| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
mlxsw: spectrum_flower: Fix port range register leak in tmplt_create()
mlxsw_sp_flower_tmplt_create() parses a flow_cls_offload template
into a stack-local struct mlxsw_sp_acl_rule_info purely to compute
rulei.values.elusage. Parsing can acquire port range registers via
mlxsw_sp_flower_parse_ports_range(), but since this rulei never goes
through mlxsw_sp_acl_rulei_destroy(), those registers were never
released, including through chain template deletion.
Factor out of mlxsw_sp_acl_rulei_destroy() the code to actually
release the necessary resources and call from
mlxsw_sp_flower_tmplt_create() to plug the leak.
The issue was found during a review of Wentao Liang's patch referenced
below. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/imagination: Fix reference and vm_bo handling in remap()
When a map overlaps part of an existing mapping, pvr_vm_gpuva_remap()
splits the mapping into prev/next parts covering what the request did
not take, instead of creating something new. It gets two things wrong.
- A GEM reference is taken for each part but it's never needed and never
dropped, so it leaks one reference per split (remap-next-in-2m in
tests/imagination/pvr_vm_map.c):
CRITICAL: 33558528 bytes of shmem still held after close
- The parts still belong to the original object being split, but
pvr_vm_gpuva_remap() links them to ctx->gpuvm_bo, the new object's
vm_bo:
prev_va --obj--> BO_A BO_B <--obj-- vm_bo (ctx->gpuvm_bo)
\___________link___________/ (mismatch: BO_A != BO_B)
drm_gpuva_link() catches the mismatch:
WARNING: drivers/gpu/drm/drm_gpuvm.c:2108 at drm_gpuva_link+0x2ec/0x310
drm_WARN_ON(obj != vm_bo->obj)
Call trace:
drm_gpuva_link
pvr_vm_gpuva_remap
__drm_gpuvm_sm_map
pvr_vm_map
pvr_ioctl_vm_map
Link them to op->remap.unmap->va->vm_bo instead.
The locking of the GPUVA lists of the other objects touched by a split is
not addressed here; it is handled by switching the GPUVM to immediate
mode. |
| In the Linux kernel, the following vulnerability has been resolved:
riscv: ptrace: Zero-initialize regset buffers before copyin
user_regset_copyin() only copies `count` bytes, so a PTRACE_SETREGSET
request with a short iov_len leaves the rest of the stack buffer
uninitialized. In riscv_vr_set() that garbage is validated and copied
into the target's vstate, and in riscv_cfi_set() it can be stored as
the target's shadow stack pointer. Zero both buffers, as the get path
already does. |
| In the Linux kernel, the following vulnerability has been resolved:
pfcp: make sure the SEID is linear before reading it
pfcp_encap_recv() only makes sure that the UDP header and the 4 byte
PFCP header are in the linear area. When the S flag is set,
pfcp_session_recv() then reads the 8 byte SEID that follows, which is
not covered by the pskb_may_pull() check.
A short PFCP packet with the S flag set, or one whose session header
lies in a fragment, therefore makes pfcp_session_recv() read beyond the
end of the packet data, and whatever it finds there is stored in the
tunnel metadata that flower later classifies on.
Pull up to the end of the SEID before reading it, and drop packets
that are too short to contain it. Reload the header pointer afterwards
since pskb_may_pull() may reallocate the skb head.
Use offsetofend() rather than sizeof(struct pfcphdr_session): the
structure is not packed, so its size is 16 bytes because of the
alignment of the __be64 member, while the header on the wire is only 12
bytes, and valid session messages would be dropped. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: free iov when btrfs_uring_read_extent() fails
After btrfs_uring_read_extent(), the caller always jumped to out_acct.
That skips kfree(data->iov), which is only correct for -EIOCBQUEUED
where the deferred path owns the iov. On failure, fall through to
out_free instead. |
| In the Linux kernel, the following vulnerability has been resolved:
namespace: keep covered mounts covered in OPEN_TREE_NAMESPACE
open_tree(OPEN_TREE_NAMESPACE) creates a new mount namespace from a
copy of the tree at the given path. The caller needs to be privileged
over its current user namespace because the new mount namespace will be
owned by it. It doesn't need to be privileged over the mount namespace
the tree is copied from. An unprivileged user just needs to create a
user namespace first.
