| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: sfq: clamp quantum in change path
sfq_change() accepts any non-negative quantum (only rejects
(int)ctl->quantum < 0). With a crafted size table qdisc_pkt_len reaches
~2 GiB, so quantum=1 makes the deficit-refill loop spin ~2^31 times
under the qdisc lock (a soft lockup / denial of service).
Add max(256U, ...) matching fq_codel_change(). Reject quantum > 1<<20
with -EINVAL, matching fq_codel_change() and the init clamp.
Conditions to recreate the bug:
CONFIG_NET_SCH_SFQ=y. Requires CAP_NET_ADMIN (namespace-local via
unshare -Urn suffices).
tc qdisc add dev dummy0 root sfq
tc qdisc change dev dummy0 root sfq quantum 1 stab data 32768 size_log 15 cell_log 0 |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: fq_pie: clamp quantum in change path
fq_pie_change() accepts any quantum value from userspace, including 1.
With a crafted size table qdisc_pkt_len reaches ~2 GiB, so quantum=1
makes the deficit-refill loop spin ~2^31 times under the qdisc lock
(a soft lockup / denial of service).
Add max(256U, ...) matching fq_codel_change().
Conditions to recreate the bug:
CONFIG_NET_SCH_FQ_PIE=y. Requires CAP_NET_ADMIN (namespace-local via
unshare -Urn suffices).
tc qdisc add dev dummy0 root fq_pie
tc qdisc change dev dummy0 root fq_pie quantum 1 stab data 32768 size_log 15 cell_log 0 |
| In the Linux kernel, the following vulnerability has been resolved:
eth: nfp: drop the replaced rule from the list when reprogramming fails
nfp_net_fs_add() replaces an existing rule by deleting it from the
hardware, decrementing nn->fs.count and programming the new one. If
nfp_net_fs_add_hw() fails the old entry stays on nn->fs.list - only the
success path reaches list_replace() - so the list is one longer than
nn->fs.count, and it advertises a rule whose hardware entry has already
been torn down.
nn->fs.count is what ETHTOOL_GRXCLSRLCNT reports, so userspace then sizes
its buffer one entry short of what the GRXCLSRLALL walk wants to write.
That used to overwrite one u32 past the allocation; since the walk is
bounded it is a permanent -EMSGSIZE instead, as nothing ever resyncs the
counter. |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: fix a TOCTOU race in SCTP_CMD_TIMER_START
The SCTP_CMD_TIMER_START handler checks timer_pending() before calling
timer_reduce(). The timer can expire and detach between these operations,
causing timer_reduce() to rearm the timer without taking the association
reference required for the newly armed timer.
The timer callback later unconditionally drops its association reference,
which can leave the association reference count unbalanced and result in
use-after-free during association teardown.
Use the return value of timer_reduce() to determine whether the timer was
actually armed. Take the association reference only when timer_reduce()
successfully starts a new timer, closing the race between checking the
timer state and rearming it.
This issue was reported by Nico Yip (@_cyeaa_) working with TrendAI Zero
Day Initiative. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: don't downgrade half-dead scalar zero spills to STACK_ZERO
states.c:__clean_func_state() can downgrade scalar zero spill to
STACK_ZERO in the following case:
*(u64 *)(r10 - 8) = 0;
... checkpoint ...
r1 = *(u32 *)(r10 - 4);
... no reads from r10-8 ...
Here 4 bytes at r10-8 are dead and verifier changes scalar spill to a
combination: 0000pppp (p stands for poison). Such a change breaks
precision propagation chains. All places that produce STACK_ZERO
should call bpf_mark_chain_precision() for the zero source.
This patch fixes the bug in a simplest way possible:
avoids converting stack spills of zero to STACK_ZERO.
Two smarter approaches are possible:
- do bpf_mark_chain_precision() from __clean_func_state()
- check slot liveness information in check_stack_write_fixed_off()
I investigated both and the changes required are a bit tricky,
hence go with a simple fix for the time being. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Preserve special fields in recycled rhtab elements
rhtab_map_update_elem() initializes special fields after obtaining an
element from bpf_mem_cache_alloc(). The allocator can return a fresh,
zeroed unit, or recycle one from its RCU-pending lists before the
registered destructor has run.
