Security Vulnerabilities - CVEs Published In April 2025
In the Linux kernel, the following vulnerability has been resolved:
fs/9p: fix NULL pointer dereference on mkdir
When a 9p tree was mounted with option 'posixacl', parent directory had a
default ACL set for its subdirectories, e.g.:
setfacl -m default:group:simpsons:rwx parentdir
then creating a subdirectory crashed 9p client, as v9fs_fid_add() call in
function v9fs_vfs_mkdir_dotl() sets the passed 'fid' pointer to NULL
(since dafbe689736) even though the subsequent v9fs_set_create_acl() call
expects a valid non-NULL 'fid' pointer:
[ 37.273191] BUG: kernel NULL pointer dereference, address: 0000000000000000
...
[ 37.322338] Call Trace:
[ 37.323043] <TASK>
[ 37.323621] ? __die (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:434)
[ 37.324448] ? page_fault_oops (arch/x86/mm/fault.c:714)
[ 37.325532] ? search_module_extables (kernel/module/main.c:3733)
[ 37.326742] ? p9_client_walk (net/9p/client.c:1165) 9pnet
[ 37.328006] ? search_bpf_extables (kernel/bpf/core.c:804)
[ 37.329142] ? exc_page_fault (./arch/x86/include/asm/paravirt.h:686 arch/x86/mm/fault.c:1488 arch/x86/mm/fault.c:1538)
[ 37.330196] ? asm_exc_page_fault (./arch/x86/include/asm/idtentry.h:574)
[ 37.331330] ? p9_client_walk (net/9p/client.c:1165) 9pnet
[ 37.332562] ? v9fs_fid_xattr_get (fs/9p/xattr.c:30) 9p
[ 37.333824] v9fs_fid_xattr_set (fs/9p/fid.h:23 fs/9p/xattr.c:121) 9p
[ 37.335077] v9fs_set_acl (fs/9p/acl.c:276) 9p
[ 37.336112] v9fs_set_create_acl (fs/9p/acl.c:307) 9p
[ 37.337326] v9fs_vfs_mkdir_dotl (fs/9p/vfs_inode_dotl.c:411) 9p
[ 37.338590] vfs_mkdir (fs/namei.c:4313)
[ 37.339535] do_mkdirat (fs/namei.c:4336)
[ 37.340465] __x64_sys_mkdir (fs/namei.c:4354)
[ 37.341455] do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
[ 37.342447] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
Fix this by simply swapping the sequence of these two calls in
v9fs_vfs_mkdir_dotl(), i.e. calling v9fs_set_create_acl() before
v9fs_fid_add().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
spufs: fix a leak in spufs_create_context()
Leak fixes back in 2008 missed one case - if we are trying to set affinity
and spufs_mkdir() fails, we need to drop the reference to neighbor.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
spufs: fix gang directory lifetimes
prior to "[POWERPC] spufs: Fix gang destroy leaks" we used to have
a problem with gang lifetimes - creation of a gang returns opened
gang directory, which normally gets removed when that gets closed,
but if somebody has created a context belonging to that gang and
kept it alive until the gang got closed, removal failed and we
ended up with a leak.
Unfortunately, it had been fixed the wrong way. Dentry of gang
directory was no longer pinned, and rmdir on close was gone.
One problem was that failure of open kept calling simple_rmdir()
as cleanup, which meant an unbalanced dput(). Another bug was
in the success case - gang creation incremented link count on
root directory, but that was no longer undone when gang got
destroyed.
Fix consists of
* reverting the commit in question
* adding a counter to gang, protected by ->i_rwsem
of gang directory inode.
* having it set to 1 at creation time, dropped
in both spufs_dir_close() and spufs_gang_close() and bumped
in spufs_create_context(), provided that it's not 0.
