CVE-2025-21817

The Linux Kernel, the operating system core itself.

Security Fix(es):

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

IORING_OP_READ did not correctly consume the provided buffer list when read i/o returned < 0 (except for -EAGAIN and -EIOCBQUEUED return). This can lead to a potential use-after-free when the completion via io_rw_done runs at separate context.(CVE-2023-52926)

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

NFS: Fix potential buffer overflowin nfs_sysfs_link_rpc_client()

name is char[64] where the size of clnt->cl_program->name remains unknown. Invoking strcat() directly will also lead to potential buffer overflow. Change them to strscpy() and strncat() to fix potential issues.(CVE-2024-54456)

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

wifi: mac80211: fix mbss changed flags corruption on 32 bit systems

On 32-bit systems, the size of an unsigned long is 4 bytes, while a u64 is 8 bytes. Therefore, when using or_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE), the code is incorrectly searching for a bit in a 32-bit variable that is expected to be 64 bits in size, leading to incorrect bit finding.

Solution: Ensure that the size of the bits variable is correctly adjusted for each architecture.

Call Trace: ? show_regs+0x54/0x58 ? __warn+0x6b/0xd4 ? ieee80211_link_info_change_notify+0xcc/0xd4 [mac80211] ? report_bug+0x113/0x150 ? exc_overflow+0x30/0x30 ? handle_bug+0x27/0x44 ? exc_invalid_op+0x18/0x50 ? handle_exception+0xf6/0xf6 ? exc_overflow+0x30/0x30 ? ieee80211_link_info_change_notify+0xcc/0xd4 [mac80211] ? exc_overflow+0x30/0x30 ? ieee80211_link_info_change_notify+0xcc/0xd4 [mac80211] ? ieee80211_mesh_work+0xff/0x260 [mac80211] ? cfg80211_wiphy_work+0x72/0x98 [cfg80211] ? process_one_work+0xf1/0x1fc ? worker_thread+0x2c0/0x3b4 ? kthread+0xc7/0xf0 ? mod_delayed_work_on+0x4c/0x4c ? kthread_complete_and_exit+0x14/0x14 ? ret_from_fork+0x24/0x38 ? kthread_complete_and_exit+0x14/0x14 ? ret_from_fork_asm+0xf/0x14 ? entry_INT80_32+0xf0/0xf0

restore no-op path for no changes

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

usb: xhci: Fix NULL pointer dereference on certain command aborts

If a command is queued to the final usable TRB of a ring segment, the enqueue pointer is advanced to the subsequent link TRB and no further. If the command is later aborted, when the abort completion is handled the dequeue pointer is advanced to the first TRB of the next segment.

If no further commands are queued, xhci_handle_stopped_cmd_ring() sees the ring pointers unequal and assumes that there is a pending command, so it calls xhci_mod_cmd_timer() which crashes if cur_cmd was NULL.

Don't attempt timer setup if cur_cmd is NULL. The subsequent doorbell ring likely is unnecessary too, but it's harmless. Leave it alone.

This is probably Bug 219532, but no confirmation has been received.

The issue has been independently reproduced and confirmed fixed using a USB MCU programmed to NAK the Status stage of SET_ADDRESS forever. Everything continued working normally after several prevented crashes.(CVE-2024-57981)

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

ocfs2: handle a symlink read error correctly

Patch series "Convert ocfs2 to use folios".

Mark did a conversion of ocfs2 to use folios and sent it to me as a giant patch for review ;-)

So I've redone it as individual patches, and credited Mark for the patches where his code is substantially the same. It's not a bad way to do it; his patch had some bugs and my patches had some bugs. Hopefully all our bugs were different from each other. And hopefully Mark likes all the changes I made to his code!

This patch (of 23):

If we can't read the buffer, be sure to unlock the page before returning.(CVE-2024-58001)

In the Linux kernel, the…

The Linux Kernel, the operating system core itself.

Security Fix(es):

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

IORING_OP_READ did not correctly consume the provided buffer list when read i/o returned < 0 (except for -EAGAIN and -EIOCBQUEUED return). This can lead to a potential use-after-free when the completion via io_rw_done runs at separate context.(CVE-2023-52926)

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

f2fs: fix to shrink read extent node in batches

We use rwlock to protect core structure data of extent tree during its shrink, however, if there is a huge number of extent nodes in extent tree, during shrink of extent tree, it may hold rwlock for a very long time, which may trigger kernel hang issue.

