| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: sit: reload inner IPv6 header after GSO offloads
ipip6_tunnel_xmit() caches the inner IPv6 header pointer at function
entry and continues using it after iptunnel_handle_offloads().
For GSO skbs, iptunnel_handle_offloads() calls skb_header_unclone().
When the skb header is cloned, skb_header_unclone() can call
pskb_expand_head(), which may move the skb head. The pskb_expand_head()
contract requires pointers into the skb header to be reloaded after the
call.
If the later skb_realloc_headroom() branch is not taken, SIT uses the
stale iph6 pointer to read the inner hop limit and DS field. That can
read from a freed skb head after the old head's remaining clone is
released.
Reload iph6 after the offload helper succeeds and before subsequent
reads from the inner IPv6 header. Keep the existing reload after
skb_realloc_headroom(), since that branch can also replace the skb. |
| In the Linux kernel, the following vulnerability has been resolved:
net: guard timestamp cmsgs to real error queue skbs
skb_is_err_queue() treats PACKET_OUTGOING as the sole marker for an skb
from sk_error_queue. That assumption is not true for AF_PACKET sockets:
outgoing packet taps are also delivered to packet sockets with
skb->pkt_type == PACKET_OUTGOING, but their skb->cb is owned by AF_PACKET
instead of struct sock_exterr_skb.
If such an skb is received with timestamping enabled, the generic
timestamp cmsg path can read AF_PACKET control-buffer state as
sock_exterr_skb::opt_stats. With SO_RXQ_OVFL enabled, the packet drop
counter overlaps opt_stats. An odd drop count makes the path emit
SCM_TIMESTAMPING_OPT_STATS with skb->len and skb->data. For non-linear
skbs this copies past the linear head and can trigger hardened usercopy or
disclose adjacent heap contents.
Keep skb_is_err_queue() local to net/socket.c, but make it verify that
the PACKET_OUTGOING marker is paired with the sock_rmem_free destructor
installed by sock_queue_err_skb(). AF_PACKET receive skbs use normal
receive ownership and no longer pass as error-queue skbs, while legitimate
sk_error_queue entries keep the PACKET_OUTGOING marker and sock_rmem_free
ownership. |
| In the Linux kernel, the following vulnerability has been resolved:
ip6_vti: fix incorrect tunnel matching in vti6_tnl_lookup()
In vti6_tnl_lookup(), when an exact match for a tunnel fails,
the code falls back to searching for wildcard tunnels:
- Tunnels matching the packet's local address, with any remote address
wildcard remote).
- Tunnels matching the packet's remote address, with any local address
(wildcard local).
However, vti6 stores all these different types of tunnels in the same
hash table (ip6n->tnls_r_l) prone to hash collisions.
The bug is that the fallback search loops in vti6_tnl_lookup() were
missing checks to ensure that the candidate tunnel actually has
a wildcard address. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: x_tables: avoid leaking percpu counter pointers
The native and compat get-entries paths copy the fixed rule entry header
from the kernelized rule blob to userspace before overwriting the entry's
counter fields with a sanitized counter snapshot.
On SMP kernels, entry->counters.pcnt contains the percpu allocation
address used by x_tables rule counters. A caller can provide a userspace
buffer that faults during the initial fixed-header copy after pcnt has
been copied but before the later sanitized counter copy runs. The syscall
then returns -EFAULT while leaving the raw percpu pointer in userspace.
Copy only the fixed entry prefix before counters from the kernelized rule
blob, then copy the sanitized counter snapshot into the counter field.
Apply this ordering to the IPv4, IPv6, and ARP native and compat
get-entries implementations so a fault cannot expose the internal percpu
counter pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: reject BR/EDR signaling packets over MTUsig
net/bluetooth/l2cap_core.c:l2cap_sig_channel() accepts BR/EDR
signaling packets up to the channel MTU and dispatches each command
without enforcing the signaling MTU (MTUsig). A Bluetooth BR/EDR peer
within radio range can send a fixed-channel CID 0x0001 packet that is
larger than MTUsig and contains many L2CAP_ECHO_REQ commands before
pairing. In a real-radio stock-kernel run, one 681-byte signaling
packet containing 168 zero-length ECHO_REQ commands made the target
transmit 168 ECHO_RSP frames over about 220 ms.
Impact: a Bluetooth BR/EDR peer within radio range, before pairing, can
force 168 ECHO_RSP frames from one 681-byte fixed-channel signaling
packet containing packed ECHO_REQ commands.
