OESA-2026-3702

The Linux Kernel, the operating system core itself.

Security Fix(es):

In the Linux kernel, the following vulnerability has been resolved:

net/9p: fix double req put in p9_fd_cancelled

Syzkaller reports a KASAN issue as below:

general protection fault, probably for non-canonical address 0xfbd59c0000000021: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: maybe wild-memory-access in range [0xdead000000000108-0xdead00000000010f] CPU: 0 PID: 5083 Comm: syz-executor.2 Not tainted 6.1.134-syzkaller-00037-g855bd1d7d838 #0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:__list_del include/linux/list.h:114 [inline] RIP: 0010:__list_del_entry include/linux/list.h:137 [inline] RIP: 0010:list_del include/linux/list.h:148 [inline] RIP: 0010:p9_fd_cancelled+0xe9/0x200 net/9p/trans_fd.c:734

Call Trace: <TASK> p9_client_flush+0x351/0x440 net/9p/client.c:614 p9_client_rpc+0xb6b/0xc70 net/9p/client.c:734 p9_client_version net/9p/client.c:920 [inline] p9_client_create+0xb51/0x1240 net/9p/client.c:1027 v9fs_session_init+0x1f0/0x18f0 fs/9p/v9fs.c:408 v9fs_mount+0xba/0xcb0 fs/9p/vfs_super.c:126 legacy_get_tree+0x108/0x220 fs/fs_context.c:632 vfs_get_tree+0x8e/0x300 fs/super.c:1573 do_new_mount fs/namespace.c:3056 [inline] path_mount+0x6a6/0x1e90 fs/namespace.c:3386 do_mount fs/namespace.c:3399 [inline] __do_sys_mount fs/namespace.c:3607 [inline] __se_sys_mount fs/namespace.c:3584 [inline] __x64_sys_mount+0x283/0x300 fs/namespace.c:3584 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x6e/0xd8

This happens because of a race condition between:

• The 9p client sending an invalid flush request and later cleaning it up;

• The 9p client in p9_read_work() canceled all pending requests.

  Thread 1                              Thread 2
  

  ... p9_client_create() ... p9_fd_create() ... p9_conn_create() ... // start Thread 2 INIT_WORK(&m->rq, p9_read_work); p9_read_work() ... p9_client_rpc() ... ... p9_conn_cancel() ... spin_lock(&m->req_lock); ... p9_fd_cancelled() ... ... spin_unlock(&m->req_lock); // status rewrite p9_client_cb(m->client, req, REQ_STATUS_ERROR) // first remove list_del(&req->req_list); ...

  spin_lock(&m->req_lock) ... // second remove list_del(&req->req_list); spin_unlock(&m->req_lock) ...

Commit 74d6a5d56629 ("9p/trans_fd: Fix concurrency del of req_list in p9_fd_cancelled/p9_read_work") fixes a concurrency issue in the 9p filesystem client where the req_list could be deleted simultaneously by both p9_read_work and p9_fd_cancelled functions, but for the case where req->status equals REQ_STATUS_RCVD.

Update the check for req->status in p9_fd_cancelled to skip processing not just received requests, but anything that is not SENT, as whatever changed the state from SENT also removed the request from its list.

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

updated the check from status == RECV || status == ERROR to status != SENT

In the Linux kernel, the following vulnerability has been resolved:

exfat: validate cluster allocation bits of the allocation bitmap

syzbot created an exfat image with cluster bits not set for the allocation bitmap. exfat-fs reads and uses the allocation bitmap without checking this. The problem is that if the start cluster of the allocation bitmap is 6, cluster 6 can be allocated when creating a directory with mkdir. exfat zeros out this cluster in exfat_mkdir, which can delete existing entries. This can reallocate the allocated entries. In addition, the allocation bitmap is also zeroed out, so cluster 6 can be reallocated. This patch adds exfat_test_bitmap_range to validate that clusters used for the allocation bitmap are correctly marked as in-use.(CVE-2025-40307)

In the Linux kernel, the following vulnerability has been resolved:

batman-adv: stop tp_meter sessions during mesh teardown

TP meter sessions remain linked on bat_priv->tp_list after the netlink request has already finished. When the mesh interface is removed, batadv_mesh_free() currently tears down the mesh without first draining these sessions.

