| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
vt: skip screen update for DEC alignment test on backgroup consoles
[BUG]
Recently, we encountered a KASAN warning as follows:
BUG: KASAN: slab-out-of-bounds in fb_pad_aligned_buffer+0x11f/0x140
Read of size 1 at addr ff1100015fd9f6a4 by task tty_fbcon_oob/1239
CPU: 7 UID: 0 PID: 1239 Comm: tty_fbcon_oob Not tainted 7.3.0-rc1 #100 PREEMPT(full)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014
Call Trace:
<TASK>
...
kasan_report+0xf0/0x120
fb_pad_aligned_buffer+0x11f/0x140
ccw_putcs+0x86c/0xa80
fbcon_putcs+0x338/0x410
do_update_region+0x21d/0x450
do_con_write+0x1e0e/0x4880
con_write+0x13/0x80
n_tty_write+0x374/0x1010
file_tty_write.isra.0+0x404/0x7a0
...
reproduce:
1) open /dev/tty0, set a KDFONTOP ioctl with op.op = KD_FONT_OP_SET,
op.width = 8 and op.height = 16 (visible VC1)
2) open /dev/tty1, set a KDFONTOP ioctl with op.op = KD_FONT_OP_SET,
op.width = 28 and op.height = 24 (invisible VC2)
3) echo 3 > /sys/devices/virtual/graphics/fbcon/rotate_all
4) write EShash8(esc hash8) to tty1
[CAUSE]
All VCs render to the framebuffer. setfont only modifies the target VC's
font without resizing the framebuffer backing buffer (par->rotated.buf);
the buffer is only resized for the visible VC
(fbcon_do_set_font -> ... -> vc_do_resize -> update_screen). This relies on
the con_should_update() check performed before every update_region().
However, the ESC # 8 path (do_con_trol -> do_update_region) omits the
con_should_update() check. After changing the font size of an invisible VC,
do_update_region() fills using the new font size against a buffer that was
never resized, causing an out-of-bounds access.
[FIX]
Only push the update when the console is visible and not blanked, add
the con_should_update() check in the do_con_trol() like every other call
site of do_update_region() (update_region(), invert_screen(), ...). |
| In the Linux kernel, the following vulnerability has been resolved:
vc_screen: reload vc pointer before if (ret) in vcs_write() to avoid UAF
The reload of 'vc' added by commit 8fb9ea65c9d1 ("vc_screen: reload load
of struct vc_data pointer in vcs_write() to avoid UAF") sits after the
'if (ret)' block, so the copy-failure break path exits the loop without
reloading vc. If the vc was kfree()'d via vc_port_destruct during the
unlocked copy_from_user() window, the post-loop
'if (written && vc) vcs_scr_updated(vc)' is reached with a stale
non-NULL vc. The '&& vc' guard from commit a287620312dc ("vc_screen:
fix null-ptr-deref in vcs_notifier() during concurrent vcs_write") only
handles the NULL case, not this stale-non-NULL case; vcs_notifier() then
reads param->vc->vc_num from freed memory:
BUG: KASAN: slab-use-after-free in vcs_notifier+0x7c/0xd0
Read of size 2 at addr ffff888007149190
Call Trace:
vcs_notifier+0x7c/0xd0
atomic_notifier_call_chain+0x70/0xa0
vcs_scr_updated+0x77/0xa0
vcs_write+0x71b/0x7e0
Allocated by task: vc_allocate -> con_install -> tty_open
Freed by task: kfree <- vt_ioctl (VT_DISALLOCATE -> vc_port_destruct)
Move the reload to immediately after console_lock(), before 'if (ret)',
so every break path below passes a fresh vc to the post-loop
vcs_scr_updated(). |
| In the Linux kernel, the following vulnerability has been resolved:
virt: vmgenid: set driver_data before registering notification handlers
Both probe paths register their notification handler before assigning
driver_data, which the handler dereferences.
In the devicetree path, the notification IRQ can fire as soon as
devm_request_irq() registers the handler: the interrupt may already be
pending at probe time, for example when a VMM injects the
generation-changed notification while restoring a guest from a snapshot
that was taken before the driver had probed (Firecracker does exactly
this on snapshot restore). The IRQ is also requested with IRQF_SHARED,
so another device sharing the line can trigger the handler just as
early. The handler then calls vmgenid_notify(), which dereferences the
still-NULL driver_data and panics:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.18.38+ #1 PREEMPT(none)
Hardware name: linux,dummy-virt (DT)
pc : vmgenid_notify.isra.0+0x24/0x8c
lr : vmgenid_of_irq_handler+0x14/0x34
Call trace:
vmgenid_notify.isra.0+0x24/0x8c (P)
vmgenid_of_irq_handler+0x14/0x34
__handle_irq_event_percpu+0x44/0x1bc
handle_irq_event+0x4c/0xb4
handle_fasteoi_irq+0xf8/0x1f8
The ACPI path has the same ordering problem: the handler is installed
with acpi_install_notify_handler() before driver_data is assigned.
