| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| This CVE ID has been rejected or withdrawn by its CVE Numbering Authority. |
| In the Linux kernel, the following vulnerability has been resolved:
vfio/pci: clear vdev->msi_perm after freeing it on init failure
vfio_msi_cap_len() lazily allocates the per-device MSI permission table:
vdev->msi_perm = kmalloc_obj(struct perm_bits, GFP_KERNEL_ACCOUNT);
if (!vdev->msi_perm)
return -ENOMEM;
ret = init_pci_cap_msi_perm(vdev->msi_perm, len, flags);
if (ret) {
kfree(vdev->msi_perm);
return ret; /* vdev->msi_perm left dangling */
}
When init_pci_cap_msi_perm() -> alloc_perm_bits() fails with -ENOMEM, the
error path frees vdev->msi_perm but leaves the freed pointer stored in
it. vdev->msi_perm is not re-zeroed later because struct
vfio_pci_core_device is per-device and persists across open/close cycles,
and the vfio_config_init() error path returns without calling
vfio_config_free(). So the dangling pointer outlives the failed open.
That leads to two use-after-frees on the same device:
1. Reuse. The next vfio_config_init() sees the stale pointer at
"if (vdev->msi_perm) return len;" and reuses the freed object. MSI
config accesses in vfio_pci_config_rw_single() then dereference and
call the freed perm->readfn / perm->writefn function pointers.
2. Double free. A later vfio_config_free() runs free_perm_bits() and
kfree() on the already-freed object.
Fix it by NULLing vdev->msi_perm after the kfree(), matching the
NULL-after-free discipline already used in free_perm_bits() and
vfio_config_free().
BUG: KASAN: slab-use-after-free in vfio_pci_config_rw_single (drivers/vfio/pci/vfio_pci_config.c:1961)
Read of size 8 at addr ffff88800fcc88d0 by task exploit/143
Call Trace:
...
kasan_report (mm/kasan/report.c:595)
vfio_pci_config_rw_single (drivers/vfio/pci/vfio_pci_config.c:1961)
vfio_pci_config_rw (drivers/vfio/pci/vfio_pci_config.c:1986)
vfio_pci_rw (drivers/vfio/pci/vfio_pci_core.c:1599)
vfs_read (fs/read_write.c:572)
__x64_sys_pread64 (fs/read_write.c:764)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
...
Followed on device close by a double free of the same object:
Oops: general protection fault, probably for non-canonical address
0x1f63e0e8000008: 0000 [#1] SMP KASAN NOPTI
RIP: 0010:kfree (mm/slub.c:6711)
Call Trace:
vfio_config_free (drivers/vfio/pci/vfio_pci_config.c:1861)
vfio_pci_core_disable (drivers/vfio/pci/vfio_pci_core.c:685)
vfio_pci_core_close_device (drivers/vfio/pci/vfio_pci_core.c:777)
vfio_df_close (drivers/vfio/vfio_main.c:602)
vfio_device_fops_release (drivers/vfio/vfio_main.c:648)
__fput (fs/file_table.c:512)
__x64_sys_close (fs/open.c:1496)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
...
Kernel panic - not syncing: Fatal exception |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: fix out-of-bounds read in ext4_read_inline_dir()
ext4_read_inline_dir() can read a dirent header past the end of its inline
buffer, triggering a slab-out-of-bounds read during getdents64():
BUG: KASAN: slab-out-of-bounds in __ext4_check_dir_entry
Read of size 2 at addr ffff88800f3dd23c by task exploit/148
...
__ext4_check_dir_entry
ext4_read_inline_dir
iterate_dir
The dirent payload lives in a buffer of exactly inline_size bytes:
dir_buf = kmalloc(inline_size, GFP_NOFS);
but iteration runs in a position space extra_offset bytes larger
(extra_size = extra_offset + inline_size) so the synthetic "." and ".."
land at their block-dir offsets. A dirent is formed at "dir_buf + pos -
extra_offset", yet the ext4_check_dir_entry() length argument uses the
larger extra_size. A position whose dirent header would extend past
extra_size is therefore accepted, and the rescan loop's rec_len probe and
ext4_check_dir_entry() dereference de->rec_len before the entry is rejected.
