kernel/linux.git/drivers/dma-buf/dma-buf.c, branch linux-7.1.y

dma-buf: fix UAF in dma_buf_fd() tracepoint

2026-05-28T14:35:43+00:00

Once FD_ADD() returns, the fd is live in the file descriptor table and a thread sharing that table can close() it before DMA_BUF_TRACE() runs. The close drops the last reference, __fput() frees the dma_buf, and the tracepoint then dereferences dmabuf to take dmabuf->name_lock -- slab-use-after-free. Split FD_ADD() back into get_unused_fd_flags() + fd_install() and emit the tracepoint between them. While the fdtable slot is reserved with a NULL file pointer, a racing close() returns -EBADF without entering __fput(), so the dma_buf stays alive across the trace. Same approach as commit 2d76319c4cbb ("dma-buf: fix UAF in dma_buf_put() tracepoint"). This undoes the FD_ADD() conversion done in commit 34dfce523c90 ("dma: convert dma_buf_fd() to FD_ADD()"); FD_ADD() has no place to hook the tracepoint safely. Reported-by: syzbot+7f4987d0afb97dd090cb@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=7f4987d0afb97dd090cb Fixes: 281a22631423 ("dma-buf: add some tracepoints to debug.") Cc: stable@vger.kernel.org # 7.0.x Signed-off-by: David Carlier Reviewed-by: Christian König Signed-off-by: Sumit Semwal Link: https://patch.msgid.link/20260523181446.69525-1-devnexen@gmail.com

Merge tag 'drm-fixes-2026-04-24' of https://gitlab.freedesktop.org/drm/kernel

2026-04-24T18:44:52+00:00

Pull more drm fixes from Dave Airlie: "These are the regular fixes that have built up over last couple of weeks, all pretty minor and spread all over. atomic: - raise the vblank timeout to avoid it on virtual drivers - fix colorop duplication bridge: - stm_lvds: state check fix - dw-mipi-dsi: bridge reference leak fix panel: - visionx-rm69299: init fix dma-fence: - fix sparse warning dma-buf: - UAF fix panthor: - mapping fix arcgpu: - device_node reference leak fix nouveau: - memory leak in error path fix - overflow in reloc path for old hw fix hv: - Kconfig fix v3d: - infinite loop fix" * tag 'drm-fixes-2026-04-24' of https://gitlab.freedesktop.org/drm/kernel: drm/nouveau: fix u32 overflow in pushbuf reloc bounds check MAINTAINERS: split hisilicon maintenance and add Yongbang Shi for hibmc-drm matainers drm/v3d: Reject empty multisync extension to prevent infinite loop drm/panel: visionox-rm69299: Make use of prepare_prev_first drm/drm_atomic: duplicate colorop states if plane color pipeline in use drm/nouveau: fix nvkm_device leak on aperture removal failure hv: Select CONFIG_SYSFB only for CONFIG_HYPERV_VMBUS dma-fence: Silence sparse warning in dma_fence_describe drm/bridge: dw-mipi-dsi: Fix bridge leak when host attach fails drm/arcpgu: fix device node leak drm/panthor: Fix outdated function documentation drm/panthor: Extend VM locked region for remap case to be a superset dma-buf: fix UAF in dma_buf_put() tracepoint drm/bridge: stm_lvds: Do not fail atomic_check on disabled connector drm/atomic: Increase timeout in drm_atomic_helper_wait_for_vblanks()

