Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
openvswitch: vport: fix self-deadlock on release of tunnel ports
vports are used concurrently and protected by RCU, so netdev_put()
must happen after the RCU grace period. So, either in an RCU call or
after the synchronize_net(). The rtnl_delete_link() must happen under
RTNL and so can't be executed in RCU context. Calling synchronize_net()
while holding RTNL is not a good idea for performance and system
stability under load in general, so calling netdev_put() in RCU call
is the right solution here.
However,
when the device is deleted, rtnl_unlock() will call netdev_run_todo()
and block until all the references are gone. In the current code this
means that we never reach the call_rcu() and the vport is never freed
and the reference is never released, causing a self-deadlock on device
removal.
Fix that by moving the rcu_call() before the rtnl_unlock(), so the
scheduled RCU callback will be executed when synchronize_net() is
called from the rtnl_unlock()->netdev_run_todo() while the RTNL itself
is already released.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: use safe list iteration in radar detect work
The call to ieee80211_dfs_cac_cancel can cause the iterated chanctx to
be freed and removed from the list. Guard against this to avoid a
slab-use-after-free error.
CVSS Score
8.8
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
usb: usblp: fix uninitialized heap leak via LPGETSTATUS ioctl
Just like in a previous problem in this driver, usblp_ctrl_msg() will
collapse the usb_control_msg() return value to 0/-errno, discarding the
actual number of bytes transferred.
Ideally that short command should be detected and error out, but many
printers are known to send "incorrect" responses back so we can't just
do that.
statusbuf is kmalloc(8) at probe time and never filled before the first
LPGETSTATUS ioctl.
usblp_read_status() requests 1 byte. If a malicious printer responds
with zero bytes, *statusbuf is one byte of stale kmalloc heap,
sign-extended into the local int status, which the LPGETSTATUS path then
copy_to_user()s directly to the ioctl caller.
Fix this all by just zapping out the memory buffer when allocated at
probe time. If a later call does a short read, the data will be
identical to what the device sent it the last time, so there is no
"leak" of information happening.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
mptcp: fix scheduling with atomic in timestamp sockopt
Using lock_sock_fast() (atomic context) around sock_set_timestamp()
and sock_set_timestamping() is unsafe, as both helpers can sleep.
Replace lock_sock_fast() with sleepable lock_sock()/release_sock()
to avoid scheduling while atomic panic.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
hfsplus: fix uninit-value by validating catalog record size
Syzbot reported a KMSAN uninit-value issue in hfsplus_strcasecmp(). The
root cause is that hfs_brec_read() doesn't validate that the on-disk
record size matches the expected size for the record type being read.
When mounting a corrupted filesystem, hfs_brec_read() may read less data
than expected. For example, when reading a catalog thread record, the
debug output showed:
HFSPLUS_BREC_READ: rec_len=520, fd->entrylength=26
HFSPLUS_BREC_READ: WARNING - entrylength (26) < rec_len (520) - PARTIAL READ!
hfs_brec_read() only validates that entrylength is not greater than the
buffer size, but doesn't check if it's less than expected. It successfully
reads 26 bytes into a 520-byte structure and returns success, leaving 494
bytes uninitialized.
This uninitialized data in tmp.thread.nodeName then gets copied by
hfsplus_cat_build_key_uni() and used by hfsplus_strcasecmp(), triggering
the KMSAN warning when the uninitialized bytes are used as array indices
in case_fold().
Fix by introducing hfsplus_brec_read_cat() wrapper that:
1. Calls hfs_brec_read() to read the data
2. Validates the record size based on the type field:
- Fixed size for folder and file records
- Variable size for thread records (depends on string length)
3. Returns -EIO if size doesn't match expected
For thread records, check against HFSPLUS_MIN_THREAD_SZ before reading
nodeName.length to avoid reading uninitialized data at call sites that
don't zero-initialize the entry structure.
Also initialize the tmp variable in hfsplus_find_cat() as defensive
programming to ensure no uninitialized data even if validation is
bypassed.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
mptcp: pm: ADD_ADDR rtx: free sk if last
When an ADD_ADDR is retransmitted, the sk is held in sk_reset_timer(),
and released at the end.
If at that moment, it was the last reference being held, the sk would
not be freed. sock_put() should then be called instead of __sock_put().
But that's not enough: if it is the last reference, sock_put() will call
sk_free(), which will end up calling sk_stop_timer_sync() on the same
timer, and waiting indefinitely to finish. So it is needed to mark that
the timer is done at the end of the timer handler when it has not been
rescheduled, not to call sk_stop_timer_sync() on "itself".
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
riscv: kvm: fix vector context allocation leak
When the second kzalloc (host_context.vector.datap) fails in
kvm_riscv_vcpu_alloc_vector_context, the first allocation
(guest_context.vector.datap) is leaked. Free it before returning.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
ipv6: xfrm6: release dst on error in xfrm6_rcv_encap()
xfrm6_rcv_encap() performs an IPv6 route lookup when the skb does not
already have a dst attached. ip6_route_input_lookup() returns a
referenced dst entry even when the lookup resolves to an error route.
If dst->error is set, xfrm6_rcv_encap() drops the skb without attaching
the dst to the skb and without releasing the reference returned by the
lookup. Repeated packets hitting this path therefore leak dst entries.
Release the dst before jumping to the drop path.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
exit: prevent preemption of oopsing TASK_DEAD task
When an already-exiting task oopses, make_task_dead() currently calls
do_task_dead() with preemption enabled. That is forbidden:
do_task_dead() calls __schedule(), which has a comment saying "WARNING:
must be called with preemption disabled!".
If an oopsing task is preempted in do_task_dead(), between becoming
TASK_DEAD and entering the scheduler explicitly, bad things happen:
finish_task_switch() assumes that once the scheduler has switched away
from a TASK_DEAD task, the task can never run again and its stack is no
longer needed; but that assumption apparently doesn't hold if the dead
task was preempted (the SM_PREEMPT case).
This means that the scheduler ends up repeatedly dropping references on
the dead task's stack, which can lead to use-after-free or double-free
of the entire task stack; in other words, two tasks can end up running
on the same stack, resulting in various kinds of memory corruption.
(This does not just affect "recursively oopsing" tasks; it is enough to
oops once during task exit, for example in a file_operations::release
handler)
CVSS Score
7.8
EPSS Score
0.0
Published
2026-05-28
In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Read scx_root under scx_cgroup_ops_rwsem in cgroup setters
scx_group_set_{weight,idle,bandwidth}() cache scx_root before acquiring
scx_cgroup_ops_rwsem, so the pointer can be stale by the time the op runs.
If the loaded scheduler is disabled and freed (via RCU work) and another is
enabled between the naked load and the rwsem acquire, the reader sees
scx_cgroup_enabled=true (the new scheduler's) but dereferences the freed one
- UAF on SCX_HAS_OP(sch, ...) / SCX_CALL_OP(sch, ...).
scx_cgroup_enabled is toggled only under scx_cgroup_ops_rwsem write
(scx_cgroup_{init,exit}), so reading scx_root inside the rwsem read section
correlates @sch with the enabled snapshot.
CVSS Score
7.0
EPSS Score
0.0
Published
2026-05-28