ACPI notifications are dispatched asynchronously from a workqueue, so
the window is narrow, but a notification arriving between the two calls
hits the same NULL dereference.
Assign driver_data before registering the handlers. The state is fully
initialized at that point, so the handlers are safe to run. Should
registration fail, the probe error path leaves no dangling pointer
behind: the driver core clears driver_data in device_unbind_cleanup(). |
| In the Linux kernel, the following vulnerability has been resolved:
netfs: clear post-EOF pagecache when extending a file via write
Fix netfs to erase the contents of a hole created after the EOF by an
ordinary write if dirty data has been previously left there by writes
through an mmapped region. Neither the buffered nor the unbuffered/DIO
write path clears that stale pagecache.
Zero the tail of the folio straddling the EOF before an extending
write. That is the only folio that can hold data written past the EOF
through an mmap, as pages wholly beyond the EOF can't be faulted in.
The folio is zeroed rather than dropped so a concurrent extending write
can't lose data.
Both write paths downgrade the i_rwsem to shared, so extending writes
can run concurrently and the i_size read by the caller may be stale by
the time the folio is locked. Re-read i_size under the folio lock and
clamp the zeroed range up to it, so a racing write that already put
data into the folio isn't clobbered.
Wait for any writeback on the folio to finish before zeroing it so that
the pagecache isn't modified while it may still be read by the transport
during transmission. Honour IOCB_NOWAIT by returning -EAGAIN rather
than blocking on the folio lock, on writeback, or in folio_mkclean()'s
rmap walk when the folio is mapped.
truncate_pagecache() can't be used here: it must be called with the
i_rwsem held exclusively, but these write paths only hold it shared,
and it would block unconditionally, breaking IOCB_NOWAIT.
Callers that hold i_rwsem exclusively for the whole resize (truncate,
setattr, fallocate, clone) exclude any genuine concurrent buffered
writer, so staleness can instead be decided from the folio's dirty
state, as pagecache_isize_extended() already does for filesystems that
serialise writes against truncate/setattr via a single i_rwsem.
Export netfs_clear_stale_post_isize() helper to handle such case.
The helper is required by the CIFS client to fix generic/363. |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: check RCV_SHUTDOWN after the sendmsg connect wait
sctp_wait_for_connect() drops the socket lock while it sleeps. An
out-of-the-blue ABORT can then be processed from the socket backlog and
unlink the association. If a concurrent shutdown(fd, SHUT_RD) sets
RCV_SHUTDOWN, the waiter breaks with err == 0 before checking
asoc->base.dead. Its final sctp_association_put() can then free the
association, leaving sctp_sendmsg_to_asoc() to continue with a dangling
pointer.
Check RCV_SHUTDOWN along with the wait error in sctp_sendmsg_to_asoc()
before using the association again. The check only accesses the socket,
so it needs no additional association reference. Return the existing
-ESRCH so that sctp_sendmsg() skips freeing a new association that may
already have been destroyed.
Keep sctp_wait_for_connect() unchanged to preserve its behavior for the
connect() caller. |
| In the Linux kernel, the following vulnerability has been resolved:
pfcp: fix socket lifetime on netdevice registration failure
pfcp_newlink() creates the UDP socket before register_netdevice().
If registration fails after pfcp_dev_init() succeeds, the core calls
pfcp_dev_uninit(), which releases the socket and clears pfcp->sk.
The newlink error path then releases it again, causing a NULL pointer
dereference. This was observed with failslab fault injection:
FAULT_INJECTION: forcing a failure.
kobject: kobject_add_internal failed for pfcp0 (error: -12 parent: net)
BUG: KASAN: null-ptr-deref in udp_tunnel_sock_release+0x1c/0x50
Read of size 8 at addr 0000000000000120 by task ip/1037
Call trace:
show_stack+0x18/0x24 (C)
dump_stack_lvl+0x78/0x90
print_report+0x468/0x5cc
kasan_report+0xa4/0xf0
__asan_load8+0x7c/0xd0
udp_tunnel_sock_release+0x1c/0x50
pfcp_newlink+0x128/0x184
rtnl_newlink+0x848/0xe44
rtnetlink_rcv_msg+0x468/0x514
netlink_rcv_skb+0xc0/0x1f0
rtnetlink_rcv+0x18/0x24
netlink_unicast+0x4b8/0x558
netlink_sendmsg+0x2b8/0x584
...