This patch fixes to shrink read extent node in batches, so that, critical region of the rwlock can be shrunk to avoid its extreme long time hold.(CVE-2024-41935)

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

dma-debug: fix a possible deadlock on radix_lock

radix_lock() shouldn't be held while holding dma_hash_entry[idx].lock otherwise, there's a possible deadlock scenario when dma debug API is called holding rq_lock():

CPU0 CPU1 CPU2 dma_free_attrs() check_unmap() add_dma_entry() __schedule() //out (A) rq_lock() get_hash_bucket() (A) dma_entry_hash check_sync() (A) radix_lock() (W) dma_entry_hash dma_entry_free() (W) radix_lock() // CPU2's one (W) rq_lock()

CPU1 situation can happen when it extending radix tree and it tries to wake up kswapd via wake_all_kswapd().

CPU2 situation can happen while perf_event_task_sched_out() (i.e. dma sync operation is called while deleting perf_event using etm and etr tmc which are Arm Coresight hwtracing driver backends).

To remove this possible situation, call dma_entry_free() after put_hash_bucket() in check_unmap().(CVE-2024-47143)

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

dlm: fix possible lkb_resource null dereference

This patch fixes a possible null pointer dereference when this function is called from request_lock() as lkb->lkb_resource is not assigned yet, only after validate_lock_args() by calling attach_lkb(). Another issue is that a resource name could be a non printable bytearray and we cannot assume to be ASCII coded.

The log functionality is probably never being hit when DLM is used in normal way and no debug logging is enabled. The null pointer dereference can only occur on a new created lkb that does not have the resource assigned yet, it probably never hits the null pointer dereference but we should be sure that other changes might not change this behaviour and we actually can hit the mentioned null pointer dereference.

In this patch we just drop the printout of the resource name, the lkb id is enough to make a possible connection to a resource name if this exists.(CVE-2024-47809)

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

bcache: revert replacing IS_ERR_OR_NULL with IS_ERR again

Commit 028ddcac477b ("bcache: Remove unnecessary NULL point check in node allocations") leads a NULL pointer deference in cache_set_flush().

1721 if (!IS_ERR_OR_NULL(c->root)) 1722 list_add(&c->root->list, &c->btree_cache);

>From the above code in cache_set_flush(), if previous registration code fails before allocating c->root, it is possible c->root is NULL as what it is initialized. __bch_btree_node_alloc() never returns NULL but c->root is possible to be NULL at above line 1721.

This patch replaces IS_ERR() by IS_ERR_OR_NULL() to fix this.(CVE-2024-48881)

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

Root has patched CVE-2025-21817 in the linux package for Root:Debian:12. Multiple fixed versions available.

Root has patched CVE-2025-21817 in the linux package for Root:Ubuntu:22.04. Multiple fixed versions available.

Root has patched CVE-2025-21817 in the linux package for Root:Ubuntu:24.04. Multiple fixed versions available.

In the Linux kernel, the following vulnerability has been resolved: block: mark GFP_NOIO around sysfs ->store() sysfs ->store is called with queue freezed, meantime we have several ->store() callbacks(update_nr_requests, wbt, scheduler) to allocate memory with GFP_KERNEL which may run into direct reclaim code path, then potential deadlock can be caused. Fix the issue by marking NOIO around sysfs ->store()