Reject a position whose minimum-size dirent header would not fit within
extra_size before forming de, in both the rescan and main loops, and pass
inline_size rather than extra_size to ext4_check_dir_entry() so the length
check matches the physical buffer. |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: check dir entry fits before reading the hash trailer in ext4_search_dir()
For casefolded encrypted directories ext4 stores an 8-byte hash trailer
after the name (EXT4_DIRENT_HASHES()), at an offset derived from
de->name_len. On the sb_no_casefold_compat_fallback() path ext4_match()
reads that trailer, but ext4_search_dir()'s by-hand pre-check only tests
de->name + de->name_len <= dlimit, which proves the name fits, not the
rounded trailer. A crafted entry whose name ends at the block boundary
passes the check while EXT4_DIRENT_HASHES(de) lands past the block end,
so ext4_match() reads out of bounds on an ordinary lookup. KASAN reports
it as a use-after-free when the page after the directory block holds a
freed object:
BUG: KASAN: use-after-free in ext4_match (fs/ext4/namei.c:1435)
Read of size 4 at addr ffff888010458000 by task exploit
Call Trace:
ext4_match (fs/ext4/namei.c:1435)
ext4_search_dir (fs/ext4/namei.c:1470)
__ext4_find_entry (fs/ext4/namei.c:1268 fs/ext4/namei.c:1632)
ext4_lookup (fs/ext4/namei.c:1703 fs/ext4/namei.c:1769)
...
filename_lookup (fs/namei.c:2842)
vfs_statx (fs/stat.c:353)
__do_sys_newfstatat (fs/stat.c:538)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
Require, for hash-in-dirent directories, that the whole entry including
the rounded trailer fits before calling ext4_match(). This is the same
bound ext4_check_dir_entry() already enforces via ext4_dir_rec_len(), so
no well-formed entry is rejected. The other caller, ext4_find_dest_de(),
runs ext4_check_dir_entry() first and is unaffected. |
| In the Linux kernel, the following vulnerability has been resolved:
perf: Fix use-after-free when perf mmap() revival races with the last munmap()
perf_mmap_close() drops rb->mmap_count *without* holding
event->mmap_mutex (the refcount_dec_and_test() right before the
refcount_dec_and_mutex_lock() of event->mmap_count). A concurrent
perf_mmap_rb() can slot its entire "revival" path into that window
(perf_mmap holds event->mmap_mutex for its whole duration, including
rb_alloc):
munmap side (perf_mmap_close) mmap side (perf_mmap_rb)
----------------------------------- --------------------------------
rb->mmap_count 1 -> 0 (no lock) (holds event->mmap_mutex)
inc_not_zero(rb->mmap_count) fails
ring_buffer_attach(event, NULL)
rb_alloc() + attach new rb
refcount_set(&event->mmap_count, 1)
lock; event->mmap_count 1 -> 0
ring_buffer_attach(event, NULL)
ring_buffer_put() -> frees the *new* rb
The revival's refcount_set(&event->mmap_count, 1) is an invisible
1 -> 1 write: the close frees the just-revived buffer although the
other process still has it mapped -- a page-level use-after-free
allowing local privilege escalation to root by any unprivileged user
(default kernel.perf_event_paranoid=2).
Swap the order of the two counter updates: event->mmap_count is
dropped first via refcount_dec_and_mutex_lock(), so its 1 -> 0
transition and the ring_buffer_attach() stay serialized with
perf_mmap(). rb->mmap_count == 0 then implies every event using the
buffer is detached already, so the result of the rb->mmap_count drop
can gate the remaining teardown directly and detach_rest is no longer
needed.
