| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| 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:
bnge: Fix NULL pointer dereference in aux device release
If allocation of auxr_dev fails during auxiliary device setup, the error
path calls auxiliary_device_uninit(), which eventually invokes
bnge_aux_dev_release().
The release callback unconditionally dereferences aux_priv->auxr_dev->pdev
to retrieve the parent bnge_dev. Since auxr_dev has not yet been allocated
on this failure path, the dereference results in a NULL pointer exception
Retrieve the parent bnge_dev from the auxiliary device's parent instead of
auxr_dev, and free auxr_dev only when it was successfully allocated. This
allows the release callback to correctly clean up partially initialized
auxiliary devices. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_ncm: Use unsigned int for ndp_index
The variable ndp_index is declared as a signed integer, but it stores
the return value of get_ncm(), which is unsigned.
A malicious host can supply a large offset that overflows the signed
ndp_index, making it negative. Because ndp_index is compared against
unsigned bounds, this negative value bypasses sanity checks and leads
to an out-of-bounds read when calculating the address of the NDP
block (ntb_ptr + ndp_index).
Fix this by changing ndp_index to unsigned int to ensure consistent
unsigned comparisons throughout the function. |
| In the Linux kernel, the following vulnerability has been resolved:
serial: 8250_dma: Clear stale RX state on shutdown
serial8250_release_dma() terminates RX DMA and releases the channel, but
leaves rx_running set. If the port is closed while an RX transfer is
active, the stale state remains while rxchan is NULL until the channel is
requested again on the next open.
The DesignWare BUSY workaround added by commit a7b9ce39fbe4
("serial: 8250_dw: Ensure BUSY is deasserted") calls
serial8250_rx_dma_flush() from the LCR write path during startup. This
happens before serial8250_request_dma() obtains a new RX channel. On
reopen, the stale rx_running state therefore makes the flush path pass a
NULL channel to dmaengine_pause(), causing a kernel Oops.
Clear rx_running after terminating RX DMA, matching the TX cleanup. Also
make the flush helper return if the DMA object or RX channel is not
available so startup and teardown paths cannot pass a NULL channel to the
DMAengine API. |
| In the Linux kernel, the following vulnerability has been resolved:
net: bridge: mrp: fix uninitialised bytes on the wire
br_mrp_alloc_test_skb() builds MRP test frames on an skb from
dev_alloc_skb(), which does not clear the linear data area. On the MRA
ring-role branch the sub-option TLV header is appended with
sub_tlv = skb_put(skb, sizeof(*sub_tlv));
sub_tlv->type = BR_MRP_SUB_TLV_HEADER_TEST_AUTO_MGR;
so sub_tlv->length is never written, and the two trailing alignment bytes
are appended with a bare skb_put() that does not clear them either. The
neighbouring oui and sub_opt regions are explicitly zeroed, so three
uninitialised bytes are left in every MRA MRP_Test frame that goes out.
Put the sub-option TLV header and the alignment padding in a single
skb_put_zero(), which clears both. The AUTO_MGR sub-TLV carries no
payload, so the zeroed length field is already the value it should have. |
| 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:
samples/damon/mtier: error out for zero quota goal target values
Patch series "mm/damon: avoid division by zero from damos_quota_score()".
DAMON_SAMPLE_MTIER and DAMON_LRU_SORT allow the user to trigger division
by zero in damos_quota_score(). Avoid it by adding parameters validation
checks.
This patch (of 2):
damos_quota_score() can trigger division by zero if the target_value is
zero. DAMON_SAMPLE_MTIER lets users set the target_value via
node0_mem_{used,free}_bp parameters. It doesn't guard zero value case,
though. As a result, users can trigger division by zero. Fix the issue
by returning an error when the user tries to start DAMON with zero
node0_mem_{used,free}_bp parameter values.
DAMON_SAMPLE_MTIER is just a sample module, but the consequence is quite
bad. Also the zero node0_mem_free_bp parameter might look like a
reasonable setup to some users. Hence, the issue might really happen in
the real world.
