| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
mptcp: pm: ADD_ADDR rtx: always decrease sk refcount
When an ADD_ADDR is retransmitted, the sk is held in sk_reset_timer().
It should then be released in all cases at the end.
Some (unlikely) checks were returning directly instead of calling
sock_put() to decrease the refcount. Jump to a new 'exit' label to call
__sock_put() (which will become sock_put() in the next commit) to fix
this potential leak.
While at it, drop the '!msk' check which cannot happen because it is
never reset, and explicitly mark the remaining one as "unlikely". |
| In the Linux kernel, the following vulnerability has been resolved:
PCI/P2PDMA: Fix p2pmem_alloc_mmap() warning condition
Commit b7e282378773 has already changed the initial page refcount of
p2pdma page from one to zero, however, in p2pmem_alloc_mmap() it uses
"VM_WARN_ON_ONCE_PAGE(!page_ref_count(page))" to assert the initial page
refcount should not be zero and the following will be reported when
CONFIG_DEBUG_VM is enabled:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x380400000
flags: 0x20000000002000(reserved|node=0|zone=4)
raw: 0020000000002000 ff1100015e3ab440 0000000000000000 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: VM_WARN_ON_ONCE_PAGE(!page_ref_count(page))
------------[ cut here ]------------
WARNING: CPU: 5 PID: 449 at drivers/pci/p2pdma.c:240 p2pmem_alloc_mmap+0x83a/0xa60
Fix by using "page_ref_count(page)" as the assertion condition. |
| libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_GetBuffer, XML_Parse, XML_ParseBuffer, XML_ParserFree, or XML_ParserReset from within handlers in cases of a policy violation. Thus, a use-after-free can occur, |
| In the Linux kernel, the following vulnerability has been resolved:
dm-thin: fix metadata refcount underflow
There's a bug in dm-thin in the function rebalance_children. If the
internal btree node has one entry, the code tries to copy all btree
entries from the node's child to the node itself and then decrement the
child's reference count.
If the child node is shared (it has reference count > 1), we won't free
it, so there would be two pointers to each of the grandchildren nodes.
But the reference counts of the grandchildren is not increased, thus the
reference count doesn't match the number of pointers that point to the
grandchildren. This results in "device mapper: space map common: unable
to decrement block" errors.
Fix this bug by incrementing reference counts on the grandchildren if the
btree node is shared. |
| In the Linux kernel, the following vulnerability has been resolved:
net: ipv6: fix NOREF dst use in seg6 and rpl lwtunnels
seg6_input_core() and rpl_input() call ip6_route_input() which sets a
NOREF dst on the skb, then pass it to dst_cache_set_ip6() invoking
dst_hold() unconditionally.
On PREEMPT_RT, ksoftirqd is preemptible and a higher-priority task can
release the underlying pcpu_rt between the lookup and the caching
through a concurrent FIB lookup on a shared nexthop.
Simplified race sequence:
ksoftirqd/X higher-prio task (same CPU X)
----------- --------------------------------
seg6_input_core(,skb)/rpl_input(skb)
dst_cache_get()
-> miss
ip6_route_input(skb)
-> ip6_pol_route(,skb,flags)
[RT6_LOOKUP_F_DST_NOREF in flags]
-> FIB lookup resolves fib6_nh
[nhid=N route]
-> rt6_make_pcpu_route()
[creates pcpu_rt, refcount=1]
pcpu_rt->sernum = fib6_sernum
[fib6_sernum=W]
-> cmpxchg(fib6_nh.rt6i_pcpu,
NULL, pcpu_rt)
[slot was empty, store succeeds]
-> skb_dst_set_noref(skb, dst)
[dst is pcpu_rt, refcount still 1]
rt_genid_bump_ipv6()
-> bumps fib6_sernum
[fib6_sernum from W to Z]
ip6_route_output()
-> ip6_pol_route()
-> FIB lookup resolves fib6_nh
[nhid=N]
-> rt6_get_pcpu_route()
pcpu_rt->sernum != fib6_sernum
[W <> Z, stale]
-> prev = xchg(rt6i_pcpu, NULL)
-> dst_release(prev)
[prev is pcpu_rt,
refcount 1->0, dead]
dst = skb_dst(skb)
[dst is the dead pcpu_rt]
dst_cache_set_ip6(dst)
-> dst_hold() on dead dst
-> WARN / use-after-free
For the race to occur, ksoftirqd must be preemptible (PREEMPT_RT without
PREEMPT_RT_NEEDS_BH_LOCK) and a concurrent task must be able to release
the pcpu_rt. Shared nexthop objects provide such a path, as two routes
pointing to the same nhid share the same fib6_nh and its rt6i_pcpu
entry.