The copy follows the rules of a detached bind mount. Without
AT_RECURSIVE only the mount itself is cloned and its children are left
out. With AT_RECURSIVE unbindable mounts are skipped. Both is fine when
the caller has privileges over the source mount namespace because it
could unmount those mounts anyway. Not so for an unprivileged user in
that mount namespace. For them a mount namespace copy is what unshare()
does. copy_mnt_ns() copies everything including unbindable mounts and
lock_mnt_tree() makes sure nothing can be unmounted in the copy. Nothing
that was covered gets revealed.
create_new_namespace() only does the locking and so the covered content
is right there in the new mount namespace:
# mount -t tmpfs none /tmp/otn; mkdir /tmp/otn/covered
# echo hidden > /tmp/otn/covered/under.txt
# mount -t tmpfs none /tmp/otn/covered
uid 1000, after unshare(CLONE_NEWUSER):
fd = open_tree(AT_FDCWD, "/tmp/otn", OPEN_TREE_NAMESPACE);
setns(fd, CLONE_NEWNS);
open("/covered/under.txt", O_RDONLY) -> "hidden"
Covering paths with mounts is how container runtimes mask parts of
/proc and /sys and how admins hide things.
When the caller's user namespace doesn't own the source mount namespace
copy the way unshare() does and refuse a non-recursive copy of a mount
that has anything mounted below the requested directory and copy
unbindable mounts in a recursive copy. A caller that is privileged over
the source mount namespace sees no change. |
| In the Linux kernel, the following vulnerability has been resolved:
namespace: check a recursive bind mount for mount namespace loops
do_loopback() refuses to bind mount the file of a mount namespace that
is as old as the caller's or older because a mount namespace that holds
a mount of its own file, or of an ancestor's, would cause a cycle. But
it only checks the dentry the bind mount starts from. With MS_REC
everything below it is copied and do_loopback() passes
CL_COPY_MNT_NS_FILE so mount namespace files below the source are
copied.
That's fine for a source in the caller's own mount namespace. Every
mount namespace file in there passed the same check when it was
bind-mounted. It isn't fine for a source in another mount namespace.
may_copy_tree() accepts a bind mount of any nsfs or pidfs file no matter
what mount namespace it lives in so that /proc/<pid>/ns/<ns> and pidfds
can be bind mounted. If we create a bind-mount stack of mount namespaces
file descriptors the kernel will copy them irrespective of their
ancestoral relationship to the mount namespace in question:
151 146 0:7 net:[4026531833] /tmp/nrc/y rw - nsfs nsfs rw
152 151 0:7 mnt:[4026532293] /tmp/nrc/y rw - nsfs nsfs rw
Mount 152 is a mount of the mount namespace file of mount namespace
4026532293 inside mount namespace 4026532293. That namespace and every
mount in it are leaked... All it takes is a process in an older mount
namespace that stacks the file and repeating it leaks without limit:
after control: Shmem: 380 kB
child: mount(/proc/self/fd/6, MS_BIND|MS_REC): ok
after cycle: Shmem: 65916 kB
do_move_mount() runs check_for_nsfs_mounts() over a detached tree for
exactly that reason. Do the same for the copy before it is grafted. |
| In the Linux kernel, the following vulnerability has been resolved:
bonding: fix the program leak when XDP is replaced
We need to release the reference on the old BPF prog, whether
we are going to no-prog, or replacing the prog with another.
Spotted by AI while running tests for the propagation series
(leaked programs were accumulating). Selftest will come in
the net-next series to avoid conflicts. |
| In the Linux kernel, the following vulnerability has been resolved:
cgroup/cpuset: Don't access cpuset_cgrp_subsys.root in is_in_v2_mode()
After seeing the patch [1] to guard is_in_v2_mode() with RCU, it makes
me realize that is_in_v2_mode() may be called in a context where a new
cgroup filesystem is being rebound with stale cpuset_cgrp_subsys.root
pointer. Avoid this potential UaF situation by adding a new cpuset_v2_mode
flag which is set when the cpuset_v2_mode mount option is used. This
flag is written into only when cpuset_bind() is being called with a
stable cpuset_cgrp_subsys.root value. The is_in_v2_mode() helper is
modified to read the new cpuset_v2_mode flag instead of accessing
cpuset_cgrp_subsys.root directly.