An earlier fix for this race from Kyle Zeng and David Lee takes
event->mmap_mutex around both counter updates [0]; here the not-last
close stays lockless. |
| In the Linux kernel, the following vulnerability has been resolved:
net: skbuff: don't skb_tx_error() the source skb in skb_zerocopy()
skb_zerocopy() copies frags from @from into @to. On an
skb_orphan_frags() failure it calls skb_tx_error(@from), a destructive
operation on the source skb the copy helper does not own. That completes
@from's zerocopy uarg and clears SKBFL_ALL_ZEROCOPY, including the
SKBFL_SHARED_FRAG page-ownership marker.
Both callers already report the failure on their own drop path.
nfnetlink_queue does it at nla_put_failure, and Open vSwitch does it in
the flow-miss drop arm of ovs_dp_process_packet(), so nothing is lost by
dropping it here.
On Open vSwitch's OVS_ACTION_ATTR_USERSPACE path the skb is not freed on
this error: do_execute_actions() ignores output_userspace()'s return
value and, unless the upcall was the last action, keeps forwarding the
same skb through the flow's remaining actions. The uarg is completed
while that skb is still in flight, telling the producer its buffers are
free, and SKBFL_SHARED_FRAG is cleared on an skb the rest of the stack
still handles. That flag is what makes esp_input() call skb_cow_data()
instead of decrypting in place, so a later local ESP delivery can
decrypt over frags the skb does not own privately.
Leave error reporting to the callers. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: fix slab-out-of-bounds write in ni_create_attr_list()
ni_create_attr_list() allocates a fixed buffer of al_aligned(record_size)
(== record_size) bytes and then walks every attribute of the primary MFT
record, writing one ATTR_LIST_ENTRY per attribute and advancing the cursor
by le_size(name_len), with no check against the end of the buffer; the
total size is only computed after the loop.
A minimum-size resident attribute occupies SIZEOF_RESIDENT (0x18 = 24)
bytes on disk, but an unnamed attribute expands to le_size(0) (0x20 = 32)
bytes in the list. Because the number of attributes in a record is not
bounded (mi_enum_attr() accepts arbitrarily many equal-type, nameless
minimum-size attributes), a crafted record packed with such attributes
produces a list larger than record_size and overflows the heap buffer.
This is reachable from a crafted, loop-mounted NTFS image: opening the file
and adding an attribute (e.g. via setxattr) drives ntfs_set_ea() ->
ni_insert_resident() -> ni_insert_attr() -> ni_ins_attr_ext() ->
ni_create_attr_list().
BUG: KASAN: slab-out-of-bounds in ni_create_attr_list+0xc48/0x1058
Write of size 4 at addr ffff000008984c00 by task setfattr/345
ni_create_attr_list+0xc48/0x1058
ni_ins_attr_ext+0x510/0x7c0
ni_insert_attr+0x3f8/0x70c
ni_insert_resident+0xc8/0x3b0
ntfs_set_ea+0x66c/0xd28
ntfs_setxattr+0x4d8/0x5b0
__arm64_sys_setxattr+0xa4/0x124
Allocated by task 345:
ni_create_attr_list+0x188/0x1058
The buggy address belongs to the cache kmalloc-1k of size 1024
(the write lands at object+1024).
Size the buffer from the actual attributes instead of assuming a single
record_size is always enough. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/xe: Don't hand out the flat CCS storage as usable VRAM
get_flat_ccs_offset() reads the base of the flat CCS storage from the
hardware, scales it by the number of enabled L3 nodes, and rounds the
result up to 128K. Everything below that offset is then handed to the
VRAM allocator as usable memory.
Rounding a limit that means "usable memory ends here" upwards publishes
whatever lies between the real base and the rounded one as free memory,
and that memory belongs to the compression hardware. The scaled value
has no reason to be 128K aligned, and on a Battlemage G21 with 16 GiB it
is not:
flat CCS base: raw 0x3fafff800, rounded 0x3fb000000
so the last 2 KiB of page 0x3fafff000 is CCS storage, in the allocator's
pool. Whatever is allocated there gets that tail overwritten by the
compression hardware, which needs no page-table entry, no buffer object
and no GPU submission to do it, and does it before userspace exists.