Fix seg6_input_core() and rpl_input() by calling skb_dst_force() after
ip6_route_input() to force the NOREF dst into a refcounted one before
caching.
The output path is not affected as ip6_route_output() already returns a
refcounted dst. |
| In the Linux kernel, the following vulnerability has been resolved:
smb: server: fix active_num_conn leak on transport allocation failure
Commit 77ffbcac4e56 ("smb: server: fix leak of active_num_conn in
ksmbd_tcp_new_connection()") addressed the kthread_run() failure
path. The earlier alloc_transport() == NULL path in the same
function has the same leak, is reachable pre-authentication via any
TCP connect to port 445, and was empirically reproduced on UML
(ARCH=um, v7.0-rc7): a small number of forced allocation failures
were sufficient to put ksmbd into a state where every subsequent
connection attempt was rejected for the remainder of the boot.
ksmbd_kthread_fn() increments active_num_conn before calling
ksmbd_tcp_new_connection() and discards the return value, so when
alloc_transport() returns NULL the socket is released and -ENOMEM
returned without decrementing the counter. Each such failure
permanently consumes one slot from the max_connections pool; once
cumulative failures reach the cap, atomic_inc_return() hits the
threshold on every subsequent accept and every new connection is
rejected. The counter is only reset by module reload.
An unauthenticated remote attacker can drive the server toward the
memory pressure that makes alloc_transport() fail by holding open
connections with large RFC1002 lengths up to MAX_STREAM_PROT_LEN
(0x00FFFFFF); natural transient allocation failures on a loaded
host produce the same drift more slowly.
Mirror the existing rollback pattern in ksmbd_kthread_fn(): on the
alloc_transport() failure path, decrement active_num_conn gated on
server_conf.max_connections.
Repro details: with the patch reverted, forced alloc_transport()
NULL returns leaked counter slots and subsequent connection
attempts -- including legitimate connects issued after the
forced-fail window had closed -- were all rejected with "Limit the
maximum number of connections". With this patch applied, the same
connect sequence produces no rejections and the counter cycles
cleanly between zero and one on every accept. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/i915/gt: fix refcount underflow in intel_engine_park_heartbeat
A use-after-free / refcount underflow is possible when the heartbeat
worker and intel_engine_park_heartbeat() race to release the same
engine->heartbeat.systole request.
The heartbeat worker reads engine->heartbeat.systole and calls
i915_request_put() on it when the request is complete, but clears
the pointer in a separate, non-atomic step. Concurrently, a request
retirement on another CPU can drop the engine wakeref to zero, triggering
__engine_park() -> intel_engine_park_heartbeat(). If the heartbeat
timer is pending at that point, cancel_delayed_work() returns true and
intel_engine_park_heartbeat() reads the stale non-NULL systole pointer
and calls i915_request_put() on it again, causing a refcount underflow:
```
<4> [487.221889] Workqueue: i915-unordered engine_retire [i915]
<4> [487.222640] RIP: 0010:refcount_warn_saturate+0x68/0xb0
...
<4> [487.222707] Call Trace:
<4> [487.222711] <TASK>
<4> [487.222716] intel_engine_park_heartbeat.part.0+0x6f/0x80 [i915]
<4> [487.223115] intel_engine_park_heartbeat+0x25/0x40 [i915]
<4> [487.223566] __engine_park+0xb9/0x650 [i915]
<4> [487.223973] ____intel_wakeref_put_last+0x2e/0xb0 [i915]
<4> [487.224408] __intel_wakeref_put_last+0x72/0x90 [i915]
<4> [487.224797] intel_context_exit_engine+0x7c/0x80 [i915]
<4> [487.225238] intel_context_exit+0xf1/0x1b0 [i915]
<4> [487.225695] i915_request_retire.part.0+0x1b9/0x530 [i915]
<4> [487.226178] i915_request_retire+0x1c/0x40 [i915]
<4> [487.226625] engine_retire+0x122/0x180 [i915]
<4> [487.227037] process_one_work+0x239/0x760
<4> [487.227060] worker_thread+0x200/0x3f0
<4> [487.227068] ? __pfx_worker_thread+0x10/0x10
<4> [487.227075] kthread+0x10d/0x150
<4> [487.227083] ? __pfx_kthread+0x10/0x10
<4> [487.227092] ret_from_fork+0x3d4/0x480
<4> [487.227099] ? __pfx_kthread+0x10/0x10
<4> [487.227107] ret_from_fork_asm+0x1a/0x30
<4> [487.227141] </TASK>
```
Fix this by replacing the non-atomic pointer read + separate clear with
xchg() in both racing paths. xchg() is a single indivisible hardware
instruction that atomically reads the old pointer and writes NULL. This
guarantees only one of the two concurrent callers obtains the non-NULL
pointer and performs the put, the other gets NULL and skips it.