One reliable way to reproduce the issue is like below:
# cd /sys/module/damon_sample_mtier/parameters
# echo 4096 > node0_start_addr
# echo 8192 > node0_end_addr
# echo 8192 > node1_start_addr
# echo 81920 > node1_end_addr
# echo 0 > node0_mem_free_bp
# echo Y > enabled
# dmesg -w
[...]
[18792.235916] Oops: divide error: 0000 [#1] SMP NOPTI
[...]
[18792.242787] RIP: 0010:damos_quota_score+0x6f/0x480
[...]
This issue was discovered [1] by Sashiko. |
| In the Linux kernel, the following vulnerability has been resolved:
mm/damon/lru_sort: error out for >10000 active_mem_bp
damos_quota_score() can trigger division by zero if the target value is
zero. DAMON_LRU_SORT lets users set the target value for the hot memory
scheme via active_mem_bp parameter. It avoids setting it as the target
value if the parameter value is zero. However, it also sets the cold
memory scheme with a target value that is calculated as '10000 -
active_mem_bp + 2'. Hence, if a user sets active_mem_bp 10002, the cold
memory scheme's quota goal target value can be zero. As a result,
division by zero can be triggered. Fix by returning an error when the
user tries to start DAMON with >10000 active_mem_bp parameter value.
It makes no sense to set active_mem_bp with 10002. It also requires
module parameters write permission to reproduce the issue. That said, the
consequence is quite bad.
One reliable way to reproduce the issue is like below:
# cd /sys/module/damon_lru_sort/parameters
# echo 1000 > wmarks_high
# echo 995 > wmarks_mid
# echo 0 > wmarks_low
# echo 10002 > active_mem_bp
# echo Y > enabled
# dmesg -w
[...]
[ 597.421247] Oops: divide error: 0000 [#1] SMP NOPTI
[ 597.428848] RIP: 0010:damos_quota_score+0x6f/0x480
This issue was discovered [1] by Sashiko. |
| 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:
fs,fsverity: remove check for fsverity being enabled in setattr_prepare()
The check that fs-verity is available in the kernel is not necessary
here. Filesystems could have fsverity files even without fs-verity
enabled. In that case, truncate on fsverity file will succeed, what this
check is trying to prevent. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/rxe: Fix double free in rxe_srq_from_init
In rxe_srq_from_init(), the queue pointer 'q' is assigned to
'srq->rq.queue' before copying the SRQ number to user space.
If copy_to_user() fails, the function calls rxe_queue_cleanup()
to free the queue, but leaves the now-invalid pointer in
'srq->rq.queue'.
The caller of rxe_srq_from_init() (rxe_create_srq) eventually
calls rxe_srq_cleanup() upon receiving the error, which triggers
a second rxe_queue_cleanup() on the same memory, leading to a
double free.
The call trace looks like this:
kmem_cache_free+0x.../0x...
rxe_queue_cleanup+0x1a/0x30 [rdma_rxe]
rxe_srq_cleanup+0x42/0x60 [rdma_rxe]
rxe_elem_release+0x31/0x70 [rdma_rxe]
rxe_create_srq+0x12b/0x1a0 [rdma_rxe]
ib_create_srq_user+0x9a/0x150 [ib_core]
Fix this by moving 'srq->rq.queue = q' after copy_to_user. |
| In the Linux kernel, the following vulnerability has been resolved:
platform/x86: ISST: Restore SST-PP control to all domains
The SST-PP control offset is only restored to power domain 0 after
resume. During suspend, control values are read and stored for all
power domains.
Use pd_info->sst_base instead of power_domain_info->sst_base, which
only points to power domain 0 base address. |
| In the Linux kernel, the following vulnerability has been resolved:
platform/x86: dell-laptop: fix missing cleanups in init error path
dell_init() initializes several resources after dell_setup_rfkill(),
including the optional touchpad LED, keyboard backlight LED, battery
hook, debugfs directory and dell-laptop notifier.
If a later LED or backlight registration fails, the error path only
tears down the battery hook and rfkill resources. This leaves the
notifier, debugfs directory, keyboard backlight LED and optional
touchpad LED registered after dell_init() returns an error.