• ice: Fix PTP NULL pointer dereference during VSI rebuild {CVE-2026-23210}
• tracing: Add recursion protection in kernel stack trace recording {CVE-2026-23138}
• mm/ptdump: take the memory hotplug lock inside ptdump_walk_pgd() {CVE-2025-38681}
• cpuset: fix warning when disabling remote partition {CVE-2025-71142}
• virtio: break and reset virtio devices on device_shutdown() {CVE-2025-38064}
• netdevsim: fix a race issue related to the operation on bpf_bound_progs list {CVE-2026-23126}
• atm: clip: Fix potential null-ptr-deref in to_atmarpd(). {CVE-2025-38460}
• idpf: fix error handling in the init_task on load {CVE-2026-23017}
• rxrpc: Fix recvmsg() unconditional requeue {CVE-2026-23066}
• block: zero non-PI portion of auto integrity buffer {CVE-2026-23007}
• can: netlink: can_changelink(): fix NULL pointer deref of struct can_priv::do_set_mode {CVE-2025-38665}
• virtio_net: Fix napi_skb_cache_put warning {CVE-2024-43835}
• crypto: af_alg - Disallow concurrent writes in af_alg_sendmsg {CVE-2025-39964}
• mptcp: fix race in mptcp_pm_nl_flush_addrs_doit() {CVE-2026-23169}
• net: fix segmentation of forwarding fraglist GRO {CVE-2026-23154}
• gfs2: Validate i_depth for exhash directories {CVE-2025-38710}
• KVM: Don't clobber irqfd routing type when deassigning irqfd {CVE-2026-23198}
• ipvlan: Make the addrs_lock be per port {CVE-2026-23103}
• xfs: fix freemap adjustments when adding xattrs to leaf blocks {CVE-2026-43158}
• can: mcp251xfd: fix infinite loop when xmit fails {CVE-2024-41088}
• RDMA/core: Check for the presence of LS_NLA_TYPE_DGID correctly {CVE-2025-71096}
• RDMA/mlx5: Fix error flow upon firmware failure for RQ destruction {CVE-2025-38161}
• scsi: qla2xxx: Validate sp before freeing associated memory {CVE-2025-71236}
• net/sched: netem: account for backlog updates from child qdisc {CVE-2024-56770}
• drm/i915/gt: fix refcount underflow in intel_engine_park_heartbeat {CVE-2026-31656}
• iavf: fix off-by-one issues in iavf_config_rss_reg() {CVE-2025-71087}
• net/sched: ets: fix divide by zero in the offload path {CVE-2026-23379}
• can: j1939: implement NETDEV_UNREGISTER notification handler {CVE-2025-39925}
• ipv4: nexthop: allocate skb dynamically in rtm_get_nexthop() {CVE-2026-31531}
• Bluetooth: L2CAP: Fix null-ptr-deref on l2cap_sock_ready_cb {CVE-2026-31510}
• ip6_tunnel: use skb_vlan_inet_prepare() in __ip6_tnl_rcv() {CVE-2026-23003}
• drm/i915/gt: Check set_default_submission() before deferencing {CVE-2026-31540}
• mac802154: check local interfaces before deleting sdata list {CVE-2024-57948}
• lib/buildid: use __kernel_read() for sleepable context {CVE-2026-23002}
• scsi: hisi_sas: Set debugfs_dir pointer to NULL after removing debugfs {CVE-2023-52808}
• net: fix memory leak in skb_segment_list for GRO packets {CVE-2026-22979}
• irqchip/imx-irqsteer: Handle runtime power management correctly {CVE-2024-42290}
• io_uring/io-wq: check IO_WQ_BIT_EXIT inside work run loop {CVE-2026-23113}
• net/sched: ets: Remove drr class from the active list if it changes to strict {CVE-2025-68815}
• net: bonding: fix NULL deref in bond_debug_rlb_hash_show {CVE-2026-31546}
• ipvs: fix ipv4 null-ptr-deref in route error path {CVE-2025-68813}
• openvswitch: fix lockup on tx to unregistering netdev with carrier {CVE-2025-21681}
• net: USB: Fix wrong-direction WARNING in plusb.c {CVE-2023-52742}
• module: Fix kernel panic when a symbol st_shndx is out of bounds {CVE-2026-31521}
• udf: Fix preallocation discarding at indirect extent boundary {CVE-2022-48946}
• net/mlx5: qos: Restrict RTNL area to avoid a lock cycle {CVE-2025-39947}
• scsi: core: Wake up the error handler when final completions race against each other {CVE-2026-23110}
• nbd: don't allow reconnect after disconnect {CVE-2025-21731}
• nfsd: check that server is running in unlock_filesystem {CVE-2026-22989}
• af_key: validate families in pfkey_send_migrate() {CVE-2026-31515}
• netfilter: nfnetlink_queue: acquire rcu_read_lock() in instance_destroy_rcu() {CVE-2024-36286} -…

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

block: mark GFP_NOIO around sysfs ->store()

sysfs ->store is called with queue freezed, meantime we have several ->store() callbacks(update_nr_requests, wbt, scheduler) to allocate memory with GFP_KERNEL which may run into direct reclaim code path, then potential deadlock can be caused.

Fix the issue by marking NOIO around sysfs ->store()