mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
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loongarch-next
113 Commits
Author | SHA1 | Message | Date | |
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2d8ae9a4f1 |
string: Group str_has_prefix() and strstarts()
The two str_has_prefix() and strstarts() are about the same with a slight difference on what they return. Group them in the header. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20250711085514.1294428-1-andriy.shevchenko@linux.intel.com Signed-off-by: Kees Cook <kees@kernel.org> |
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7bf819aa99 |
vsnprintf: Mark binary printing functions with __printf() attribute
Binary printf() functions are using printf() type of format, and compiler is not happy about them as is: lib/vsprintf.c:3130:47: error: function ‘vbin_printf’ might be a candidate for ‘gnu_printf’ format attribute [-Werror=suggest-attribute=format] lib/vsprintf.c:3298:33: error: function ‘bstr_printf’ might be a candidate for ‘gnu_printf’ format attribute [-Werror=suggest-attribute=format] Fix the compilation errors by adding __printf() attribute. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20250321144822.324050-5-andriy.shevchenko@linux.intel.com Signed-off-by: Petr Mladek <pmladek@suse.com> |
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1286f632a5 |
string.h: Validate memtostr*()/strtomem*() arguments more carefully
Since these functions handle moving between C strings and non-C strings, they should check for the appropriate presence/lack of the nonstring attribute on arguments. Signed-off-by: Kees Cook <kees@kernel.org> |
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9946eaf552 |
hardening fixes for v6.14-rc2
- Fix stackinit KUnit regression on m68k - Use ARRAY_SIZE() for memtostr*()/strtomem*() -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRSPkdeREjth1dHnSE2KwveOeQkuwUCZ6fBgQAKCRA2KwveOeQk u1HdAQCstqRZjXUqdG1jX56g1cW7RoLDtZC3Y9npyhVByUmFHgEAjsH1gmQcNswX 676kSkJaB3Iv4yQ17ozjlBWEd4xroAs= =YibW -----END PGP SIGNATURE----- Merge tag 'hardening-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening fixes from Kees Cook: "Address a KUnit stack initialization regression that got tickled on m68k, and solve a Clang(v14 and earlier) bug found by 0day: - Fix stackinit KUnit regression on m68k - Use ARRAY_SIZE() for memtostr*()/strtomem*()" * tag 'hardening-v6.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: string.h: Use ARRAY_SIZE() for memtostr*()/strtomem*() compiler.h: Introduce __must_be_byte_array() compiler.h: Move C string helpers into C-only kernel section stackinit: Fix comment for test_small_end stackinit: Keep selftest union size small on m68k |
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6270f4deba |
string.h: Use ARRAY_SIZE() for memtostr*()/strtomem*()
The destination argument of memtostr*() and strtomem*() must be a
fixed-size char array at compile time, so there is no need to use
__builtin_object_size() (which is useful for when an argument is
either a pointer or unknown). Instead use ARRAY_SIZE(), which has the
benefit of working around a bug in Clang (fixed[1] in 15+) that got
__builtin_object_size() wrong sometimes.
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202501310832.kiAeOt2z-lkp@intel.com/
Suggested-by: Kent Overstreet <kent.overstreet@linux.dev>
Link:
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9e49ca756d |
tracing/string: Create and use __free(argv_free) in trace_dynevent.c
The function dyn_event_release() uses argv_split() which must be freed via argv_free(). It contains several error paths that do a goto out to call argv_free() for cleanup. This makes the code complex and error prone. Create a new __free() directive __free(argv_free) that will call argv_free() for data allocated with argv_split(), and use it in the dyn_event_release() function. Cc: Kees Cook <kees@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Shevchenko <andy@kernel.org> Cc: linux-hardening@vger.kernel.org Link: https://lore.kernel.org/20241220103313.4a74ec8e@gandalf.local.home Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> |
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f69e63756f |
printf: Remove unused 'bprintf'
bprintf() is unused. Remove it. It was added in the commit
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de848da12f |
drm next for 6.12-rc1
string: - add mem_is_zero() core: - support more device numbers - use XArray for minor ids - add backlight constants - Split dma fence array creation into alloc and arm fbdev: - remove usage of old fbdev hooks kms: - Add might_fault() to drm_modeset_lock priming - Add dynamic per-crtc vblank configuration support dma-buf: - docs cleanup buddy: - Add start address support for trim function printk: - pass description to kmsg_dump scheduler; - Remove full_recover from drm_sched_start ttm: - Make LRU walk restartable after dropping locks - Allow direct reclaim to allocate local memory panic: - add display QR code (in rust) displayport: - mst: GUID improvements bridge: - Silence error message on -EPROBE_DEFER - analogix: Clean aup - bridge-connector: Fix double free - lt6505: Disable interrupt when powered off - tc358767: Make default DP port preemphasis configurable - lt9611uxc: require DRM_BRIDGE_ATTACH_NO_CONNECTOR - anx7625: simplify OF array handling - dw-hdmi: simplify clock handling - lontium-lt8912b: fix mode validation - nwl-dsi: fix mode vsync/hsync polarity xe: - Enable LunarLake and Battlemage support - Introducing Xe2 ccs modifiers for integrated and discrete graphics - rename xe perf to xe observation - use wb caching on DGFX for system memory - add fence timeouts - Lunar Lake graphics/media/display workarounds - Battlemage workarounds - Battlemage GSC support - GSC and HuC fw updates for LL/BM - use dma_fence_chain_free - refactor hw engine lookup and mmio access - enable priority mem read for Xe2 - Add first GuC BMG fw - fix dma-resv lock - Fix DGFX display suspend/resume - Use xe_managed for kernel BOs - Use reserved copy engine for user binds on faulting devices - Allow mixing dma-fence jobs and long-running faulting jobs - fix media TLB invalidation - fix rpm in TTM swapout path - track resources and VF state by PF i915: - Type-C programming fix for MTL+ - FBC cleanup - Calc vblank delay more accurately - On DP MST, Enable LT fallback for UHBR<->non-UHBR rates - Fix DP LTTPR detection - limit relocations to INT_MAX - fix long hangs in buddy allocator on DG2/A380 amdgpu: - Per-queue reset support - SDMA devcoredump support - DCN 4.0.1 updates - GFX12/VCN4/JPEG4 updates - Convert vbios embedded EDID to drm_edid - GFX9.3/9.4 devcoredump support - process isolation framework for GFX 9.4.3/4 - take IOMMU mappings into account for P2P DMA amdkfd: - CRIU fixes - HMM fix - Enable process isolation support for GFX 9.4.3/4 - Allow users to target recommended SDMA engines - KFD support for targetting queues on recommended SDMA engines radeon: - remove .load and drm_dev_alloc - Fix vbios embedded EDID size handling - Convert vbios embedded EDID to drm_edid - Use GEM references instead of TTM - r100 cp init cleanup - Fix potential overflows in evergreen CS offset tracking msm: - DPU: - implement DP/PHY mapping on SC8180X - Enable writeback on SM8150, SC8180X, SM6125, SM6350 - DP: - Enable widebus on all relevant chipsets - MSM8998 HDMI support - GPU: - A642L speedbin support - A615/A306/A621 support - A7xx devcoredump support ast: - astdp: Support AST2600 with VGA - Clean up HPD - Fix timeout loop for DP link training - reorganize output code by type (VGA, DP, etc) - convert to struct drm_edid - fix BMC handling for all outputs exynos: - drop stale MAINTAINERS pattern - constify struct loongson: - use GEM refcount over TTM mgag200: - Improve BMC handling - Support VBLANK intterupts - transparently support BMC outputs nouveau: - Refactor and clean up internals - Use GEM refcount over TTM's gm12u320: - convert to struct drm_edid gma500: - update i2c terms lcdif: - pixel clock fix host1x: - fix syncpoint IRQ during resume - use iommu_paging_domain_alloc() imx: - ipuv3: convert to struct drm_edid omapdrm: - improve error handling - use common helper for_each_endpoint_of_node() panel: - add support for BOE TV101WUM-LL2 plus DT bindings - novatek-nt35950: improve error handling - nv3051d: improve error handling - panel-edp: add support for BOE NE140WUM-N6G; revert support for SDC ATNA45AF01 - visionox-vtdr6130: improve error handling; use devm_regulator_bulk_get_const() - boe-th101mb31ig002: Support for starry-er88577 MIPI-DSI panel plus DT; Fix porch parameter - edp: Support AOU B116XTN02.3, AUO B116XAN06.1, AOU B116XAT04.1, BOE NV140WUM-N41, BOE NV133WUM-N63, BOE NV116WHM-A4D, CMN N116BCA-EA2, CMN N116BCP-EA2, CSW MNB601LS1-4 - himax-hx8394: Support Microchip AC40T08A MIPI Display panel plus DT - ilitek-ili9806e: Support Densitron DMT028VGHMCMI-1D TFT plus DT - jd9365da: Support Melfas lmfbx101117480 MIPI-DSI panel plus DT; Refactor for code sharing - panel-edp: fix name for HKC MB116AN01 - jd9365da: fix "exit sleep" commands - jdi-fhd-r63452: simplify error handling with DSI multi-style helpers - mantix-mlaf057we51: simplify error handling with DSI multi-style helpers - simple: support Innolux G070ACE-LH3 plus DT bindings support On Tat Industrial Company KD50G21-40NT-A1 plus DT bindings - st7701: decouple DSI and DRM code add SPI support support Anbernic RG28XX plus DT bindings mediatek: - support alpha blending - remove cl in struct cmdq_pkt - ovl adaptor fix - add power domain binding for mediatek DPI controller renesas: - rz-du: add support for RZ/G2UL plus DT bindings rockchip: - Improve DP sink-capability reporting - dw_hdmi: Support 4k@60Hz - vop: Support RGB display on Rockchip RK3066; Support 4096px width sti: - convert to struct drm_edid stm: - Avoid UAF wih managed plane and CRTC helpers - Fix module owner - Fix error handling in probe - Depend on COMMON_CLK - ltdc: Fix transparency after disabling plane; Remove unused interrupt tegra: - gr3d: improve PM domain handling - convert to struct drm_edid - Call drm_atomic_helper_shutdown() vc4: - fix PM during detect - replace DRM_ERROR() with drm_error() - v3d: simplify clock retrieval v3d: - Clean up perfmon virtio: - add DRM capset -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEEKbZHaGwW9KfbeusDHTzWXnEhr4FAmbq43gACgkQDHTzWXnE hr4+lg/+O/r41E7ioitcM0DWeWem0dTlvQr41pJ8jujHvw+bXNdg0BMGWtsTyTLA eOft2AwofsFjg+O7l8IFXOT37mQLdIdfjb3+w5brI198InL3OWC3QV8ZSwY9VGET n8crO9jFoxNmHZnFniBZbtI6egTyl6H+2ey3E0MTnKiPUKZQvsK/4+x532yVLPob UUOze5wcjyGZc7LJEIZPohPVneCb9ki7sabDQqh4cxIQ0Eg+nqPpWjYM4XVd+lTS 8QmssbR49LrJ7z9m90qVE+8TjYUCn+ChDPMs61KZAAnc8k++nK41btjGZ23mDKPb YEguahCYthWJ4U8K18iXBPnLPxZv5+harQ8OIWAUYqdIOWSXHozvuJ2Z84eHV13a 9mQ5vIymXang8G1nEXwX/vml9uhVhBCeWu3qfdse2jfaTWYUb1YzhqUoFvqI0R0K 8wT03MyNdx965CSqAhpH5Jd559ueZmpd+jsHOfhAS+1gxfD6NgoPXv7lpnMUmGWX SnaeC9RLD4cgy7j2Swo7TEqQHrvK5XhZSwX94kU6RPmFE5RRKqWgFVQmwuikDMId UpNqDnPT5NL2UX4TNG4V4coyTXvKgVcSB9TA7j8NSLfwdGHhiz73pkYosaZXKyxe u6qKMwMONfZiT20nhD7RhH0AFnnKosAcO14dhn0TKFZPY6Ce9O8= =7jR+ -----END PGP SIGNATURE----- Merge tag 'drm-next-2024-09-19' of https://gitlab.freedesktop.org/drm/kernel Pull drm updates from Dave Airlie: "This adds a couple of patches outside the drm core, all should be acked appropriately, the string and pstore ones are the main ones that come to mind. Otherwise it's the usual drivers, xe is getting enabled by default on some new hardware, we've changed the device number handling to allow more devices, and we added some optional rust code to create QR codes in the panic handler, an idea first suggested I think 10 years ago :-) string: - add mem_is_zero() core: - support more device numbers - use XArray for minor ids - add backlight constants - Split dma fence array creation into alloc and arm fbdev: - remove usage of old fbdev hooks kms: - Add might_fault() to drm_modeset_lock priming - Add dynamic per-crtc vblank configuration support dma-buf: - docs cleanup buddy: - Add start address support for trim function printk: - pass description to kmsg_dump scheduler: - Remove full_recover from drm_sched_start ttm: - Make LRU walk restartable after