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In the Linux kernel, the following vulnerability has been resolved: x86/mm: Don't apply va_align to hugetlb mappings on AMD F15h get_align_mask() returns huge_page_mask_align() for hugetlbfs, but get_align_bits() adds va_align.bits regardless, so vm_unmapped_area() returns an address off the huge page boundary and __unmap_hugepage_range() hits BUG_ON(start & ~huge_page_mask(h)) at teardown. This can be triggered on Carrizo and FX-8370E, both hstates. Pass the file to get_align_bits() and skip the randomisation …

In the Linux kernel, the following vulnerability has been resolved: tpm: fix off-by-four bounds check in tpm2_get_random() When the response carries the TPM2_ST_SESSIONS tag, tpm2_get_random() skips the 4-byte parameter size field before locating the random data, but the bounds check still validates the response length against TPM_HEADER_SIZE. A truncated response can pass the check and make memcpy() read up to 4 bytes past the response end, so stale buffer contents end up in the caller's random bytes. Fix this…

In the Linux kernel, the following vulnerability has been resolved: nvme-multipath: set BLK_FEAT_ZONED only after the zone info is known The namespace head is marked zoned at allocation time based only on the command set identifier. If the zone info query reports a zero zone size, the path namespace is registered without zoned limits while the head still advertises the zoned capability with a zone size of zero, and reporting zones or writing to the head then shifts by ilog2(0). Drop the zoned feature from the h…

In the Linux kernel, the following vulnerability has been resolved: nvme-multipath: fix underflow in ANA log bounds checks The number of ANA groups advertised through Identify Controller sizes the ANA log buffer. The ANA log header and group descriptors independently supply the number of groups and namespace IDs to parse. Both bounds checks subtract an untrusted object size from ana_log_size before comparing the current offset. If the object is larger than the buffer, the size_t subtraction underflows and lets t…

In the Linux kernel, the following vulnerability has been resolved: nvmet-auth: fix out-of-bounds write in nvmet_auth_challenge() nvmet_auth_challenge() receives its output buffer as a void pointer. sizeof(*d) therefore evaluates to one with GCC and undercounts the fixed challenge header by 15 bytes. A short AUTH_RECEIVE buffer can pass the check before the challenge is copied past the end of its allocation. Use the typed challenge pointer when calculating the response size. BUG: KASAN: slab-out-of-bounds in…

In the Linux kernel, the following vulnerability has been resolved: nvmet: pci-epf: reject too-short SGL segments The host controls an SGL segment's length. A nonzero length smaller than one SGL descriptor makes nr_descs zero, so nvmet_pci_epf_get_sgl_segment() reads the type byte of sgls[-1] outside the allocated buffer. If that byte contains a segment descriptor type, the function also copies the preceding 16 bytes and returns a negative descriptor count. The read was reproduced in 3/3 KASAN boots with only th…

In the Linux kernel, the following vulnerability has been resolved: nvmet: copy the hostid into the ctrl before creating PR pc_refs Commit 6202783184bf ("nvmet: Improve nvmet_alloc_ctrl() interface and implementation") added a second uuid_copy() of args->hostid near the end of nvmet_alloc_ctrl(), and commit 7b658153f1b8 ("nvmet: Remove duplicate uuid_copy") removed the original copy that sat before nvmet_ctrl_init_pr() instead of the new one. Since then nvmet_ctrl_init_pr() snapshots ctrl->hostid into the per-co…

In the Linux kernel, the following vulnerability has been resolved: mtd: block2mtd: Fix divide error when erase_size is zero The erase size is parsed from the "block2mtd" module parameter and can be set to zero. add_device() then evaluates if (size % erase_size) with a zero divisor, which triggers a divide error: divide error: 0000 [#1] PREEMPT SMP PTI RIP: 0010:add_device drivers/mtd/devices/block2mtd.c:296 [inline] RIP: 0010:block2mtd_setup2+0x592/0xda0 drivers/mtd/devices/block2mtd.c:459 Call Trace:…

In the Linux kernel, the following vulnerability has been resolved: mtd: rawnand: cadence: Initialize IRQ state before requesting IRQ The Cadence NAND interrupt handler uses both the IRQ lock and completion object. Registering the IRQ before initializing them leaves a window in which a pending interrupt can access uninitialized synchronization state. Initialize them before registering the handler.

In the Linux kernel, the following vulnerability has been resolved: KVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified Force a refresh of the vmcs02 MSR bitmap during nested VM-Enter if the runtime eVMCS controls (pin, primary, secondary, etc.) are being updated. If L1 isn't intercepting TPR writes, runs L2 with TPR virtualization, and then runs the same L2 with TPR virtualization disabled, KVM will fail to refresh msr_bitmap02 and leave TPR in passthrough mode even though TPR virtualizati…

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…