* using simple_recursive_removal() to take the gang
directory out when counter reaches zero.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
spufs: fix a leak on spufs_new_file() failure
It's called from spufs_fill_dir(), and caller of that will do
spufs_rmdir() in case of failure. That does remove everything
we'd managed to create, but... the problem dentry is still
negative. IOW, it needs to be explicitly dropped.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix r_count dec/increment mismatch
r_count is only increased when there is an oplock break wait,
so r_count inc/decrement are not paired. This can cause r_count
to become negative, which can lead to a problem where the ksmbd
thread does not terminate.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
rtnetlink: Allocate vfinfo size for VF GUIDs when supported
Commit 30aad41721e0 ("net/core: Add support for getting VF GUIDs")
added support for getting VF port and node GUIDs in netlink ifinfo
messages, but their size was not taken into consideration in the
function that allocates the netlink message, causing the following
warning when a netlink message is filled with many VF port and node
GUIDs:
# echo 64 > /sys/bus/pci/devices/0000\:08\:00.0/sriov_numvfs
# ip link show dev ib0
RTNETLINK answers: Message too long
Cannot send link get request: Message too long
Kernel warning:
------------[ cut here ]------------
WARNING: CPU: 2 PID: 1930 at net/core/rtnetlink.c:4151 rtnl_getlink+0x586/0x5a0
Modules linked in: xt_conntrack xt_MASQUERADE nfnetlink xt_addrtype iptable_nat nf_nat br_netfilter overlay mlx5_ib macsec mlx5_core tls rpcrdma rdma_ucm ib_uverbs ib_iser libiscsi scsi_transport_iscsi ib_umad rdma_cm iw_cm ib_ipoib fuse ib_cm ib_core
CPU: 2 UID: 0 PID: 1930 Comm: ip Not tainted 6.14.0-rc2+ #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:rtnl_getlink+0x586/0x5a0
Code: cb 82 e8 3d af 0a 00 4d 85 ff 0f 84 08 ff ff ff 4c 89 ff 41 be ea ff ff ff e8 66 63 5b ff 49 c7 07 80 4f cb 82 e9 36 fc ff ff <0f> 0b e9 16 fe ff ff e8 de a0 56 00 66 66 2e 0f 1f 84 00 00 00 00
RSP: 0018:ffff888113557348 EFLAGS: 00010246
RAX: 00000000ffffffa6 RBX: ffff88817e87aa34 RCX: dffffc0000000000
RDX: 0000000000000003 RSI: 0000000000000000 RDI: ffff88817e87afb8
RBP: 0000000000000009 R08: ffffffff821f44aa R09: 0000000000000000
R10: ffff8881260f79a8 R11: ffff88817e87af00 R12: ffff88817e87aa00
R13: ffffffff8563d300 R14: 00000000ffffffa6 R15: 00000000ffffffff
FS: 00007f63a5dbf280(0000) GS:ffff88881ee00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f63a5ba4493 CR3: 00000001700fe002 CR4: 0000000000772eb0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
? __warn+0xa5/0x230
? rtnl_getlink+0x586/0x5a0
? report_bug+0x22d/0x240
? handle_bug+0x53/0xa0
? exc_invalid_op+0x14/0x50
? asm_exc_invalid_op+0x16/0x20
? skb_trim+0x6a/0x80
? rtnl_getlink+0x586/0x5a0
? __pfx_rtnl_getlink+0x10/0x10
? rtnetlink_rcv_msg+0x1e5/0x860
? __pfx___mutex_lock+0x10/0x10
? rcu_is_watching+0x34/0x60
? __pfx_lock_acquire+0x10/0x10
? stack_trace_save+0x90/0xd0
? filter_irq_stacks+0x1d/0x70
? kasan_save_stack+0x30/0x40
? kasan_save_stack+0x20/0x40
? kasan_save_track+0x10/0x30
rtnetlink_rcv_msg+0x21c/0x860
? entry_SYSCALL_64_after_hwframe+0x76/0x7e
? __pfx_rtnetlink_rcv_msg+0x10/0x10
? arch_stack_walk+0x9e/0xf0
? rcu_is_watching+0x34/0x60
? lock_acquire+0xd5/0x410
? rcu_is_watching+0x34/0x60
netlink_rcv_skb+0xe0/0x210
? __pfx_rtnetlink_rcv_msg+0x10/0x10
? __pfx_netlink_rcv_skb+0x10/0x10
? rcu_is_watching+0x34/0x60
? __pfx___netlink_lookup+0x10/0x10
? lock_release+0x62/0x200
? netlink_deliver_tap+0xfd/0x290
? rcu_is_watching+0x34/0x60
? lock_release+0x62/0x200
? netlink_deliver_tap+0x95/0x290
netlink_unicast+0x31f/0x480
? __pfx_netlink_unicast+0x10/0x10
? rcu_is_watching+0x34/0x60
? lock_acquire+0xd5/0x410
netlink_sendmsg+0x369/0x660
? lock_release+0x62/0x200
? __pfx_netlink_sendmsg+0x10/0x10
? import_ubuf+0xb9/0xf0
? __import_iovec+0x254/0x2b0
? lock_release+0x62/0x200
? __pfx_netlink_sendmsg+0x10/0x10
____sys_sendmsg+0x559/0x5a0
? __pfx_____sys_sendmsg+0x10/0x10
? __pfx_copy_msghdr_from_user+0x10/0x10
? rcu_is_watching+0x34/0x60
? do_read_fault+0x213/0x4a0
? rcu_is_watching+0x34/0x60
___sys_sendmsg+0xe4/0x150
? __pfx____sys_sendmsg+0x10/0x10
? do_fault+0x2cc/0x6f0
? handle_pte_fault+0x2e3/0x3d0
? __pfx_handle_pte_fault+0x10/0x10
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
exfat: fix missing shutdown check
xfstests generic/730 test failed because after deleting the device
that still had dirty data, the file could still be read without
returning an error. The reason is the missing shutdown check in
->read_iter.