[1] https://lore.kernel.org/lkml/20260929084124.626693-2-arighi@nvidia.com |
| In the Linux kernel, the following vulnerability has been resolved:
drm/bridge: Fix unlocked list_del in drm_bridge_add()
When re-adding a bridge that was previously removed, drm_bridge_add()
drops it from bridge_lingering_list without holding bridge_lock.
Both bridge_list and bridge_lingering_list are protected by bridge_lock,
as they are concurrently modified by drm_bridge_remove() and
__drm_bridge_free(), and walked by the debugfs 'bridges' file. Running
the list_empty() test and the list_del_init() outside of the lock may
therefore corrupt either list.
Perform both under bridge_lock. |
| In the Linux kernel, the following vulnerability has been resolved:
namei: don't reveal overmounted entries in refwalk
In rcuwalk the dentry is validated before it is accepted. step_into()
step_into() rechecks d_seq and __follow_mount_rcu() rechecks mount_lock.
An entry that gets unlinked in between causes the lookup to retry and
miss.
A refwalk doesn't do this. lookup_fast() takes a reference on the hashed
dentry and simply accepts it. So an unlink that happens after the
reference was taken isn't seen by refwalk. That's fine for a simple
file. We just happened to open it before it was unlinked, no problem.
For a mountpoint and specifically a locked mountpoint it very much
isn't. The unlink detaches all mounts and then removes the name. Any
refwalk that hasn't traversed the mounts yet simply reveals the
underlying entry. It's a very narrow window but it can be hit:
reads of a covered file in 60 s, 3 walkers, ~15000 unlinks
no widening 27
that step + 200 us 3741
See the appended patch for a more reliable reproducer.
So check the entry after step_into(). unlink(), rmdir() and rename()
mark the dentry with dont_mount() before they detach the mounts and
remove the dentry.
So a dentry that is marked with DCACHE_CANT_MOUNT and is unhashed by the
time its mounts were looked at is a name that was unlinked under the
refwalk. DCACHE_CANT_MOUNT is read after the mounts were looked up and
it is set before they are detached by detach_mounts(). A refwalk that
missed the mounts will see DCACHE_CANT_MOUNT.
Plain d_unlinked() is fine. A rename takes the dentry off its hash chain
but ___d_drop() leaves d_hash.pprev set. So only __d_drop() and a rename
over the dentry unhash it. The only move that flips IS_ROOT splices in a
disconnected alias. That doesn't have DCACHE_CANT_MOUNT set.
Add the to step_into_slowpath(). ".." and LOOKUP_DOWN may legitimately
land on an unhashed directory. A refwalk that crossed onto a mount has
path.mnt different from nd->path.mnt. A dentry that a filesystem dropped
on its own (d_invalidate(), d_drop()) doesn't have the flag set and is
treated as before.
// SPDX-License-Identifier: GPL-2.0
/*
* unlink_covered: unlink a file that is a mountpoint in a detached copy of
* its mount, against walkers that open it through that copy.
*
* A is a tmpfs with the file f1 (content SECRET_F) and the plain file
* MARK_A. A' is an open_tree(OPEN_TREE_CLONE) copy of A with MARK_A bound
* on A'/f1, held through an O_PATH fd on its root once the tree fd is
* closed. Walkers open f1 through that fd while the driver unlinks A/f1,
* where nothing is mounted on it. A walker may read MARK_A or get ENOENT.
* A read of SECRET_F is a hit: the name was found after its mount was
* gone. The lockless walks use openat2(RESOLVE_CACHED).