Define Linux's BR/EDR signaling MTU as the spec minimum of 48 bytes and
reject any larger signaling packet with one L2CAP_COMMAND_REJECT_RSP
carrying L2CAP_REJ_MTU_EXCEEDED before any command is dispatched.
The Bluetooth Core spec wording for MTUExceeded says the reject
identifier shall match the first request command in the packet, and
that packets containing only responses shall be silently discarded.
Linux intentionally deviates from that prescription: silently
discarding desynchronizes the peer because the remote stack never
learns its responses were dropped, and locating the first request
command requires walking command headers past MTUsig, i.e. processing
bytes from a packet we have already decided is too large to process.
We therefore always emit one reject and use the identifier from the
first command header, a single fixed-offset byte read.
The unrestricted BR/EDR signaling parser and ECHO_REQ response path both
trace to the initial git import; no later introducing commit is
available for a Fixes tag. |
| In the Linux kernel, the following vulnerability has been resolved:
udp: clear skb->dev before running a sockmap verdict
On the UDP receive path skb->dev is repurposed as dev_scratch (the
truesize/state cache set by udp_set_dev_scratch()), through the
union { struct net_device *dev; unsigned long dev_scratch; } in sk_buff.
When a UDP socket is in a sockmap, sk_data_ready is
sk_psock_verdict_data_ready(), which calls udp_read_skb() -> recv_actor()
(sk_psock_verdict_recv) to run the attached SK_SKB verdict program in softirq.
If that program calls a socket-lookup helper (bpf_sk_lookup_tcp/udp,
bpf_skc_lookup_tcp), bpf_skc_lookup() does:
if (skb->dev)
caller_net = dev_net(skb->dev);
skb->dev still holds the dev_scratch value (a non-NULL integer), so dev_net()
dereferences it as a struct net_device * and the kernel takes a general
protection fault on a non-canonical address in softirq:
Oops: general protection fault, probably for non-canonical address 0x1010000800004a0
CPU: 1 UID: 0 PID: 1406 Comm: syz.2.19 Not tainted 7.1.0-rc6 #1 PREEMPT(full)
RIP: 0010:bpf_skc_lookup net/core/filter.c:7033 [inline]
RIP: 0010:bpf_sk_lookup+0x45/0x160 net/core/filter.c:7047
Call Trace:
<IRQ>
bpf_prog_4675cb904b7071f8+0x12e/0x14e
bpf_prog_run_pin_on_cpu+0xc6/0x1f0
sk_psock_verdict_recv+0x1ba/0x350
udp_read_skb+0x31a/0x370
sk_psock_verdict_data_ready+0x2e3/0x600
__udp_enqueue_schedule_skb+0x4c8/0x650
udpv6_queue_rcv_one_skb+0x3ec/0x740
udp6_unicast_rcv_skb+0x11d/0x140
ip6_protocol_deliver_rcu+0x61e/0x950
ip6_input_finish+0xa9/0x150
NF_HOOK+0x286/0x2f0
ip6_input+0x117/0x220
NF_HOOK+0x286/0x2f0
__netif_receive_skb+0x85/0x200
process_backlog+0x374/0x9a0
__napi_poll+0x4f/0x1c0
net_rx_action+0x3b0/0x770
handle_softirqs+0x15a/0x460
do_softirq+0x57/0x80
</IRQ>
The rmem charge that dev_scratch accounted for is released by skb_recv_udp() on
dequeue, just above, so the scratch is dead by the time recv_actor() runs. Clear
skb->dev so bpf_skc_lookup() falls back to sock_net(skb->sk), which
skb_set_owner_sk_safe() set just above. |
| In the Linux kernel, the following vulnerability has been resolved:
mptcp: allow subflow rcv wnd to shrink
In MPTCP connection, the `window` field in the TCP header refers to the
MPTCP-level rcv_nxt and it's right edge should not move backward. Such
constraint is enforced at DSS option generation time.
At the same time, the TCP stack ensures independently that the TCP-level
rcv wnd right's edge does not move backward. That in turn causes artificial
inflating of the MPTCP rcv window when the incoming data is acked at the
TCP level and is OoO in the MPTCP sequence space (or lands in the backlog).
As a consequence, the incoming traffic can exceed the receiver rcvbuf size
even when the sender is not misbehaving.
Prevent such scenario forcibly allowing the TCP subflow to shrink the
TCP-level rcv wnd regardless of the current netns setting. |
| In the Linux kernel, the following vulnerability has been resolved:
fuse: reject fuse_notify() pagecache ops on directories
The operations FUSE_NOTIFY_STORE and FUSE_NOTIFY_RETRIEVE allow the
FUSE daemon to actively write/read pagecache contents.