dropping locks - Allow direct reclaim to allocate local memory panic: - add display QR code (in rust) displayport: - mst: GUID improvements bridge: - Silence error message on -EPROBE_DEFER - analogix: Clean aup - bridge-connector: Fix double free - lt6505: Disable interrupt when powered off - tc358767: Make default DP port preemphasis configurable - lt9611uxc: require DRM_BRIDGE_ATTACH_NO_CONNECTOR - anx7625: simplify OF array handling - dw-hdmi: simplify clock handling - lontium-lt8912b: fix mode validation - nwl-dsi: fix mode vsync/hsync polarity xe: - Enable LunarLake and Battlemage support - Introducing Xe2 ccs modifiers for integrated and discrete graphics - rename xe perf to xe observation - use wb caching on DGFX for system memory - add fence timeouts - Lunar Lake graphics/media/display workarounds - Battlemage workarounds - Battlemage GSC support - GSC and HuC fw updates for LL/BM - use dma_fence_chain_free - refactor hw engine lookup and mmio access - enable priority mem read for Xe2 - Add first GuC BMG fw - fix dma-resv lock - Fix DGFX display suspend/resume - Use xe_managed for kernel BOs - Use reserved copy engine for user binds on faulting devices - Allow mixing dma-fence jobs and long-running faulting jobs - fix media TLB invalidation - fix rpm in TTM swapout path - track resources and VF state by PF i915: - Type-C programming fix for MTL+ - FBC cleanup - Calc vblank delay more accurately - On DP MST, Enable LT fallback for UHBR<->non-UHBR rates - Fix DP LTTPR detection - limit relocations to INT_MAX - fix long hangs in buddy allocator on DG2/A380 amdgpu: - Per-queue reset support - SDMA devcoredump support - DCN 4.0.1 updates - GFX12/VCN4/JPEG4 updates - Convert vbios embedded EDID to drm_edid - GFX9.3/9.4 devcoredump support - process isolation framework for GFX 9.4.3/4 - take IOMMU mappings into account for P2P DMA amdkfd: - CRIU fixes - HMM fix - Enable process isolation support for GFX 9.4.3/4 - Allow users to target recommended SDMA engines - KFD support for targetting queues on recommended SDMA engines radeon: - remove .load and drm_dev_alloc - Fix vbios embedded EDID size handling - Convert vbios embedded EDID to drm_edid - Use GEM references instead of TTM - r100 cp init cleanup - Fix potential overflows in evergreen CS offset tracking msm: - DPU: - implement DP/PHY mapping on SC8180X - Enable writeback on SM8150, SC8180X, SM6125, SM6350 - DP: - Enable widebus on all relevant chipsets - MSM8998 HDMI support - GPU: - A642L speedbin support - A615/A306/A621 support - A7xx devcoredump support ast: - astdp: Support AST2600 with VGA - Clean up HPD - Fix timeout loop for DP link training - reorganize output code by type (VGA, DP, etc) - convert to struct drm_edid - fix BMC handling for all outputs exynos: - drop stale MAINTAINERS pattern - constify struct loongson: - use GEM refcount over TTM mgag200: - Improve BMC handling - Support VBLANK intterupts - transparently support BMC outputs nouveau: - Refactor and clean up internals - Use GEM refcount over TTM's gm12u320: - convert to struct drm_edid gma500: - update i2c terms lcdif: - pixel clock fix host1x: - fix syncpoint IRQ during resume - use iommu_paging_domain_alloc() imx: - ipuv3: convert to struct drm_edid omapdrm: - improve error handling - use common helper for_each_endpoint_of_node() panel: - add support for BOE TV101WUM-LL2 plus DT bindings - novatek-nt35950: improve error handling - nv3051d: improve error handling - panel-edp: - add support for BOE NE140WUM-N6G - revert support for SDC ATNA45AF01 - visionox-vtdr6130: - improve error handling - use devm_regulator_bulk_get_const() - boe-th101mb31ig002: - Support for starry-er88577 MIPI-DSI panel plus DT - Fix porch parameter - edp: Support AOU B116XTN02.3, AUO B116XAN06.1, AOU B116XAT04.1, BOE NV140WUM-N41, BOE NV133WUM-N63, BOE NV116WHM-A4D, CMN N116BCA-EA2, CMN N116BCP-EA2, CSW MNB601LS1-4 - himax-hx8394: Support Microchip AC40T08A MIPI Display panel plus DT - ilitek-ili9806e: Support Densitron DMT028VGHMCMI-1D TFT plus DT - jd9365da: - Support Melfas lmfbx101117480 MIPI-DSI panel plus DT - Refactor for code sharing - panel-edp: fix name for HKC MB116AN01 - jd9365da: fix "exit sleep" commands - jdi-fhd-r63452: simplify error handling with DSI multi-style helpers - mantix-mlaf057we51: simplify error handling with DSI multi-style helpers - simple: - support Innolux G070ACE-LH3 plus DT bindings - support On Tat Industrial Company KD50G21-40NT-A1 plus DT bindings - st7701: - decouple DSI and DRM code - add SPI support - support Anbernic RG28XX plus DT bindings mediatek: - support alpha blending - remove cl in struct cmdq_pkt - ovl adaptor fix - add power domain binding for mediatek DPI controller renesas: - rz-du: add support for RZ/G2UL plus DT bindings rockchip: - Improve DP sink-capability reporting - dw_hdmi: Support 4k@60Hz - vop: - Support RGB display on Rockchip RK3066 - Support 4096px width sti: - convert to struct drm_edid stm: - Avoid UAF wih managed plane and CRTC helpers - Fix module owner - Fix error handling in probe - Depend on COMMON_CLK - ltdc: - Fix transparency after disabling plane - Remove unused interrupt tegra: - gr3d: improve PM domain handling - convert to struct drm_edid - Call drm_atomic_helper_shutdown() vc4: - fix PM during detect - replace DRM_ERROR() with drm_error() - v3d: simplify clock retrieval v3d: - Clean up perfmon virtio: - add DRM capset" * tag 'drm-next-2024-09-19' of https://gitlab.freedesktop.org/drm/kernel: (1326 commits) drm/xe: Fix missing conversion to xe_display_pm_runtime_resume drm/xe/xe2hpg: Add Wa_15016589081 drm/xe: Don't keep stale pointer to bo->ggtt_node drm/xe: fix missing 'xe_vm_put' drm/xe: fix build warning with CONFIG_PM=n drm/xe: Suppress missing outer rpm protection warning drm/xe: prevent potential UAF in pf_provision_vf_ggtt() drm/amd/display: Add all planes on CRTC to state for overlay cursor drm/i915/bios: fix printk format width drm/i915/display: Fix BMG CCS modifiers drm/amdgpu: get rid of bogus includes of fdtable.h drm/amdkfd: CRIU fixes drm/amdgpu: fix a race in kfd_mem_export_dmabuf() drm: new helper: drm_gem_prime_handle_to_dmabuf() drm/amdgpu/atomfirmware: Silence UBSAN warning drm/amdgpu: Fix kdoc entry in 'amdgpu_vm_cpu_prepare' drm/amd/amdgpu: apply command submission parser for JPEG v1 drm/amd/amdgpu: apply command submission parser for JPEG v2+ drm/amd/pm: fix the pp_dpm_pcie issue on smu v14.0.2/3 drm/amd/pm: update the features set on smu v14.0.2/3 ... |