A running sender thread or a late incoming tp_meter packet can then keep processing against a mesh instance which is already shutting down. Synchronize tp_meter with the mesh lifetime by stopping all active sessions from batadv_mesh_free() and waiting for sender threads to exit before teardown continues.(CVE-2026-46208)

In the Linux kernel, the following vulnerability has been resolved:

sctp: diag: reject stale associations in dump_one path

The SCTP exact sock_diag lookup can hold a transport reference, block on lock_sock(sk), and then resume after sctp_association_free() has marked the association dead and freed its bind address list.

When that happens, inet_assoc_attr_size() and inet_diag_msg_sctpasoc_fill() can still dereference association state that is no longer valid for reporting. In particular, inet_diag_msg_sctpasoc_fill() may read an empty bind-address list as a real sctp_sockaddr_entry and trigger an out-of-bounds read from unrelated association memory.

Reject the association after taking the socket lock if it has been reaped or detached from the endpoint, and report the lookup as stale. This keeps the exact dump-one path from formatting torn association state.(CVE-2026-52917)

In the Linux kernel, the following vulnerability has been resolved:

libceph: Fix potential out-of-bounds access in crush_decode()

A message of type CEPH_MSG_OSD_MAP containing a crush map with at least one bucket has two fields holding the bucket algorithm. If the values in these two fields differ, an out-of-bounds access can occur. This is the case because the first algorithm field (alg) is used to allocate the correct amount of memory for a bucket of this type, while the second algorithm field inside the bucket (b->alg) is used in the subsequent processing.

This patch fixes the issue by adding a check that compares alg and b->alg and aborts the processing in case they differ. Furthermore, b->alg is set to 0 in this case, because the destruction of the crush map also uses this field to determine the bucket type, which can again result in an out-of-bounds access when trying to free the memory pointed to by the fields of the bucket. To correctly free the memory allocated for the bucket in such a case, the corresponding call to kfree is moved from the algorithm-specific crush_destroy_bucket functions to the generic crush_destroy_bucket().(CVE-2026-52955)

In the Linux kernel, the following vulnerability has been resolved:

hv_netvsc: use kmap_local_page in netvsc_copy_to_send_buf

netvsc_copy_to_send_buf() copies page buffer entries into the VMBus send buffer using phys_to_virt() on the entry PFN. Entries for the RNDIS header and the skb linear data come from kmalloc'd memory and are always in the kernel direct map, but entries for skb fragments reference page cache or user pages, which on 32-bit x86 with CONFIG_HIGHMEM=y can live above the LOWMEM boundary. For such a page phys_to_virt() returns an address outside the direct map and the subsequent memcpy() faults on the transmit softirq path, which is fatal.

Map the pages with kmap_local_page() instead, handling two properties of the page buffer entries:

• pb[i].pfn is a Hyper-V PFN at HV_HYP_PAGE_SIZE (4K) granularity, not a native PFN. Reconstruct the physical address first and derive the native page from it, so the mapping stays correct where PAGE_SIZE > HV_HYP_PAGE_SIZE (e.g. arm64 with 64K pages).

• Since commit 41a6328b2c55 ("hv_netvsc: Preserve contiguous PFN grouping in the page buffer array"), an entry describes a full physically contiguous fragment and pb[i].len can exceed PAGE_SIZE, while kmap_local_page() maps a single page. Copy page by page, splitting at native page boundaries.

The copy path only handles packets smaller than the send section size (6144 bytes by default); larger packets take the cp_partial path where only the RNDIS header is copied. So entries here are bounded by the section size and a copy is split at most once on 4K-page systems. On !CONFIG_HIGHMEM configs kmap_local_page() folds to page_address() and no mapping work is added.(CVE-2026-53199)

In the Linux kernel, the following vulnerability has been resolved:

sctp: fix uninit-value in __sctp_rcv_asconf_lookup()

__sctp_rcv_asconf_lookup() in net/sctp/input.c only checks that the ASCONF chunk can hold the ADDIP header and a parameter header, then calls af->from_addr_param(), which reads the full address (16 bytes for IPv6) trusting the parameter's declared length.

An unauthenticated peer can send a truncated trailing ASCONF chunk that declares an IPv6 address parameter but stops after the 4-byte parameter header; reached from the no-association lookup path, from_addr_param() then reads uninitialized bytes past the parameter.

