Linux Linux Kernel vulnerabilities

In the Linux kernel, the following vulnerability has been resolved: media: iris: gen1: Destroy internal buffers after FW releases After the firmware releases internal buffers, the driver was not destroying them. This left stale allocations that were no longer used, especially across resolution changes where new buffers are allocated per the updated requirements. As a result, memory was wasted until session close. Destroy internal buffers once the release response is received from the firmware.

In the Linux kernel, the following vulnerability has been resolved: HID: magicmouse: Do not crash on missing msc->input Fake USB devices can send their own report descriptors for which the input_mapping() hook does not get called. In this case, msc->input stays NULL, leading to a crash at a later time. Detect this condition in the input_configured() hook and reject the device. This is not supposed to happen with actual magic mouse devices, but can be provoked by imposing as a magic mouse USB device.

In the Linux kernel, the following vulnerability has been resolved: ASoC: SOF: Intel: hda: Fix NULL pointer dereference If there's a mismatch between the DAI links in the machine driver and the topology, it is possible that the playback/capture widget is not set, especially in the case of loopback capture for echo reference where we use the dummy DAI link. Return the error when the widget is not set to avoid a null pointer dereference like below when the topology is broken. RIP: 0010:hda_dai_get_ops.isra.0+0x14/0xa0 [snd_sof_intel_hda_common]

In the Linux kernel, the following vulnerability has been resolved: HID: logitech-hidpp: Check maxfield in hidpp_get_report_length() Do not crash when a report has no fields. Fake USB gadgets can send their own HID report descriptors and can define report structures without valid fields. This can be used to crash the kernel over USB.

In the Linux kernel, the following vulnerability has been resolved: media: cx23885: Add missing unmap in snd_cx23885_hw_params() In error path, add cx23885_alsa_dma_unmap() to release the resource acquired by cx23885_alsa_dma_map().

In the Linux kernel, the following vulnerability has been resolved: dm-verity: correctly handle dm_bufio_client_create() failure If either of the calls to dm_bufio_client_create() in verity_fec_ctr() fails, then dm_bufio_client_destroy() is later called with an ERR_PTR() argument. That causes a crash. Fix this.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/pm: Fix null pointer dereference issue If SMU is disabled, during RAS initialization, there will be null pointer dereference issue here.

In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Flush dev-IOTLB only when PCIe device is accessible in scalable mode Commit 4fc82cd907ac ("iommu/vt-d: Don't issue ATS Invalidation request when device is disconnected") relies on pci_dev_is_disconnected() to skip ATS invalidation for safely-removed devices, but it does not cover link-down caused by faults, which can still hard-lock the system. For example, if a VM fails to connect to the PCIe device, "virsh destroy" is executed to release resources and isolate the fault, but a hard-lockup occurs while releasing the group fd. Call Trace: qi_submit_sync qi_flush_dev_iotlb intel_pasid_tear_down_entry device_block_translation blocking_domain_attach_dev __iommu_attach_device __iommu_device_set_domain __iommu_group_set_domain_internal iommu_detach_group vfio_iommu_type1_detach_group vfio_group_detach_container vfio_group_fops_release __fput Although pci_device_is_present() is slower than pci_dev_is_disconnected(), it still takes only ~70 µs on a ConnectX-5 (8 GT/s, x2) and becomes even faster as PCIe speed and width increase. Besides, devtlb_invalidation_with_pasid() is called only in the paths below, which are far less frequent than memory map/unmap. 1. mm-struct release 2. {attach,release}_dev 3. set/remove PASID 4. dirty-tracking setup The gain in system stability far outweighs the negligible cost of using pci_device_is_present() instead of pci_dev_is_disconnected() to decide when to skip ATS invalidation, especially under GDR high-load conditions.