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559048d156 |
string: Check for "nonstring" attribute on strscpy() arguments
GCC already checks for arguments that are marked with the "nonstring"[1] attribute when used on standard C String API functions (e.g. strcpy). Gain this compile-time checking also for the kernel's primary string copying function, strscpy(). Note that Clang has neither "nonstring" nor __builtin_has_attribute(). Link: https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#index-nonstring-variable-attribute [1] Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Tested-by: Miguel Ojeda <ojeda@kernel.org> Link: https://lore.kernel.org/r/20240805214340.work.339-kees@kernel.org Signed-off-by: Kees Cook <kees@kernel.org> |
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3942bb4972 |
string: add mem_is_zero() helper to check if memory area is all zeros
Almost two thirds of the memchr_inv() usages check if the memory area is all zeros, with no interest in where in the buffer the first non-zero byte is located. Checking for !memchr_inv(s, 0, n) is also not very intuitive or discoverable. Add an explicit mem_is_zero() helper for this use case. Reviewed-by: Kees Cook <kees@kernel.org> Reviewed-by: Andy Shevchenko <andy@kernel.org> Link: https://patchwork.freedesktop.org/patch/msgid/20240814100035.3100852-1-jani.nikula@intel.com Signed-off-by: Jani Nikula <jani.nikula@intel.com> |
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0ee1472547 |
mm/util: Swap kmemdup_array() arguments
GCC 14.1 complains about the argument usage of kmemdup_array(): drivers/soc/tegra/fuse/fuse-tegra.c:130:65: error: 'kmemdup_array' sizes specified with 'sizeof' in the earlier argument and not in the later argument [-Werror=calloc-transposed-args] 130 | fuse->lookups = kmemdup_array(fuse->soc->lookups, sizeof(*fuse->lookups), | ^ drivers/soc/tegra/fuse/fuse-tegra.c:130:65: note: earlier argument should specify number of elements, later size of each element The annotation introduced by commit |
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61307b7be4 |
The usual shower of singleton fixes and minor series all over MM,
documented (hopefully adequately) in the respective changelogs. Notable series include: - Lucas Stach has provided some page-mapping cleanup/consolidation/maintainability work in the series "mm/treewide: Remove pXd_huge() API". - In the series "Allow migrate on protnone reference with MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's MPOL_PREFERRED_MANY mode, yielding almost doubled performance in one test. - In their series "Memory allocation profiling" Kent Overstreet and Suren Baghdasaryan have contributed a means of determining (via /proc/allocinfo) whereabouts in the kernel memory is being allocated: number of calls and amount of memory. - Matthew Wilcox has provided the series "Various significant MM patches" which does a number of rather unrelated things, but in largely similar code sites. - In his series "mm: page_alloc: freelist migratetype hygiene" Johannes Weiner has fixed the page allocator's handling of migratetype requests, with resulting improvements in compaction efficiency. - In the series "make the hugetlb migration strategy consistent" Baolin Wang has fixed a hugetlb migration issue, which should improve hugetlb allocation reliability. - Liu Shixin has hit an I/O meltdown caused by readahead in a memory-tight memcg. Addressed in the series "Fix I/O high when memory almost met memcg limit". - In the series "mm/filemap: optimize folio adding and splitting" Kairui Song has optimized pagecache insertion, yielding ~10% performance improvement in one test. - Baoquan He has cleaned up and consolidated the early zone initialization code in the series "mm/mm_init.c: refactor free_area_init_core()". - Baoquan has also redone some MM initializatio code in the series "mm/init: minor clean up and improvement". - MM helper cleanups from Christoph Hellwig in his series "remove follow_pfn". - More cleanups from Matthew Wilcox in the series "Various page->flags cleanups". - Vlastimil Babka has contributed maintainability improvements in the series "memcg_kmem hooks refactoring". - More folio conversions and cleanups in Matthew Wilcox's series "Convert huge_zero_page to huge_zero_folio" "khugepaged folio conversions" "Remove page_idle and page_young wrappers" "Use folio APIs in procfs" "Clean up __folio_put()" "Some cleanups for memory-failure" "Remove page_mapping()" "More folio compat code removal" - David Hildenbrand chipped in with "fs/proc/task_mmu: convert hugetlb functions to work on folis". - Code consolidation and cleanup work related to GUP's handling of hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2". - Rick Edgecombe has developed some fixes to stack guard gaps in the series "Cover a guard gap corner case". - Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the series "mm/ksm: fix ksm exec support for prctl". - Baolin Wang has implemented NUMA balancing for multi-size THPs. This is a simple first-cut implementation for now. The series is "support multi-size THP numa balancing". - Cleanups to vma handling helper functions from Matthew Wilcox in the series "Unify vma_address and vma_pgoff_address". - Some selftests maintenance work from Dev Jain in the series "selftests/mm: mremap_test: Optimizations and style fixes". - Improvements to the swapping of multi-size THPs from Ryan Roberts in the series "Swap-out mTHP without splitting". - Kefeng Wang has significantly optimized the handling of arm64's permission page faults in the series "arch/mm/fault: accelerate pagefault when badaccess" "mm: remove arch's private VM_FAULT_BADMAP/BADACCESS" - GUP cleanups from David Hildenbrand in "mm/gup: consistently call it GUP-fast". - hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault path to use struct vm_fault". - selftests build fixes from John Hubbard in the series "Fix selftests/mm build without requiring "make headers"". - Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the series "Improved Memory Tier Creation for CPUless NUMA Nodes". Fixes the initialization code so that migration between different memory types works as intended. - David Hildenbrand has improved follow_pte() and fixed an errant driver in the series "mm: follow_pte() improvements and acrn follow_pte() fixes". - David also did some cleanup work on large folio mapcounts in his series "mm: mapcount for large folios + page_mapcount() cleanups". - Folio conversions in KSM in Alex Shi's series "transfer page to folio in KSM". - Barry Song has added some sysfs stats for monitoring multi-size THP's in the series "mm: add per-order mTHP alloc and swpout counters". - Some zswap cleanups from Yosry Ahmed in the series "zswap same-filled and limit checking cleanups". - Matthew Wilcox has been looking at buffer_head code and found the documentation to be lacking. The series is "Improve buffer head documentation". - Multi-size THPs get more work, this time from Lance Yang. His series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free" optimizes the freeing of these things. - Kemeng Shi has added more userspace-visible writeback instrumentation in the series "Improve visibility of writeback". - Kemeng Shi then sent some maintenance work on top in the series "Fix and cleanups to page-writeback". - Matthew Wilcox reduces mmap_lock traffic in the anon vma code in the series "Improve anon_vma scalability for anon VMAs". Intel's test bot reported an improbable 3x improvement in one test. - SeongJae Park adds some DAMON feature work in the series "mm/damon: add a DAMOS filter type for page granularity access recheck" "selftests/damon: add DAMOS quota goal test" - Also some maintenance work in the series "mm/damon/paddr: simplify page level access re-check for pageout" "mm/damon: misc fixes and improvements" - David Hildenbrand has disabled some known-to-fail selftests ni the series "selftests: mm: cow: flag vmsplice() hugetlb tests as XFAIL". - memcg metadata storage optimizations from Shakeel Butt in "memcg: reduce memory consumption by memcg stats". - DAX fixes and maintenance work from Vishal Verma in the series "dax/bus.c: Fixups for dax-bus locking". -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZkgQYwAKCRDdBJ7gKXxA jrdKAP9WVJdpEcXxpoub/vVE0UWGtffr8foifi9bCwrQrGh5mgEAx7Yf0+d/oBZB nvA4E0DcPrUAFy144FNM0NTCb7u9vAw= =V3R/ -----END PGP SIGNATURE----- Merge tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull mm updates from Andrew Morton: "The usual shower of singleton fixes and minor series all over MM, documented (hopefully adequately) in the respective changelogs. Notable series include: - Lucas Stach has provided some page-mapping cleanup/consolidation/ maintainability work in the series "mm/treewide: Remove pXd_huge() API". - In the series "Allow migrate on protnone reference with MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's MPOL_PREFERRED_MANY mode, yielding almost doubled performance in one test. - In their series "Memory allocation profiling" Kent Overstreet and Suren Baghdasaryan have contributed a means of determining (via /proc/allocinfo) whereabouts in the kernel memory is being allocated: number of calls and amount of memory. - Matthew Wilcox has provided the series "Various significant MM patches" which does a number of rather unrelated things, but in largely similar code sites. - In his series "mm: page_alloc: freelist migratetype hygiene" Johannes Weiner has fixed the page allocator's handling of migratetype requests, with resulting improvements in compaction efficiency. - In the series "make the hugetlb migration strategy consistent" Baolin Wang has fixed a hugetlb migration issue, which should improve hugetlb allocation reliability. - Liu Shixin has hit an I/O meltdown caused by readahead in a memory-tight memcg. Addressed in the series "Fix I/O high when memory almost met memcg limit". - In the series "mm/filemap: optimize folio adding and splitting" Kairui Song has optimized pagecache insertion, yielding ~10% performance improvement in one test. - Baoquan He has cleaned up and consolidated the early zone initialization code in the series "mm/mm_init.c: refactor free_area_init_core()". - Baoquan has also redone some MM initializatio code in the series "mm/init: minor clean up and improvement". - MM helper cleanups from Christoph Hellwig in his series "remove follow_pfn". - More cleanups from Matthew Wilcox in the series "Various page->flags cleanups". - Vlastimil Babka has contributed maintainability improvements in the series "memcg_kmem hooks refactoring". - More folio conversions and cleanups in Matthew Wilcox's series: "Convert huge_zero_page to huge_zero_folio" "khugepaged folio conversions" "Remove page_idle and page_young wrappers" "Use folio APIs in procfs" "Clean up __folio_put()" "Some cleanups for memory-failure" "Remove page_mapping()" "More folio compat code removal" - David Hildenbrand chipped in with "fs/proc/task_mmu: convert hugetlb functions to work on folis". - Code consolidation and cleanup work related to GUP's handling of hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2". - Rick Edgecombe has developed some fixes to stack guard gaps in the series "Cover a guard gap corner case". - Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the series "mm/ksm: fix ksm exec support for prctl". - Baolin Wang has implemented NUMA balancing for multi-size THPs. This is a simple first-cut implementation for now. The series is "support multi-size THP numa balancing". - Cleanups to vma handling helper functions from Matthew Wilcox in the series "Unify vma_address and vma_pgoff_address". - Some selftests maintenance work from Dev Jain in the series "selftests/mm: mremap_test: Optimizations and style fixes". - Improvements to the swapping of multi-size THPs from Ryan