CVE-2026-64054

net: shaper: reject duplicate leaves in GROUP request

In the Linux kernel, the following vulnerability has been resolved: net: shaper: reject duplicate leaves in GROUP request net_shaper_nl_group_doit() does not deduplicate NET_SHAPER_A_LEAVES entries. When userspace supplies the same leaf handle twice, the same old-parent pointer lands twice in old_nodes[]. The cleanup loop double frees the parent. Of course the same parent may still be in old_nodes[] twice if we are moving multiple of its leaves. Note that this patch also implicitly fixes the fact that the i >= leaves_count path forgets to set ret.

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-63804

gfs2: fix use-after-free in gfs2_qd_dealloc

In the Linux kernel, the following vulnerability has been resolved: gfs2: fix use-after-free in gfs2_qd_dealloc gfs2_qd_dealloc(), called as an RCU callback from gfs2_qd_dispose(), accesses the superblock object sdp through qd->qd_sbd after freeing qd. It does so to decrement sd_quota_count and wake up sd_kill_wait. However, by the time the RCU callback runs, gfs2_put_super() may have already freed sdp via free_sbd(). This can happen when gfs2_quota_cleanup() is called during unmount: it disposes of quota objects via call_rcu() and then waits on sd_kill_wait with a 60-second timeout. If the timeout expires, or if gfs2_gl_hash_clear() triggers additional qd_put() calls that schedule more RCU callbacks after the wait completes, gfs2_put_super() will proceed to free the superblock while RCU callbacks referencing it are still pending. Add an rcu_barrier() before free_sbd() in gfs2_put_super() to ensure all pending RCU callbacks (including gfs2_qd_dealloc) have completed before the superblock is freed.

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-53296

mailbox: mailbox-test: free channels on probe error

In the Linux kernel, the following vulnerability has been resolved: mailbox: mailbox-test: free channels on probe error On probe error, free the previously obtained channels. This not only prevents a leak, but also UAF scenarios because the client structure will be removed nonetheless because it was allocated with devm.

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-53294

mailbox: mailbox-test: don't free the reused channel

In the Linux kernel, the following vulnerability has been resolved: mailbox: mailbox-test: don't free the reused channel The RX channel can be aliased to the TX channel if it has a different MMIO. This special case needs to be handled when freeing the channels otherwise a double-free occurs.

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-53286

idpf: fix double free and use-after-free in aux device error paths

In the Linux kernel, the following vulnerability has been resolved: idpf: fix double free and use-after-free in aux device error paths When auxiliary_device_add() fails in idpf_plug_vport_aux_dev() or idpf_plug_core_aux_dev(), the err_aux_dev_add label calls auxiliary_device_uninit() and falls through to err_aux_dev_init. The uninit call will trigger put_device(), which invokes the release callback (idpf_vport_adev_release / idpf_core_adev_release) that frees iadev. The fall-through then reads adev->id from the freed iadev for ida_free() and double-frees iadev with kfree(). Free the IDA slot and clear the back-pointer before uninit, while adev is still valid, then return immediately. Commit 65637c3a1811 ("idpf: fix UAF in RDMA core aux dev deinitialization") fixed the same use-after-free in the matching unplug path in this file but missed both probe error paths.

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-53272

erofs: fix use-after-free on sbi->sync_decompress

In the Linux kernel, the following vulnerability has been resolved: erofs: fix use-after-free on sbi->sync_decompress z_erofs_decompress_kickoff() can race with filesystem unmount, causing a use-after-free on sbi->sync_decompress. When I/O completes, z_erofs_endio() calls z_erofs_decompress_kickoff() to queue z_erofs_decompressqueue_work() asynchronously. Then, after all folios are unlocked, unmount workflow can proceed and sbi will be freed before accessing to sbi->sync_decompress. Thread (unmount) I/O completion kworker queue_work z_erofs_decompressqueue_work (all folios are unlocked) cleanup_mnt .. erofs_kill_sb erofs_sb_free kfree(sbi) access sbi->sync_decompress // UAF!!

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-53156

nvmem: core: fix use-after-free bugs in error paths

In the Linux kernel, the following vulnerability has been resolved: nvmem: core: fix use-after-free bugs in error paths Fix several instances of error paths in which we call __nvmem_device_put() - which may end up freeing the underlying memory and other resources - and then keep on using the nvmem structure. Always put the reference to the nvmem device as the last step before returning the error code.