*
* usage: unlink_covered [-t seconds] [-w walkers]
*/
#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <stdatomic.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <linux/openat2.h>
#ifndef __NR_open_tree
#define __NR_open_tree 428
#endif
#ifndef __NR_move_mount
#define __NR_move_mount 429
#endif
#ifndef __NR_openat2
#define __NR_openat2 437
#endif
#ifndef OPEN_TREE_CLONE
#define OPEN_TREE_CLONE 1
#endif
#ifndef OPEN_TREE_CLOEXEC
#define OPEN_TREE_CLOEXEC O_CLOEXEC
#endif
#ifndef MOVE_MOUNT_F_EMPTY_PATH
#define MOVE_MOUNT_F_EMPTY_PATH 0x00000004
#endif
#define WORK "/tmp/uc"
#define ADIR WORK "/A"
static int duration = 60, nwalkers = 3;
static atomic_int stop, writer_waiting;
static pthread_rwlock_t cur_lock = PTHREAD_RWLOCK_INITIALIZER;
static int cur_fd = -1; /* the root of A', -1 while there is none */
static atomic_long n_unlink, n_walk, n_mark, n_enoent, n_othe
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
namespace: remove the fsnotify marks of a mount namespace in process context
mnt_ns_release() drops the last passive reference of a mount namespace
and removes its fanotify marks via fsnotify_mntns_delete(). That takes
the mutex of every group with a mark on the namespace and the spinlock
of the connector. Fine from process context. But mnt_ns_tree_remove()
hands the reference the namespace was allocated with to call_rcu() and
so the marks are removed from the RCU softirq:
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:623
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/3
__mutex_lock+0x113/0x24b0
fsnotify_destroy_marks+0x11b/0x3d0
mnt_ns_release_rcu+0x57/0xa0
rcu_core+0x6b6/0x1e40
and lockdep complains about the connector lock being taken from softirq
context. A fanotify group with a FAN_MARK_MNTNS mark on the mount
namespace of another task is all that's needed. Root in a user
namespace can do that for a mount namespace it owns. The task exits and
the namespace is freed with the mark still on it.
Remove the marks in free_mnt_ns() before the namespace is handed to RCU.
That runs in process context once the last active reference is gone. A
mark is added through a file descriptor to the namespace which holds an
active reference so no mark can show up after that. |
| In the Linux kernel, the following vulnerability has been resolved:
statmount: read the parent of an unmounted mount under mount_lock
statmount_mnt_basic() reads the ids of the parent through m->mnt_parent
with namespace_sem held for reading. That's fine for a mount that is
in a namespace. Everything above it is pinned by that namespace.
STATMOUNT_BY_FD also accepts a file descriptor on a mount that has
been unmounted on purpose and that only the file descriptor keeps alive.
If that mount stayed attached to its parent when it was unmounted the
parent is unmounted as well and nothing pins it for the child.
The final mntput() unmounts the children under mount_lock alone and
frees the parent afterwards. Concurrently, statmount_mnt_basic() reads
m->mnt_parent twice while that can happen and can easily dereference a
mount that's already gone.
Read the parent of an unmounted mount under mount_lock. The parent
can't be put while it is held and both ids come from the same mount. A
mounted mount's parent is pinned by the namespace and a mount can't
leave its namespace while namespace_sem is held, so the common case
takes no global lock. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/panthor: validate userspace queue count against initialized firmware slot count
In panthor_drv.c:panthor_ioctl_group_create(),
the queue count is validated against the hardcoded maximum:
if (!args->queues.count || args->queues.count > MAX_CS_PER_CSG)
return -EINVAL;
However, if the firmware reports fewer slots than MAX_CS_PER_CSG,
panthor_fw_init_ifaces() will only initialize that smaller number of
stream interfaces.
If unprivileged userspace requests more queues than the firmware reported
(but no more than MAX_CS_PER_CSG), cs_slot_prog_locked() fetches an
uninitialized stream interface and may crash when dereferencing
cs_iface->input->ringbuf_base. |
| In the Linux kernel, the following vulnerability has been resolved:
namespace: reset the old parent's ->overmount in mnt_change_mountpoint()
__umount_mnt() resets ->overmount of the parent when it unmounts the
mount that overmounts it. mnt_change_mountpoint() doesn't. It moves the
mount to its new parent and leaves the old one pointing at it.
