| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
watchdog: at91sam9_wdt: prevent timer rearm during teardown
at91_ping() rearms the watchdog timer from its callback. timer_delete()
neither waits for a running callback nor prevents it from rearming the
timer, so probe failure or driver removal can leave the timer accessing the
devm-allocated at91wdt after it has been freed.
Use timer_shutdown_sync() on both teardown paths. It waits for a running
callback and rejects any attempt by the callback to rearm the timer. |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: clear control chunk transport if it is being removed
sctp_make_heartbeat_ack() caches the destination transport in
chunk->transport without taking a reference. When src_out_of_asoc_ok is
enabled, the HEARTBEAT ACK may remain queued on control_chunk_list instead
of being transmitted immediately.
If the peer transport is removed while the chunk is still queued,
sctp_assoc_rm_peer() drops the transport and schedules it for RCU freeing,
but only clears cached transport pointers in out_chunk_list. The queued
control chunk therefore retains a dangling transport pointer.
Once an ASCONF_ACK clears the suppression and the queued control chunk is
transmitted, SCTP dereferences the stale transport pointer, leading to a
use-after-free.
Fix this by also clearing chunk->transport for queued control chunks in
control_chunk_list when removing the transport. |
| In the Linux kernel, the following vulnerability has been resolved:
net/openvswitch: check Ethernet header length in key_extract()
When a packet arrives on an ARPHRD_NONE device (e.g. TUN),
ovs_flow_key_extract() trusts the user-provided skb->protocol field: if
it is ETH_P_TEB, the packet is classified as MAC_PROTO_ETHERNET and
key_extract() is called without ensuring the skb has ETH_HLEN (14) bytes
of linear data. key_extract() unconditionally pulls 2 * ETH_ALEN bytes
for MAC addresses and parse_ethertype() pulls 2 more, either of which
triggers a kernel BUG in __skb_pull() when the linear area is too small.
kernel BUG at include/linux/skbuff.h:2848!
RIP: 0010:key_extract+0xa7e/0xd90 net/openvswitch/flow.c:933
ovs_flow_key_extract+0x419/0xa70
ovs_vport_receive+0x222/0x390
netdev_frame_hook+0x3e0/0x630
tun_get_user+0x2d0c/0x38e0
Fixed by calling check_header() in key_extract() before accessing the
Ethernet header. |
| In the Linux kernel, the following vulnerability has been resolved:
udp: fix potential use-after-free in tunnel segmentation
__skb_udp_tunnel_segment() gets the UDP header before ensuring the
tunnel header is in the skb head. If the pull reallocates skb->head,
the saved UDP header pointer is no longer valid.
Get the UDP header after the pull to avoid a potential use-after-free. |
| In the Linux kernel, the following vulnerability has been resolved:
vdpa/mlx5: Fix buffer length in create_direct_keys()
We have seen in our CI the following KASAN message:
BUG: KASAN: slab-out-of-bounds in cmd_exec+0x550/0xca0 [mlx5_core]
Read of size 272 at addr 0000000176795020 by task qemu-system-s39/82764
[...]
[<000011388ab3a7a0>] cmd_exec+0x550/0xca0 [mlx5_core]
[<000011388ab3b61c>] mlx5_cmd_exec_cb+0x25c/0x4f0 [mlx5_core]
[<000011388b21e82e>] mlx5_vdpa_exec_async_cmds+0x22e/0x5e0 [mlx5_vdpa]
[<000011388b21fd44>] create_direct_keys+0x954/0xef0 [mlx5_vdpa]
[...]
The buggy address is located 4128 bytes inside of
allocated 4384-byte region [0000000176794000, 0000000176795120)
So in essence we read 16 bytes beyond 4384-byte allocation.
create_direct_keys calculates the pointer and length for in and out
buffers.
The size calculation for in includes the entire structure
size (out + in + mtt[]) but the pointer passed to cmd_exec points only
to the 'in' field, skipping the 'out' field.
This causes mlx5_copy_to_msg() to read beyond the allocated buffer
by sizeof(out) bytes when copying command data.
Properly calculate the input size to match the pointer and allocation size. |
| In the Linux kernel, the following vulnerability has been resolved:
accel/amxdna: Fix page-insertion errors in amdxdna_insert_pages()
Two error paths in amdxdna_insert_pages() called vma->vm_ops->close(vma)
before returning an error code to the caller. This is incorrect:
amdxdna_gem_obj_mmap() registers an HMM interval notifier before calling
amdxdna_insert_pages(), and on a hard error it jumps to hmm_unreg to undo
that registration. Calling vm_ops->close() manually — which drops the
shmem pages_pin_count and the GEM object reference that backs the VMA —
before the mmap syscall has even returned causes those resources to be
released while the VMA is still alive. The kernel VMA teardown will call
vm_ops->close() a second time when the process later unmaps the range,
producing a reference count underflow.
