_worker is called, the call
contract is that the callee should unlock the page. This is documented
in the read_folio section of Documentation/filesystems/vfs.rst as:
> The filesystem should unlock the folio once the read has completed,
> whether it was successful or not.
Without this change, when fscache is in use and cache hit occurs during
a read, the page lock is leaked, producing the following stack on
subsequent reads (via mmap) to the page:
$ cat /proc/3890/task/12864/stack
[<0>] folio_wait_bit_common+0x124/0x350
[<0>] filemap_read_folio+0xad/0xf0
[<0>] filemap_fault+0x8b1/0xab0
[<0>] __do_fault+0x39/0x150
[<0>] do_fault+0x25c/0x3e0
[<0>] __handle_mm_fault+0x6ca/0xc70
[<0>] handle_mm_fault+0xe9/0x350
[<0>] do_user_addr_fault+0x225/0x6c0
[<0>] exc_page_fault+0x84/0x1b0
[<0>] asm_exc_page_fault+0x27/0x30
This requires a reboot to resolve; it is a deadlock.
Note however that the call to cifs_readpage_from_fscache does mark the
page clean, but does not free the folio lock. This happens in
__cifs_readpage_from_fscache on success. Releasing the lock at that
point however is not appropriate as cifs_readahead also calls
cifs_readpage_from_fscache and *does* unconditionally release the lock
after its return. This change therefore effectively makes
cifs_readpage_worker work like cifs_readahead.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
bpf: reject unhashed sockets in bpf_sk_assign
The semantics for bpf_sk_assign are as follows:
sk = some_lookup_func()
bpf_sk_assign(skb, sk)
bpf_sk_release(sk)
That is, the sk is not consumed by bpf_sk_assign. The function
therefore needs to make sure that sk lives long enough to be
consumed from __inet_lookup_skb. The path through the stack for a
TCPv4 packet is roughly:
netif_receive_skb_core: takes RCU read lock
__netif_receive_skb_core:
sch_handle_ingress:
tcf_classify:
bpf_sk_assign()
deliver_ptype_list_skb:
deliver_skb:
ip_packet_type->func == ip_rcv:
ip_rcv_core:
ip_rcv_finish_core:
dst_input:
ip_local_deliver:
ip_local_deliver_finish:
ip_protocol_deliver_rcu:
tcp_v4_rcv:
__inet_lookup_skb:
skb_steal_sock
The existing helper takes advantage of the fact that everything
happens in the same RCU critical section: for sockets with
SOCK_RCU_FREE set bpf_sk_assign never takes a reference.
skb_steal_sock then checks SOCK_RCU_FREE again and does sock_put
if necessary.
This approach assumes that SOCK_RCU_FREE is never set on a sk
between bpf_sk_assign and skb_steal_sock, but this invariant is
violated by unhashed UDP sockets. A new UDP socket is created
in TCP_CLOSE state but without SOCK_RCU_FREE set. That flag is only
added in udp_lib_get_port() which happens when a socket is bound.
When bpf_sk_assign was added it wasn't possible to access unhashed
UDP sockets from BPF, so this wasn't a problem. This changed
in commit 0c48eefae712 ("sock_map: Lift socket state restriction
for datagram sockets"), but the helper wasn't adjusted accordingly.
The following sequence of events will therefore lead to a refcount
leak:
1. Add socket(AF_INET, SOCK_DGRAM) to a sockmap.
2. Pull socket out of sockmap and bpf_sk_assign it. Since
SOCK_RCU_FREE is not set we increment the refcount.
3. bind() or connect() the socket, setting SOCK_RCU_FREE.
4. skb_steal_sock will now set refcounted = false due to
SOCK_RCU_FREE.
5. tcp_v4_rcv() skips sock_put().
Fix the problem by rejecting unhashed sockets in bpf_sk_assign().
This matches the behaviour of __inet_lookup_skb which is ultimately
the goal of bpf_sk_assign().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw88: delete timer and free skb queue when unloading
Fix possible crash and memory leak on driver unload by deleting
TX purge timer and freeing C2H queue in 'rtw_core_deinit()',
shrink critical section in the latter by freeing COEX queue
out of TX report lock scope.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
bpf, cpumap: Make sure kthread is running before map update returns
The following warning was reported when running stress-mode enabled
xdp_redirect_cpu with some RT threads:
------------[ cut here ]------------
WARNING: CPU: 4 PID: 65 at kernel/bpf/cpumap.c:135
CPU: 4 PID: 65 Comm: kworker/4:1 Not tainted 6.5.0-rc2+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
Workqueue: events cpu_map_kthread_stop
RIP: 0010:put_cpu_map_entry+0xda/0x220
......
Call Trace:
<TASK>
? show_regs+0x65/0x70
? __warn+0xa5/0x240
......
? put_cpu_map_entry+0xda/0x220
cpu_map_kthread_stop+0x41/0x60
process_one_work+0x6b0/0xb80
worker_thread+0x96/0x720
kthread+0x1a5/0x1f0
ret_from_fork+0x3a/0x70
ret_from_fork_asm+0x1b/0x30
</TASK>
The root cause is the same as commit 436901649731 ("bpf: cpumap: Fix memory
leak in cpu_map_update_elem"). The kthread is stopped prematurely by
kthread_stop() in cpu_map_kthread_stop(), and kthread() doesn't call
cpu_map_kthread_run() at all but XDP program has already queued some
frames or skbs into ptr_ring. So when __cpu_map_ring_cleanup() checks
the ptr_ring, it will find it was not emptied and report a warning.
An alternative fix is to use __cpu_map_ring_cleanup() to drop these
pending frames or skbs when kthread_stop() returns -EINTR, but it may
confuse the user, because these frames or skbs have been handled
correctly by XDP program. So instead of dropping these frames or skbs,
just make sure the per-cpu kthread is running before
__cpu_map_entry_alloc() returns.
After apply the fix, the error handle for kthread_stop() will be
unnecessary because it will always return 0, so just remove it.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-10-04