Add the missing cleanup calls before tearing down rfkill. |
| In the Linux kernel, the following vulnerability has been resolved:
dmaengine: tegra: Fix burst size calculation
Currently, the Tegra GPC DMA hardware requires the transfer length to
be a multiple of the max burst size configured for the channel. When a
client requests a transfer where the length is not evenly divisible by
the configured max burst size, the DMA hangs with partial burst at
the end.
Fix this by reducing the burst size to the largest power-of-2 value
that evenly divides the transfer length. For example, a 40-byte
transfer with a 16-byte max burst will now use an 8-byte burst
(40 / 8 = 5 complete bursts) instead of causing a hang.
This issue was observed with the PL011 UART driver where TX DMA
transfers of arbitrary lengths were stuck. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: reject non-inline dinodes with i_size and zero i_clusters
On a volume mounted without OCFS2_FEATURE_INCOMPAT_SPARSE_ALLOC, a
non-inline regular file with non-zero i_size and zero i_clusters is
structurally malformed: the extent map declares no allocated clusters yet
the size header claims content exists. Keep rejecting that shape, but
express it through a shared predicate so the same invariant is available
to normal inode reads and online filecheck.
The same zero-cluster shape is also malformed for non-inline directories.
ocfs2 directory growth allocates backing storage before advancing i_size,
and ocfs2_dir_foreach_blk_el() later walks until ctx->pos reaches
i_size_read(inode). A forged directory dinode with a huge i_size and no
clusters would repeatedly fail on holes while advancing through the
claimed size.
Sparse regular files remain exempt: on sparse-alloc volumes, truncate can
legitimately grow i_size without allocating clusters. System inodes and
inline-data dinodes also retain their separate storage rules.
Mirror the check in ocfs2_filecheck_validate_inode_block() as well.
filecheck reports through its own error namespace, so malformed
size/cluster state is logged as a filecheck invalid-inode result rather
than via ocfs2_error(), but it must not proceed into
ocfs2_populate_inode(). |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: fix UBSAN array-index-out-of-bounds in ocfs2_sum_rightmost_rec
[BUG]
On-disk corruption setting l_next_free_rec to 0 in an inode's embedded
extent list triggers a UBSAN panic on the next write to that file.
[CAUSE]
ocfs2_sum_rightmost_rec() computes
i = le16_to_cpu(el->l_next_free_rec) - 1
and accesses el->l_recs[i] without validating i. When l_next_free_rec
is 0, i becomes -1; when l_next_free_rec exceeds l_count, i falls
past the end of the array. Either case violates the
__counted_by_le(l_count) annotation on l_recs[] and triggers UBSAN.
[FIX]
Validate the inode's embedded extent list when the inode is read, in
ocfs2_validate_inode_block(): l_count must be non-zero and no larger
than the inode block can hold, and l_next_free_rec must not exceed
l_count. A corrupt list is rejected at read time, before the b-tree
code can index l_recs[] out of bounds. |
| In the Linux kernel, the following vulnerability has been resolved:
tcp: defer md5sig_info kfree past RCU grace period in tcp_connect
The md5+ao reconciliation in tcp_connect() (net/ipv4/tcp_output.c)
has two symmetric branches:
if (needs_md5) {
tcp_ao_destroy_sock(sk, false);
} else if (needs_ao) {
tcp_clear_md5_list(sk);
kfree(rcu_replace_pointer(tp->md5sig_info, NULL, ...));
}
Both branches free a per-socket auth-info object while the socket is
in TCP_SYN_SENT and is already on the inet ehash (inserted by
inet_hash_connect() in tcp_v4_connect()). Both branches are reachable
by softirq RX-path readers that load the corresponding info pointer
via implicit RCU before bh_lock_sock_nested() is taken.
The needs_md5 branch is fixed in the prior patch by re-introducing
the call_rcu() free in tcp_ao_destroy_sock(): the equivalent per-key
loop runs inside tcp_ao_info_free_rcu(), the RCU callback, so by the
time it frees each tcp_ao_key all softirq readers that captured the
container have already completed rcu_read_unlock().