Return from pfcp_del_sock() if pfcp->sk is NULL. |
| In the Linux kernel, the following vulnerability has been resolved:
net/packet: prevent TX_RING byte count overflow
tpacket_snd() drains every SEND_REQUEST frame in a TX ring and adds
each valid packet length to the signed int len_sum. Userspace can
recycle completed frames concurrently, so a single blocking send call
is not bounded by the ring size.
After enough successful transmissions len_sum wraps into the negative
range. In particular, 65536 65535-byte frames followed by a 65007-byte
frame produce 0xfffffdef, or -EIOCBQUEUED. sock_sendmsg_nosec() treats
that as an impossible return and triggers a BUG. On systems configured
to panic on oops, a CAP_NET_RAW holder can panic the host kernel.
Stop before the next frame would make the byte count exceed INT_MAX.
The positive short count leaves that frame pending for a later send
call.
A two-thread TPACKET_V2 reproducer triggered the BUG on an arm64 build
of Linux 7.3-rc4. With this change, the same reproducer returned the
expected positive short count without an oops. |
| In the Linux kernel, the following vulnerability has been resolved:
net: extend IPv6 exthdr detection of tunneled packets
Commit c4336a07eb6b ("net: correctly handle tunneled traffic on IPV6_CSUM
GSO fallback") split skb_gso_has_extension_hdr() into mutually exclusive
branches on skb->encapsulation. This did not yet address all paths:
1. With skb->encapsulation set, the outer header is not checked. IPv6
tunnels such as ip6_gre and ip6_tunnel add an outer Destination
Options header by default (encap_limit). Their GSO packets skip
software GSO, then skb_csum_hwoffload_help() sees the outer extension
header and calls skb_checksum_help() on the GSO skb, which warns and
drops it.
2. Tunnels over IPv6 without an outer transport header, such as
ip6_tunnel, leave skb->transport_header at the inner transport
header. skb_network_header_len() then spans the outer IPv6, tunnel
and inner IP headers, a false positive.
3. UDP tunnels without an inner network header, such as SCTP-in-UDP or
PSP, have no inner IPv6 header to check. Decide on the outer header
alone.
4. Directly dereferencing inner_ip_hdr(skb)->version without
skb_header_pointer() is unsafe.
Instead, check ipv6_ext_hdr(nexthdr) on the outer IPv6 header and, if
set, on the inner IPv6 header. Read the headers with skb_header_pointer().
Keep the skb_network_header_len() check when !skb->encapsulation to also
catch encapsulated packets without skb->encapsulation (e.g., virtio).
Use the same helper in skb_csum_hwoffload_help(). Its open coded test
has the false positive of (2) and ignores the inner header.
Background: checksum offload of tunneled packets invariants:
Non-GSO skb:
- If the inner packet is CHECKSUM_PARTIAL, Local Checksum Offload computes
the outer checksum in software and the device offloads only the inner L4
checksum.
- If the inner packet is CHECKSUM_NONE (e.g., SCTP-in-UDP, ESP-in-UDP,
Remote Checksum Offload), the device offloads the outer UDP or GRE
checksum instead.
GSO skb:
- A device with NETIF_F_GSO_UDP_TUNNEL_CSUM or NETIF_F_GSO_GRE_CSUM
computes both inner and outer checksums per segment.
The outer checksum is seeded with only the pseudo-header checksum.
A NETIF_F_IPV6_CSUM device must parse through the outer headers to
reach the inner ones. |
| In the Linux kernel, the following vulnerability has been resolved:
net: gso: limit recursive IP-in-IP segmentation
IP-in-IP GSO can re-enter inet_gso_segment() or ipv6_gso_segment()
for each nested IP header. encap_level tracks header bytes, not callback
depth, so a deep chain can exhaust the kernel stack. Making
inet_gso_segment() stackable introduced unbounded IPv4 nesting; IPIP
GSO/TSO later made the path reachable. The IPv6 stackable path was
introduced separately and uses the same guard.
Count IPv4 and IPv6 GSO handler entries in skb_gso_cb, initialized once
per top-level GSO operation and preserved across GRE/UDP context changes.
