| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| 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:
net/mlx5e: RX, Fix XDP multi-buf frag counting for striding RQ
XDP multi-buf programs can modify the layout of the XDP buffer when the
program calls bpf_xdp_pull_data() or bpf_xdp_adjust_tail(). The
referenced commit in the fixes tag corrected the assumption in the mlx5
driver that the XDP buffer layout doesn't change during a program
execution. However, this fix introduced another issue: the dropped
fragments still need to be counted on the driver side to avoid page
fragment reference counting issues.
The issue was discovered by the drivers/net/xdp.py selftest,
more specifically the test_xdp_native_tx_mb:
- The mlx5 driver allocates a page_pool page and initializes it with
a frag counter of 64 (pp_ref_count=64) and the internal frag counter
to 0.
- The test sends one packet with no payload.
- On RX (mlx5e_skb_from_cqe_mpwrq_nonlinear()), mlx5 configures the XDP
buffer with the packet data starting in the first fragment which is the
page mentioned above.
- The XDP program runs and calls bpf_xdp_pull_data() which moves the
header into the linear part of the XDP buffer. As the packet doesn't
contain more data, the program drops the tail fragment since it no
longer contains any payload (pp_ref_count=63).
- mlx5 device skips counting this fragment. Internal frag counter
remains 0.
- mlx5 releases all 64 fragments of the page but page pp_ref_count is
63 => negative reference counting error.
Resulting splat during the test:
WARNING: CPU: 0 PID: 188225 at ./include/net/page_pool/helpers.h:297 mlx5e_page_release_fragmented.isra.0+0xbd/0xe0 [mlx5_core]
Modules linked in: [...]
CPU: 0 UID: 0 PID: 188225 Comm: ip Not tainted 6.18.0-rc7_for_upstream_min_debug_2025_12_08_11_44 #1 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:mlx5e_page_release_fragmented.isra.0+0xbd/0xe0 [mlx5_core]
[...]
Call Trace:
<TASK>
mlx5e_free_rx_mpwqe+0x20a/0x250 [mlx5_core]
mlx5e_dealloc_rx_mpwqe+0x37/0xb0 [mlx5_core]
mlx5e_free_rx_descs+0x11a/0x170 [mlx5_core]
mlx5e_close_rq+0x78/0xa0 [mlx5_core]
mlx5e_close_queues+0x46/0x2a0 [mlx5_core]
mlx5e_close_channel+0x24/0x90 [mlx5_core]
mlx5e_close_channels+0x5d/0xf0 [mlx5_core]
mlx5e_safe_switch_params+0x2ec/0x380 [mlx5_core]
mlx5e_change_mtu+0x11d/0x490 [mlx5_core]
mlx5e_change_nic_mtu+0x19/0x30 [mlx5_core]
netif_set_mtu_ext+0xfc/0x240
do_setlink.isra.0+0x226/0x1100
rtnl_newlink+0x7a9/0xba0
rtnetlink_rcv_msg+0x220/0x3c0
netlink_rcv_skb+0x4b/0xf0
netlink_unicast+0x255/0x380
netlink_sendmsg+0x1f3/0x420
__sock_sendmsg+0x38/0x60
____sys_sendmsg+0x1e8/0x240
___sys_sendmsg+0x7c/0xb0
[...]
__sys_sendmsg+0x5f/0xb0
do_syscall_64+0x55/0xc70
The problem applies for XDP_PASS as well which is handled in a different
code path in the driver.
This patch fixes the issue by doing page frag counting on all the
original XDP buffer fragments for all relevant XDP actions (XDP_TX ,
XDP_REDIRECT and XDP_PASS). This is basically reverting to the original
counting before the commit in the fixes tag.
As frag_page is still pointing to the original tail, the nr_frags
parameter to xdp_update_skb_frags_info() needs to be calculated
in a different way to reflect the new nr_frags. |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: RX, Fix XDP multi-buf frag counting for legacy RQ
XDP multi-buf programs can modify the layout of the XDP buffer when the
program calls bpf_xdp_pull_data() or bpf_xdp_adjust_tail(). The
referenced commit in the fixes tag corrected the assumption in the mlx5
driver that the XDP buffer layout doesn't change during a program
execution. However, this fix introduced another issue: the dropped
fragments still need to be counted on the driver side to avoid page
fragment reference counting issues.