A BPF program can retain a map-value pointer after deleting its element
and initialize and arm a timer through that pointer. If the deleted unit
is recycled, check_and_init_map_value() clears the only pointer to the
timer. Neither a later deletion nor rhtab_mem_dtor() can then cancel it,
and the callback can run with its key and value pointing into freed memory.
Do not reinitialize special fields on insertion. Fresh allocator units are
already zeroed. For recycled units, the special fields are ownership state
that must remain visible to the eventual destructor. copy_map_value()
already skips those fields, matching the non-preallocated hash-map path and
the lifecycle established by commit 275c30bcee66 ("bpf: Don't reinit map
value in prealloc_lru_pop").
[ kkd: Split out the fix and rewrote the commit log ] |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Don't predict JMP32 pointer vs zero comparisons
Consider the following program:
r1 = map_value; /* low 32 bits are zero at runtime */
r6 = 0xdead000000000000;
if w1 != 0 goto l1;
l0: r1 += r6;
r2 = *(u64 *)(r1 + 0);
exit;
l1: r6 = 0;
goto l0;
At the moment is_branch_taken() reports the jump as always taken,
because it does not distinguish between BPF_JMP and BPF_JMP32
comparisons when processing 'if w1 != 0 ...'. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: zero extend the result of an arena 32-bit cmpxchg
bpf_convert_ctx_accesses() rewrites an atomic on an arena pointer from
BPF_STX | BPF_ATOMIC to BPF_STX | BPF_PROBE_ATOMIC, and it runs before
bpf_opt_subreg_zext_lo32_rnd_hi32().
That pass emits an explicit zero extension for a 32-bit cmpxchg even
when bpf_jit_needs_zext() is false. This is done because on some
architectures 32-bit cmpxchg requires explicit zero extension for the
dst register. E.g. on x86-64 'lock cmpxchg' does not change the %eax
if comparison is successful, while BPF semantics declare that each
operation on a 32-bit register zero extends it's upper half.
is_cmpxchg_insn() matches BPF_MODE == BPF_ATOMIC only, so an arena
cmpxchg misses said zero extension adjustment. This patch adjusts
is_cmpxchg_insn() to match BPF_PROBE_ATOMIC alongside BPF_ATOMIC. |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: Intel: avs: Fix unbalanced module reference count
strace_open() invokes try_module_get() which on success takes
the module reference. If any follow up operation causes
strace_open() to fail, the refcount shall be put down. |
| In the Linux kernel, the following vulnerability has been resolved:
ring-buffer: Add checking nr_subbufs to persistent ring buffer validation
Sashiko reported that the code was using meta->nr_subbufs without making
sure that it matched the nr_pages + 1 on data that was assuming the two
were the same.
Add a check to the persistent ring buffer validation code to make sure
that the saved nr_subbufs matches what we expect. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Reject tail calls directly from callback frames
A tail call from a non-zero frame is modeled as a return from that frame.
The verifier makes R0 unknown and calls prepare_func_exit() for the taken
branch.
When the current frame is a synchronous callback, prepare_func_exit()
enforces the callback return-value contract and marks R0 precise. Since the
tail-call path synthesized R0 rather than deriving it from an instruction,
precision backtracking reaches the callback-calling instruction with R0
still requested and triggers the "callback unexpected regs" verifier bug.
A CAP_BPF task can therefore cause a WARN and an -EFAULT BPF_PROG_LOAD.
Tail calls reachable from callbacks are already rejected later by
check_max_stack_depth(). Reject a tail call made directly by a callback
before constructing the inconsistent return state, using the existing
diagnostic. Tail calls from ordinary subprograms keep their current
behavior. |
| In the Linux kernel, the following vulnerability has been resolved:
ntfs: propagate reparse index insertion failure
update_reparse_data() ignores the return value of
set_reparse_index(). When index insertion fails, the code removes
the just-written reparse data as cleanup but still returns 0, so
symlink(2) (and WSL special file creation) reports success while
no reparse data exists on disk. When there was no previous reparse
data (oldsize == 0), the failure was likewise silently ignored.
Propagate the error to the caller. |
| In the Linux kernel, the following vulnerability has been resolved:
accel: ethosu: Don't read the U65 rounding mode as a storage mode
Bits 15:14 of NPU_SET_{IFM,OFM}_PRECISION select the activation storage
mode on U85 only. On U65 the same field holds the rounding mode, and the
command stream parser has read it as a storage mode since the driver was
added.
