Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: properly validate the data in rtw_get_ie_ex()
Just like in commit 154828bf9559 ("staging: rtl8723bs: fix out-of-bounds
read in rtw_get_ie() parser"), we don't trust the data in the frame so
we should check the length better before acting on it
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
mm/damon/core: clear walk_control on inactive context in damos_walk()
damos_walk() sets ctx->walk_control to the caller-provided control
structure before checking whether the context is running. If the context
is inactive (damon_is_running() returns false), the function returns
-EINVAL without clearing ctx->walk_control. This leaves a dangling
pointer to a stack-allocated structure that will be freed when the caller
returns.
This is structurally identical to the bug fixed in commit f9132fbc2e83
("mm/damon/core: remove call_control in inactive contexts") for
damon_call(), which had the same pattern of linking a control object and
returning an error without unlinking it.
The dangling walk_control pointer can cause:
1. Use-after-free if the context is later started and kdamond
dereferences ctx->walk_control (e.g., in damos_walk_cancel()
which writes to control->canceled and calls complete())
2. Permanent -EBUSY from subsequent damos_walk() calls, since the
stale pointer is non-NULL
Nonetheless, the real user impact is quite restrictive. The
use-after-free is impossible because there is no damos_walk() callers who
starts the context later. The permanent -EBUSY can actually confuse
users, as DAMON is not running. But the symptom is kept only while the
context is turned off. Turning it on again will make DAMON internally
uses a newly generated damon_ctx object that doesn't have the invalid
damos_walk_control pointer, so everything will work fine again.
Fix this by clearing ctx->walk_control under walk_control_lock before
returning -EINVAL, mirroring the fix pattern from f9132fbc2e83.
CVSS Score
7.8
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
mm: memfd_luo: always dirty all folios
A dirty folio is one which has been written to. A clean folio is its
opposite. Since a clean folio has no user data, it can be freed under
memory pressure.
memfd preservation with LUO saves the flag at preserve(). This is
problematic. The folio might get dirtied later. Saving it at freeze()
also doesn't work, since the dirty bit from PTE is normally synced at
unmap and there might still be mappings of the file at freeze().
To see why this is a problem, say a folio is clean at preserve, but gets
dirtied later. The serialized state of the folio will mark it as clean.
After retrieve, the next kernel will see the folio as clean and might try
to reclaim it under memory pressure. This will result in losing user
data.
Mark all folios of the file as dirty, and always set the
MEMFD_LUO_FOLIO_DIRTY flag. This comes with the side effect of making all
clean folios un-reclaimable. This is a cost that has to be paid for
participants of live update. It is not expected to be a common use case
to preserve a lot of clean folios anyway.
Since the value of pfolio->flags is a constant now, drop the flags
variable and set it directly.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
nstree: tighten permission checks for listing
Even privileged services should not necessarily be able to see other
privileged service's namespaces so they can't leak information to each
other. Use may_see_all_namespaces() helper that centralizes this policy
until the nstree adapts.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
nsfs: tighten permission checks for handle opening
Even privileged services should not necessarily be able to see other
privileged service's namespaces so they can't leak information to each
other. Use may_see_all_namespaces() helper that centralizes this policy
until the nstree adapts.
CVSS Score
8.8
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Fix starvation of scx_enable() under fair-class saturation
During scx_enable(), the READY -> ENABLED task switching loop changes the
calling thread's sched_class from fair to ext. Since fair has higher
priority than ext, saturating fair-class workloads can indefinitely starve
the enable thread, hanging the system. This was introduced when the enable
path switched from preempt_disable() to scx_bypass() which doesn't protect
against fair-class starvation. Note that the original preempt_disable()
protection wasn't complete either - in partial switch modes, the calling
thread could still be starved after preempt_enable() as it may have been
switched to ext class.
Fix it by offloading the enable body to a dedicated system-wide RT
(SCHED_FIFO) kthread which cannot be starved by either fair or ext class
tasks. scx_enable() lazily creates the kthread on first use and passes the
ops pointer through a struct scx_enable_cmd containing the kthread_work,
then synchronously waits for completion.
The workfn runs on a different kthread from sch->helper (which runs
disable_work), so it can safely flush disable_work on the error path
without deadlock.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix chunk map leak in btrfs_map_block() after btrfs_chunk_map_num_copies()
Fix a chunk map leak in btrfs_map_block(): if we return early with -EINVAL,
we're not freeing the chunk map that we've just looked up.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
nfsd: Fix cred ref leak in nfsd_nl_listener_set_doit().
nfsd_nl_listener_set_doit() uses get_current_cred() without
put_cred().
As we can see from other callers, svc_xprt_create_from_sa()
does not require the extra refcount.
nfsd_nl_listener_set_doit() is always in the process context,
sendmsg(), and current->cred does not go away.
Let's use current_cred() in nfsd_nl_listener_set_doit().
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
drm/xe/sync: Cleanup partially initialized sync on parse failure
xe_sync_entry_parse() can allocate references (syncobj, fence, chain fence,
or user fence) before hitting a later failure path. Several of those paths
returned directly, leaving partially initialized state and leaking refs.
Route these error paths through a common free_sync label and call
xe_sync_entry_cleanup(sync) before returning the error.
(cherry picked from commit f939bdd9207a5d1fc55cced5459858480686ce22)
CVSS Score
5.5
EPSS Score
0.0
Published
2026-05-08
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close()
opinfo pointer obtained via rcu_dereference(fp->f_opinfo) is being
accessed after rcu_read_unlock() has been called. This creates a
race condition where the memory could be freed by a concurrent
writer between the unlock and the subsequent pointer dereferences
(opinfo->is_lease, etc.), leading to a use-after-free.
CVSS Score
9.8
EPSS Score
0.001
Published
2026-05-08