Such issue can be observed with the
test_xdp_native_adjst_tail_shrnk_data selftest when using a payload of
3600 and shrinking by 256 bytes (an upcoming selftest patch): the last
fragment gets released by the XDP code but doesn't get tracked by the
driver. This results in a negative pp_ref_count during page release and
the following splat:
WARNING: include/net/page_pool/helpers.h:297 at mlx5e_page_release_fragmented.isra.0+0x4a/0x50 [mlx5_core], CPU#12: ip/3137
Modules linked in: [...]
CPU: 12 UID: 0 PID: 3137 Comm: ip Not tainted 6.19.0-rc3+ #12 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
RIP: 0010:mlx5e_page_release_fragmented.isra.0+0x4a/0x50 [mlx5_core]
[...]
Call Trace:
<TASK>
mlx5e_dealloc_rx_wqe+0xcb/0x1a0 [mlx5_core]
mlx5e_free_rx_descs+0x7f/0x110 [mlx5_core]
mlx5e_close_rq+0x50/0x60 [mlx5_core]
mlx5e_close_queues+0x36/0x2c0 [mlx5_core]
mlx5e_close_channel+0x1c/0x50 [mlx5_core]
mlx5e_close_channels+0x45/0x80 [mlx5_core]
mlx5e_safe_switch_params+0x1a5/0x230 [mlx5_core]
mlx5e_change_mtu+0xf3/0x2f0 [mlx5_core]
netif_set_mtu_ext+0xf1/0x230
do_setlink.isra.0+0x219/0x1180
rtnl_newlink+0x79f/0xb60
rtnetlink_rcv_msg+0x213/0x3a0
netlink_rcv_skb+0x48/0xf0
netlink_unicast+0x24a/0x350
netlink_sendmsg+0x1ee/0x410
__sock_sendmsg+0x38/0x60
____sys_sendmsg+0x232/0x280
___sys_sendmsg+0x78/0xb0
__sys_sendmsg+0x5f/0xb0
[...]
do_syscall_64+0x57/0xc50
This patch fixes the issue by doing page frag counting on all the
original XDP buffer fragments for all relevant XDP actions (XDP_TX ,
XDP_REDIRECT and XDP_PASS). This is basically reverting to the original
counting before the commit in the fixes tag.
As frag_page is still pointing to the original tail, the nr_frags
parameter to xdp_update_skb_frags_info() needs to be calculated
in a different way to reflect the new nr_frags. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_sync: hold conn in hci_connect_acl/le_sync() callbacks
There is theoretical UAF if the conn is freed while the hci_sync task
is running.
Hold refcount to avoid that. |
| In the Linux kernel, the following vulnerability has been resolved:
mmc: vub300: fix use-after-free on disconnect
The vub300 driver maintains an explicit reference count for the
controller and its driver data and the last reference can in theory be
dropped after the driver has been unbound.
This specifically means that the controller allocation must not be
device managed as that can lead to use-after-free.
Note that the lifetime is currently also incorrectly tied the parent USB
device rather than interface, which can lead to memory leaks if the
driver is unbound without its device being physically disconnected (e.g.
on probe deferral).
Fix both issues by reverting to non-managed allocation of the controller. |
| In the Linux kernel, the following vulnerability has been resolved:
perf/core: Fix a refcount leak in attach_perf_ctx_data()
The attach_perf_ctx_data() can race on global and !global cases. The
global case is protected by global_ctx_data_rwsem and shares a single
reference count using perf_ctx_data.global field.
But when it races with !global case, it may miss to set the global field
and result in a reference count leak.