Merge tag 'drm-next-2026-04-22' of https://gitlab.freedesktop.org/drm/kernel

2026-04-22T00:39:21+00:00

Pull more drm updates from Dave Airlie: "This is a followup which is mostly next material with some fixes. Alex pointed out I missed one of his AMD MRs from last week, so I added that, then Jani sent the pipe reordering stuff, otherwise it's just some minor i915 fixes and a dma-buf fix. drm: - Add support for AMD VSDB parsing to drm_edid dma-buf: - fix documentation formatting i915: - add support for reordered pipes to support joined pipes better - Fix VESA backlight possible check condition - Verify the correct plane DDB entry amdgpu: - Audio regression fix - Use drm edid parser for AMD VSDB - Misc cleanups - VCE cs parse fixes - VCN cs parse fixes - RAS fixes - Clean up and unify vram reservation handling - GPU Partition updates - system_wq cleanups - Add CONFIG_GCOV_PROFILE_AMDGPU kconfig option - SMU vram copy updates - SMU 13/14/15 fixes - UserQ fixes - Replace pasid idr with an xarray - Dither handling fix - Enable amdgpu by default for CIK APUs - Add IBs to devcoredump amdkfd: - system_wq cleanups radeon: - system_wq cleanups" * tag 'drm-next-2026-04-22' of https://gitlab.freedesktop.org/drm/kernel: (62 commits) drm/i915/display: change pipe allocation order for discrete platforms drm/i915/wm: Verify the correct plane DDB entry drm/i915/backlight: Fix VESA backlight possible check condition drm/i915: Walk crtcs in pipe order drm/i915/joiner: Make joiner "nomodeset" state copy independent of pipe order dma-buf: fix htmldocs error for dma_buf_attach_revocable drm/amdgpu: dump job ibs in the devcoredump drm/amdgpu: store ib info for devcoredump drm/amdgpu: extract amdgpu_vm_lock_by_pasid from amdgpu_vm_handle_fault drm/amdgpu: Use amdgpu by default for CIK APUs too drm/amd/display: Remove unused NUM_ELEMENTS macros drm/amd/display: Replace inline NUM_ELEMENTS macro with ARRAY_SIZE drm/amdgpu: save ring content before resetting the device drm/amdgpu: make userq fence_drv drop explicit in queue destroy drm/amdgpu: rework userq fence driver alloc/destroy drm/amdgpu/userq: use dma_fence_wait_timeout without test for signalled drm/amdgpu/userq: call dma_resv_wait_timeout without test for signalled drm/amdgpu/userq: add the return code too in error condition drm/amdgpu/userq: fence wait for max time in amdgpu_userq_wait_for_signal drm/amd/display: Change dither policy for 10 bpc output back to dithering ...