For a mount that is moved beneath in attach_recursive_mnt() that doesn't
matter. The new mount has already reset ->overmount of the old parent by
the time the old top mount is moved onto it.
It matters for reparent() though. propagate_umount() moves a surviving
overmount onto the first ancestor that isn't going to be unmounted. The
mount it was taken from is unmounted immediately afterwards. If a file
descriptor keeps that unmounted mount alive ->overmount points at the
moved mount. That's a dangling pointer and UAF as the moved mount is
unmounted and freed.
do_lock_mount() follows ->overmount from the target path under
mount_lock. With a file descriptor on such a mount as the target of a
mount beneath topmost_overmount() walks into the freed mount and
do_lock_mount() takes references on whatever it finds there.
So reset ->overmount of the old parent in mnt_change_mountpoint() the
same way __umount_mnt() does. A mount's ->overmount is then always a
mount that is attached to it. |
| In the Linux kernel, the following vulnerability has been resolved:
fs: don't silently unmount busy mounts
The propagate_mount_busy() helper exists to decide whether a synchronous
can suceed. It does that by looking at the copies of the victims in the
mounts its parent propagates to. One of those functions from propagation
hell.
It skips a copy that has child mounts except for the case of a single
child mount covering the copy's root. That algorithm used to be exact.
It isn't anymore.
Originally only childless copies were unmounted during propagation.
And 1064f874abc0 ("mnt: Tuck mounts under others instead of creating
shadow/side mounts.") ended up adding covered mounts to both sides in
one go.
Along came 99b19d16471e ("mnt: In propgate_umount handle visiting mounts
in any order") and that started to unmount more than before:
[1]: A copy of a mount is unmounted when each of its children is either
its overmount or a copy of the victim itself. In the former case
the overmount gets reparented. In the latter case the copy of the
victim will end up being unmounted.
So propagate_umount() ended up being rewritten without adjusting
propagate_mount_busy(). And currently propagate_mount_busy() doesn't
look at copies of the victim that have two or more children nor a single
child that is not the overmount.
So any such copy in [1] is not checked for
references. The result is that a synchronous unmount succeeds, pulling
out a mount that is still in use.
A container can run into this with its own mounts. The host shares a
tree with the container and the host has a mount in that tree:
mount -t tmpfs none /mnt
mount --make-shared /mnt
mount -t tmpfs none /mnt/a
The container's /mnt is a slave copy of the host mount. The container
now takes a detached copy of the tree and mounts that copy beneath its
propagated copy of /mnt/a and keeps the file descriptor to the tree
open:
unshare -m --propagation unchanged
mount --make-rslave /
fd = open_tree(AT_FDCWD, "/mnt", OPEN_TREE_CLONE | AT_RECURSIVE)
move_mount(fd, "", AT_FDCWD, "/mnt/a", MOVE_MOUNT_BENEATH)
grep /mnt /proc/self/mountinfo
775 355 ... /mnt ... master:646
777 775 ... /mnt/a ... master:646
776 777 ... /mnt/a ... master:647
778 777 ... /mnt/a/a ... master:647
The now attached tree (777) is now mounted beneath the container's copy
of /mnt/a. That's also where the host mount sits (as seen from the host
mount namespace). So the propagated copy (776) of the host's mount is on
top of its root and the copy of that (778) is inside it. Now the host
runs:
umount /mnt/a
and it succeeds. The moved tree tree and the copy inside of it are gone
from the container. Now only the propagated copy is left and it got
reparented to where it was before:
grep /mnt /proc/self/mountinfo
775 355 ... /mnt ... master:646
776 775 ... /mnt/a ...
But the file descriptor still refers to the moved tree. So a synchronous
umount detached a mount that is still in use.