CPU1 CPU2
----------------------------------------------------------------
attach_task_ctx_data(.global=1) attach_task_ctx_data(.global=0)
cd1 = alloc_perf_ctx_data(); cd2 = alloc_perf_ctx_data();
// { .global = 0, .refcount = 1 };
try_cmpxchg(); // success,
// task->perf_ctx_data = cd2
try_cmpxhg(); // fail; old = cd2
refcount_inc_not_zero(&old->refcount); // success
// old.refcount = 2
free_perf_ctx_data(cd1);
Then later detach_global_ctx_data() will see the data but it's not
marked as global, so it won't call detach_task_ctx_data(). |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: hold asoc or transport before mod_timer() in timer handlers
Take the association or transport reference before rearming a timer in the
timer handlers.
The existing code calls mod_timer() before taking the reference needed by
the rearmed timer without holding the sock lock. This creates a race with
timer cleanup: if the timer is deleted after mod_timer() returns but before
the reference is taken, the cleanup path can drop the timer's reference and
destroy the transport or association. The timer handler then takes a
reference on the already freed object and eventually drops it, causing a
refcount underflow.
Hold the object before mod_timer() and drop the reference if mod_timer()
reports that the timer was already pending in timer handlers. Apply the
same ordering to the proto-unreachable path, which can rearm a transport
timer outside the timer handlers without holding the sock lock. |
| In the Linux kernel, the following vulnerability has been resolved:
gpio: zynq: fix runtime PM leak on request error path
pm_runtime_get_sync() leaves the usage counter incremented even when it
fails, and zynq_gpio_request() returns the error without dropping it.
gpiolib does not call ->free() when ->request() fails, so zynq_gpio_free(),
which holds the only matching pm_runtime_put(), never runs. The reference
is leaked and the controller can no longer runtime-suspend, so its clock
stays enabled.
Switch to pm_runtime_resume_and_get(), which only increments the usage
counter on success. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: balance the parent hold in hci_bind_bis()
hci_conn_link() takes a lifetime reference to its parent with
hci_conn_get(), but only takes an operational hold on the child.
hci_conn_unlink() later balances both a hold and a reference on the
parent.
The SCO and CIS paths pass a parent acquired from a connect helper, so
it already has a hold. For an additional BIS, hci_bind_bis() obtains the
parent from hci_conn_hash_lookup_big(), which returns a bare pointer.
Unlinking the child then drops the parent's existing hold and can
schedule it for disconnection while its socket is still using it.
Take a hold on the parent before linking it and drop that hold if linking
fails. A successful link transfers the hold to hci_conn_unlink(). |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_conn: fix CIS hold ownership on reuse
Commit 69997d50ec57 ("Bluetooth: ISO: handle bound CIS cleanup via
hci_conn") made hci_bind_cis() and hci_connect_cis() return a
connection with one hold for the ISO layer. hci_bind_cis() currently
takes that hold only after configuring a CIS, so its BT_CONNECTED and
matching BT_BOUND paths return a bare lookup result. Its configuration
failure path can likewise call hci_conn_drop() before taking a hold.
Take the hold before any state-dependent return or configuration error
so every successful return follows the documented ownership contract
and every error drop is balanced.
hci_connect_cis() also assumes hci_conn_link() always takes a new CIS
hold before dropping the one returned by hci_bind_cis(). However, the
helper returns an existing link without taking another hold. In that
case, preserve the CIS hold for the caller and drop the redundant LE
hold because the existing link already owns its parent hold. Returning
early also avoids changing an existing CIS back to BT_CONNECT. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/nouveau: Fix gem reference leak in validate_init()
On the ttm_bo_reserve() failure and "vma not found" error paths, the
loop breaks without adding the looked-up object to any validate list,
so the reference taken by drm_gem_object_lookup() is never released;
validate_fini() only walks the spliced lists. Drop the reference
before breaking out on both paths. |
| In the Linux kernel, the following vulnerability has been resolved:
gpio: arizona: Fix runtime PM leak in arizona_gpio_direction_out()
Switching a persistent GPIO line from input to output acquires a
runtime PM reference on the parent device, but if the subsequent
regmap_update_bits() fails the reference is never dropped and no later
direction_in() can balance it since the direction was never changed.