In the Linux kernel, the following vulnerability has been resolved: ima: verify the previous kernel's IMA buffer lies in addressable RAM Patch series "Address page fault in ima_restore_measurement_list()", v3. When the second-stage kernel is booted via kexec with a limiting command line such as "mem=<size>" we observe a pafe fault that happens. BUG: unable to handle page fault for address: ffff97793ff47000 RIP: ima_restore_measurement_list+0xdc/0x45a #PF: error_code(0x0000) not-present page This happens on x86_64 only, as this is already fixed in aarch64 in commit: cbf9c4b9617b ("of: check previous kernel's ima-kexec-buffer against memory bounds") This patch (of 3): When the second-stage kernel is booted with a limiting command line (e.g. "mem=<size>"), the IMA measurement buffer handed over from the previous kernel may fall outside the addressable RAM of the new kernel. Accessing such a buffer can fault during early restore. Introduce a small generic helper, ima_validate_range(), which verifies that a physical [start, end] range for the previous-kernel IMA buffer lies within addressable memory: - On x86, use pfn_range_is_mapped(). - On OF based architectures, use page_is_ram().

In the Linux kernel, the following vulnerability has been resolved: ntfs3: fix circular locking dependency in run_unpack_ex Syzbot reported a circular locking dependency between wnd->rw_lock (sbi->used.bitmap) and ni->file.run_lock. The deadlock scenario: 1. ntfs_extend_mft() takes ni->file.run_lock then wnd->rw_lock. 2. run_unpack_ex() takes wnd->rw_lock then tries to acquire ni->file.run_lock inside ntfs_refresh_zone(). This creates an AB-BA deadlock. Fix this by using down_read_trylock() instead of down_read() when acquiring run_lock in run_unpack_ex(). If the lock is contended, skip ntfs_refresh_zone() - the MFT zone will be refreshed on the next MFT operation. This breaks the circular dependency since we never block waiting for run_lock while holding wnd->rw_lock.

In the Linux kernel, the following vulnerability has been resolved: pstore: ram_core: fix incorrect success return when vmap() fails In persistent_ram_vmap(), vmap() may return NULL on failure. If offset is non-zero, adding offset_in_page(start) causes the function to return a non-NULL pointer even though the mapping failed. persistent_ram_buffer_map() therefore incorrectly returns success. Subsequent access to prz->buffer may dereference an invalid address and cause crashes. Add proper NULL checking for vmap() failures.

In the Linux kernel, the following vulnerability has been resolved: fbcon: check return value of con2fb_acquire_newinfo() If fbcon_open() fails when called from con2fb_acquire_newinfo() then info->fbcon_par pointer remains NULL which is later dereferenced. Add check for return value of the function con2fb_acquire_newinfo() to avoid it. Found by Linux Verification Center (linuxtesting.org) with SVACE.

In the Linux kernel, the following vulnerability has been resolved: io_uring/zcrx: fix user_ref race between scrub and refill paths The io_zcrx_put_niov_uref() function uses a non-atomic check-then-decrement pattern (atomic_read followed by separate atomic_dec) to manipulate user_refs. This is serialized against other callers by rq_lock, but io_zcrx_scrub() modifies the same counter with atomic_xchg() WITHOUT holding rq_lock. On SMP systems, the following race exists: CPU0 (refill, holds rq_lock) CPU1 (scrub, no rq_lock) put_niov_uref: atomic_read(uref) - 1 // window opens atomic_xchg(uref, 0) - 1 return_niov_freelist(niov) [PUSH #1] // window closes atomic_dec(uref) - wraps to -1 returns true return_niov(niov) return_niov_freelist(niov) [PUSH #2: DOUBLE-FREE] The same niov is pushed to the freelist twice, causing free_count to exceed nr_iovs. Subsequent freelist pushes then perform an out-of-bounds write (a u32 value) past the kvmalloc'd freelist array into the adjacent slab object. Fix this by replacing the non-atomic read-then-dec in io_zcrx_put_niov_uref() with an atomic_try_cmpxchg loop that atomically tests and decrements user_refs. This makes the operation safe against concurrent atomic_xchg from scrub without requiring scrub to acquire rq_lock. [pavel: removed a warning and a comment]