Replace both hard-error returns with a deferred-fault approach that keeps
the VMA alive and retries page insertion through the HMM range-fault path. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: lzo: reject inline extents without valid headers
[BUG]
For a crafted btrfs image, the following KASAN can be triggered when
reading an inline lzo compressed file extent:
BUG: KASAN: slab-out-of-bounds in lzo_decompress+0x57d/0x700
Read of size 4 at addr ffff888006f2e644 by task btrfs_lzo_inlin/77
Call Trace:
<TASK>
dump_stack_lvl+0x5b/0x70
print_report+0xd1/0x610
kasan_report+0xe0/0x110
__asan_report_load_n_noabort+0x13/0x20
lzo_decompress+0x57d/0x700
btrfs_decompress+0x140/0x1c0
uncompress_inline+0x147/0x1b0
btrfs_get_extent+0xb23/0x10a0
btrfs_do_readpage.constprop.0+0x538/0x1ac0
btrfs_readahead+0x32f/0x5f0
read_pages+0x16f/0x850
page_cache_ra_unbounded+0x296/0x490
do_page_cache_ra+0xd9/0x130
page_cache_sync_ra+0x3ee/0x6f0
filemap_get_pages+0x306/0x15c0
filemap_read+0x329/0xd00
btrfs_file_read_iter+0x1f8/0x2b0
vfs_read+0x4ef/0x720
ksys_read+0xf8/0x1d0
__x64_sys_read+0x71/0xb0
x64_sys_call+0x1ab0/0x1b70
do_syscall_64+0x61/0x470
entry_SYSCALL_64_after_hwframe+0x4b/0x53
</TASK>
[CAUSE]
For an inline lzo compressed file extent, there should always be one lzo
header, recording the total length of the compressed data, followed by
one segment header, recording the compressed lzo payload.
But if a crafted inline lzo compressed file extent contains only an lzo
header, without the segment header or payload, lzo_decompress() will
still try to read the segment header, causing a read beyond the item
boundary.
Furthermore if the inline lzo compressed file extent is the first item
of the leaf, it will be at the extent buffer boundary. The above
out-of-boundary read will go beyond the extent buffer boundary,
triggering the above KASAN report.
[FIX]
Validate the total length of the inlined lzo compressed file extent, to
make sure there is at least one LZO header and one segment header, and a
non-zero payload.
[ Rework the commit message to remove slop ] |
| In the Linux kernel, the following vulnerability has been resolved:
xfs: handle NULL b_addr in xfs_buf_free
When xfs_buf_alloc_backing_mem() fails, xfs_buf_free() is called with
bp->b_addr still NULL. The code falls through to the folio_put path
which calls virt_to_folio(NULL), dereferencing an invalid address and
causing a kernel crash.
Call Trace:
xfs_buf_free+0x25f/0x510
xfs_buf_alloc+0xc98/0x19b0
xfs_buf_find_insert+0x55/0x14d0
xfs_buf_get_map+0x122b/0x17c0
xfbtree_init_leaf_block+0x11c/0x4a0
xfbtree_init+0x1bb/0x460
xrep_rmap_setup_scan+0x100/0x1f0
xrep_rmapbt+0x41/0xc0
Fix this by skipping folio_put() when bp->b_addr is NULL. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: us144mkii: re-anchor capture URBs on resubmission
capture_urb_complete() resubmits each capture URB without anchoring it:
usb_get_urb(urb);
ret = usb_submit_urb(urb, GFP_ATOMIC);
Anchoring is a property of a submission, not of the URB. The giveback
path calls usb_unanchor_urb() before urb->complete(), so an URB
resubmitted from its own completion handler is off the anchor. The
capture URBs are anchored once, at stream start, so from the first
completion onward tascam->capture_anchor is empty.
tascam_free_urbs(), tascam_disconnect(), tascam_suspend() and the
stop-work path all call usb_kill_anchored_urbs(&tascam->capture_anchor)
to reap the capture URBs before anything is freed. With the anchor empty
those calls return immediately and the URBs stay queued on the host
controller.
tascam_free_urbs() then returns the capture transfer buffers with
usb_free_coherent(), and snd_card_free() releases the snd_card
allocation that embeds tascam (card->private_data). The controller
completes the queued URBs afterwards, writing device-supplied data into
the freed transfer buffer, and capture_urb_complete() dereferences the
freed driver object.