Drop the reference on the update failure path. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: release unused CIS holds after channel attach
hci_bind_cis() and hci_connect_cis() return one hci_conn hold for the
ISO layer. A new channel association consumes that hold, which is
eventually released by iso_conn_free().
There are two cases where iso_chan_add() does not create an association:
it returns success when the socket is already attached to the same
iso_conn, and it returns -EBUSY when another socket is attached. The
hold returned for the current call is unused in both cases. This occurs
when deferred setup calls iso_connect_cis() again for its existing
socket, or when another socket attempts to reuse the CIS.
Detect the idempotent case while the connection is locked and release
the unused hold after iso_chan_add(). Also release it on -EBUSY. Do not
drop it for other errors: a newly allocated iso_conn releases the
transferred hold when its last temporary reference is put. |
| In the Linux kernel, the following vulnerability has been resolved:
dm: avoid leaking the caller's thread keyring via the table device file
The refactoring in commit a28d893eb327 ("md: port block device access to file")
accidentally causes the caller's thread keyring to be kept alive long
beyond the caller's lifetime.
As a result, "cryptsetup luksSuspend" silently fails to wipe the
LUKS volume key from memory.
In detail: "cryptsetup luksOpen" uses its supposedly ephemeral thread
keyring to pass the volume key to the kernel. dm-crypt's
crypt_set_keyring_key() copies the key material into its own
crypt_config structure and then drops its own reference to the key in
the keyring with key_put().
With this fix, restoring pre-v6.9 behavior, the copy in the thread
keyring is then promptly garbage collected, such that exactly one copy
of the volume key remains. This single copy is correctly wiped from
memory on "cryptsetup luksSuspend".
Without this fix, the thread keyring and the volume key in it remains.
This second copy is only freed on "luksClose". "luksSuspend" neither
knows about this copy nor has any way to remove it, so the key remains
recoverable from RAM after a suspend that is documented to have wiped it.
This fix should not introduce new security problems, as the code is
anyway gated by CAP_SYS_ADMIN. The device-mapper core, not the calling
task, is the legitimate owner of this long-lived file. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: xen: scsiback: Free unsubmitted command instead of double-putting it
scsiback_get_pend_req() obtains a command tag and returns a vscsibk_pend
whose embedded se_cmd has only been memset to 0, so its cmd_kref is 0;
the se_cmd is initialised (kref_init() via target_init_cmd()) only
later, in scsiback_cmd_exec(), on the successful VSCSIIF_ACT_SCSI_CDB
path. The two error paths in scsiback_do_cmd_fn() taken before the
command is submitted -- a failed scsiback_gnttab_data_map() and an
unknown ring_req.act -- call
transport_generic_free_cmd(&pending_req->se_cmd, 0), which kref_put()s a
refcount of 0. That underflows it ("refcount_t: underflow;
use-after-free") and, as the release function is not run, leaks the
command tag.
Impact: a pvSCSI guest can leak every command tag of a LUN's session,
stopping the LUN, by submitting requests with a bad grant reference or
an unknown request type; under panic_on_warn the refcount underflow
panics the host.
Add a helper that just returns the tag with target_free_tag() and sends
the error response. It frees the tag while the v2p reference still pins
the session, and snapshots the response fields beforehand because
freeing the tag can let another ring reuse the pending_req slot. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: mgmt: hold reference for hci_conn in mgmt_pending_cmds
Dereferencing RCU-protected pointers outside critical sections is
invalid and may lead to UAF. Use of hci_conn in hci_sync callbacks also
needs to hold refcount to avoid UAF.
Take appropriate locks for hci_conn lookups, and take refcount for
hci_conn pointers stored in mgmt_pending_cmd so that the pointer stays
valid.