On this machine a Mesa VM's level-3 page table landed on that page on
every cold boot. It lost the entry covering the compositor's
batch-buffer heap, so the compositor's first submission faulted fetching
its batch and gdm restarted it forever: a black screen on an otherwise
working machine. Restarting gdm cleared it because the next VM's page
tables were allocated somewhere else.
Round down instead, to the page size the allocator works in. On this
machine that excludes exactly one page.
Reading the reserved page afterwards shows what had been writing it:
[369] 0xcccc000000000000
[371] 0xcc77000000000000
[373] 0xcccc000000000000
[375] 0xcc77000000000000
compression metadata, two bytes per sixteen, sitting where the driver
used to hand out memory.
The assertion that should have caught this compares the offset against
GSMBASE - ccs_size for equality. That value is 128K aligned, so it
agrees with the rounded-up offset precisely when the base is not
aligned - the check cannot fail in the case it exists to catch, and is
compiled out unless CONFIG_DRM_XE_DEBUG is set. Replace it with one
that can fail: CCS storage must not run into GSM.
[ And this was a debug session from hell, enormously helped by an AI
doing much of the grunt-work.
I'd like to call it my tireless helper, but the AI several times
stated flat out that this was impossible and unsolvable and that we
should just write a report about it.
I suspect those things have been trained by people who may not be
quite as stubborn as I am.
But while the AI was ready to give up several times, it did keep
adding debug code and analyzing it faithfully when I pushed. So credit
where credit is due and I let the AI write the commit message above.
This is basically a one-liner fixing a bogus "round_up()" to a
"round_down()", but there were 24 patches adding more and more debug
information to this, and 18 kernel boot to finally narrow it down to
this. - Linus ] |
| In the Linux kernel, the following vulnerability has been resolved:
mm/page_alloc: don't spin_trylock() in NMI on UP
Patch series "mm/page_alloc: fixes for free_pages_nolock() on RT/UP".
Pre-existing bugs found by Sashiko during review of this other series:
https://lore.kernel.org/all/20260703-alloc-trylock-v5-0-c87b714e19d3@google.com/
I have not reproduced these bugs, and I suspect there is no real-world
user that is affected by them.
This patch (of 2):
As noted in can_spin_trylock(), using this is unsafe in this context.
commit 620b46ed6ae17 ("mm/page_alloc: return NULL early from
alloc_frozen_pages_nolock() in NMI on UP") fixed this on the alloc side
but missed the free side.
Impact: If BPF programs using these features in NMI (probably tracing) are
present on non-SMP builds this might crash the kernel and is probably
exploitable by local attackers for privilege escalation. |
| In the Linux kernel, the following vulnerability has been resolved:
USB: gadget: ffs: fix mm lifetime handling
io_data stores a pointer to the submitting task's mm_struct,
but does not currently hold a reference to it while async
requests are pending.
This can result in a use-after-free if the task exits before
completion handling finishes.
Take a reference with mmgrab() when queuing the read request
and release it with mmdrop() on request completion. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_fs: Fix Use-After-Free in AIO error path
In ffs_epfile_write_iter() and ffs_epfile_read_iter(), when ffs_epfile_io()
fails with an error other than -EIOCBQUEUED, the io_data structure (`p`) is
freed. However, for AIO operations, the kiocb cancel function was already
armed and kiocb->private was set to `p`.
If a concurrent cancel operation (such as sys_io_cancel()) executes after
ffs_epfile_io() fails but before the function frees `p`, a Use-After-Free
can occur when the cancellation handler accesses the freed pointer.
To securely fix this race condition, we must properly un-arm the
cancellation. Invoking `kiocb->ki_complete()` does exactly this by
acquiring `ctx->ctx_lock` and safely removing the kiocb from the active
sequence. In doing so, it ensures that a parallel io_cancel can no longer
discover the kiocb, effectively closing the race window.