Impact: an unauthenticated SCTP peer makes the receive path read up to 16 bytes of uninitialized memory past a truncated ASCONF address parameter.

The sibling __sctp_rcv_init_lookup() bounds parameters with sctp_walk_params(); this path open-codes the fetch and omits the bound. Verify the whole address parameter lies within the chunk before from_addr_param() reads it, the same class of fix as commit 51e5ad549c43 ("net: sctp: fix KMSAN uninit-value in sctp_inq_pop").(CVE-2026-53225)

In the Linux kernel, the following vulnerability has been resolved:

tipc: fix slab-use-after-free Read in tipc_aead_decrypt_done

tipc_aead_decrypt() goes straight from tipc_bearer_hold(b) to crypto_aead_decrypt(req) without taking a reference on the netns, unlike the encrypt path. When crypto_aead_decrypt() is offloaded asynchronously (e.g. the SIMD aead wrapper queuing to cryptd), the cryptd worker runs tipc_aead_decrypt_done() later. If the bearer's netns is torn down in the meantime, cleanup_net() -> tipc_exit_net() -> tipc_crypto_stop() frees the per-netns tipc_crypto, and the completion then reads it: tipc_aead_decrypt_done() dereferences aead->crypto->stats and aead->crypto->net, and tipc_crypto_rcv_complete() dereferences aead->crypto->aead[] and the node table -- reading freed memory.

Decoded KASAN splat (v7.1-rc7, CONFIG_KASAN_INLINE + TIPC + TIPC_CRYPTO):

BUG: KASAN: slab-use-after-free in tipc_aead_decrypt_done (net/tipc/crypto.c:999) Read of size 8 at addr ffff8881056258a8 by task kworker/u16:2/51 Workqueue: events_unbound Call Trace: tipc_aead_decrypt_done (net/tipc/crypto.c:999) process_one_work (kernel/workqueue.c:3314) worker_thread (kernel/workqueue.c:3397 kernel/workqueue.c:3478) kthread (kernel/kthread.c:436) ret_from_fork (arch/x86/kernel/process.c:158) ret_from_fork_asm (arch/x86/entry/entry_64.S:245)

Allocated by task 169: __kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415) tipc_crypto_start (net/tipc/crypto.c:1502) tipc_init_net (net/tipc/core.c:72) ops_init (net/core/net_namespace.c:137) setup_net (net/core/net_namespace.c:446) copy_net_ns (net/core/net_namespace.c:579) create_new_namespaces (kernel/nsproxy.c:132) __x64_sys_unshare (kernel/fork.c:3316) do_syscall_64 (arch/x86/entry/syscall_64.c:63) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)

Freed by task 8: kfree (mm/slub.c:6566) tipc_exit_net (net/tipc/core.c:119) cleanup_net (net/core/net_namespace.c:704) process_one_work (kernel/workqueue.c:3314) kthread (kernel/kthread.c:436)

This is the same class of bug that commit e279024617134 ("net/tipc: fix slab-use-after-free Read in tipc_aead_encrypt_done") fixed for the encrypt side. The encrypt path takes maybe_get_net(aead->crypto->net) before crypto_aead_encrypt() and drops it with put_net() on the synchronous return paths and in tipc_aead_encrypt_done(); the -EINPROGRESS/-EBUSY return keeps the reference for the async callback to release. The decrypt path was left without the equivalent guard.

Mirror the encrypt-side fix on the decrypt path: take a net reference before crypto_aead_decrypt() (failing with -ENODEV and the matching bearer put if it cannot be acquired), keep it across the -EINPROGRESS/-EBUSY async return, and drop it with put_net() on the synchronous success/error return and at the end of tipc_aead_decrypt_done().

Reproduced under KASAN on v7.1-rc7: a UDP bearer with a cluster key is flooded with crafted encrypted frames from an unknown peer (driving the cluster-key decrypt path) while the bearer's netns is repeatedly torn down. The completion must run asynchronously to outlive tipc_crypto_stop(); on x86 the stock aesni gcm(aes) now decrypts synchronously, so the async path was exercised via cryptd offload. The unguarded aead->crypto dereference in tipc_aead_decrypt_done() is the unpatched upstream path; tipc_aead_decrypt() still lacks maybe_get_net(aead->crypto->net), so the completion can outlive the free on any config where crypto_aead_decrypt() goes async.