The needs_ao branch is not symmetric in the same way. The container
free can be deferred via kfree_rcu(md5sig, rcu) -- struct
tcp_md5sig_info already has the required rcu member
(include/net/tcp.h:1999-2002), and the rest of the tree already does
this in the tcp_md5sig_info_add() rollback paths
(net/ipv4/tcp_ipv4.c:1410, 1436). But the per-key teardown is done
by tcp_clear_md5_list() in process context BEFORE the container's
RCU grace period: it walks &md5sig->head and frees each
tcp_md5sig_key with bare hlist_del + kfree. A concurrent softirq
reader in __tcp_md5_do_lookup() / __tcp_md5_do_lookup_exact()
(tcp_ipv4.c:1253, 1298) walks the same list via
hlist_for_each_entry_rcu() and races with that bare kfree on the
keys themselves -- a per-key slab use-after-free of the same class
as the TCP-AO bug, on the same race window.
Fix this in two halves:
1. Convert the bare kfree() in tcp_connect() to kfree_rcu() so the
md5sig_info container joins the rest of the md5sig lifecycle.
The local-variable lift is mechanical and required because
kfree_rcu() is a macro that expects an lvalue.
2. Make tcp_clear_md5_list() RCU-safe by replacing hlist_del +
kfree(key) with hlist_del_rcu + kfree_rcu(key, rcu). struct
tcp_md5sig_key already carries the rcu member
(include/net/tcp.h:1995) and tcp_md5_do_del()
(net/ipv4/tcp_ipv4.c:1456) already uses kfree_rcu, so this
restores the lifecycle invariant the rest of the file follows
rather than introducing a one-off.
The other caller of tcp_clear_md5_list() is tcp_md5_destruct_sock()
(net/ipv4/tcp.c:412), which runs from the sock destructor when the
socket is already unhashed and unreachable; the extra grace period
there is unnecessary but harmless. Making the helper unconditionally
RCU-safe is the cleaner contract.
The needs_ao branch is not reachable by the userns reproducer used
to demonstrate the AO-side splat (the repro installs both keys but
ends up in the needs_md5 branch because the connect peer matches
the MD5 key, not the AO key); however the symmetric race exists
and a maintainer touching this code should not have to think about
which branch escapes RCU and which one does not.
[also credits to Qihang, who found that this races with tcp-diag] |
| In the Linux kernel, the following vulnerability has been resolved:
i2c: imx: fix locked bus on SMBus block-read of 0 (IRQ)
SMBus 3.1 6.5.7 allows a Block Read byte count of 0, but the
interrupt-driven block-read state machine rejects it as -EPROTO. Worse,
it returns without a NACK+STOP: the next receive cycle has already
started, so the target keeps holding SDA and the bus stays stuck until a
power cycle of this i2c controller.
Accept count=0: NACK the in-flight dummy byte (TXAK) and set msg->len to
2 so i2c_imx_isr_read_continue() emits STOP via its normal last-byte
path. The dummy byte is discarded; block-read callers only consume
buf[0..count-1].
Reading I2DR has likewise already armed the next byte on the
count > I2C_SMBUS_BLOCK_MAX error path, so NACK it (TXAK) before aborting
with -EPROTO; otherwise the failing transfer's STOP cannot complete and
the bus stays held.
The atomic path regressed earlier (v3.16) and is fixed separately; this
patch covers only the v6.13 state-machine rework. |
| In the Linux kernel, the following vulnerability has been resolved:
platform/x86/intel/tpmi: use cleanup helpers in mem_write()
In mem_write(), the temporary array returned by
parse_int_array_user() must be released on all exit paths.
Convert the array variable to use cleanup.h scope-based
cleanup so it is freed automatically on return.
This also moves the array declaration next to
parse_int_array_user() as required by cleanup.h usage
guidelines. |
| In the Linux kernel, the following vulnerability has been resolved:
dmaengine: sh: rz-dmac: Move interrupt request after everything is set up
Once the interrupt is requested, the interrupt handler may run immediately.
Since the IRQ handler can access channel->ch_base, which is initialized
only after requesting the IRQ, this may lead to invalid memory access.
Likewise, the IRQ thread may access uninitialized data (the ld_free,
ld_queue, and ld_active lists), which may also lead to issues.
Request the interrupts only after everything is set up. To keep the error
path simpler, use dmam_alloc_coherent() instead of dma_alloc_coherent(). |