In the Linux kernel, the following vulnerability has been resolved: fs/buffer: add alert in try_to_free_buffers() for folios without buffers try_to_free_buffers() can be called on folios with no buffers attached when filemap_release_folio() is invoked on a folio belonging to a mapping with AS_RELEASE_ALWAYS set but no release_folio operation defined. In such cases, folio_needs_release() returns true because of the AS_RELEASE_ALWAYS flag, but the folio has no private buffer data. This causes try_to_free_buffers() to call drop_buffers() on a folio with no buffers, leading to a null pointer dereference. Adding a check in try_to_free_buffers() to return early if the folio has no buffers attached, with WARN_ON_ONCE() to alert about the misconfiguration. This provides defensive hardening.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix NULL pointer issue buffer funcs If SDMA block not enabled, buffer_funcs will not initialize, fix the null pointer issue if buffer_funcs not initialized.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/ras: Move ras data alloc before bad page check In the rare event if eeprom has only invalid address entries, allocation is skipped, this causes following NULL pointer issue [ 547.103445] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 547.118897] #PF: supervisor read access in kernel mode [ 547.130292] #PF: error_code(0x0000) - not-present page [ 547.141689] PGD 124757067 P4D 0 [ 547.148842] Oops: 0000 [#1] PREEMPT SMP NOPTI [ 547.158504] CPU: 49 PID: 8167 Comm: cat Tainted: G OE 6.8.0-38-generic #38-Ubuntu [ 547.177998] Hardware name: Supermicro AS -8126GS-TNMR/H14DSG-OD, BIOS 1.7 09/12/2025 [ 547.195178] RIP: 0010:amdgpu_ras_sysfs_badpages_read+0x2f2/0x5d0 [amdgpu] [ 547.210375] Code: e8 63 78 82 c0 45 31 d2 45 3b 75 08 48 8b 45 a0 73 44 44 89 f1 48 8b 7d 88 48 89 ca 48 c1 e2 05 48 29 ca 49 8b 4d 00 48 01 d1 <48> 83 79 10 00 74 17 49 63 f2 48 8b 49 08 41 83 c2 01 48 8d 34 76 [ 547.252045] RSP: 0018:ffa0000067287ac0 EFLAGS: 00010246 [ 547.263636] RAX: ff11000167c28130 RBX: ff11000127600000 RCX: 0000000000000000 [ 547.279467] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ff11000125b1c800 [ 547.295298] RBP: ffa0000067287b50 R08: 0000000000000000 R09: 0000000000000000 [ 547.311129] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 547.326959] R13: ff11000217b1de00 R14: 0000000000000000 R15: 0000000000000092 [ 547.342790] FS: 0000746e59d14740(0000) GS:ff11017dfda80000(0000) knlGS:0000000000000000 [ 547.360744] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 547.373489] CR2: 0000000000000010 CR3: 000000019585e001 CR4: 0000000000f71ef0 [ 547.389321] PKRU: 55555554 [ 547.395316] Call Trace: [ 547.400737] <TASK> [ 547.405386] ? show_regs+0x6d/0x80 [ 547.412929] ? __die+0x24/0x80 [ 547.419697] ? page_fault_oops+0x99/0x1b0 [ 547.428588] ? do_user_addr_fault+0x2ee/0x6b0 [ 547.438249] ? exc_page_fault+0x83/0x1b0 [ 547.446949] ? asm_exc_page_fault+0x27/0x30 [ 547.456225] ? amdgpu_ras_sysfs_badpages_read+0x2f2/0x5d0 [amdgpu] [ 547.470040] ? mas_wr_modify+0xcd/0x140 [ 547.478548] sysfs_kf_bin_read+0x63/0xb0 [ 547.487248] kernfs_file_read_iter+0xa1/0x190 [ 547.496909] kernfs_fop_read_iter+0x25/0x40 [ 547.506182] vfs_read+0x255/0x390 This also result in space left assigned to negative values. Moving data alloc call before bad page check resolves both the issue.

In the Linux kernel, the following vulnerability has been resolved: jfs: nlink overflow in jfs_rename If nlink is maximal for a directory (-1) and inside that directory you perform a rename for some child directory (not moving from the parent), then the nlink of the first directory is first incremented and later decremented. Normally this is fine, but when nlink = -1 this causes a wrap around to 0, and then drop_nlink issues a warning. After applying the patch syzbot no longer issues any warnings. I also ran some basic fs tests to look for any regressions.