Found by 0sec automated security-research tooling (https://0sec.ai).(CVE-2026-63801)

In the Linux kernel, the following vulnerability has been resolved:

netfilter: conntrack: tcp: do not force CLOSE on invalid-seq RST without direction check

An unintended behavior in the TCP conntrack state machine allows a connection to be forced into the CLOSE state using an RST packet with an invalid sequence number.

Specifically, after a SYN packet is observed, an RST with an invalid SEQ can transition the conntrack entry to TCP_CONNTRACK_CLOSE, regardless of whether the RST corresponds to the expected reply direction. The relevant code path assumes the RST is a response to an outgoing SYN, but does not validate packet direction or ensure that a matching SYN was actually sent in the opposite direction.

As a result, a crafted packet sequence consisting of a SYN followed by an invalid-sequence RST can prematurely terminate an active NAT entry. This makes connection teardown easier than intended.

So, tighten the state transition logic to ensure that RST-triggered CLOSE transitions only occur when the RST is a valid response to a previously observed SYN in the correct direction.(CVE-2026-63913)

In the Linux kernel, the following vulnerability has been resolved:

xfrm: route MIGRATE notifications to caller's netns

xfrm_send_migrate() in net/xfrm/xfrm_user.c and pfkey_send_migrate() in net/key/af_key.c both hardcode &init_net for the multicast that announces a successful XFRM_MSG_MIGRATE / SADB_X_MIGRATE.

XFRM_MSG_MIGRATE arrives on a per-netns NETLINK_XFRM socket, and the rest of the xfrm/af_key netlink path was made netns-aware in 2008. The other 14 multicast paths in xfrm_user.c route their event using xs_net(x), xp_net(xp) or sock_net(skb->sk); only the migrate path was missed.

Two consequences of the init_net hardcoding:

1. The notification (selector, old/new endpoint addresses, and the km_address) is delivered to listeners on init_net's XFRMNLGRP_MIGRATE / pfkey BROADCAST_ALL groups rather than on the issuing netns. An IKE daemon running in init_net therefore receives migration notifications originating from any other netns on the host.

2. An IKE daemon running inside a non-init netns and subscribed to its own XFRMNLGRP_MIGRATE / pfkey groups never receives the notification of its own migration. IKEv2 MOBIKE / address-update handling inside a netns is silently broken.

Thread struct net through km_migrate() and the xfrm_mgr.migrate function pointer, drop the &init_net override in xfrm_send_migrate() and pfkey_send_migrate(), and pass the caller's net (already in scope in xfrm_migrate() via sock_net(skb->sk)) all the way down. struct xfrm_mgr is in-tree only and not exported as a stable API, so the function-pointer signature change is internal.

pfkey_broadcast() is already netns-aware via net_generic(net, pfkey_net_id) since the pernet conversion. The five other pfkey_broadcast() callers in af_key.c already pass xs_net(x), sock_net(sk) or a per-netns net, so this only removes the &init_net outlier.(CVE-2026-63914)

In the Linux kernel, the following vulnerability has been resolved:

sctp: fix race between sctp_wait_for_connect and peeloff

sctp_wait_for_connect() drops and re-acquires the socket lock while waiting for the association to reach ESTABLISHED state. During this window, another thread can peeloff the association to a new socket via getsockopt(SCTP_SOCKOPT_PEELOFF), changing asoc->base.sk. After re-acquiring the old socket lock, sctp_wait_for_connect() returns success without noticing the migration — the caller then accesses the association under the wrong lock in sctp_datamsg_from_user().

Add the same sk != asoc->base.sk check that sctp_wait_for_sndbuf() already has, returning an error if the association was migrated while we slept.(CVE-2026-63971)

In the Linux kernel, the following vulnerability has been resolved:

batman-adv: tt: fix negative last_changeset_len

batadv_piv_tt::last_changeset_len len was declared as s16, but the field is never intended to hold a negative value. When a value greater than 32767 is assigned, it wraps to a negative signed integer.

In batadv_send_my_tt_response(), last_changeset_len is temporarily widened to s32. The incorrectly negative s16 value propagates into the s32, causing batadv_tt_prepare_tvlv_local_data() to allocate a full sized buffer but populates only a small portion of it with the collected changeset. All remaining bits are kept uninitialized.