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-53129

fs/mbcache: cancel shrink work before destroying the cache

In the Linux kernel, the following vulnerability has been resolved: fs/mbcache: cancel shrink work before destroying the cache mb_cache_destroy() calls shrinker_free() and then frees all cache entries and the cache itself, but it does not cancel the pending c_shrink_work work item first. If mb_cache_entry_create() schedules c_shrink_work via schedule_work() and the work item is still pending or running when mb_cache_destroy() runs, mb_cache_shrink_worker() will access the cache after its memory has been freed, causing a use-after-free. This is only reachable by a privileged user (root or CAP_SYS_ADMIN) who can trigger the last put of a mounted ext2/ext4/ocfs2 filesystem. Cancel the work item with cancel_work_sync() before calling shrinker_free(), ensuring the worker has finished and will not be rescheduled before the cache is torn down.

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-53120

PCI: use generic driver_override infrastructure

In the Linux kernel, the following vulnerability has been resolved: PCI: use generic driver_override infrastructure When a driver is probed through __driver_attach(), the bus' match() callback is called without the device lock held, thus accessing the driver_override field without a lock, which can cause a UAF. Fix this by using the driver-core driver_override infrastructure taking care of proper locking internally. Note that calling match() from __driver_attach() without the device lock held is intentional. [1]

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-53118

vdpa: use generic driver_override infrastructure

In the Linux kernel, the following vulnerability has been resolved: vdpa: use generic driver_override infrastructure When a driver is probed through __driver_attach(), the bus' match() callback is called without the device lock held, thus accessing the driver_override field without a lock, which can cause a UAF. Fix this by using the driver-core driver_override infrastructure taking care of proper locking internally. Note that calling match() from __driver_attach() without the device lock held is intentional. [1]

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-53117

s390/cio: use generic driver_override infrastructure

In the Linux kernel, the following vulnerability has been resolved: s390/cio: use generic driver_override infrastructure When a driver is probed through __driver_attach(), the bus' match() callback is called without the device lock held, thus accessing the driver_override field without a lock, which can cause a UAF. Fix this by using the driver-core driver_override infrastructure taking care of proper locking internally. Note that calling match() from __driver_attach() without the device lock held is intentional. [1]

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-53116

s390/ap: use generic driver_override infrastructure

In the Linux kernel, the following vulnerability has been resolved: s390/ap: use generic driver_override infrastructure When the AP masks are updated via apmask_store() or aqmask_store(), ap_bus_revise_bindings() is called after ap_attr_mutex has been released. This calls __ap_revise_reserved(), which accesses the driver_override field without holding any lock, racing against a concurrent driver_override_store() that may free the old string, resulting in a potential UAF. Fix this by using the driver-core driver_override infrastructure, which protects all accesses with an internal spinlock. Note that unlike most other buses, the AP bus does not check driver_override in its match() callback; the override is checked in ap_device_probe() and __ap_revise_reserved() instead. Also note that we do not enable the driver_override feature of struct bus_type, as AP - in contrast to most other buses - passes "" to sysfs_emit() when the driver_override pointer is NULL. Thus, printing "\n" instead of "(null)\n". Additionally, AP has a custom counter that is modified in the corresponding custom driver_override_store().