For directories with FOPEN_CACHE_DIR, the pagecache is used as
kernel-internal cache storage, and userspace is not supposed to have
direct access to this cache - in particular, fuse_parse_cache() will hit
WARN_ON() if the cache contains bogus data.
Reject FUSE_NOTIFY_STORE and FUSE_NOTIFY_RETRIEVE on anything other than
regular files with -EINVAL. |
| In the Linux kernel, the following vulnerability has been resolved:
thunderbolt: Limit XDomain response copy to actual frame size
tb_xdomain_copy() copies req->response_size bytes from the received
packet buffer regardless of the actual frame size. When a short
response arrives, this reads past the valid frame data in the DMA
pool buffer into stale contents from previous transactions.
Use the minimum of frame size and expected response size for the
copy length. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: require Ethernet MAC header before using eth_hdr()
`ip6t_eui64`, `xt_mac`, the `bitmap:ip,mac`, `hash:ip,mac`, and
`hash:mac` ipset types, and `nf_log_syslog` access `eth_hdr(skb)`
after either assuming that the skb is associated with an Ethernet
device or checking only that the `ETH_HLEN` bytes at
`skb_mac_header(skb)` lie between `skb->head` and `skb->data`.
Make these paths first verify that the skb is associated with an
Ethernet device, that the MAC header was set, and that it spans at
least a full Ethernet header before accessing `eth_hdr(skb)`. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: xtables: restrict several matches to inet family
This is a partial revert of:
commit ab4f21e6fb1c ("netfilter: xtables: use NFPROTO_UNSPEC in more extensions")
to allow ipv4 and ipv6 only.
- xt_mac
- xt_owner
- xt_physdev
These extensions are not used by ebtables in userspace.
Moreover, xt_realm is only for ipv4, since dst->tclassid is ipv4
specific. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_ct: fix missing expect put in obj eval
nft_ct_expect_obj_eval() allocates an expectation and may call
nf_ct_expect_related(), but never drops its local reference.
Add nf_ct_expect_put(exp) before return to balance allocation. |
| In the Linux kernel, the following vulnerability has been resolved:
ipc/shm: serialize orphan cleanup with shm_nattch updates
shm_destroy_orphaned() walks the shm idr under shm_ids(ns).rwsem, but that
does not serialize all fields tested by shm_may_destroy(). In particular,
shm_nattch is updated while holding shm_perm.lock, and attach paths can do
that without holding the rwsem.
Do not decide that an orphaned segment is unused before taking the object
lock. Move the shm_may_destroy() check under shm_perm.lock, matching the
other destroy paths, and unlock the segment when it no longer qualifies
for removal. |
| In the Linux kernel, the following vulnerability has been resolved:
af_unix: Reject SIOCATMARK on non-stream sockets
SIOCATMARK reports whether the receive queue is at the urgent mark for
MSG_OOB.
In AF_UNIX, MSG_OOB is supported only for SOCK_STREAM sockets.
SOCK_DGRAM and SOCK_SEQPACKET reject MSG_OOB in sendmsg() and recvmsg(),
so they should not support SIOCATMARK either.
Return -EOPNOTSUPP for non-stream sockets before checking the receive
queue. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: serialize accept_q access
bt_sock_poll() walks the accept queue without synchronization, while
child teardown can unlink the same socket and drop its last reference.
The unsynchronized accept queue walk has existed since the initial
Bluetooth import.
Protect accept_q with a dedicated lock for queue updates and polling.
Also rework bt_accept_dequeue() to take temporary child references under
the queue lock before dropping it and locking the child socket. |
| In the Linux kernel, the following vulnerability has been resolved:
ip6_vti: set netns_immutable on the fallback device.
john1988 and Noam Rathaus reported that vti6_init_net() does not set the
netns_immutable flag on the per-netns fallback tunnel device (ip6_vti0).
Other similar tunnel drivers (like ip6_tunnel, sit, ip6_gre, and ip_tunnel)
correctly set this flag during their fallback device initialization to
prevent them from being moved to another network namespace. |
| In the Linux kernel, the following vulnerability has been resolved:
tun: free page on build_skb failure in tun_xdp_one()
When build_skb() fails in tun_xdp_one(), the function sets ret to
-ENOMEM and jumps to the out label, which returns without freeing the
page that vhost_net_build_xdp() allocated for the frame. As with the
short-frame rejection path, tun_sendmsg() discards the per-buffer error
and still returns total_len, so vhost_tx_batch() takes the success path
and never frees the page. Each build_skb() failure in a batch leaks one
page-frag chunk.