Using an u16 avoids this type confusion and ensures that no (negative) sign extension is performed in batadv_send_my_tt_response().(CVE-2026-64089)

In the Linux kernel, the following vulnerability has been resolved:

batman-adv: bla: avoid double decrement of bla.num_requests

The bla.num_requests is increased when no request_sent was in progress. And it is decremented in various places (announcement was received, backbone is purged, periodic work). But the check if the request_sent is actually set to a specific state and the atomic_dec/_inc are not safe because they are not atomic (TOCTOU) and multiple such code portions can run concurrently.

At the same time, it is necessary to modify request_sent (state) and bla.num_requests atomically. Otherwise batadv_bla_send_request() might set request_sent to 1 and is interrupted. batadv_handle_announce() can then set request_sent back to 0 and decrement num_requests before batadv_bla_send_request() incremented it.

The two operations must therefore be locked. And since state (request_sent) and wait_periods are only accessed inside this lock, they can be converted to simpler datatypes. And to avoid that the bla.num_requests is touched by a parallel running context with a valid backbone_gw reference after batadv_bla_purge_backbone_gw() ran, a third state "stopped" is required to correctly signal that a backbone_gw is in the state of being cleaned up.(CVE-2026-64095)

In the Linux kernel, the following vulnerability has been resolved:

net: qualcomm: rmnet: fix endpoint use-after-free in rmnet_dellink()

rmnet_dellink() removes the endpoint from the hash table with hlist_del_init_rcu() and then immediately frees it with kfree(). However, RCU readers on the receive path (rmnet_rx_handler -> __rmnet_map_ingress_handler) may still hold a reference to the endpoint and dereference ep->egress_dev after the memory has been freed. The endpoint is a kmalloc-32 object, and the stale read at offset 8 corresponds to the egress_dev pointer.

BUG: unable to handle page fault for address: ffffffffde942eef Oops: 0002 [#1] SMP NOPTI CPU: 1 UID: 0 PID: 137 Comm: poc_write Not tainted 7.0.0+ #4 PREEMPTLAZY RIP: 0010:rmnet_vnd_rx_fixup (rmnet_vnd.c:27) Call Trace: <TASK> __rmnet_map_ingress_handler (rmnet_handlers.c:48 rmnet_handlers.c:101) rmnet_rx_handler (rmnet_handlers.c:129 rmnet_handlers.c:235) __netif_receive_skb_core.constprop.0 (net/core/dev.c:6096) __netif_receive_skb_one_core (net/core/dev.c:6208) netif_receive_skb (net/core/dev.c:6467) tun_get_user (drivers/net/tun.c:1955) tun_chr_write_iter (drivers/net/tun.c:2003) vfs_write (fs/read_write.c:688) ksys_write (fs/read_write.c:740) </TASK>

Add an rcu_head field to struct rmnet_endpoint and replace kfree() with kfree_rcu() so the endpoint memory remains valid through the RCU grace period. Also remove the rmnet_vnd_dellink() call and inline only the nr_rmnet_devs decrement, since rmnet_vnd_dellink() would set ep->egress_dev to NULL during the grace period, creating a data race with lockless readers.(CVE-2026-64188)

In the Linux kernel, the following vulnerability has been resolved: tipc: fix out-of-bounds read in broadcast Gap ACK blocks. A broadcast PROTOCOL/STATE_MSG can carry a Gap ACK blocks record in its data area. tipc_get_gap_ack_blks() only verifies that the record's len field is self-consistent with its ugack_cnt/bgack_cnt counts (sz == struct_size(p, gacks, ugack_cnt + bgack_cnt)); it does not check that the record actually fits in the message data area, msg_data_sz(). The unicast caller tipc_link_proto_rcv() bounds it, but the broadcast caller tipc_bcast_sync_rcv() discards the returned size, so tipc_link_advance_transmq() copies the record off the receive skb with an attacker-controlled count, leading to an out-of-bounds read. This could allow an attacker to read beyond the allocated buffer, potentially causing information disclosure or system crash.(CVE-2026-64450)

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: btusb: fix use-after-free on registration failure

Make sure to release the sibling interfaces in case controller registration fails to avoid use-after-free and double-free when they are eventually disconnected.

