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In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Nullify "have run CPUs" mask pointer when freeing it Nullify have_run_cpus when freeing the mask, particularly in the error path of __sev_guest_init(), so that KVM doesn't have to subtly use sev->active to track whether or not the mask has been freed. As pointed out by Sashiko, blindly freeing the mask in sev_vm_destroy() results in a double-free if the mask is freed if __sev_guest_init() fails. Throw the logic in a helper as nullifyi…

In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Do cache maintenance on the source VM *before* clearing SEV state Explicitly flush caches after intra-host migration before clearing "SEV active" on the source VM, as doing cache maintenance afterwards creates a tiny window where memory reclaim could return memory to the host without performing a cache flush, e.g. as pointed out by Sashiko: CPU1 in sev_migrate_from(): src->active = false; CPU2 running concurrent unmap: Sin…

In the Linux kernel, the following vulnerability has been resolved: KVM: x86/mmu: Bail from shadow walks if the root is invalid or a dummy When walking shadow page tables, immediately terminate the walk if the root is a "dummy" root, i.e. a root whose top-level page table is backed by the zero page, but otherwise doesn't exist. If memslot creation races with a stage-2 page fault (EPT violation or #NPF) from L2, then if the stars align, KVM will attempt to walk shadow page tables using the zero page and hit a NUL…

In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Use the active VMCB's MSR bitmap when checking if MSR is intercepted Use the MSR permission bitmap of the active VMCB instead of assuming that KVM is always using vmcb02's bitmap when L2 is active, as KVM uses msrpm02 if and only if L1 wants to intercept MSR accesses, i.e. if and only if KVM needs to merge msprm01 with msrpm12. Don't bother tracking the virtual address of the bitmap that's being used, as __va() is cheap on x86, and cac…

In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Preserve TLB control (i.e. pending TLB flush) on failed VMRUN Don't reset the VMCB's TLB control back to "do nothing" on a failed VMRUN, as empirical testing shows that the CPU performs the requested TLB flush if and only if VMRUN is successful, i.e. clearing TLB control on a failed VMRUN effectively drops a TLB flush. Explicitly track the need to flush all ASIDs on a per-CPU basis, as the ASID reuse condition is tied to the pCPU, not …

In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Update control fields on #VMEXIT if and only if VMRUN succeeded Leave control.erap_ctl and control.clean as-is in the VMCS if VMRUN fails, because as per AMD: there's no explicit architectural guarantee about the behavior in the presence of VMRUN failures. So the best thing to do would be to assume that if VMRUN fails, the actions requested in the control fields may not have been performed.

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Apply the fine-grained UNDEFs without FEAT_FGT FGUs don't actually require hardware support, so don't gate fgt trap config insertion on FGT. This is the only action required to allow FGUs always, as kvm_calculate_traps() already computes the FGU bits with or without FEAT_FGT. This also fixes a spurious WARN when a TLBI OS is run on a guest in vEL1 without FEAT_TLBIOS on non FEAT_FGT hardware. In this configuration the course-grained …

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic: Take a refcount on IRQs referenced by last_lr_irq Referencing the last interrupt inserted in an LR is rather fragile, as this interrupt can vanish if a concurrently unmapped LPI. Solve this by bumping up the refcount on the interrupt when populating last_lr_irq, and drop it at vgic_prune_ap_list() time, when LPIs are being reclaimed.

In the Linux kernel, the following vulnerability has been resolved: wifi: cw1200: fix TX padding OOB read leaking heap data to device The TX path rounds the transfer size up to the bus alignment (align_size(), up to 511 bytes for SDIO, 1 byte for SPI) but sends the padded length straight from the frame buffer, which has no room reserved for the padding. cw1200_data_write() therefore reads past the end of the frame and the bus transfer carries those bytes to the device. A bogus device can collect up to 511 bytes…

In the Linux kernel, the following vulnerability has been resolved: wifi: iwlegacy: 3945: free EEPROM data on remove il3945_pci_probe() calls il_eeprom_init(), which allocates memory for the EEPROM data. The probe failure paths release this allocation with il_eeprom_free(), but the remove path does not free it after a successful probe. As a result, the EEPROM data is leaked when the PCI device is removed. Free the EEPROM data in il3945_pci_remove() before releasing the mac80211 hardware structure. This issue w…

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: count only matching reservations in reserved switch ieee80211_vif_use_reserved_switch() validates a replacement by counting assigned links on ctx->replace_ctx and treating reservations too broadly. A link can still be assigned to the old channel context while holding a reservation that belongs to a different replacement operation. That can make the current replacement appear complete too early. If another link finalizes first, th…

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: keep paired old chanctx alive An in-place replacement keeps reciprocal replace_ctx pointers between the old WILL_BE_REPLACED chanctx and the new REPLACES_OTHER chanctx. However, the early free paths only consider assigned and reserved link users when deciding whether to free the old chanctx. That lets the old chanctx be freed too early while the replacement partner still points back to it, either when the last assigned link is re…