Use the existing IP_TUNNEL_RECURSION_LIMIT for both handlers. The first
five entries pass, and the sixth returns -EINVAL before dispatching
another GSO callback. |
| In the Linux kernel, the following vulnerability has been resolved:
of/overlay: only treat a positive changeset id as registered
of_overlay_fdt_apply() stores the idr_alloc() return value in
ovcs->id before checking it. On failure the stored id is negative,
free_overlay_changeset()'s "if (ovcs->id)" check passes, idr_remove()
is called with a negative id and list_del() runs on ovcs->ovcs_list,
which is not initialized until after the id allocation. An allocation
failure at that point dereferences NULL.
Make free_overlay_changeset() treat only a strict-positive id as
registered. The rest of the function already copes with a
partially-initialized ovcs, so the error path stays a plain
goto err_free_ovcs. |
| In the Linux kernel, the following vulnerability has been resolved:
kprobes: Skip disarmed probes when checking optkprobe overlap
On x86, an optkprobe at A replaces five bytes with a jump. If a disabled
probe B is at A+2, get_optimized_kprobe() stops at B when arming a new
probe C at A+4. It leaves A optimized:
A A+1 A+2 A+3 A+4
A's jump | e9 | d0 | d1 | d2 | d3 |
after C | e9 | d0 | d1 | d2 | cc |
The INT3 for C overwrites the last byte of A's jump displacement, so
execution can jump to the wrong address. B can have prepared optinsns
while disarmed, but has no jump to unoptimize.
Continue past disarmed and unprepared probes to find the active optimized
probe before arming a probe in its jump. |
| In the Linux kernel, the following vulnerability has been resolved:
HID: multitouch: stop the release timer from being rearmed on remove
mt_remove() quiesces the sticky-finger timer before stopping the
hardware:
timer_delete_sync(&td->release_timer);
sysfs_remove_group(&hdev->dev.kobj, &mt_attribute_group);
hid_hw_stop(hdev);
timer_delete_sync() waits for a running callback and dequeues the timer,
but it does not stop the timer from being armed again. The transport is
still delivering reports at that point, and the report path rearms it:
if (app->quirks & MT_QUIRK_STICKY_FINGERS) {
if (td->mt_io_flags & MT_IO_SLOTS_MASK)
mod_timer(&td->release_timer,
jiffies + msecs_to_jiffies(100));
A report that arrives after timer_delete_sync() has returned therefore
leaves the timer queued. td is allocated with devm_kzalloc() against
hdev->dev, so it is freed when the driver is unbound, after mt_remove()
returns. When the timer fires afterwards, mt_expired_timeout()
dereferences the freed td:
struct mt_device *td = timer_container_of(td, t, release_timer);
struct hid_device *hdev = td->hdev;
if (test_and_set_bit_lock(MT_IO_FLAGS_RUNNING, &td->mt_io_flags))
Simply moving the teardown after hid_hw_stop() does not fix this on its
own, because mt_expired_timeout() calls mt_release_contacts(), which
walks hdev->inputs; the timer still has to be quiesced before
hid_hw_stop() tears the input devices down.
Use timer_shutdown_sync() instead, which additionally makes any later
mod_timer() a no-op, so neither ordering constraint has to be traded off
against the other. This is the final-teardown pattern the function was
introduced for, and hid-wiimote already uses it for the same reason. |
| phpMyFAQ 4.2.0-alpha before 4.2.0-beta contains a privilege escalation vulnerability in GroupController::saveCategoryRestrictions() that lets delegated administrators assign categories outside their own scope. Category-restricted administrators can POST to /admin/api/group/category-restrictions with out-of-scope or empty categoryIds to grant groups unrestricted category access. |
| phpMyFAQ 3.2.1 before 4.1.9 and 4.2.0-alpha before 4.2.0-beta contains a stored cross-site scripting vulnerability that allows authenticated content authors to inject JavaScript by embedding iframes with data:text/html sources in FAQ or News content. Attackers can bypass the hostless media-host allowlist in FaqHelper::cleanUpContent(), which is rendered via Twig's raw filter, to run phishing interfaces or top-frame redirects for viewers. |
| phpMyFAQ from 4.2.0-alpha before 4.2.0-beta contains a stored cross-site scripting vulnerability in SvgSanitizer that allows FAQ editors to store executable SVG files. Attackers can split script tags around removed tokens like processing instructions so single-pass removal reassembles them, executing script in the application origin when victims open the file. |
| In the Linux kernel, the following vulnerability has been resolved:
fprobe: Use guard(rcu_sched_notrace) and check rcu_is_watching()
unregister_fprobe() and unregister_fprobe_async() (used by BPF
kprobe-multi) rely on standard RCU grace periods (synchronize_rcu()
and call_rcu()) to wait until in-flight fprobe handlers complete before
freeing the fprobe.