That went unnoticed while unknown values fell through the switch, but
now that they are rejected, every U65 command stream that asks for
natural rounding (2) fails CMDSTREAM_BO_CREATE with -EINVAL. Mesa emits
it for average pooling, concatenation, split, unpack, strided slice, LUT
and argmax, which is 72 failures of the Teflon test suite on an i.MX93.
Truncating rounding (1) is misread as well: it picks the two-tile
address path and computes a bogus feature map size from tile bases the
command stream never set.
Read the field as a storage mode only on the hardware where it is one. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix REG INVARIANTS VIOLATION on speculative pointer arithmetic
Take the following unprivileged program as an example:
r0 = bpf_map_lookup_elem(...) /* PTR_TO_MAP_VALUE, offset 0 */
...
14: r0 += r1 /* r1 is a bounded scalar */
15: r9 = r0
Loading it triggers a verifier warning from reg_bounds_sanity_check():
verifier bug: REG INVARIANTS VIOLATION (alu): const subreg tnum out
of sync with range bounds r64={.base=0x0, .size=0x0}
r32={.base=0x0, .size=0xffffffff} var_off=(0x0, 0x0)
What happens:
1. Processing insn 14 (r0 += r1) in adjust_ptr_min_max_vals(), the new
offset is computed into dst_reg's var_off and 32/64-bit ranges.
2. Because pointer registers do not track 32-bit subregister bounds,
__mark_reg32_unbounded() first sets r32 to the full range; r32 is
re-derived from the offset at the end of the function by
reg_bounds_sync().
3. On the unprivileged path, sanitize_ptr_alu() is called and, via
sanitize_speculative_path() -> push_stack(), snapshots the current
register state and schedules the next instruction (insn 15) to be
verified directly as a speculative path.
4. That snapshot is taken between step 2 and the final reg_bounds_sync():
at this point dst_reg's var_off still holds the (const) original
offset while r32 has just been blanked to the full range, i.e. the two
are out of sync. When the speculative path later verifies insn 15
(r9 = r0), the inconsistent state reaches reg_bounds_sanity_check() and
trips the warning.
var_off and the 32-bit range must always be consistent. There are two
ways to keep the snapshot consistent:
1. sync var_off and r32 before the snapshot so they match, or
2. leave r32 at its original (already consistent) value and blank it
only after the snapshot.
The whole point of sanitize_ptr_alu() is to insert a harmless masking
sequence that keeps the access in bounds under speculation, so the state
it snapshots should faithfully represent that. Take approach 2: move
__mark_reg32_unbounded() to after sanitize_ptr_alu(), so the speculative
snapshot keeps the pointer's original, consistent r32. The non-speculative
path is unchanged: r32 is still blanked before the offset is applied and
re-derived by reg_bounds_sync(). |
| In the Linux kernel, the following vulnerability has been resolved:
accel/amdxdna: reject a command chain that carries no commands
A chain whose command_count is zero passes the payload length check,
because struct_size(payload, data, 0) is just the header. The fill loop
then does not run, so offset stays zero and the request is submitted with
a zero-length buffer.
On firmware without AIE2_NPU_COMMAND that ends at the opcode check, since
op is still ERT_INVALID_CMD and aie2_get_chain_msg_op() answers
MSG_OP_MAX_OPCODE. aie2_get_npu_chain_msg_op() answers
MSG_OP_CHAIN_EXEC_NPU whatever it is given, so there the submission
continues to drm_clflush_virt_range(cmd_buf, 0), which reads the byte
before the buffer and faults on the vmap guard page. EXEC_CMD is
reachable by any process that can open the render node.