This issue was reported by Sashiko while reviewing a fix for a wakeup source leak in the btusb probe errors paths.(CVE-2026-64471)

In the Linux kernel, the following vulnerability has been resolved:

ALSA: firewire: isight: bound the sample count to the packet payload

isight_packet() takes the frame count from the device iso packet and checks it only against the device claimed iso length.

count = be32_to_cpu(payload->sample_count);
if (likely(count <= (length - 16) / 4))
	isight_samples(isight, payload->samples, count);

length is the iso header data_length. It can be up to 0xffff. So the gate allows a count up to about 16379. isight_samples() then copies count frames out of payload->samples into the PCM DMA buffer.

payload->samples holds only 2 * MAX_FRAMES_PER_PACKET values. The device multiplexes two samples per frame. A count past MAX_FRAMES_PER_PACKET reads past the payload. A count past the buffer size writes past runtime->dma_area. The smallest PCM buffer is larger than MAX_FRAMES_PER_PACKET. Bounding the count to MAX_FRAMES_PER_PACKET keeps both the read and the write in range.

A malicious or faulty Apple iSight on the FireWire bus reaches this during a normal capture.

Add the MAX_FRAMES_PER_PACKET bound to the gate.(CVE-2026-64483)

In the Linux kernel, the following vulnerability has been resolved:

libceph: Reject monmaps advertising zero monitors

A message of type CEPH_MSG_MON_MAP contains a monmap that is sent from a monitor to the client. This monmap contains information about the existing monitors in the cluster. Currently, a monmap indicating that there are zero monitors in the cluster is treated as valid. However, it is impossible to have zero monitors in the cluster and still receive a valid monmap from a monitor. Therefore, such a monmap must be corrupted and should be treated as invalid. Furthermore, a monmap with a monitor count of zero can subsequently crash the client when attempting to open a session with a monitor in __open_session(). This happens because the "BUG_ON(monc->monmap->num_mon < 1)" assertion in pick_new_mon() is triggered.

This patch extends a check in ceph_monmap_decode() to also reject arriving mon_maps with num_mon == 0 rather than only with num_mon > CEPH_MAX_MON.

idryomov: drop "log output for unusual values of num_mon" part

In the Linux kernel, the following vulnerability has been resolved:

libceph: refresh auth->authorizer_buf{,_len} after authorizer update

ceph_x_create_authorizer() caches au->buf->vec.iov_base and au->buf->vec.iov_len in struct ceph_auth_handshake. These cached values are then used by the messenger connect code when sending the authorizer.

ceph_x_update_authorizer() can rebuild the authorizer when a newer service ticket is available. If the rebuilt authorizer no longer fits in the existing buffer, ceph_x_build_authorizer() drops its reference to au->buf and allocates a new one. If this is the final reference, ceph_buffer_put() frees the old ceph_buffer and its vec.iov_base, but auth->authorizer_buf still points at that freed memory.

A subsequent msgr1 reconnect can therefore queue the stale pointer and trigger a KASAN slab-use-after-free in _copy_from_iter() while tcp_sendmsg() copies the authorizer.

Refresh auth->authorizer_buf and auth->authorizer_buf_len after a successful authorizer rebuild so the messenger sends the current buffer.(CVE-2026-68156)

In the Linux kernel, the following vulnerability has been resolved:

media: cx231xx: fix devres lifetime

USB drivers bind to USB interfaces and any device managed resources should have their lifetime tied to the interface rather than parent USB device. This avoids issues like memory leaks when drivers are unbound without their devices being physically disconnected (e.g. on probe deferral or configuration changes).

Fix the driver state lifetime so that it is released on driver unbind.(CVE-2026-68227)

In the Linux kernel, the following vulnerability has been resolved:

IB/mad: Drop unmatched RMPP responses before reassembly

Kernel-handled RMPP receive processing starts reassembly for active DATA responses before the response is matched to an outstanding send. The normal match happens later, after ib_process_rmpp_recv_wc() has either assembled a complete message or consumed the segment.

That ordering lets an unsolicited response that routes to a kernel RMPP agent by the high TID bits allocate or extend RMPP receive state before the full TID and source address are checked against a real request. A reordered burst can therefore reach the receive-side insertion path even though the response would not match any send.