KASAN on 7.2.0-rc5 (arm64):
BUG: KASAN: slab-use-after-free in dummy_timer
Write of size 512 at addr ffff000015b62000
__asan_memcpy
dummy_timer
hrtimer_run_softirq
Allocated by task 64:
usb_alloc_coherent
tascam_alloc_urbs
tascam_probe
Freed by task 170:
usb_free_coherent
tascam_free_urbs
tascam_disconnect
usb_unbind_interface
BUG: KASAN: slab-use-after-free in capture_urb_complete
Read of size 4 at addr ffff0000170ee878
Freed by task 170:
release_card_device
snd_card_free
tascam_disconnect
Restore the usb_anchor_urb() between the reference count bump and the
resubmission. That also makes the handler's usb_unanchor_urb() failure
arm meaningful again and restores usb_kill_anchored_urbs() as a barrier
on the disconnect, suspend and stop-work paths.
The anchoring was removed on the premise that the URB is already anchored
from the initial submission, which does not hold once the first giveback
has run.
Discovered by XBOW, triaged by Baul Lee <baul.lee@xbow.com> |
| In the Linux kernel, the following vulnerability has been resolved:
vsock/virtio: read virtqueues under worker locks
Commit bd50c5dc182b ("vsock/virtio: add support for device
suspend/resume") made the *_run flags transition from false to true when
restore installs replacement virtqueues. The RX, TX and event workers
read their virtqueue before locking and checking the corresponding flag,
so a worker delayed across freeze and restore can observe the replacement
queue's running state while retaining a pointer to the deleted queue.
Read each virtqueue under its mutex after checking the run flag, keeping
the pointer and state in the same queue generation. |
| In the Linux kernel, the following vulnerability has been resolved:
net: atlantic: free RX pages of consumed but not refilled buffers
aq_ring_rx_deinit() only walks [sw_head, sw_tail), the region posted to
hardware. Since the page reuse strategy was added, a cleaned RX buffer
keeps its page (and its DMA mapping) in the ring for reuse, and refill
is batched: aq_ring_rx_fill() returns early until AQ_CFG_RX_REFILL_THRES
slots are free. Slots that were consumed but not yet reposted therefore
sit in the complementary [sw_tail, sw_head) gap with a live page, and
the deinit walk never visits them: up to a refill batch worth of pages
and DMA mappings leak on every interface down.
Walk the whole ring instead and release whatever is still there. Also
bail out if the buffer ring is already gone: a partial
aq_ptp_ring_alloc() failure frees the ring but leaves aq_nic set, so
aq_ptp_ring_deinit() still gets here on the unwind path. |
| In the Linux kernel, the following vulnerability has been resolved:
net: devmem: prevent net-iov / page mixing
We should either have net_iov or page backed frags in a single skb,
otherwise it blows up down the stack. Don't allow mixing in
zerocopy_fill_skb_from_devmem(). |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: prevent in6_dev_get() from resurrecting inet6_dev
in6_dev_get() reads dev->ip6_ptr under RCU and then unconditionally
increments its refcount. Device teardown can clear the pointer and drop
the last reference between these operations. The increment then
resurrects an object whose RCU free has already been queued, so callers
can use it after it is freed.
Use refcount_inc_not_zero() and return NULL when the object has already
reached zero. RCU keeps the memory accessible through the attempted
reference acquisition, and a successful increment pins the object for
the caller.
An independent run on the exact unpatched 6f5156d7a31a (v7.2-rc3)
kernel reproduced the invalid reference acquisition as UID 1000:
refcount_t: addition on 0; use-after-free.
ip6_mc_source+0xef4/0x17e0
It was followed by the corresponding reference underflow in
ip6_mc_source(). The supplied trace from the same unpatched revision
additionally shows the access after the RCU read-side section ends:
BUG: KASAN: slab-use-after-free in mutex_lock+0x76/0xe0
Write of size 8 at addr ffff888015b50240 by task poc/1219
Bug found and triaged by OpenAI Security Research and
validated by Trail of Bits. |
| In the Linux kernel, the following vulnerability has been resolved:
tracing: Fix NULL pointer dereference in module event cache removal
A module-only event filter such as ":mod:foo" is cached with a NULL
event_mod->match when foo has not been loaded. If a later write tries to
remove a specific match from the same module, remove_cache_mod() passes
the NULL cached match to strcmp(), causing a NULL pointer dereference.
