net/smc: fix qentry overwrite for CONFIRM_LINK and ADD_LINK_CONT in smc_llc_event_handler()
In the Linux kernel, the following vulnerability has been resolved:
net/smc: fix qentry overwrite for CONFIRM_LINK and ADD_LINK_CONT in smc_llc_event_handler()
The SMC_LLC_CONFIRM_LINK / SMC_LLC_ADD_LINK_CONT branch in
smc_llc_event_handler() stores an incoming qentry into the local LLC flow
without first checking whether a qentry is already pending. If a malicious or
buggy peer sends a second CONFIRM_LINK or ADD_LINK_CONT request while a flow is
active and flow->qentry is already set, smc_llc_flow_qentry_set() overwrites the
pointer without freeing the previous allocation, leaking one kmalloc-96 object
per spurious message.
The sibling SM
devlink: fix net namespace reference leak in reload
In the Linux kernel, the following vulnerability has been resolved:
devlink: fix net namespace reference leak in reload
devlink_nl_reload_doit() calls devlink_netns_get(), which returns a net
with a held reference. When the requested namespace differs from the
current one and the reload action is not DRIVER_REINIT, the function
returns -EOPNOTSUPP without releasing the reference. Add the missing
put_net() on this error path.
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: fw_tracer, return NULL on create error
Tracer creation can fail by returning either NULL or ERR_PTR.
The return value is stored without a check on the device, and users
treat ERR_PTR and NULL the same way.
This also causes a crash in the core dump logic, which is missing the
ERR_PTR check and ends up dereferencing it, as shown in the trace below.
Switch tracer creation to return NULL on failure only, so callers only
need a single NULL check.
Internal error: Oops: 0000000096000006 [#1] SMP
Modules linked in: mlx5_ib ib_uverbs ib_core ipv6 mlx5_core
CPU: 1
accel/amdxdna: Fix locally exploitable BUG_ON in amdxdna_insert_pages()
In the Linux kernel, the following vulnerability has been resolved:
accel/amdxdna: Fix locally exploitable BUG_ON in amdxdna_insert_pages()
In amdxdna_insert_pages(), vm_flags_mod() sets VM_MIXEDMAP and clears
VM_PFNMAP. If an unprivileged userspace process mmaps a non-imported GEM
object and then calls madvise(MADV_DONTNEED), the PTEs will be
successfully cleared because VM_MIXEDMAP allows this (unlike VM_PFNMAP).
When userspace subsequently accesses the memory, drm_gem_shmem_fault()
handles the page fault and attempts to map the backing shmem page via
vmf_insert_pfn() which calls vmf_insert_pfn_prot(). Because the backing
shmem page is n
bpf: Fix netns reference imbalance in conntrack kfuncs
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix netns reference imbalance in conntrack kfuncs
The opts argument of the BPF conntrack kfuncs can point to a shared
map value. __bpf_nf_ct_lookup() and __bpf_nf_ct_alloc_entry() read
opts->netns_id separately when acquiring and releasing the network
namespace reference.
The reference imbalance can occur as follows:
CPU 0 CPU 1
read opts->netns_id (-1)
skip get_net_ns_by_id()
write opts->netns_id (id)
read opts->netns_id (id)
put_net(net) /* no matching get */
The reverse transitio
bpf: tcp: Fix use-after-free in bpf_iter_tcp_established_batch()
In the Linux kernel, the following vulnerability has been resolved:
bpf: tcp: Fix use-after-free in bpf_iter_tcp_established_batch()
reqsk_queue_hash_req() publishes a TCP_NEW_SYN_RECV request_sock onto
the ehash chain, drops the bucket lock, and only afterwards sets
rsk_refcnt to 3.
Lockless readers such as __inet_lookup_established() handle this with
refcount_inc_not_zero(), but bpf_iter_tcp_established_batch() uses plain
sock_hold() while holding the bucket lock, on the assumption that the
lock guarantees sk_refcnt > 0. That assumption does not hold for
request_sock:
CPU 0 CPU 1
-----
In the Linux kernel, the following vulnerability has been resolved:
vhost_iotlb: bound map allocation in add_range
vhost_iotlb_add_range_ctx() only retires an old entry when the table
has a non-zero limit, has exactly reached that limit and has
VHOST_IOTLB_FLAG_RETIRE set. Non-retiring tables can keep allocating
entries after reaching their configured limit.
Existing vhost devices allocate their IOTLB with max_iotlb_entries from
vhost.c, which defaults to 2048 and is tunable by module parameter. Use
the caller-provided limit at the allocation point instead of adding a
separate default in the common IOTLB helper, and reject non-positive
val
vdpa/mlx5: Fix buffer length in create_direct_keys()
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 reg
hwmon: (pmbus) Fix type confusion in notification logic
In the Linux kernel, the following vulnerability has been resolved:
hwmon: (pmbus) Fix type confusion in notification logic
Sashiko reports:
At the start of the loop in pmbus_notify(), the code unconditionally casts
every attribute to a struct sensor_device_attribute:
drivers/hwmon/pmbus/pmbus_core.c:pmbus_notify() {
for (i = 0; i < data->num_attributes; i++) {
struct device_attribute *da = to_dev_attr(data->group.attrs[i]);
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
int index = attr->index;
...