When accessing conn->state, ensure hdev->lock is held to avoid data
race. |
| In the Linux kernel, the following vulnerability has been resolved:
nvmet-tcp: check INIT_FAILED before nvmet_req_uninit in digest error path
In nvmet_tcp_try_recv_ddgst(), when a data digest mismatch is detected,
nvmet_req_uninit() is called unconditionally. However, if the command
arrived via the nvmet_tcp_handle_req_failure() path, nvmet_req_init()
had returned false and percpu_ref_tryget_live() was never executed. The
unconditional percpu_ref_put() inside nvmet_req_uninit() then causes a
refcount underflow, leading to a WARNING in
percpu_ref_switch_to_atomic_rcu, a use-after-free diagnostic, and
eventually a permanent workqueue deadlock.
Check cmd->flags & NVMET_TCP_F_INIT_FAILED before calling
nvmet_req_uninit(), matching the existing pattern in
nvmet_tcp_execute_request(). |
| In the Linux kernel, the following vulnerability has been resolved:
ceph: put folios not suitable for writeback
The batch holds references to the folios (see `filemap_get_folios`,
`folio_batch_release`), so we need to `folio_put` the folios we remove.
Tested on v6.18. |
| In the Linux kernel, the following vulnerability has been resolved:
net: qrtr: fix refcount saturation and potential UAF in qrtr_port_remove
In qrtr_port_remove(), the socket reference count is decremented via
__sock_put() before the port is removed from the qrtr_ports XArray and
before the RCU grace period elapses.
This breaks the fundamental RCU update paradigm. It exposes a race
window where a concurrent RCU reader (such as qrtr_reset_ports() or
qrtr_port_lookup()) can obtain a pointer to the socket from the XArray,
and attempt to call sock_hold() on a socket whose reference count has
already dropped to zero.
This exact race condition was hit during syzkaller fuzzing, leading to
the following refcount saturation warning and a potential Use-After-Free:
refcount_t: saturated; leaking memory.
WARNING: CPU: 3 PID: 1273 at lib/refcount.c:22 refcount_warn_saturate+0xae/0x1d0
Modules linked in: qrtr(+) bochs drm_shmem_helper ...
Call Trace:
<TASK>
qrtr_reset_ports net/qrtr/af_qrtr.c:768 [inline] [qrtr]
__qrtr_bind.isra.0+0x48b/0x570 net/qrtr/af_qrtr.c:805 [qrtr]
qrtr_bind+0x17d/0x210 net/qrtr/af_qrtr.c:901 [qrtr]
kernel_bind+0xe4/0x120 net/socket.c:3592
qrtr_ns_init+0x1a6/0x380 net/qrtr/ns.c:715 [qrtr]
qrtr_proto_init+0x3b/0xff0 net/qrtr/af_qrtr.c:169 [qrtr]
do_one_initcall+0xf5/0x5e0 init/main.c:1283
...
</TASK>
Fix this by deferring the reference count decrement until after the
xa_erase() and the synchronize_rcu() complete.
(Note: The v1 of this patch incorrectly replaced __sock_put() with
sock_put(). As Simon Horman pointed out, the callers of qrtr_port_remove()
still hold a reference to the socket, so freeing the socket memory here
would lead to a subsequent UAF in the caller. Thus, the __sock_put() is
kept, but only repositioned to close the RCU race.) |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: vgic-its: Drop the translation cache reference only for the erased entry
vgic_its_invalidate_cache() walks the per-ITS translation cache with
xa_for_each() and drops the cache's reference on each entry with
vgic_put_irq(). It puts the iterated pointer, though, rather than the
value returned by xa_erase().
The function is called from contexts that do not exclude one another: the
ITS command handlers hold its_lock, the GITS_CTLR write path holds
cmd_lock, and the path that clears EnableLPIs in a redistributor's
GICR_CTLR holds neither. Two or more of them can drain the same cache
concurrently, and if each one observes the same entry, erases it and then
puts it, the single reference the cache holds on that entry is dropped
more than once. The entry can then be freed while an ITE still maps it.
xa_erase() is atomic and returns the previous entry, so put only the entry
that this context actually removed. The cache reference is then dropped
exactly once per entry even when the invalidations run concurrently, and
the behavior is unchanged when only one context runs. |