Free the page before taking the error path, matching the put_page() the
other error exits of tun_xdp_one() already perform. |
| In the Linux kernel, the following vulnerability has been resolved:
tun: free page on short-frame rejection in tun_xdp_one()
tun_xdp_one() returns -EINVAL on a frame shorter than ETH_HLEN without
freeing the page that vhost_net_build_xdp() allocated for it.
tun_sendmsg() discards that -EINVAL and still returns total_len, so
vhost_tx_batch() takes the success path and never frees the page; each
short frame in a batch leaks one page-frag chunk.
A local process that can open /dev/net/tun and /dev/vhost-net can hit
this path: it attaches a tun/tap device as the vhost-net backend and
feeds TX descriptors whose length minus the virtio-net header is below
ETH_HLEN. Each kick leaks the page-frag chunks for that batch, and a
tight submission loop exhausts host memory and triggers an OOM panic.
Free the page before returning -EINVAL, matching the XDP-program error
path in the same function. |
| In the Linux kernel, the following vulnerability has been resolved:
tap: free page on error paths in tap_get_user_xdp()
tap_get_user_xdp() rejects a frame shorter than ETH_HLEN with -EINVAL,
and returns -ENOMEM when build_skb() fails. Both paths jump to the err
label without freeing the page that vhost_net_build_xdp() allocated for
the frame. tap_sendmsg() discards the per-buffer return value and always
returns 0, so vhost_tx_batch() takes the success path and never frees
the page; each rejected frame in a batch leaks one page-frag chunk.
Free the page on both error paths, before the skb is built. This is the
tap counterpart of the same leak in tun_xdp_one(). |
| In the Linux kernel, the following vulnerability has been resolved:
flow_dissector: do not dissect PPPoE PFC frames
RFC 2516 Section 7 states that Protocol Field Compression (PFC) is NOT
RECOMMENDED for PPPoE. In practice, pppd does not support negotiating
PFC for PPPoE sessions, and the flow dissector driver has assumed an
uncompressed frame until the blamed commit.
During the review process of that commit [1], support for PFC is
suggested. However, having a compressed (1-byte) protocol field means
the subsequent PPP payload is shifted by one byte, causing 4-byte
misalignment for the network header and an unaligned access exception
on some architectures.
The exception can be reproduced by sending a PPPoE PFC frame to an
ethernet interface of a MIPS board, with RPS enabled, even if no PPPoE
session is active on that interface:
$ 0 : 00000000 80c40000 00000000 85144817
$ 4 : 00000008 00000100 80a75758 81dc9bb8
$ 8 : 00000010 8087ae2c 0000003d 00000000
$12 : 000000e0 00000039 00000000 00000000
$16 : 85043240 80a75758 81dc9bb8 00006488
$20 : 0000002f 00000007 85144810 80a70000
$24 : 81d1bda0 00000000
$28 : 81dc8000 81dc9aa8 00000000 805ead08
Hi : 00009d51
Lo : 2163358a
epc : 805e91f0 __skb_flow_dissect+0x1b0/0x1b50
ra : 805ead08 __skb_get_hash_net+0x74/0x12c
Status: 11000403 KERNEL EXL IE
Cause : 40800010 (ExcCode 04)
BadVA : 85144817
PrId : 0001992f (MIPS 1004Kc)
Call Trace:
[<805e91f0>] __skb_flow_dissect+0x1b0/0x1b50
[<805ead08>] __skb_get_hash_net+0x74/0x12c
[<805ef330>] get_rps_cpu+0x1b8/0x3fc
[<805fca70>] netif_receive_skb_list_internal+0x324/0x364
[<805fd120>] napi_complete_done+0x68/0x2a4
[<8058de5c>] mtk_napi_rx+0x228/0xfec
[<805fd398>] __napi_poll+0x3c/0x1c4
[<805fd754>] napi_threaded_poll_loop+0x234/0x29c
[<805fd848>] napi_threaded_poll+0x8c/0xb0
[<80053544>] kthread+0x104/0x12c
[<80002bd8>] ret_from_kernel_thread+0x14/0x1c
Code: 02d51821 1060045b 00000000 <8c640000> 3084000f 2c820005 144001a2 00042080 8e220000
To reduce the attack surface and maintain performance, do not process
PPPoE PFC frames.
[1] https://lore.kernel.org/r/20220630231016.GA392@debian.home |