(cherry picked from commit 13238dc0ee4f9ab8dafa2cca7295736191ae2f42) |
| In the Linux kernel, the following vulnerability has been resolved:
rxrpc: fix reference count leak in rxrpc_server_keyring()
This patch fixes a reference count leak in rxrpc_server_keyring()
by checking if rx->securities is already set. |
| In the Linux kernel, the following vulnerability has been resolved:
nfc: llcp: add missing return after LLCP_CLOSED checks
In nfc_llcp_recv_hdlc() and nfc_llcp_recv_disc(), when the socket
state is LLCP_CLOSED, the code correctly calls release_sock() and
nfc_llcp_sock_put() but fails to return. Execution falls through to
the remainder of the function, which calls release_sock() and
nfc_llcp_sock_put() again. This results in a double release_sock()
and a refcount underflow via double nfc_llcp_sock_put(), leading to
a use-after-free.
Add the missing return statements after the LLCP_CLOSED branches
in both functions to prevent the fall-through. |
| In the Linux kernel, the following vulnerability has been resolved:
media: vidtv: fix nfeeds state corruption on start_streaming failure
syzbot reported a memory leak in vidtv_psi_service_desc_init [1].
When vidtv_start_streaming() fails inside vidtv_start_feed(), the
nfeeds counter is left incremented even though no feed was actually
started. This corrupts the driver state: subsequent start_feed calls
see nfeeds > 1 and skip starting the mux, while stop_feed calls
eventually try to stop a non-existent stream.
This state corruption can also lead to memory leaks, since the mux
and channel resources may be partially allocated during a failed
start_streaming but never cleaned up, as the stop path finds
dvb->streaming == false and returns early.
Fix by decrementing nfeeds back when start_streaming fails, keeping
the counter in sync with the actual number of active feeds.
[1]
BUG: memory leak
unreferenced object 0xffff888145b50820 (size 32):
comm "syz.0.17", pid 6068, jiffies 4294944486
backtrace (crc 90a0c7d4):
vidtv_psi_service_desc_init+0x74/0x1b0 drivers/media/test-drivers/vidtv/vidtv_psi.c:288
vidtv_channel_s302m_init+0xb1/0x2a0 drivers/media/test-drivers/vidtv/vidtv_channel.c:83
vidtv_channels_init+0x1b/0x40 drivers/media/test-drivers/vidtv/vidtv_channel.c:524
vidtv_mux_init+0x516/0xbe0 drivers/media/test-drivers/vidtv/vidtv_mux.c:518
vidtv_start_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:194 [inline]
vidtv_start_feed+0x33e/0x4d0 drivers/media/test-drivers/vidtv/vidtv_bridge.c:239 |
| In the Linux kernel, the following vulnerability has been resolved:
gfs2: Fix slab-use-after-free in qd_put
Commit a475c5dd16e5 ("gfs2: Free quota data objects synchronously")
started freeing quota data objects during filesystem shutdown instead of
putting them back onto the LRU list, but it failed to remove these
objects from the LRU list, causing LRU list corruption. This caused
use-after-free when the shrinker (gfs2_qd_shrink_scan) tried to access
already-freed objects on the LRU list.
Fix this by removing qd objects from the LRU list before freeing them in
qd_put().
Initial fix from Deepanshu Kartikey <kartikey406@gmail.com>. |
| In the Linux kernel, the following vulnerability has been resolved:
fs: afs: revert mmap_prepare() change
Partially reverts commit 9d5403b1036c ("fs: convert most other
generic_file_*mmap() users to .mmap_prepare()").
This is because the .mmap invocation establishes a refcount, but
.mmap_prepare is called at a point where a merge or an allocation failure
might happen after the call, which would leak the refcount increment.