Reject the request instead. |
| In the Linux kernel, the following vulnerability has been resolved:
ppp_async: drop the errored frame instead of resetting its headroom
ppp_receive_nonmp_frame() prepends a two-byte direction tag before running
the pass/active BPF filters:
*(__be16 *)skb_push(skb, 2) = htons(PPP_FILTER_INBOUND_TAG);
Nothing on the receive path guarantees those two bytes of headroom. The
frame-error path in ppp_async's process_input_packet() resets a reused skb's
headroom to zero while claiming to restore it to a freshly allocated state -
but a fresh skb from dev_alloc_skb() carries NET_SKB_PAD:
err:
if (skb) {
/* make skb appear as freshly allocated */
skb_trim(skb, 0);
skb_reserve(skb, - skb_headroom(skb));
}
ap->rpkt still points at that skb, so the next frame is reassembled into it
with no headroom at all. A peer that sends a bad-FCS frame followed by one
beginning ff 03 then leaves a single byte of headroom by the time the filter
tag is pushed, which lands one byte below skb->head:
skbuff: skb_under_panic: len:49 put:2 head:ffff888003c10000
data:ffff888003c0ffff tail:0x30 end:0x640 dev:<NULL>
kernel BUG at net/core/skbuff.c:214!
RIP: 0010:skb_panic+0x13e/0x230
Call Trace:
skb_push+0xbd/0x100
ppp_receive_nonmp_frame+0x48a/0x1d10
ppp_input+0x4e9/0x2f80
ppp_async_process+0x2a/0xe0
tasklet_action_common+0x20f/0x8a0
handle_softirqs+0x18e/0x590
Kernel panic - not syncing: Fatal exception in interrupt
Zeroing the headroom violates the NET_SKB_PAD guarantee that dev_alloc_skb()
gives the rest of the receive path. Besides the filter panic above, when CCP
compression is enabled ppp_decompress_frame() hands skb->data - 2 to
->decompress()/->incomp(), which then reads out of bounds before skb->head
for the same reason.
Rather than restore the headroom, drop the errored frame - as ppp_synctty
already does on its error path - and clear ap->rpkt so the next frame is
reassembled into a fresh skb with proper headroom. This is simpler and fixes
both the filter under-panic and the CCP out-of-bounds read.
The original V1 of this patch made room in ppp_receive_nonmp_frame() with
skb_cow_head(); Eric pointed out that fixing the root cause in the transport
is the right approach.
Found by fuzzing the PPP receive path with a mutating peer on a pty; it is an
interesting (remote) DoS: root configures PPP, the peer supplies two crashing
frames. The reproducer (repro-ppp-skb.c, unchanged from v1) panics in about a
second, and returns cleanly with this applied. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7921: validate CLC firmware records
The CLC region is supplied by firmware, but the loader trusts the
region count and each record length. A malformed image can make the
region table pointer precede the firmware buffer, make the record loop
fail to advance, or index phy->clc past its end. Validate the table and
record bounds before dereferencing or copying. |
| In the Linux kernel, the following vulnerability has been resolved:
nvdimm: pmem: keep PREFLUSH before data writes
pmem_submit_bio() records a REQ_PREFLUSH error, but continues to copy the
bio data and can later overwrite the error with a successful REQ_FUA flush.
That lets data writes run after a failed preflush and can complete the bio
successfully despite the failed ordering barrier.
Run the REQ_PREFLUSH flush synchronously before touching the bio data and
complete the bio with the flush error if it fails. Keep asynchronous flush
chaining for REQ_FUA. At that point, data copy has completed and the parent
bio can wait for the chained flush bio. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: fix out-of-bounds write in l2cap_ecred_connect
l2cap_chan_connect() tries to ensure there are no more than
L2CAP_ECRED_CONN_SCID_MAX pending ECRED channels, so they fit in the
same L2CAP_ECRED_CONN_REQ that l2cap_ecred_connect() constructs.
However, the check only counts deferred channels. If 6 L2CAP sockets
are connected at the same time in order DDDDND (D=deferred,
N=non-deferred), the last can bump the total to max+1. It results to
one __le16 written out of bounds of the scid array, and an invalid
ECRED_CONN_REQ being sent.
Fix by leaving room for the non-deferred pending ECRED channels in the
counting in l2cap_chan_connect(), so the limit can't be exceeded.
Move counting under same critical section where the channel is added.
Although race conditions involving this appear unreachable, it's easier
to see.
Also add WARN_ON_ONCE check in l2cap_ecred_defer_connect() to make this
less brittle. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: rate limit unmapped SID errors
A client can include many structurally valid but unmapped SIDs in a DACL.
Logging every mapping failure lets one request generate hundreds of kernel
error messages.
Rate limit the message to prevent an authenticated client from flooding
the kernel log. |