We then return -EIOCBQUEUED to notify the VFS layer that the kiocb has been
consumed and it should avoid attempting to complete the request again or
triggering subsequent completion handlers. |
| In the Linux kernel, the following vulnerability has been resolved:
zram: fix slot lock bit position on big-endian 64-bit
The slot lock is a bit operation on the whole __lock word, which flags and
ac_time alias as two u32s. On little-endian the lock bit lands in the
position ZRAM_ENTRY_LOCK reserves in flags, so the aliasing works out. On
64-bit big-endian it lands in ac_time instead: with
ZRAM_TRACK_ENTRY_ACTIME enabled, storing the access time from
mark_slot_accessed() or slot_free() wipes out the held lock bit, letting
another CPU take the same slot lock; an access time value with that bit
set makes the slot look locked forever.
Shift the lock bit into the flags half of the word on big-endian 64-bit. |
| In the Linux kernel, the following vulnerability has been resolved:
ceph: properly decrypt filenames in vmalloc() buffers
The fscrypt subsystem uses the scatterlist crypto API, inheriting its
requirement that any buffers are in the linear mapping region. However,
the messenger client uses kvmalloc() to create buffers for messages,
which will occasionally place those buffers in the vmalloc() region when
physical memory fragmentation doesn't permit a large enough kmalloc().
The various callers of ceph_fname_to_usr() directly pass (slices of) raw
messages from the MDS without considering that the messages may be in
vmalloc() buffers, resulting in oopses especially on non-x86 platforms
(see 'Closes:' for more details and a reproducer).
Make ceph_fname_to_usr() explicitly tolerant of vmalloc()-allocated
fname->ctext, fname->name, and/or oname->name buffers, using `tname`
(which, when non-null, must be a linear address; when null, is briefly
allocated as necessary) as a bounce buffer to avoid passing any
inappropriate addresses to fscrypt_fname_disk_to_usr().
Additionally change parse_reply_info_readdir() -- the only function to
supply its own `tname` -- to follow the new "tname must never come from
vmalloc()" rule by passing NULL when the message is not in the linear
region. Though this causes a per-dentry kmalloc()+kfree(), this overhead
exists only when processing the minority of messages that spill into
vmalloc(). My (crude) testing puts this at only about 1 in 8,000 readdir
messages. Still, if the overhead proves unreasonable in the future, it
is easy enough to mitigate: a future change could allocate a bounce
buffer in parse_reply_info_readdir() and use that as `tname` instead. |
| In the Linux kernel, the following vulnerability has been resolved:
HID: sony: clean up device list on probe failure
sony_input_configured() adds some controllers to sony_device_list before
HID core registers their input devices. input_register_device() can fail
after the callback returns successfully. sony_probe() then observes that
HID_CLAIMED_INPUT is clear and unwinds, but only stops the HID hardware.
The devres-managed sony_sc is freed while its list node remains linked, so
the next matching controller traverses freed memory.
Initialize the list node and device ID to inactive states. Make list
removal idempotent and run the driver-private cleanup on every probe
failure path. This also makes a second cleanup safe when
sony_input_configured() already unwound a partial initialization before
sony_probe() handles the missing input claim.
Found by 0sec (https://0sec.ai) using automated source analysis;
verified against the HID input registration and probe unwind paths. |
| In the Linux kernel, the following vulnerability has been resolved:
NFSD: Prevent client use-after-free during export state revocation
nfsd4_revoke_export_states() has the same use-after-free as
nfsd4_revoke_states(): it drops nn->client_lock across
revoke_one_stid() and the following read of clp->cl_minorversion, but
the stateid reference it holds does not pin the client. A teardown
racing the dropped lock can free the client while revoke_one_stid()
still dereferences it.
exportfs -u drives this path through NFSD_CMD_UNLOCK_EXPORT, so an
administrator removing an export can race a client expiry.