Roberts in the series "Swap-out mTHP without splitting". - Kefeng Wang has significantly optimized the handling of arm64's permission page faults in the series "arch/mm/fault: accelerate pagefault when badaccess" "mm: remove arch's private VM_FAULT_BADMAP/BADACCESS" - GUP cleanups from David Hildenbrand in "mm/gup: consistently call it GUP-fast". - hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault path to use struct vm_fault". - selftests build fixes from John Hubbard in the series "Fix selftests/mm build without requiring "make headers"". - Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the series "Improved Memory Tier Creation for CPUless NUMA Nodes". Fixes the initialization code so that migration between different memory types works as intended. - David Hildenbrand has improved follow_pte() and fixed an errant driver in the series "mm: follow_pte() improvements and acrn follow_pte() fixes". - David also did some cleanup work on large folio mapcounts in his series "mm: mapcount for large folios + page_mapcount() cleanups". - Folio conversions in KSM in Alex Shi's series "transfer page to folio in KSM". - Barry Song has added some sysfs stats for monitoring multi-size THP's in the series "mm: add per-order mTHP alloc and swpout counters". - Some zswap cleanups from Yosry Ahmed in the series "zswap same-filled and limit checking cleanups". - Matthew Wilcox has been looking at buffer_head code and found the documentation to be lacking. The series is "Improve buffer head documentation". - Multi-size THPs get more work, this time from Lance Yang. His series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free" optimizes the freeing of these things. - Kemeng Shi has added more userspace-visible writeback instrumentation in the series "Improve visibility of writeback". - Kemeng Shi then sent some maintenance work on top in the series "Fix and cleanups to page-writeback". - Matthew Wilcox reduces mmap_lock traffic in the anon vma code in the series "Improve anon_vma scalability for anon VMAs". Intel's test bot reported an improbable 3x improvement in one test. - SeongJae Park adds some DAMON feature work in the series "mm/damon: add a DAMOS filter type for page granularity access recheck" "selftests/damon: add DAMOS quota goal test" - Also some maintenance work in the series "mm/damon/paddr: simplify page level access re-check for pageout" "mm/damon: misc fixes and improvements" - David Hildenbrand has disabled some known-to-fail selftests ni the series "selftests: mm: cow: flag vmsplice() hugetlb tests as XFAIL". - memcg metadata storage optimizations from Shakeel Butt in "memcg: reduce memory consumption by memcg stats". - DAX fixes and maintenance work from Vishal Verma in the series "dax/bus.c: Fixups for dax-bus locking"" * tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (426 commits) memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order selftests/mm: hugetlb_madv_vs_map: avoid test skipping by querying hugepage size at runtime mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_wp mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_fault selftests: cgroup: add tests to verify the zswap writeback path mm: memcg: make alloc_mem_cgroup_per_node_info() return bool mm/damon/core: fix return value from damos_wmark_metric_value mm: do not update memcg stats for NR_{FILE/SHMEM}_PMDMAPPED selftests: cgroup: remove redundant enabling of memory controller Docs/mm/damon/maintainer-profile: allow posting patches based on damon/next tree Docs/mm/damon/maintainer-profile: change the maintainer's timezone from PST to PT Docs/mm/damon/design: use a list for supported filters Docs/admin-guide/mm/damon/usage: fix wrong schemes effective quota update command Docs/admin-guide/mm/damon/usage: fix wrong example of DAMOS filter matching sysfs file selftests/damon: classify tests for functionalities and regressions selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None' selftests/damon/_damon_sysfs: find sysfs mount point from /proc/mounts selftests/damon/_damon_sysfs: check errors from nr_schemes file reads mm/damon/core: initialize ->esz_bp from damos_quota_init_priv() selftests/damon: add a test for DAMOS quota goal ... |
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7d78a77733 |
string: Add additional __realloc_size() annotations for "dup" helpers
Several other "dup"-style interfaces could use the __realloc_size() attribute. (As a reminder to myself and others: "realloc" is used here instead of "alloc" because the "alloc_size" attribute implies that the memory contents are uninitialized. Since we're copying contents into the resulting allocation, it must use "realloc_size" to avoid confusing the compiler's optimization passes.) Add KUnit test coverage where possible. (KUnit still does not have the ability to manipulate userspace memory.) Reviewed-by: Andy Shevchenko <andy@kernel.org> Link: https://lore.kernel.org/r/20240502145218.it.729-kees@kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> |
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7bd230a266 |
mm/slab: enable slab allocation tagging for kmalloc and friends
Redefine kmalloc, krealloc, kzalloc, kcalloc, etc. to record allocations and deallocations done by these functions. [surenb@google.com: undo _noprof additions in the documentation] Link: https://lkml.kernel.org/r/20240326231453.1206227-7-surenb@google.com [rdunlap@infradead.org: fix kcalloc() kernel-doc warnings] Link: https://lkml.kernel.org/r/20240327044649.9199-1-rdunlap@infradead.org Link: https://lkml.kernel.org/r/20240321163705.3067592-26-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Co-developed-by: Kent Overstreet <kent.overstreet@linux.dev> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Kees Cook <keescook@chromium.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alex Gaynor <alex.gaynor@gmail.com> Cc: Alice Ryhl <aliceryhl@google.com> Cc: Andreas Hindborg <a.hindborg@samsung.com> Cc: Benno Lossin <benno.lossin@proton.me> Cc: "Björn Roy Baron" <bjorn3_gh@protonmail.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Christoph Lameter <cl@linux.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Gary Guo <gary@garyguo.net> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wedson Almeida Filho <wedsonaf@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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0efc5990bc |