The issue can be reproduced from userspace:
echo ':mod:trace_events_kunit_missing' > /sys/kernel/tracing/set_event
echo '!foo_bar:mod:trace_events_kunit_missing' >> /sys/kernel/tracing/set_event
The second write must be a concatenation (">>") to not include O_TRUNC as
that would cause ftrace_clear_events() to clear the cached modules lines.
The crash was reproduced on x86_64 QEMU while KUnit workers contended on
the event tracing path:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
RIP: 0010:strcmp+0x10/0x30
Call Trace:
__ftrace_set_clr_event_nolock+0x373/0x4a0
ftrace_set_clr_event+0xf0/0x180
ftrace_event_write+0xdf/0x110
vfs_write+0xf6/0x440
ksys_write+0x68/0xe0
do_syscall_64+0xf9/0x540
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Check event_mod->match before comparing it, consistent with the existing
NULL checks for the cached system and event fields. The mismatched removal
continues to return -EINVAL; a broad cached module filter is removed with
"!:mod:<module>". |
| In the Linux kernel, the following vulnerability has been resolved:
futex: Prevent robust futex exit race some more
A robust futex unlock stores 0 over the whole futex value - wiping
FUTEX_WAITERS - and wakes a single waiter. That wakeup is a one-shot
notification: the protocol relies on its recipient to either acquire the
futex (and eventually unlock while aware of the remaining contention) or
re-arm FUTEX_WAITERS before sleeping again. If the woken waiter is killed
before it can do either, the kernel must jump in and wake the next task
down the line.
This is a known complication of the futex protocol with a previous
partial fix in commit ca16d5bee598 ("futex: Prevent robust futex exit
race"). Unfortunately, that fix is insufficient.
If a third task re-acquired the futex through the uncontended fast
path in the meantime, the notification is lost: robust exit processing
sees that it is owned by another task and does nothing, while the new
owner sees no FUTEX_WAITERS when it unlocks and wakes nobody.
The remaining waiters sleep forever behind a free futex:
A owns the futex, B and C sleep in FUTEX_WAIT
uval == A | FUTEX_WAITERS
A robust unlock: store 0, FUTEX_WAKE(1) wakes B
uval == 0
D fast path acquire: cmpxchg(0 -> D)
uval == D, no FUTEX_WAITERS
B killed before acting on the wakeup
B exit walk, pending op: owner D != B -> no action
D unlock: no FUTEX_WAITERS -> no wake
C sleeps forever
This is clearly a shortcoming in the implementation, which fails to keep
the FUTEX_WAITERS bit consistent.
Work around this by augmenting the robust list exit processing to also
perform the extra wakeup if the futex word is owned by another thread but
FUTEX_WAITERS is not set.
This does not fix the problem of a non-contended take over/release and free
sequence, which has been discussed for years and has been addressed by
commit 3ca9595d9fb6 ("futex: Add support for unlocking robust futexes") and
subsequent changes, but failed to take the problem described above into
account.
A more complete solution which is based on the in kernel unlock of
contended robust futexes has been discussed in the context of this change
and should show up in mainline sooner than later.
[ tglx: Amend change log slightly and fixup coding style ] |
| In the Linux kernel, the following vulnerability has been resolved:
inet: frags: publish queues before arming timer
inet_frag_create() arms the fragment queue timer before inserting the
queue into the fqdir rhashtable. If the namespace fragment timeout is
zero or negative, the timer can run before the queue is published.
The timer callback then marks the queue complete, tries to remove a node
that is not in the hash table yet, and drops the anticipated hash
reference. Creation can subsequently publish the completed queue without
restoring that reference, leaving a stale hash node after the caller drops
the remaining reference.
Publish the queue first and arm the timer while holding the queue lock.
This makes timer expiry wait until the queue is visible in the hash table,
so inet_frag_kill() can remove the node and balance the hash reference. |
| In the Linux kernel, the following vulnerability has been resolved:
gpio: pca953x: fix pca953x_irq_bus_sync_unlock regmap lock
Locking is disabled in the regmap config as this driver uses its own
lock. This means that all calls to regmap functions (read or write) must
hold the i2c_lock. The function pca953x_irq_bus_sync_unlock() did not do
this, and it was therefore possible that multiple threads could cause an
incorrect register to be read/written.
A previous patch partly fixed this, but only protected the write to the
interrupt mask register, and not the read from the direction register. |
| In the Linux kernel, the following vulnerability has been resolved:
net: openvswitch: reallocate update replies for mismatched IDs
ovs_flow_cmd_new() preallocates the optional reply skb before it takes
ovs_mutex and before it knows which existing flow will be updated.