Merge tag 'drm-next-2026-04-15' of https://gitlab.freedesktop.org/drm/kernel

2026-04-15T15:45:00+00:00

Pull drm updates from Dave Airlie: "Highlights: - new DRM RAS infrastructure using netlink - amdgpu: enable DC on CIK APUs, and more IP enablement, and more user queue work - xe: purgeable BO support, and new hw enablement - dma-buf : add revocable operations Full summary: mm: - two-pass MMU interval notifiers - add gpu active/reclaim per-node stat counters math: - provide __KERNEL_DIV_ROUND_CLOSEST() in UAPI - implement DIV_ROUND_CLOSEST() with __KERNEL_DIV_ROUND_CLOSEST() rust: - shared tag with driver-core: register macro and io infra - core: rework DMA coherent API - core: add interop::list to interop with C linked lists - core: add more num::Bounded operations - core: enable generic_arg_infer and add EMSGSIZE - workqueue: add ARef support for work and delayed work - add GPU buddy allocator abstraction - add DRM shmem GEM helper abstraction - allow drm:::Device to dispatch work and delayed work items to driver private data - add dma_resv_lock helper and raw accessors core: - introduce DRM RAS infrastructure over netlink - add connector panel_type property - fourcc: add ARM interleaved 64k modifier - colorop: add destroy helper - suballoc: split into alloc and init helpers - mode: provide DRM_ARGB_GET*() macros for reading color components edid: - provide drm_output_color_Format dma-buf: - provide revoke mechanism for shared buffers - rename move_notify to invalidate_mappings - always enable move_notify - protect dma_fence_ops with RCU and improve locking - clean pages with helpers atomic: - allocate drm_private_state via callback - helper: use system_percpu_wq buddy: - make buddy allocator available to gpu level - add kernel-doc for buddy allocator - improve aligned allocation ttm: - fix fence signalling - improve tests and docs - improve handling of gfp_retry_mayfail - use per-node stat counters to track memory allocations - port pool to use list_lru - drop NUMA specific pools - make pool shrinker numa aware - track allocated pages per numa node coreboot: - cleanup coreboot framebuffer support sched: - fix race condition in drm_sched_fini pagemap: - enable THP support - pass pagemap_addr by reference gem-shmem: - Track page accessed/dirty status across mmap/vmap gpusvm: - reenable device to device migration - fix unbalanced unclock bridge: - anx7625: Support USB-C plus DT bindings - connector: Fix EDID detection - dw-hdmi-qp: Support Vendor-Specfic and SDP Infoframes; improve others - fsl-ldb: Fix visual artifacts plus related DT property 'enable-termination-resistor' - imx8qxp-pixel-link: Improve bridge reference handling - lt9611: Support Port-B-only input plus DT bindings - tda998x: Support DRM_BRIDGE_ATTACH_NO_CONNECTOR; Clean up - Support TH1520 HDMI plus DT bindings - waveshare-dsi: Fix register and attach; Support 1..4 DSI lanes plus DT bindings - anx7625: Fix USB Type-C handling - cdns-mhdp8546-core: Handle HDCP state in bridge atomic_check - Support Lontium LT8713SX DP MST bridge plus DT bindings - analogix_dp: Use DP helpers for link training panel: - panel-jdi-lt070me05000: Use mipi-dsi multi functions - panel-edp: Support Add AUO B116XAT04.1 (HW: 1A); Support CMN N116BCL-EAK (C2); Support FriendlyELEC plus DT changes - panel-edp: Fix timings for BOE NV140WUM-N64 - ilitek-ili9882t: Allow GPIO calls to sleep - jadard: Support TAIGUAN XTI05101-01A - lxd: Support LXD M9189A plus DT bindings - mantix: Fix pixel clock; Clean up - motorola: Support Motorola Atrix 4G and Droid X2 plus DT bindings - novatek: Support Novatek/Tianma NT37700F plus DT bindings - simple: Support EDT ET057023UDBA plus DT bindings; Support Powertip PH800480T032-ZHC19 plus DT bindings; Support Waveshare 13.3" - novatek-nt36672a: Use mipi_dsi_*_multi() functions - panel-edp: Support BOE NV153WUM-N42, CMN N153JCA-ELK, CSW MNF307QS3-2 - support Himax HX83121A plus DT bindings - support JuTouch JT070TM041 plus DT bindings - support Samsung S6E8FC0 plus DT bindings - himax-hx83102c: support Samsung S6E8FC0 plus DT bindings; support backlight - ili9806e: support Rocktech RK050HR345-CT106A plus DT bindings - simple: support Tianma TM050RDH03 plus DT bindings amdgpu: - enable DC by default on CIK APUs - userq fence ioctl param size fixes - set panel_type to OLED for eDP - refactor DC i2c code - FAMS2 update - rework ttm handling to allow multiple engines - DC DCE 6.x cleanup - DC support for NUTMEG/TRAVIS DP bridge - DCN 4.2 support - GC12 idle power fix for compute - use struct drm_edid in non-DC code - enable NV12/P010 support on primary planes - support newer IP discovery tables - VCN/JPEG 5.0.2 support - GC/MES 12.1 updates - USERQ fixes - add DC idle state manager - eDP DSC seamless boot amdkfd: - GC 12.1 updates - non 4K page fixes xe: - basic Xe3p_LPG and NVL-P enabling patches - allow VM_BIND decompress support - add purgeable buffer object support - add xe_vm_get_property_ioctl - restrict multi-lrc to VCS/VECS engines - allow disabling VM overcommit in fault mode - dGPU memory optimizations - Workaround