I also noticed that shutdown checks were missing from ->write_iter,
->splice_read, and ->mmap. This commit adds shutdown checks to all
of them.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
Revert "smb: client: fix TCP timers deadlock after rmmod"
This reverts commit e9f2517a3e18a54a3943c098d2226b245d488801.
Commit e9f2517a3e18 ("smb: client: fix TCP timers deadlock after
rmmod") is intended to fix a null-ptr-deref in LOCKDEP, which is
mentioned as CVE-2024-54680, but is actually did not fix anything;
The issue can be reproduced on top of it. [0]
Also, it reverted the change by commit ef7134c7fc48 ("smb: client:
Fix use-after-free of network namespace.") and introduced a real
issue by reviving the kernel TCP socket.
When a reconnect happens for a CIFS connection, the socket state
transitions to FIN_WAIT_1. Then, inet_csk_clear_xmit_timers_sync()
in tcp_close() stops all timers for the socket.
If an incoming FIN packet is lost, the socket will stay at FIN_WAIT_1
forever, and such sockets could be leaked up to net.ipv4.tcp_max_orphans.
Usually, FIN can be retransmitted by the peer, but if the peer aborts
the connection, the issue comes into reality.
I warned about this privately by pointing out the exact report [1],
but the bogus fix was finally merged.
So, we should not stop the timers to finally kill the connection on
our side in that case, meaning we must not use a kernel socket for
TCP whose sk->sk_net_refcnt is 0.
The kernel socket does not have a reference to its netns to make it
possible to tear down netns without cleaning up every resource in it.
For example, tunnel devices use a UDP socket internally, but we can
destroy netns without removing such devices and let it complete
during exit. Otherwise, netns would be leaked when the last application
died.
However, this is problematic for TCP sockets because TCP has timers to
close the connection gracefully even after the socket is close()d. The
lifetime of the socket and its netns is different from the lifetime of
the underlying connection.
If the socket user does not maintain the netns lifetime, the timer could
be fired after the socket is close()d and its netns is freed up, resulting
in use-after-free.
Actually, we have seen so many similar issues and converted such sockets
to have a reference to netns.
That's why I converted the CIFS client socket to have a reference to
netns (sk->sk_net_refcnt == 1), which is somehow mentioned as out-of-scope
of CIFS and technically wrong in e9f2517a3e18, but **is in-scope and right
fix**.
Regarding the LOCKDEP issue, we can prevent the module unload by
bumping the module refcount when switching the LOCKDDEP key in
sock_lock_init_class_and_name(). [2]
For a while, let's revert the bogus fix.
Note that now we can use sk_net_refcnt_upgrade() for the socket
conversion, but I'll do so later separately to make backport easy.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: don't unregister hook when table is dormant
When nf_tables_updchain encounters an error, hook registration needs to
be rolled back.
This should only be done if the hook has been registered, which won't
happen when the table is flagged as dormant (inactive).
Just move the assignment into the registration block.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
idpf: fix adapter NULL pointer dereference on reboot
With SRIOV enabled, idpf ends up calling into idpf_remove() twice.
First via idpf_shutdown() and then again when idpf_remove() calls into
sriov_disable(), because the VF devices use the idpf driver, hence the
same remove routine. When that happens, it is possible for the adapter
to be NULL from the first call to idpf_remove(), leading to a NULL
pointer dereference.
echo 1 > /sys/class/net/<netif>/device/sriov_numvfs
reboot
BUG: kernel NULL pointer dereference, address: 0000000000000020
...
RIP: 0010:idpf_remove+0x22/0x1f0 [idpf]
...
? idpf_remove+0x22/0x1f0 [idpf]
? idpf_remove+0x1e4/0x1f0 [idpf]
pci_device_remove+0x3f/0xb0
device_release_driver_internal+0x19f/0x200
pci_stop_bus_device+0x6d/0x90
pci_stop_and_remove_bus_device+0x12/0x20
pci_iov_remove_virtfn+0xbe/0x120
sriov_disable+0x34/0xe0
idpf_sriov_configure+0x58/0x140 [idpf]
idpf_remove+0x1b9/0x1f0 [idpf]
idpf_shutdown+0x12/0x30 [idpf]
pci_device_shutdown+0x35/0x60
device_shutdown+0x156/0x200
...
Replace the direct idpf_remove() call in idpf_shutdown() with
idpf_vc_core_deinit() and idpf_deinit_dflt_mbx(), which perform
the bulk of the cleanup, such as stopping the init task, freeing IRQs,
destroying the vports and freeing the mailbox. This avoids the calls to
sriov_disable() in addition to a small netdev cleanup, and destroying
workqueues, which don't seem to be required on shutdown.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-04-16