}
However, data->group.attrs can contain other types like struct
pmbus_samples_reg or struct pmb
In the Linux kernel, the following vulnerability has been resolved:
xsk: require at least 16 bytes of TX metadata
AF_XDP accepts a TX metadata length as small as eight bytes, but every
supported request needs the flags plus at least one eight-byte request
field. Such short metadata also lets the kernel read beyond the registered
area.
Require 16 bytes rather than sizeof(struct xsk_tx_metadata) to preserve
compatibility with applications that do not use launch-time metadata.
xsk: clear metadata pointer when no timestamp is requested
In the Linux kernel, the following vulnerability has been resolved:
xsk: clear metadata pointer when no timestamp is requested
User space can change metadata flags after request processing. Rereading
them during completion can therefore make the kernel write a timestamp
that was not requested when the packet was submitted.
Clear the metadata pointer during request processing unless timestamp
completion is requested. Completion handling can then use the pointer
itself instead of rereading the flags.
On the mlx5 multi-packet WQE path metadata is evaluated per batch:
xsk_tx_metadata_request() runs only for the descriptor that starts a
sessio
In the Linux kernel, the following vulnerability has been resolved:
xsk: validate launch-time metadata size
Launch-time metadata extends beyond the first 16 bytes of struct
xsk_tx_metadata. Reject the request when the registered metadata area does
not contain the complete field.
Snapshot the validated flags for the generic transmit path and use that
snapshot for request and completion processing, avoiding inconsistent
decisions if user space changes the flags concurrently.
Note that only xsk_skb_metadata is properly using the flags,
__xsk_buff_get_metadata ignores them. Next commits address that.
In the Linux kernel, the following vulnerability has been resolved:
xsk: validate metadata when processing requests
The zero-copy path validates TX metadata while obtaining the descriptor
context, then reads it again later when preparing the hardware request.
User space can change the metadata between those operations and bypass the
original validation.
Validate the metadata in xsk_tx_metadata_request() and use the resulting
flags snapshot for every feature check. Read request fields once so all
zero-copy drivers process only values observed after successful
validation.
bnge: Fix NULL pointer dereference in aux device release
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 allo
udp: fix potential use-after-free in tunnel segmentation
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.
net/sched: sch_cake: drop WARN_ON(1) for malformed packets in ACK filter
In the Linux kernel, the following vulnerability has been resolved:
net/sched: sch_cake: drop WARN_ON(1) for malformed packets in ACK filter
The sch_cake ACK filter parses packets to find the TCP header and filter
duplicated ACKs if the flow is backlogged. The parsing code contains a
WARN_ON(1) which can be triggered by a malformed IP header in certain
cases. Depending on the system configuration, this leads either to
either spamming dmesg with warnings, or a panic if panic_on_warn is set.
The code already correctly skips the offending packet in the branch that
triggers the warning, so the WARN_ON itself doesn't really serve any
purpose. S
In the Linux kernel, the following vulnerability has been resolved:
vhost-scsi: Validate T10 PI scatterlist counts
When T10 PI is negotiated, vhost-scsi splits protection bytes from
the data iterator before mapping the request scatterlists. A malformed
request can claim protection bytes that cover or exceed the full payload
length. The former leaves no data bytes to map, while the latter
underflows exp_data_len before advancing the iterator. Both cases can let
a zero data SGL count reach sg_alloc_table_chained(), which triggers
BUG_ON(!nents).
Reject protection lengths that cover or exceed the payload before
subtracting prot_bytes and adva
In the Linux kernel, the following vulnerability has been resolved:
vhost-scsi: reject feature changes after endpoint
vhost_scsi_setup_vq_cmds() runs from VHOST_SCSI_SET_ENDPOINT and allocates
each command's protection scatterlist array (prot_sgl) according to the
acknowledged VIRTIO_SCSI_F_T10_PI bit. The command pools are not rebuilt
when VHOST_SET_FEATURES changes that bit later.
Although virtio feature bits must not change after feature negotiation,
vhost_scsi_set_features() currently accepts such a request after the
endpoint is active and updates acked_features. Enabling T10-PI after
endpoint setup therefore leaves prot_sgl NULL whi
net/openvswitch: check Ethernet header length in key_extract()
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/
net/sched: cls_api: Always acquire rtnl_lock when destroying locked classifiers
In the Linux kernel, the following vulnerability has been resolved:
net/sched: cls_api: Always acquire rtnl_lock when destroying locked classifiers
Another challenge with unlocked filters.
There is a short window in tc_new_tfilter where a tcf_proto can be found
and briefly referenced by a totally unrelated, unlocked classifier's request
and cause a race.
Feng created a poc which created this race with two threads, one creating a
u32 filter and other a flower filter in the same chain/prio:
1. Both threads enter tc_new_tfilter, both find the chain empty, both
drop filter_chain_lock
2. u32 finishes tcf_proto_create("u32") first, calls