However, if an fprobe handler executes while RCU is not watching (such
as in the idle loop or nohz_full extended quiescent states), standard
RCU does not track preemption-disabled sections. Consequently,
synchronize_rcu() does not wait for those executions, which can lead
to a use-after-free if the fprobe is freed immediately after
unregistration. Ensure handlers exit early when !rcu_is_watching().
Furthermore, fprobe_fgraph_entry() and fprobe_ftrace_entry() previously
used guard(rcu)() and rcu_read_lock(), which invoke lockdep on every
hit under CONFIG_PROVE_LOCKING. This adds overhead and can cause lockdep
recursion if probed functions interact with lockdep.
Since rhltable_lookup() and rhl_for_each_entry_rcu() use
rcu_dereference_all_check() (which checks rcu_read_lock_any_held()),
holding preemption disabled via rcu_read_lock_sched_notrace() is fully
valid and sufficient so long as rcu_is_watching() is true.
Define and use guard(rcu_sched_notrace)() across fprobe_ftrace_entry(),
fprobe_fgraph_entry(), and fprobe_return(). This eliminates fast-path
rcu_read_lock() and lockdep overhead while guaranteeing safe grace
period synchronization. |
| In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Wait for SCX_OPSS_DISPATCHING before reenqueueing a task
ebf1ccff79c4 ("sched_ext: Fix ops.dequeue() semantics") moved the final
ops_state store in scx_dispatch_enqueue() after the DSQ unlock so that the
custody update and ops.dequeue() precede it. A task can thus be found on a
DSQ while still SCX_OPSS_DISPATCHING.
The dequeue and core-sched pick paths wait for the state to clear in
ops_dequeue() but the reenqueue paths don't. A reenqueue in that window runs
ops.enqueue() and sets SCX_OPSS_QUEUED before the dispatch has completed.
The dispatcher's final store then overwrites it with SCX_OPSS_NONE and
finish_dispatch() drops every later dispatch of the task.
Wait for SCX_OPSS_DISPATCHING to clear before dequeueing a task for
reenqueue, the same way ops_dequeue() does. |
| In the Linux kernel, the following vulnerability has been resolved:
sched/cache: Introduce task_struct->sched_cache_grp to fix UAF
Add a sched_cache_grp pointer to task_struct so that scheduler code
can access the cache group directly via the task, without going
through mm->sched_cache_grp. This decouples the scheduler's hot-path
accesses from the mm_struct.
Each task holds its own refcount on the sched_cache_group, separate
from the reference held by its mm_struct. The reference is acquired
in copy_mm() (fork) and exec_mmap() (exec), and released in exit_mm().
This fixes the use-after-free when account_mm_sched() reaches the group
through a task whose mm is being switched, as reported by Hyunwoo:
https://lore.kernel.org/lkml/apPb-Dr4nPYuHQOK@v4bel/
Convert all scheduler code in fair.c and exit.c to use
p->sched_cache_grp instead of p->mm->sched_cache_grp.
Keep the fork/exec/exit reference management out of the generic mm
paths: add sched_cache_fork(), sched_cache_fork_cleanup(),
sched_cache_exec_mmap() and sched_cache_exit_mm() in
kernel/sched/cache_sched.c (with empty stubs for !CONFIG_SCHED_CACHE),
so fs/exec.c, kernel/fork.c and kernel/exit.c each call one helper
instead of open-coding the refcounting under #ifdef. Also add
sched_cache_group_get() and task_cache_group_get(). |
| In the Linux kernel, the following vulnerability has been resolved:
dm-pcache: reject a kset that overruns its segment
cache_replay(), the writeback worker and the GC worker read a kset of
get_kset_onmedia_size() bytes and advance the position by it. A forged
key_num makes that size exceed the segment's remaining space, so the
advance walks past the segment and trips the cache_pos_advance() BUG_ON.
Reject a kset whose on-media size exceeds cache_seg_remain() before use. |
| Gitea resolved the principals of an SSH certificate by searching the content of all stored public keys instead of only principal keys. When Gitea trusts a user certificate authority (`SSH_TRUSTED_USER_CA_KEYS`) and accepts arbitrary principals (`SSH_AUTHORIZED_PRINCIPALS_ALLOW=anything`), a user could register another user's public key line as their own principal, or a holder of a certificate signed by that authority could list it, and then authenticate as the owner of that key through the HTTP signature API and the built-in SSH server. Instances that do not trust a user certificate authority are not affected. |