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: shut down RX BA session timer on teardown Tearing down an RX BA session can leave the session timer queued on a freed tid_rx. Later timer-wheel processing and the timer callback itself then run against freed memory. An RX BAR handler can dereference tid_rx under RCU before teardown unpublishes it and stay in its read-side critical section while teardown deletes the session timer. The stale handler can then rearm the timer after t…

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: drain PS delivery work during station teardown Removing an AP or mesh station can notify the driver and wake TXQs after the station has already been removed from the driver, and can update num_sta_ps and the power-save queues after station cleanup has purged them. sta_deliver_ps_frames() tests sta->dead only before it starts delivery. A worker that passes that test can be delayed while teardown sets sta->dead and removes the stat…

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: account proxy paths against the mesh path limit Proxy-path churn can drive the interface path counter negative and let later mesh path additions exceed MESH_MAX_MPATHS. mesh_path_free_rcu() decrements the interface mpaths counter for entries from both the mesh and proxy path tables, but mpp_path_add() never reserves a slot in that counter. Removing or expiring a proxy path therefore returns a slot that was never charged. mesh_pa…

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: keep fallback association elements alive Associating to a non-transmitted MBSSID profile reads freed memory while determining the operating channel and applying HT capabilities. When an association response omits WMM, HT, or VHT information, ieee80211_assoc_config_link() parses the cached BSS IEs and copies the missing element pointers out of that fallback parse. For a non-transmitted MBSSID profile those pointers refer to merged…

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: minstrel_ht: validate fixed rate index The fixed_rate_idx debugfs file is a plain u32 attribute, so any value can be written to it. minstrel_ht_update_stats() then copies the value into mi->max_tp_rate[] and mi->max_prob_rate, and minstrel_ht_set_rate() uses MI_RATE_GROUP()/MI_RATE_IDX() to index minstrel_mcs_groups[] (42 entries) and mi->groups[].rates[] (10 entries) with it. Writing e.g. 65535 selects group 4095 and rate index…

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: reject invalid 320 MHz CSA bandwidth The HT/VHT channel definition validator can receive a 320 MHz bandwidth indication from a received CSA frame on a non-6 GHz link. It warns for this unsupported width but continues with an uninitialized vht_operation.chan_width, which is then read by ieee80211_chandef_vht_oper(). With panic_on_warn enabled, this lets a received frame panic the kernel. Reject the channel definition before enteri…

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: release mesh path quota on failed additions Repeated failed or duplicate mesh path additions can exhaust MESH_MAX_MPATHS while the path table holds fewer paths, which stops new paths to reachable destinations from being created. mesh_path_add() reserves a slot before allocating and inserting a path. If allocation fails, the function returns without releasing the slot. If the rhashtable insertion reports an error or an existing de…

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: set info->band for 802.3 encap offload frames Unlike the 802.11 TX paths, ieee80211_8023_xmit() does not set info->band from the channel context on non-MLD interfaces. It stays at 0, so ieee80211_get_tx_rates() uses the wrong band for these frames. Set it the same way as ieee80211_build_hdr(): drop the frame if there is no channel context, and leave the band at 0 on MLD interfaces.

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: fix mesh fast xmit path deletion UAF mesh_fast_tx_cache() stores raw mesh_path pointers. Path deletion flushes the cache and then frees the path with kfree_rcu(), but a lookup that already holds the path can insert a new cache entry after the flush. The cache then points at freed memory. Set MESH_PATH_DELETED before flushing, and skip inserting a cache entry if the path or MPP path is already deleted. Check this under the cache w…

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: handle empty FILS association request payload fils_encrypt_assoc_req() accepts a (Re)Association Request frame whose last element is the FILS Session element. crypt_len is then zero and aes_siv_encrypt() is called with an empty plaintext. kmemdup() returns ZERO_SIZE_PTR for a zero-length allocation, so the unconditional sg_init_one() puts an invalid page into the scatterlist. With CONFIG_DEBUG_SG this triggers a kernel BUG in sg…

In the Linux kernel, the following vulnerability has been resolved: USB: serial: fix dynamic id driver deregistration race Only free the dynamic ids after having deregistered the driver and removed the "new_id" attribute to avoid leaking any id added by a racing write to the attribute.

In the Linux kernel, the following vulnerability has been resolved: USB: serial: fix driver deregistration order USB serial driver modules register one driver for the USB bus and one or more drivers for the ports on the USB serial bus. When unloading a driver module, the USB driver must be deregistered before the USB serial bus drivers so that I/O is stopped before unbinding the ports to avoid use-after-free in completion handlers accessing port data. Note that the "new_id" attributes must first be removed to p…

In the Linux kernel, the following vulnerability has been resolved: USB: serial: fix ioctl hangup race The tty ioctls can race with hangup and end up calling into a tty driver for a device that is already gone or powered down. Serialise the callbacks using the tty port mutex and add the missing checks to make sure the port has not been hung up before accessing port driver data or hardware. This specifically avoids dereferencing a NULL-pointer if a device is disconnected during lengthy break signalling. Note th…