cleanups and simplification - Allow VFs VRAM quote changes using sysfs - convert GT stats to per-cpu counters - pagefault refactors - enable multi-queue on xe3p_xpc - disable DCC on PTL - make MMIO communication more robust - disable D3Cold for BMG on specific platforms - vfio: improve FLR sync for Xe VFIO i915/display: - C10/C20/LT PHY PLL divider verification - use trans push mechanism to generate PSR frame change on LNL+ - refactor DP DSC slice config - VGA decode refactoring - refactor DPT, gen2-4 overlay, masked field register macro helpers - refactor stolen memory allocation decisions - prepare for UHBR DP tunnels - refactor LT PHY PLL to use DPLL framework - implement register polling/waiting in display code - add shared stepping header between i915 and display i915: - fix potential overflow of shmem scatterlist length nouveau: - provide Z cull info to userspace - initial GA100 support - shutdown on PCI device shutdown nova-core: - harden GSP command queue - add support for large RPCs - simplify GSP sequencer and message handling - refactor falcon firmware handling - convert to new register macro - conver to new DMA coherent API - use checked arithmetic - add debugfs support for gsp-rm log buffers - fix aux device registration for multi-GPU msm: - CI: - Uprev mesa - Restore CI jobs for Qualcomm APQ8016 and APQ8096 devices - Core: - Switched to of_get_available_child_by_name() - DPU: - Fixes for DSC panels - Fixed brownout because of the frequency / OPP mismatch - Quad pipe preparation (not enabled yet) - Switched to virtual planes by default - Dropped VBIF_NRT support - Added support for Eliza platform - Reworked alpha handling - Switched to correct CWB definitions on Eliza - Dropped dummy INTF_0 on MSM8953 - Corrected INTFs related to DP-MST - DP: - Removed debug prints looking into PHY internals - DSI: - Fixes for DSC panels - RGB101010 support - Support for SC8280XP - Moved PHY bindings from display/ to phy/ - GPU: - Preemption support for x2-85 and a840 - IFPC support for a840 - SKU detection support for x2-85 and a840 - Expose AQE support (VK ray-pipeline) - Avoid locking in VM_BIND fence signaling path - Fix to avoid reclaim in GPU snapshot path - Disallow foreign mapping of _NO_SHARE BOs - HDMI: - Fixed infoframes programming - MDP5: - Dropped support for MSM8974v1 - Dropped now unused code for MSM8974 v1 and SDM660 / MSM8998 panthor: - add tracepoints for power and IRQs - fix fence handling - extend timestamp query with flags - support various sources for timestamp queries tyr: - fix names and model/versions rockchip: - vop2: use drm logging function - rk3576 displayport support - support CRTC background color atmel-hlcdc: - support sana5d65 LCD controller tilcdc: - use DT bindings schema - use managed DRM interfaces - support DRM_BRIDGE_ATTACH_NO_CONNECTOR verisilicon: - support DC8200 + DT bindings virtgpu: - support PRIME import with 3D enabled komeda: - fix integer overflow in AFBC checks mcde: - improve bridge handling gma500: - use drm client buffer for fbdev framebuffer amdxdna: - add sensors ioctls - provide NPU power estimate - support column utilization sensor - allow forcing DMA through IOMMU IOVA - support per-BO mem usage queries - refactor GEM implementation ivpu: - update boot API to v3.29.4 - limit per-user number of doorbells/contexts - perform engine reset on TDR error loongson: - replace custom code with drm_gem_ttm_dumb_map_offset() imx: - support planes behind the primary plane - fix bus-format selection vkms: - support CRTC background color v3d: - improve handling of struct v3d_stats komeda: - support Arm China Linlon D6 plus DT bindings imagination: - improve power-off sequence - support context-reset notification from firmware mediatek: - mtk_dsi: enable hs clock during pre-enable - Remove all conflicting aperture devices during probe - Add support for mt8167 display blocks" * tag 'drm-next-2026-04-15' of https://gitlab.freedesktop.org/drm/kernel: (1735 commits) drm/ttm/tests: Remove checks from ttm_pool_free_no_dma_alloc drm/ttm/tests: fix lru_count ASSERT drm/vram: remove DRM_VRAM_MM_FILE_OPERATIONS from docs drm/fb-helper: Fix a locking bug in an error path dma-fence: correct kernel-doc function parameter @flags ttm/pool: track allocated_pages per numa node. ttm/pool: make pool shrinker NUMA aware (v2) ttm/pool: drop numa specific pools ttm/pool: port to list_lru. (v2) drm/ttm: use gpu mm stats to track gpu memory allocations. (v4) mm: add gpu active/reclaim per-node stat counters (v2) gpu: nova-core: fix missing colon in SEC2 boot debug message gpu: nova-core: vbios: use from_le_bytes() for PCI ROM header parsing gpu: nova-core: bitfield: fix broken Default implementation gpu: nova-core: falcon: pad firmware DMA object size to required block alignment gpu: nova-core: gsp: fix undefined behavior in command queue code drm/shmem_helper: Make sure PMD entries get the writeable upgrade accel/ivpu: Trigger recovery on TDR with OS scheduling drm/msm: Use of_get_available_child_by_name() dt-bindings: display/msm: move DSI PHY bindings to phy/ subdir ...