That is normally fine because the skb is sized from the request flow
identifier. That identifier also becomes the inserted flow's identifier.
For updates, however, a request with a UFID may miss the UFID lookup and
then fall back to the flow key lookup. That lookup can legitimately find
an existing key-identified flow. UFIDs are optional and the flow key is
the primary identifier.
For echoed replies, ovs_flow_cmd_fill_info() writes the matched flow's
identifier, not the request identifier used for the preallocation. A short
request UFID can therefore leave too little room for the key identifier.
The fill can then fail with -EMSGSIZE and hit the BUG_ON(error < 0) in the
update path.
Once the update target has been resolved, reallocate the reply skb if the
matched flow needs a larger reply than the request identifier allowed. Do
this before replacing the actions so the request can still fail cleanly if
the rare extra allocation fails. |
| In the Linux kernel, the following vulnerability has been resolved:
ima: fix out-of-bounds read in xattr_verify()
The digest-length check in xattr_verify() mixes int and size_t:
if (xattr_len - sizeof(xattr_value->type) - hash_start >=
iint->ima_hash->length)
sizeof() yields size_t, so the usual arithmetic conversions promote
the whole left-hand side to unsigned 64-bit before the subtraction
runs. For a truncated xattr this underflows instead of going negative:
a 1-byte IMA_XATTR_DIGEST_NG xattr (xattr_len == 1, hash_start == 1)
turns "1 - 1 - 1" into SIZE_MAX, which is trivially >= ima_hash->length.
The check then passes and the following memcmp() reads
iint->ima_hash->length bytes starting past the end of the buffer
vfs_getxattr_alloc() allocated for it.
Nothing upstream clamps xattr_len back into a safe range first:
ima_get_hash_algo() only special-cases xattr_len < 2 to pick a default
algorithm, and evm_verifyxattr() returns INTEGRITY_UNKNOWN rather than
failing when no HMAC key is loaded, so a truncated security.ima value
reaches the length check as-is.
Rewrite the comparison so every operand stays a signed int and no
implicit conversion to size_t can occur. |
| In the Linux kernel, the following vulnerability has been resolved:
mm: fix incorrect flush address in direct page table reclaim
When zap_pte_range reclaims a page table, it does:
pte_free_tlb(tlb, pmd_pgtable(pmdval), addr);
and this is unconditionally wrong: if this code executes, addr *always*
points one past the end of the range covered by the table. The addr
parameter is used to flush the TLB (really the paging-structure-cache)
to drop references to the to-be-freed table, and any architecture that
cares about the parameter will flush the wrong address. (But they'll
still free the correct page).
I think it's worth contemplating why the kernel works at all.
If we hit the offending line of code, we will first clear the PMD entry
(line 1954, zap_empty_pte_table), then we will issue pending flushes if
force_flush is set (tlb_flush_mmu_tlbonly(tlb)), then we will skip the
retry on line 1979 (phew!), and then we will do the offending
pte_free_tlb call. *Or* we will clear the PMD entry immediately before
pte_free_tlb (line 1983, zap_pte_table_if_empty).
If we have any pending flushes (i.e. we actually zapped any last-level
entries) at the time we clear the PMD entry, then the flush really ought
to flush all references to the table (Linus certainly seems to think it
will on all architectures [0]).
The condition under which we have no accumulated flushes at the time of
the clear is very complex (the whole zap_pte_range function has absurdly
complex control flow). If we do hit the bad case, then we will end up
clearing the PMD entry after the last time the range is flushed, and any
CPU is free to cache a reference to the (empty) page table. If this
happens due to an ordinary read or write, it would segfault, so it would
be rare. But the cache could be speculatively filled as well. Then
we'll flush the wrong address and then free and possibly reuse the
table.
On x86, even flushing the wrong address works on non-KPTI Intel systems
because INVLPG flushes *all* paging-structure-caches, not just the ones
for the target address. But INVPCID does not, and flush_tlb_one_user
will use INVPCID if it's available. And then we're toast. AMD systems
are more susceptible: we set the EFER.TCE bit, which makes even INVLPG
only flush the target address.
I think this might fix an issue in ripgrep reported here:
https://github.com/BurntSushi/ripgrep/issues/3494
[0] https://lore.kernel.org/all/CA+55aFzBggoXtNXQeng5d_mRoDnaMBE5Y+URs+PHR67nUpMtaw@mail.gmail.com/T/#u |