Teach propagate_mount_busy() the same checks that propagate_umount()
does. It now checks for a single victim mount without children
for which it can assume that MNT_LOCKED is cleared on every copy like
propagate_umount() does. The copies form chains. IOW, when a copy itself
receives propagation from the victim's parent then the mount at the same
mountpoint inside that copy is a copy as well. Whether a mount receives
propagation from the victim's can simply be checked by walking its
masters. Walk each chain once from its top so we are sure that nested
copies stay linear. Check every reference once of every copy that gets
unmounted. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu/userq: only accept doorbell BOs as queue doorbell
amdgpu_userq_get_doorbell_index() pins any BO passed as doorbell_handle
into the doorbell domain. For a regular BO, TTM moves it with
ttm_bo_move_null() and its contents are lost. Since an importer on the
same device gets the exporter's GEM object, a client can do this to a
buffer another client shared with it.
Reject BOs that were not created in the doorbell domain.
v2: drop the error message, use a local abo variable (Christian)
(cherry picked from commit f7497bbc19db4821c62b9d97b31c9086feb2d917) |
| In the Linux kernel, the following vulnerability has been resolved:
drm/bridge: th1520-dw-hdmi: Fix remove() callback
This driver stores struct th1520_hdmi * in platform drvdata, but
th1520_dw_hdmi_remove() was reading it back as struct dw_hdmi *
and passing it to dw_hdmi_remove(), so teardown runs on the wrong
pointer.
Retrieve struct th1520_hdmi * from platform drvdata and pass
hdmi->dw_hdmi to dw_hdmi_remove(). |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: scsi_transport_fc: Widen FPIN pname walker counter to u32
An adjacent Fibre Channel fabric actor that can deliver an FPIN ELS
frame to an lpfc or qla2xxx Linux initiator can trigger a non-return in
the generic FC transport. This is not a local userspace or IP network
path; the attacker must be able to inject fabric traffic, for example as
a compromised switch or fabric controller, or as a same-zone N_Port on a
fabric that permits source spoofing.
The Link-Integrity and Peer-Congestion FPIN walkers used a u8 loop
counter against the 32-bit on-wire pname_count field, and did not bound
pname_count by the descriptor body already validated by the TLV walker.
A pname_count of 256 therefore wraps the counter and keeps the loop
condition true indefinitely.
Factor the shared pname_list[] walk into one helper, widen the counter
to u32, and clamp pname_count against the entries that fit in the
descriptor body before iterating. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/xe: Fix stale pinned_link entry when fb-pin performs the final unpin
xe_bo_pin_external() and xe_bo_unpin_external() maintain the bo's
pinned_link list membership in xe->pinned.late.external, based on
whether the current call is the outermost pin or the final unpin.
However, the same external bo's pin_count can also be raised and
lowered directly by __xe_pin_fb_vma()/__xe_unpin_fb_vma(), which pin
the bo as a display scanout buffer without going through
xe_bo_pin_external()/xe_bo_unpin_external() at all, and have no
notion of, or ownership over, pinned_link.
If a bo is pinned both externally (e.g. dma-buf export) and as an fb,
and the external unpin happens first, xe_bo_unpin_external() correctly
observes pin_count > 1 and leaves the bo on pinned_link. When the fb
unpin later performs the true last unpin (pin_count 1 -> 0), it never
touches pinned_link, leaving the bo linked on xe->pinned.late.external
indefinitely. Once the bo is subsequently freed, this stale list entry
points into freed memory, corrupting the list and risking a
use-after-free the next time the list is walked or spliced.
The backup object pin/unpin sites in xe_bo_notifier_prepare_pinned()/
xe_bo_notifier_unprepare_pinned() have the same bypass characteristic,
though they never add their bo to a pinned list, so are not affected
by this particular list-corruption issue.
Move the pinned_link removal into xe_bo_account_unpin(), which already
runs on every unpin path (kernel, external, framebuffer, backup
object) right before the true 1 -> 0 pin_count transition. Since
list_del_init() only operates on the node itself, this removal is
list-agnostic and safe to perform regardless of which list (external
or kernel_bo_present) the bo happens to be linked on, or which code
path is performing the final unpin. Drop the now-redundant explicit
list_del_init() calls in xe_bo_unpin_external() and xe_bo_unpin().
v2:
- New patch
v3:
- Rebased on changes to previous patch.
(cherry picked from commit ca58d36a1f93af586ee93b340c9f9fd81312cc01) |