dma-buf: fix UAF in dma_buf_put() tracepoint

2026-04-13T13:59:22+00:00

dma_buf_put() may drop the final file reference via fput(), which can free the dma-buf. The new tracepoint invocation was added after fput(), and DMA_BUF_TRACE() dereferences dmabuf and takes dmabuf->name_lock. This leads to a use-after-free on the final put, visible for example as a spinlock bad magic fault on a poisoned 0x6b6b6b... lock. Move the dma_buf_put tracepoint before fput(). Reported-by: Janusz Krzysztofik Fixes: 281a22631423 ("dma-buf: add some tracepoints to debug.") Signed-off-by: Andi Shyti Reviewed-by: Christian König Signed-off-by: Christian König Link: https://lore.kernel.org/r/20260408123916.2604101-1-andi.shyti@kernel.org

dma-buf: fix htmldocs error for dma_buf_attach_revocable

2026-04-10T13:52:02+00:00

linux-next testing showed this htmldoc error due to a missing extra line in the comments; add it. Fixes: be6d4c9e9d714 ("dma-buf: Add dma_buf_attach_revocable()") Reported-by: Mark Brown Closes: https://lore.kernel.org/lkml/adaNJaF58PZlvs6K@sirena.org.uk/ Signed-off-by: Sumit Semwal Reviewed-by: Christian König Link: https://patch.msgid.link/20260410123703.937822-1-sumit.semwal@linaro.org

treewide: change inode->i_ino from unsigned long to u64

2026-03-06T13:31:28+00:00

On 32-bit architectures, unsigned long is only 32 bits wide, which causes 64-bit inode numbers to be silently truncated. Several filesystems (NFS, XFS, BTRFS, etc.) can generate inode numbers that exceed 32 bits, and this truncation can lead to inode number collisions and other subtle bugs on 32-bit systems. Change the type of inode->i_ino from unsigned long to u64 to ensure that inode numbers are always represented as 64-bit values regardless of architecture. Update all format specifiers treewide from %lu/%lx to %llu/%llx to match the new type, along with corresponding local variable types. This is the bulk treewide conversion. Earlier patches in this series handled trace events separately to allow trace field reordering for better struct packing on 32-bit. Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20260304-iino-u64-v3-12-2257ad83d372@kernel.org Acked-by: Damien Le Moal Reviewed-by: Christoph Hellwig Reviewed-by: Jan Kara Reviewed-by: Chuck Lever Signed-off-by: Christian Brauner

dma-buf: Add dma_buf_attach_revocable()

2026-02-23T18:51:40+00:00

Some exporters need a flow to synchronously revoke access to the DMA-buf by importers. Once revoke is completed the importer is not permitted to touch the memory otherwise they may get IOMMU faults, AERs, or worse. DMA-buf today defines a revoke flow, for both pinned and dynamic importers, which is broadly: dma_resv_lock(dmabuf->resv, NULL); // Prevent new mappings from being established priv->revoked = true; // Tell all importers to eventually unmap dma_buf_invalidate_mappings(dmabuf); // Wait for any inprogress fences on the old mapping dma_resv_wait_timeout(dmabuf->resv, DMA_RESV_USAGE_BOOKKEEP, false, MAX_SCHEDULE_TIMEOUT); dma_resv_unlock(dmabuf->resv, NULL); // Wait for all importers to complete unmap wait_for_completion(&priv->unmapped_comp); This works well, and an importer that continues to access the DMA-buf after unmapping it is very buggy. However, the final wait for unmap is effectively unbounded. Several importers do not support invalidate_mappings() at all and won't unmap until userspace triggers it. This unbounded wait is not suitable for exporters like VFIO and RDMA tha need to issue revoke as part of their normal operations. Add dma_buf_attach_revocable() to allow exporters to determine the difference between importers that can complete the above in bounded time, and those that can't. It can be called inside the exporter's attach op to reject incompatible importers. Document these details about how dma_buf_invalidate_mappings() works and what the required sequence is to achieve a full revocation. Signed-off-by: Leon Romanovsky Reviewed-by: Christian König Signed-off-by: Christian König Link: https://lore.kernel.org/r/20260131-dmabuf-revoke-v7-6-463d956bd527@nvidia.com

dma-buf: Make .invalidate_mapping() truly optional

2026-02-23T18:51:06+00:00

The .invalidate_mapping() callback is documented as optional, yet it effectively became mandatory whenever importer_ops were provided. This led to cases where RDMA non-ODP code had to supply an empty stub. Relax the checks in the dma-buf core so the callback can be omitted, allowing RDMA code to drop the unnecessary function. Removing the stub allows the next patch to tell that RDMA does not support .invalidate_mapping() by checking for a NULL op. Signed-off-by: Leon Romanovsky Reviewed-by: Christian König Signed-off-by: Christian König Link: https://lore.kernel.org/r/20260131-dmabuf-revoke-v7-5-463d956bd527@nvidia.com

Merge drm/drm-next into drm-misc-next

2026-02-23T10:48:20+00:00

Let's merge 7.0-rc1 to start the new drm-misc-next window Signed-off-by: Maxime Ripard