string.h: Introduce memtostr() and memtostr_pad()
Another ambiguous use of strncpy() is to copy from strings that may not be NUL-terminated. These cases depend on having the destination buffer be explicitly larger than the source buffer's maximum size, having the size of the copy exactly match the source buffer's maximum size, and for the destination buffer to get explicitly NUL terminated. This usually happens when parsing protocols or hardware character arrays that are not guaranteed to be NUL-terminated. The code pattern is effectively this: char dest[sizeof(src) + 1]; strncpy(dest, src, sizeof(src)); dest[sizeof(dest) - 1] = '\0'; In practice it usually looks like: struct from_hardware { ... char name[HW_NAME_SIZE] __nonstring; ... }; struct from_hardware *p = ...; char name[HW_NAME_SIZE + 1]; strncpy(name, p->name, HW_NAME_SIZE); name[NW_NAME_SIZE] = '\0'; This cannot be replaced with: strscpy(name, p->name, sizeof(name)); because p->name is smaller and not NUL-terminated, so FORTIFY will trigger when strnlen(p->name, sizeof(name)) is used. And it cannot be replaced with: strscpy(name, p->name, sizeof(p->name)); because then "name" may contain a 1 character early truncation of p->name. Provide an unambiguous interface for converting a maybe not-NUL-terminated string to a NUL-terminated string, with compile-time buffer size checking so that it can never fail at runtime: memtostr() and memtostr_pad(). Also add KUnit tests for both. Link: https://lore.kernel.org/r/20240410023155.2100422-1-keescook@chromium.org Signed-off-by: Kees Cook <keescook@chromium.org> |
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216532e147 |
hardening updates for v6.9-rc1
- string.h and related header cleanups (Tanzir Hasan, Andy Shevchenko) - VMCI memcpy() usage and struct_size() cleanups (Vasiliy Kovalev, Harshit Mogalapalli) - selftests/powerpc: Fix load_unaligned_zeropad build failure (Michael Ellerman) - hardened Kconfig fragment updates (Marco Elver, Lukas Bulwahn) - Handle tail call optimization better in LKDTM (Douglas Anderson) - Use long form types in overflow.h (Andy Shevchenko) - Add flags param to string_get_size() (Andy Shevchenko) - Add Coccinelle script for potential struct_size() use (Jacob Keller) - Fix objtool corner case under KCFI (Josh Poimboeuf) - Drop 13 year old backward compat CAP_SYS_ADMIN check (Jingzi Meng) - Add str_plural() helper (Michal Wajdeczko, Kees Cook) - Ignore relocations in .notes section - Add comments to explain how __is_constexpr() works - Fix m68k stack alignment expectations in stackinit Kunit test - Convert string selftests to KUnit - Add KUnit tests for fortified string functions - Improve reporting during fortified string warnings - Allow non-type arg to type_max() and type_min() - Allow strscpy() to be called with only 2 arguments - Add binary mode to leaking_addresses scanner - Various small cleanups to leaking_addresses scanner - Adding wrapping_*() arithmetic helper - Annotate initial signed integer wrap-around in refcount_t - Add explicit UBSAN section to MAINTAINERS - Fix UBSAN self-test warnings - Simplify UBSAN build via removal of CONFIG_UBSAN_SANITIZE_ALL - Reintroduce UBSAN's signed overflow sanitizer -----BEGIN PGP SIGNATURE----- iQJKBAABCgA0FiEEpcP2jyKd1g9yPm4TiXL039xtwCYFAmXvm5kWHGtlZXNjb29r QGNocm9taXVtLm9yZwAKCRCJcvTf3G3AJiQqD/4mM6SWZpYHKlR1nEiqIyz7Hqr9 g4oguuw6HIVNJXLyeBI5Hd43CTeHPA0e++EETqhUAt7HhErxfYJY+JB221nRYmu+ zhhQ7N/xbTMV/Je7AR03kQjhiMm8LyEcM2X4BNrsAcoCieQzmO3g0zSp8ISzLUE0 PEEmf1lOzMe3gK2KOFCPt5Hiz9sGWyN6at+BQubY18tQGtjEXYAQNXkpD5qhGn4a EF693r/17wmc8hvSsjf4AGaWy1k8crG0WfpMCZsaqftjj0BbvOC60IDyx4eFjpcy tGyAJKETq161AkCdNweIh2Q107fG3tm0fcvw2dv8Wt1eQCko6M8dUGCBinQs/thh TexjJFS/XbSz+IvxLqgU+C5qkOP23E0M9m1dbIbOFxJAya/5n16WOBlGr3ae2Wdq /+t8wVSJw3vZiku5emWdFYP1VsdIHUjVa5QizFaaRhzLGRwhxVV49SP4IQC/5oM5 3MAgNOFTP6yRQn9Y9wP+SZs+SsfaIE7yfKa9zOi4S+Ve+LI2v4YFhh8NCRiLkeWZ R1dhp8Pgtuq76f/v0qUaWcuuVeGfJ37M31KOGIhi1sI/3sr7UMrngL8D1+F8UZMi zcLu+x4GtfUZCHl6znx1rNUBqE5S/5ndVhLpOqfCXKaQ+RAm7lkOJ3jXE2VhNkhp yVEmeSOLnlCaQjZvXQ== =OP+o -----END PGP SIGNATURE----- Merge tag 'hardening-v6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: "As is pretty normal for this tree, there are changes all over the place, especially for small fixes, selftest improvements, and improved macro usability. Some header changes ended up landing via this tree as they depended on the string header cleanups. Also, a notable set of changes is the work for the reintroduction of the UBSAN signed integer overflow sanitizer so that we can continue to make improvements on the compiler side to make this sanitizer a more viable future security hardening option. Summary: - string.h and related header cleanups (Tanzir Hasan, Andy Shevchenko) - VMCI memcpy() usage and struct_size() cleanups (Vasiliy Kovalev, Harshit Mogalapalli) - selftests/powerpc: Fix load_unaligned_zeropad build failure (Michael Ellerman) - hardened Kconfig fragment updates (Marco Elver, Lukas Bulwahn) - Handle tail call optimization better in LKDTM (Douglas Anderson) - Use long form types in overflow.h (Andy Shevchenko) - Add flags param to string_get_size() (Andy Shevchenko) - Add Coccinelle script for potential struct_size() use (Jacob Keller) - Fix objtool corner case under KCFI (Josh Poimboeuf) - Drop 13 year old backward compat CAP_SYS_ADMIN check (Jingzi Meng) - Add str_plural() helper (Michal Wajdeczko, Kees Cook) - Ignore relocations in .notes section - Add comments to explain how __is_constexpr() works - Fix m68k stack alignment expectations in stackinit Kunit test - Convert string selftests to KUnit - Add KUnit tests for fortified string functions - Improve reporting during fortified string warnings - Allow non-type arg to type_max() and type_min() - Allow strscpy() to be called with only 2 arguments - Add