For kernel-handled RMPP DATA responses, require the existing ib_find_send_mad() match before entering RMPP reassembly. The matcher already checks the full TID, management class and source address/GID against the agent wait, backlog and in-flight send lists. If there is no match, drop the response without creating RMPP state.

This leaves the RMPP window behavior unchanged and only rejects responses that have no corresponding request.(CVE-2026-68425)

In the Linux kernel, the following vulnerability has been resolved:

ntfs: sanitize MFT references returned from ntfs_lookup_inode_by_name()

ntfs_lookup_inode_by_name() returns MFT references read from directory index entries on disk. These values are untrusted, but the function can currently return an error-marked MFT reference to its callers without validating it.

Callers later decode lookup failures with MREF_ERR(). A crafted NTFS image can set the MREF error bit while leaving the low bits as an arbitrary value, causing callers to consume a bogus pseudo-errno instead of treating the lookup result as corrupted on-disk metadata.

Fix this at the source by normalizing every error-marked MFT reference returned from ntfs_lookup_inode_by_name() to ERR_MREF(-EIO). Apply this to all four directory lookup return paths so every caller gets a validated result without needing additional checks or an API change.

This keeps the sanitization in the common lookup helper, which is cleaner than duplicating validation in each caller.(CVE-2026-72188)

In the Linux kernel, the following vulnerability has been resolved:

RDMA/mlx5: Fix undefined shift of user RQ WQE size

set_rq_size() computes the RQ WQE size as "1 << rq_wqe_shift" based on the user-provided rq_wqe_shift, which is only checked to be greater than 32, so shifts of 32 are still accepted. A shift of 31 also overflows a signed integer, leading to undefined behavior.

Use check_shl_overflow() to compute the RQ WQE size and reject any invalid values.(CVE-2026-74297)

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: hci_core: Fix UAF in hci_unregister_dev()

hci_unregister_dev() does not disable cmd_timer and ncmd_timer before the hci_dev structure is freed. If a timeout fires during device teardown, the callback dereferences freed memory (including the hdev->reset function pointer), leading to a use-after-free.

Add disable_delayed_work_sync() calls alongside the existing disable_work_sync() calls to ensure both timers are fully quiesced before teardown proceeds.(CVE-2026-74302)

In the Linux kernel, the following vulnerability has been resolved:

RDMA/rxe: Copy WQE to local buffer in non-SRQ receive path

For non-SRQ QPs, the responder reads WQE fields directly from the shared queue buffer mapped into userspace. This allows a malicious user to modify fields like num_sge or sge entries while the kernel is processing the WQE, leading to out-of-bounds reads in rxe_resp_check_length() and copy_data().

Introduce get_recv_wqe() that validates num_sge and copies the WQE to a kernel-local buffer before processing, matching the approach already used for SRQ WQEs in get_srq_wqe(). The srq_wqe buffer is reused since SRQ and non-SRQ paths are mutually exclusive per QP.(CVE-2026-74377)

In the Linux kernel, the following vulnerability has been resolved:

RDMA/srpt: fix integer overflow in immediate data length check

imm_buf->len is a user-controlled uint32_t received from the network. Adding it to imm_data_offset without overflow checking allows a malicious initiator to send len=0xFFFFFFFF, causing req_size to wrap around to a small value, bypassing the bounds check, and subsequently passing a ~4GB length to sg_init_one().

Use check_add_overflow() to detect wrapping before the comparison.(CVE-2026-74394)

In the Linux kernel, the following vulnerability has been resolved:

RDMA/mlx5: Fix devx subscribe-event unwind NULL dereference

MLX5_IB_METHOD_DEVX_SUBSCRIBE_EVENT() links event_sub into sub_list before initializing the fields used by the shared error path.

If eventfd_ctx_fdget() then fails, the unwind path dereferences event_sub->ev_file in uverbs_uobject_put() and calls subscribe_event_xa_dealloc() with an unset xa_key_level1.

subscribe_event_xa_alloc() creates the XA entry exactly once for a given key_level1, on the first occurrence of that key. The unwind path must therefore call subscribe_event_xa_dealloc() exactly once for it as well.

Enforce that by adding devx_key_in_sub_list() and calling subscribe_event_xa_dealloc() only when the last matching pending entry is being cleaned up.(CVE-2026-74395)

In the Linux kernel, the following vulnerability has been resolved:

IB/mlx5: Fix transport-domain rollback and initialize lb mutex earlier

mlx5_ib_alloc_transport_domain() allocates a transport domain and then may fail in mlx5_ib_enable_lb(). In that case, the allocated TD is leaked.