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-53109

powerpc/pgtable-frag: Fix bad page state in pte_frag_destroy

In the Linux kernel, the following vulnerability has been resolved: powerpc/pgtable-frag: Fix bad page state in pte_frag_destroy powerpc uses pt_frag_refcount as a reference counter for tracking it's pte and pmd page table fragments. For PTE table, in case of Hash with 64K pagesize, we have 16 fragments of 4K size in one 64K page. Patch series [1] "mm: free retracted page table by RCU" added pte_free_defer() to defer the freeing of PTE tables when retract_page_tables() is called for madvise MADV_COLLAPSE on shmem range. [1]: https://lore.kernel.org/all/7cd843a9-aa80-14f-5eb2-33427363c20@google.com/ pte_free_defer() sets the active flag on the corresponding fragment's folio & calls pte_fragment_free(), which reduces the pt_frag_refcount. When pt_frag_refcount reaches 0 (no active fragment using the folio), it checks if the folio active flag is set, if set, it calls call_rcu to free the folio, it the active flag is unset then it calls pte_free_now(). Now, this can lead to following problem in a corner case... [ 265.351553][ T183] BUG: Bad page state in process a.out pfn:20d62 [ 265.353555][ T183] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20d62 [ 265.355457][ T183] flags: 0x3ffff800000100(active|node=0|zone=0|lastcpupid=0x7ffff) [ 265.358719][ T183] raw: 003ffff800000100 0000000000000000 5deadbeef0000122 0000000000000000 [ 265.360177][ T183] raw: 0000000000000000 c0000000119caf58 00000000ffffffff 0000000000000000 [ 265.361438][ T183] page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set [ 265.362572][ T183] Modules linked in: [ 265.364622][ T183] CPU: 0 UID: 0 PID: 183 Comm: a.out Not tainted 6.18.0-rc3-00141-g1ddeaaace7ff-dirty #53 VOLUNTARY [ 265.364785][ T183] Hardware name: IBM pSeries (emulated by qemu) POWER10 (architected) 0x801200 0xf000006 of:SLOF,git-ee03ae pSeries [ 265.364908][ T183] Call Trace: [ 265.364955][ T183] [c000000011e6f7c0] [c000000001cfaa18] dump_stack_lvl+0x130/0x148 (unreliable) [ 265.365202][ T183] [c000000011e6f7f0] [c000000000794758] bad_page+0xb4/0x1c8 [ 265.365384][ T183] [c000000011e6f890] [c00000000079c020] __free_frozen_pages+0x838/0xd08 [ 265.365554][ T183] [c000000011e6f980] [c0000000000a70ac] pte_frag_destroy+0x298/0x310 [ 265.365729][ T183] [c000000011e6fa30] [c0000000000aa764] arch_exit_mmap+0x34/0x218 [ 265.365912][ T183] [c000000011e6fa80] [c000000000751698] exit_mmap+0xb8/0x820 [ 265.366080][ T183] [c000000011e6fc30] [c0000000001b1258] __mmput+0x98/0x300 [ 265.366244][ T183] [c000000011e6fc80] [c0000000001c81f8] do_exit+0x470/0x1508 [ 265.366421][ T183] [c000000011e6fd70] [c0000000001c95e4] do_group_exit+0x88/0x148 [ 265.366602][ T183] [c000000011e6fdc0] [c0000000001c96ec] pid_child_should_wake+0x0/0x178 [ 265.366780][ T183] [c000000011e6fdf0] [c00000000003a270] system_call_exception+0x1b0/0x4e0 [ 265.366958][ T183] [c000000011e6fe50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec The bad page state error occurs when such a folio gets freed (with active flag set), from do_exit() path in parallel. ... this can happen when the pte fragment was allocated from this folio, but when all the fragments get freed, the pte_frag_refcount still had some unused fragments. Now, if this process exits, with such folio as it's cached pte_frag in mm->context, then during pte_frag_destroy(), we simply call pagetable_dtor() and pagetable_free(), meaning it doesn't clear the active flag. This, can lead to the above bug. Since we are anyway in do_exit() path, then if the refcount is 0, then I guess it should be ok to simply clear the folio active flag before calling pagetable_dtor() & pagetable_free().

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-53089

bpf: Fix use-after-free in offloaded map/prog info fill

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix use-after-free in offloaded map/prog info fill When querying info for an offloaded BPF map or program, bpf_map_offload_info_fill_ns() and bpf_prog_offload_info_fill_ns() obtain the network namespace with get_net(dev_net(offmap->netdev)). However, the associated netdev's netns may be racing with teardown during netns destruction. If the netns refcount has already reached 0, get_net() performs a refcount_t increment on 0, triggering: refcount_t: addition on 0; use-after-free. Although rtnl_lock and bpf_devs_lock ensure the netdev pointer remains valid, they cannot prevent the netns refcount from reaching zero. Fix this by using maybe_get_net() instead of get_net(). maybe_get_net() uses refcount_inc_not_zero() and returns NULL if the refcount is already zero, which causes ns_get_path_cb() to fail and the caller to return -ENOENT -- the correct behavior when the netns is being destroyed.

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-46252

regulator: core: fix locking in regulator_resolve_supply() error path

In the Linux kernel, the following vulnerability has been resolved: regulator: core: fix locking in regulator_resolve_supply() error path If late enabling of a supply regulator fails in regulator_resolve_supply(), the code currently triggers a lockdep warning: WARNING: drivers/regulator/core.c:2649 at _regulator_put+0x80/0xa0, CPU#6: kworker/u32:4/596 ... Call trace: _regulator_put+0x80/0xa0 (P) regulator_resolve_supply+0x7cc/0xbe0 regulator_register_resolve_supply+0x28/0xb8 as the regulator_list_mutex must be held when calling _regulator_put(). To solve this, simply switch to using regulator_put(). While at it, we should also make sure that no concurrent access happens to our rdev while we clear out the supply pointer. Add appropriate locking to ensure that. While the code in question will be removed altogether in a follow-up commit, I believe it is still beneficial to have this corrected before removal for future reference.

CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed

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CVE-2026-46189

RDMA/vmw_pvrdma: Fix double free on pvrdma_alloc_ucontext() error path

In the Linux kernel, the following vulnerability has been resolved: RDMA/vmw_pvrdma: Fix double free on pvrdma_alloc_ucontext() error path Sashiko points out that pvrdma_uar_free() is already called within pvrdma_dealloc_ucontext(), so calling it before triggers a double free.

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-46180

wifi: brcmfmac: Fix potential use-after-free issue when stopping watchdog task

In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: Fix potential use-after-free issue when stopping watchdog task Watchdog task might end between send_sig() and kthread_stop() calls, what results in the use-after-free issue. Fix this by increasing watchdog task reference count before calling send_sig() and dropping it by switching to kthread_stop_put().

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-46162

ice: fix double free in ice_sf_eth_activate() error path

In the Linux kernel, the following vulnerability has been resolved: ice: fix double free in ice_sf_eth_activate() error path When auxiliary_device_add() fails, ice_sf_eth_activate() jumps to aux_dev_uninit and calls auxiliary_device_uninit(&sf_dev->adev). The device release callback ice_sf_dev_release() frees sf_dev, but the current error path falls through to sf_dev_free and calls kfree(sf_dev) again, causing a double free. Keep kfree(sf_dev) for the auxiliary_device_init() failure path, but avoid falling through to sf_dev_free after auxiliary_device_uninit().

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-46121

mm/damon/sysfs-schemes: protect memcg_path kfree() with damon_sysfs_lock

In the Linux kernel, the following vulnerability has been resolved: mm/damon/sysfs-schemes: protect memcg_path kfree() with damon_sysfs_lock Patch series "mm/damon/sysfs-schemes: fix use-after-free for [memcg_]path". Reads of 'memcg_path' and 'path' files in DAMON sysfs interface could race with their writes, results in use-after-free. Fix those. This patch (of 2): damon_sysfs_scheme_filter->mmecg_path can be read and written by users, via DAMON sysfs memcg_path file. It can also be indirectly read, for the parameters {on,off}line committing to DAMON. The reads for parameters committing are protected by damon_sysfs_lock to avoid the sysfs files being destroyed while any of the parameters are being read. But the user-driven direct reads and writes are not protected by any lock, while the write is deallocating the memcg_path-pointing buffer. As a result, the readers could read the already freed buffer (user-after-free). Note that the user-reads don't race when the same open file is used by the writer, due to kernfs's open file locking. Nonetheless, doing the reads and writes with separate open files would be common. Fix it by protecting both the user-direct reads and writes with damon_sysfs_lock.

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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CVE-2026-46084

RDMA/mana_ib: Disable RX steering on RSS QP destroy

In the Linux kernel, the following vulnerability has been resolved: RDMA/mana_ib: Disable RX steering on RSS QP destroy When an RSS QP is destroyed (e.g. DPDK exit), mana_ib_destroy_qp_rss() destroys the RX WQ objects but does not disable vPort RX steering in firmware. This leaves stale steering configuration that still points to the destroyed RX objects. If traffic continues to arrive (e.g. peer VM is still transmitting) and the VF interface is subsequently brought up (mana_open), the firmware may deliver completions using stale CQ IDs from the old RX objects. These CQ IDs can be reused by the ethernet driver for new TX CQs, causing RX completions to land on TX CQs: WARNING: mana_poll_tx_cq+0x1b8/0x220 [mana] (is_sq == false) WARNING: mana_gd_process_eq_events+0x209/0x290 (cq_table lookup fails) Fix this by disabling vPort RX steering before destroying RX WQ objects. Note that mana_fence_rqs() cannot be used here because the fence completion is delivered on the CQ, which is polled by user-mode (e.g. DPDK) and not visible to the kernel driver. Refactor the disable logic into a shared mana_disable_vport_rx() in mana_en, exported for use by mana_ib, replacing the duplicate code. The ethernet driver's mana_dealloc_queues() is also updated to call this common function.

CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed

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