Functionality is being added to permit the use of .mmap_prepare in this
case, but in the interim, we need to fix this. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix a potential use-after-free of BTF object
Refcounting in the check_pseudo_btf_id() function is incorrect:
the __check_pseudo_btf_id() function might get called with a zero
refcounted btf. Fix this, and patch related code accordingly.
v3: rephrase a comment (AI)
v2: fix a refcount leak introduced in v1 (AI) |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Preserve id of register in sync_linked_regs()
sync_linked_regs() copies the id of known_reg to reg when propagating
bounds of known_reg to reg using the off of known_reg, but when
known_reg was linked to reg like:
known_reg = reg ; both known_reg and reg get same id
known_reg += 4 ; known_reg gets off = 4, and its id gets BPF_ADD_CONST
now when a call to sync_linked_regs() happens, let's say with the following:
if known_reg >= 10 goto pc+2
known_reg's new bounds are propagated to reg but now reg gets
BPF_ADD_CONST from the copy.
This means if another link to reg is created like:
another_reg = reg ; another_reg should get the id of reg but
assign_scalar_id_before_mov() sees
BPF_ADD_CONST on reg and assigns a new id to it.
As reg has a new id now, known_reg's link to reg is broken. If we find
new bounds for known_reg, they will not be propagated to reg.
This can be seen in the selftest added in the next commit:
0: (85) call bpf_get_prandom_u32#7 ; R0=scalar()
1: (57) r0 &= 255 ; R0=scalar(smin=smin32=0,smax=umax=smax32=umax32=255,var_off=(0x0; 0xff))
2: (bf) r1 = r0 ; R0=scalar(id=1,smin=smin32=0,smax=umax=smax32=umax32=255,var_off=(0x0; 0xff)) R1=scalar(id=1,smin=smin32=0,smax=umax=smax32=umax32=255,var_off=(0x0; 0xff))
3: (07) r1 += 4 ; R1=scalar(id=1+4,smin=umin=smin32=umin32=4,smax=umax=smax32=umax32=259,var_off=(0x0; 0x1ff))
4: (a5) if r1 < 0xa goto pc+4 ; R1=scalar(id=1+4,smin=umin=smin32=umin32=10,smax=umax=smax32=umax32=259,var_off=(0x0; 0x1ff))
5: (bf) r2 = r0 ; R0=scalar(id=2,smin=umin=smin32=umin32=6,smax=umax=smax32=umax32=255) R2=scalar(id=2,smin=umin=smin32=umin32=6,smax=umax=smax32=umax32=255)
6: (a5) if r1 < 0xe goto pc+2 ; R1=scalar(id=1+4,smin=umin=smin32=umin32=14,smax=umax=smax32=umax32=259,var_off=(0x0; 0x1ff))
7: (35) if r0 >= 0xa goto pc+1 ; R0=scalar(id=2,smin=umin=smin32=umin32=6,smax=umax=smax32=umax32=9,var_off=(0x0; 0xf))
8: (37) r0 /= 0
div by zero
When 4 is verified, r1's bounds are propagated to r0 but r0 also gets
BPF_ADD_CONST (bug).
When 5 is verified, r0 gets a new id (2) and its link with r1 is broken.
After 6 we know r1 has bounds [14, 259] and therefore r0 should have
bounds [10, 255], therefore the branch at 7 is always taken. But because
r0's id was changed to 2, r1's new bounds are not propagated to r0.
The verifier still thinks r0 has bounds [6, 255] before 7 and execution
can reach div by zero.
Fix this by preserving id in sync_linked_regs() like off and subreg_def. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/rxe: Fix race condition in QP timer handlers
I encontered the following warning:
WARNING: drivers/infiniband/sw/rxe/rxe_task.c:249 at rxe_sched_task+0x1c8/0x238 [rdma_rxe], CPU#0: swapper/0/0
...
libsha1 [last unloaded: ip6_udp_tunnel]
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G C 6.19.0-rc5-64k-v8+ #37 PREEMPT
Tainted: [C]=CRAP
Hardware name: Raspberry Pi 4 Model B Rev 1.2
Call trace:
rxe_sched_task+0x1c8/0x238 [rdma_rxe] (P)
retransmit_timer+0x130/0x188 [rdma_rxe]
call_timer_fn+0x68/0x4d0
__run_timers+0x630/0x888
...