Skip a client that is already expiring and otherwise pin it with
cl_rpc_users under client_lock before dropping the lock, matching
nfsd4_revoke_states(). |
| In the Linux kernel, the following vulnerability has been resolved:
NFSD: Prevent client use-after-free during close_lru reaping
An nfs4_openowner left on nn->close_lru after its final CLOSE keeps
its last closed stateid in oo_last_closed_stid, holding only a raw
pointer to its nfs4_client. The laundromat reaps timed-out entries,
drops nn->client_lock, and calls nfs4_put_stid(), which dereferences
the client through cl_lock. Nothing pins the client across that
window, so a concurrent force_expire_client() can free it and
nfs4_put_stid() reads freed memory. __destroy_client() hits the same
race, walking clp->cl_openowners without cl_lock.
Pin the client with cl_rpc_users before dropping client_lock, and
skip clients already expiring. __destroy_client() then cleans up its
own close_lru entries through release_last_closed_stateid(), so
teardown no longer races the laundromat. |
| In the Linux kernel, the following vulnerability has been resolved:
NFSD: Prevent client use-after-free during blocked-lock reaping
A bare lock owner -- its only remaining reference a blocked lock on
nn->blocked_locks_lru -- holds a raw pointer to its nfs4_client but
no reference keeping the client alive. When the per-net laundromat
reaps such a lock, freeing the nbl drops the owner reference
held through flc_owner, and the final nfs4_put_stateowner()
takes the client's cl_lock. Because the laundromat detaches the
nbl first, __destroy_client() no longer finds it, so a concurrent
force_expire_client() can free the client before nfs4_put_stateowner()
runs, dereferencing cl_lock in freed memory.
Pin the client with cl_rpc_users before dropping
nn->blocked_locks_lock, and skip clients already expiring, whose
blocked locks __destroy_client() frees while holding an owner
reference. Take nn->client_lock outside nn->blocked_locks_lock.
Every other site holds nn->blocked_locks_lock as a leaf, acquiring
no further lock, so placing nn->client_lock outside it cannot form
a lock-order cycle. |
| In the Linux kernel, the following vulnerability has been resolved:
media: usbtv: keep device alive while ALSA card exists
The ALSA PCM callbacks store the driver state in pcm->private_data. An
open PCM file can outlive USB disconnect because usbtv_audio_free() uses
snd_card_free_when_closed(). The disconnect path can then drop the V4L2
device reference and free struct usbtv before ALSA releases the substream,
so a later close dereferences freed memory in snd_usbtv_pcm_close().
Take a V4L2 device reference for the ALSA card and drop it from the card
private_free callback. This keeps struct usbtv valid until ALSA has closed
the remaining files and freed the card. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: dwc3: clear forceRM when issuing EndTransfer
The forceRM bit of the DEPCMD register controls the behavior of the
EndTransfer command used to stop an active transfer. Older DWC3
programming guide revisions recommended setting forceRM=1 when
issuing EndTransfer. Newer programming guide revisions recommend
issuing EndTransfer with forceRM cleared.
With forceRM=1 on DWC_usb31 v2.00a and v2.10a controllers, a transfer
aborted through the ep_dequeue path was observed to remain active
after EndTransfer completion. A subsequent StartTransfer issued on the
same endpoint triggered writes associated with the aborted transfer.
This resulted in an SMMU fault because the transfer buffer had already
been unmapped during EndTransfer command-completion cleanup.
Using forceRM=0 eliminates the issue. Although older DWC3 programming
guide revisions recommended setting forceRM=1, no issues are known
from using forceRM=0. Clear forceRM when issuing EndTransfer to provide
consistent EndTransfer behavior and align with newer programming guide
recommendations. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: typec: qcom-pmic-typec: disable cc_debounce_dwork on stop
cc_debounce_dwork is queued from the set_cc() and start_toggling()
callbacks, which run from TCPM's kthread worker. port_stop() returns
before tcpm_unregister_port() destroys that worker. Flushing the worker
during unregister may therefore run a callback which queues the delayed
work after port_stop() has returned.
The delayed work can then run after devres has freed pmic_typec_port.
Use disable_delayed_work_sync() in port_stop() to cancel a pending
instance and prevent the TCPM callbacks from queueing another one.
This issue was found by an in-house static analysis tool. |