Fix this by deallocating the TD when mlx5_ib_enable_lb() returns an error. Also return 0 explicitly in the no-loopback-capability success branch, and move dev->lb.mutex initialization to mlx5_ib_stage_init_init().(CVE-2026-74397)

In the Linux kernel, the following vulnerability has been resolved:

ALSA: usb-audio: fix OOB write in snd_usbmidi_akai_output()

snd_usbmidi_akai_output() computes its fill-loop bound

buf_end = ep->max_transfer - MAX_AKAI_SYSEX_LEN - 1;

as a signed int, so a small device-advertised bulk-OUT max_transfer makes buf_end negative. The loop guard then compares the u32 urb->transfer_buffer_length against that negative int: the usual arithmetic conversion turns buf_end into a large unsigned value, so the guard stays true and each iteration keeps appending SysEx framing and payload bytes past the end of the URB transfer buffer, which is only max_transfer bytes long.

A USB device that advertises a tiny bulk-OUT endpoint can therefore trigger an attacker-length- and content-controlled heap out-of-bounds write when a process writes to the created /dev/snd/midiCD node.

Return early when there is no room for even one SysEx, so the loop is never entered with a bound that would wrap. The loop is the last statement of the function, so bailing out is equivalent to it not running.

Discovered by XBOW, triaged by Baul Lee <(CVE-2026-74499)

In the Linux kernel, the following vulnerability has been resolved: sctp: keep chunk->transport in step with the list it is queued on. __sctp_outq_flush_rtx() moves a gap-acked chunk onto another transport's transmitted list without updating chunk->transport. The chunk then sits on a live transport's list while chunk->transport still names a different one. If that transport is removed - sctp_assoc_rm_peer() from an ASCONF Delete-IP - sctp_transport_free() RCU-frees it and the chunk is left with a dangling pointer. A SACK that reneges on the TSN clears the flag, and the next SACK reaches inside the freed transport. KASAN reports a slab-use-after-free read in sctp_check_transmitted(), freed from sctp_assoc_rm_peer().(CVE-2026-74588)

In the Linux kernel, a deadlock vulnerability has been found in the ceph filesystem. A reader can hang forever in __ceph_get_caps() when the client no longer holds FILE_RD, but local cap state still says that the capability is already wanted (via mds_wanted). One way to trigger this is through MDS cap revocation. If another client performs a conflicting operation, the MDS can revoke FILE_RD from the reader; the next read then has to reacquire FILE_RD. If the cap update that should request FILE_RD never reaches the MDS after cap->mds_wanted was raised, the reader is left holding only non-file caps while local mds_wanted still includes the file read caps, causing the reader to wait indefinitely.(CVE-2026-80527)

In the Linux kernel, the following vulnerability has been resolved:

libceph: fix OOB read in decode_watchers() via missing bounds check

ceph_start_decoding() validates that struct_len bytes remain in the buffer after the encoding header, but accepts struct_len=0 as valid: ceph_decode_need(p, end, 0, bad) always passes. When a malicious or compromised OSD sends an obj_list_watch_response_t reply with struct_len=0, ceph_start_decoding() returns success with p == end, leaving zero bytes guaranteed for subsequent reads.

The immediately following ceph_decode_32(p) in decode_watchers() has no preceding bounds check. With p == end this is a 4-byte read past the validated buffer boundary. The garbage value is then passed directly to kzalloc_objs() as the watcher count.

The sibling function decode_watcher() already uses the safe variants (ceph_decode_copy_safe, ceph_decode_64_safe, ceph_decode_skip_32) after its own ceph_start_decoding() call. decode_watchers() is the only site that uses the bare variant, confirming an oversight.

Fix by replacing ceph_decode_32(p) with ceph_decode_32_safe(p, end, *num_watchers, bad), consistent with the established pattern.

Attacker model: a malicious or compromised OSD in a multi-tenant Ceph deployment (e.g. cloud) can trigger this against any kernel client that calls CEPH_OSD_OP_LIST_WATCHERS, without any further privileges beyond OSD session establishment.

idryomov: trim changelog