WARNING: drivers/infiniband/sw/rxe/rxe_task.c:38 at rxe_sched_task+0x1c0/0x238 [rdma_rxe], CPU#0: swapper/0/0
...
WARNING: drivers/infiniband/sw/rxe/rxe_task.c:111 at do_work+0x488/0x5c8 [rdma_rxe], CPU#3: kworker/u17:4/93400
...
refcount_t: underflow; use-after-free.
WARNING: lib/refcount.c:28 at refcount_warn_saturate+0x138/0x1a0, CPU#3: kworker/u17:4/93400
The issue is caused by a race condition between retransmit_timer() and
rxe_destroy_qp, leading to the Queue Pair's (QP) reference count dropping
to zero during timer handler execution.
It seems this warning is harmless because rxe_qp_do_cleanup() will flush
all pending timers and requests.
Example of flow causing the issue:
CPU0 CPU1
retransmit_timer() {
spin_lock_irqsave
rxe_destroy_qp()
__rxe_cleanup()
__rxe_put() // qp->ref_count decrease to 0
rxe_qp_do_cleanup() {
if (qp->valid) {
rxe_sched_task() {
WARN_ON(rxe_read(task->qp) <= 0);
}
}
spin_unlock_irqrestore
}
spin_lock_irqsave
qp->valid = 0
spin_unlock_irqrestore
}
Ensure the QP's reference count is maintained and its validity is checked
within the timer callbacks by adding calls to rxe_get(qp) and corresponding
rxe_put(qp) after use. |
| In the Linux kernel, the following vulnerability has been resolved:
accel/ivpu: Disallow re-exporting imported GEM objects
Prevent re-exporting of imported GEM buffers by adding a custom
prime_handle_to_fd callback that checks if the object is imported
and returns -EOPNOTSUPP if so.
Re-exporting imported GEM buffers causes loss of buffer flags settings,
leading to incorrect device access and data corruption. |
| In the Linux kernel, the following vulnerability has been resolved:
nfc: pn533: properly drop the usb interface reference on disconnect
When the device is disconnected from the driver, there is a "dangling"
reference count on the usb interface that was grabbed in the probe
callback. Fix this up by properly dropping the reference after we are
done with it. |
| In the Linux kernel, the following vulnerability has been resolved:
PCI/P2PDMA: Release per-CPU pgmap ref when vm_insert_page() fails
When vm_insert_page() fails in p2pmem_alloc_mmap(), p2pmem_alloc_mmap()
doesn't invoke percpu_ref_put() to free the per-CPU ref of pgmap acquired
after gen_pool_alloc_owner(), and memunmap_pages() will hang forever when
trying to remove the PCI device.
Fix it by adding the missed percpu_ref_put(). |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: inside-secure/eip93 - fix kernel panic in driver detach
During driver detach, the same hash algorithm is unregistered multiple
times due to a wrong iterator. |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: fix dirtyclusters double decrement on fs shutdown
fstests test generic/388 occasionally reproduces a warning in
ext4_put_super() associated with the dirty clusters count:
WARNING: CPU: 7 PID: 76064 at fs/ext4/super.c:1324 ext4_put_super+0x48c/0x590 [ext4]
Tracing the failure shows that the warning fires due to an
s_dirtyclusters_counter value of -1. IOW, this appears to be a
spurious decrement as opposed to some sort of leak. Further tracing
of the dirty cluster count deltas and an LLM scan of the resulting
output identified the cause as a double decrement in the error path
between ext4_mb_mark_diskspace_used() and the caller
ext4_mb_new_blocks().
First, note that generic/388 is a shutdown vs. fsstress test and so
produces a random set of operations and shutdown injections. In the
problematic case, the shutdown triggers an error return from the
ext4_handle_dirty_metadata() call(s) made from
ext4_mb_mark_context(). The changed value is non-zero at this point,
so ext4_mb_mark_diskspace_used() does not exit after the error
bubbles up from ext4_mb_mark_context(). Instead, the former
decrements both cluster counters and returns the error up to
ext4_mb_new_blocks(). The latter falls into the !ar->len out path
which decrements the dirty clusters counter a second time, creating
the inconsistency.
To avoid this problem and simplify ownership of the cluster
reservation in this codepath, lift the counter reduction to a single
place in the caller. This makes it more clear that
ext4_mb_new_blocks() is responsible for acquiring cluster
reservation (via ext4_claim_free_clusters()) in the !delalloc case
as well as releasing it, regardless of whether it ends up consumed
or returned due to failure. |