binary mode to leaking_addresses scanner - Various small cleanups to leaking_addresses scanner - Adding wrapping_*() arithmetic helper - Annotate initial signed integer wrap-around in refcount_t - Add explicit UBSAN section to MAINTAINERS - Fix UBSAN self-test warnings - Simplify UBSAN build via removal of CONFIG_UBSAN_SANITIZE_ALL - Reintroduce UBSAN's signed overflow sanitizer" * tag 'hardening-v6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (51 commits) selftests/powerpc: Fix load_unaligned_zeropad build failure string: Convert helpers selftest to KUnit string: Convert selftest to KUnit sh: Fix build with CONFIG_UBSAN=y compiler.h: Explain how __is_constexpr() works overflow: Allow non-type arg to type_max() and type_min() VMCI: Fix possible memcpy() run-time warning in vmci_datagram_invoke_guest_handler() lib/string_helpers: Add flags param to string_get_size() x86, relocs: Ignore relocations in .notes section objtool: Fix UNWIND_HINT_{SAVE,RESTORE} across basic blocks overflow: Use POD in check_shl_overflow() lib: stackinit: Adjust target string to 8 bytes for m68k sparc: vdso: Disable UBSAN instrumentation kernel.h: Move lib/cmdline.c prototypes to string.h leaking_addresses: Provide mechanism to scan binary files leaking_addresses: Ignore input device status lines leaking_addresses: Use File::Temp for /tmp files MAINTAINERS: Update LEAKING_ADDRESSES details fortify: Improve buffer overflow reporting fortify: Add KUnit tests for runtime overflows ... |
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57914905f3 |
kernel.h: Move lib/cmdline.c prototypes to string.h
The lib/cmdline.c is basically a set of some small string parsers which are wide used in the kernel. Their prototypes belong to the string.h rather then kernel.h. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://lore.kernel.org/r/20231003130142.2936503-1-andriy.shevchenko@linux.intel.com Signed-off-by: Kees Cook <keescook@chromium.org> |
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8366d124ec |
string: Allow 2-argument strscpy_pad()
Similar to strscpy(), update strscpy_pad()'s 3rd argument to be optional when the destination is a compile-time known size array. Cc: Andy Shevchenko <andy@kernel.org> Cc: <linux-hardening@vger.kernel.org> Reviewed-by: Justin Stitt <justinstitt@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> |
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e6584c3964 |
string: Allow 2-argument strscpy()
Using sizeof(dst) for the "size" argument in strscpy() is the overwhelmingly common case. Instead of requiring this everywhere, allow a 2-argument version to be used that will use the sizeof() internally. There are other functions in the kernel with optional arguments[1], so this isn't unprecedented, and improves readability. Update and relocate the kern-doc for strscpy() too, and drop __HAVE_ARCH_STRSCPY as it is unused. Adjust ARCH=um build to notice the changed export name, as it doesn't do full header includes for the string helpers. This could additionally let us save a few hundred lines of code: 1177 files changed, 2455 insertions(+), 3026 deletions(-) with a treewide cleanup using Coccinelle: @needless_arg@ expression DST, SRC; @@ strscpy(DST, SRC -, sizeof(DST) ) Link: https://elixir.bootlin.com/linux/v6.7/source/include/linux/pci.h#L1517 [1] Reviewed-by: Justin Stitt <justinstitt@google.com> Cc: Andy Shevchenko <andy@kernel.org> Cc: linux-hardening@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> |
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f478898e0a |
string: Redefine strscpy_pad() as a macro
In preparation for making strscpy_pad()'s 3rd argument optional, redefine it as a macro. This also has the benefit of allowing greater FORITFY introspection, as it couldn't see into the strscpy() nor the memset() within strscpy_pad(). Cc: Andy Shevchenko <andy@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: <linux-hardening@vger.kernel.org> Reviewed-by: Justin Stitt <justinstitt@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> |
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7092e9b3be |
mm/util: Introduce kmemdup_array()
Introduce kmemdup_array() API to duplicate `n` number of elements from a given array. This internally uses kmemdup to allocate and duplicate the `src` array. Signed-off-by: Kartik <kkartik@nvidia.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Thierry Reding <treding@nvidia.com> |
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d26270061a |
string: Remove strlcpy()
With all the users of strlcpy() removed[1] from the kernel, remove the API, self-tests, and other references. Leave mentions in Documentation (about its deprecation), and in checkpatch.pl (to help migrate host-only tools/ usage). Long live strscpy(). Link: https://github.com/KSPP/linux/issues/89 [1] Cc: Azeem Shaikh <azeemshaikh38@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Whitcroft <apw@canonical.com> Cc: Joe Perches <joe@perches.com> Cc: Dwaipayan Ray <dwaipayanray1@gmail.com> Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com> Cc: linux-hardening@vger.kernel.org Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> |
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90b0c2b2ed |
Pin control changes for the v6.7 kernel cycle
New drivers: - Realtek RTD family pin control driver and RTD1619B, RTD1319D and RTD1315E subdrivers. - Nuvoton NPCM8xx combined pin control and GPIO driver. - Amlogic T7 pin control driver. - Renesas RZ/G3S pin control driver. Improvements: - A number of additional UART groups added to the Mediatek MT7981 driver. - MPM pin maps added for Qualcomm MSM8996, SM6115, SM6125 and SDM660. - Extra GPIO banks for the Sunxi H616. - MLSP I2C6 function support in Qualcomm MSM8226. - Some __counted_by() annotations for dynamic arrays. - Ongoing work to make remove() return void. - LSBC groups and functions in the Renesas R8A7778. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEElDRnuGcz/wPCXQWMQRCzN7AZXXMFAmVEp+oACgkQQRCzN7AZ XXPmqg/7BX2u2/1jpOpEjoqbUC7KEU3ptR2j1vAMCBibBq0IsnHVUH3DQ80leEpf gcf5vbY72PCTg5KGYZZ35XvrqzEP/z25qOnUZ+4Y7JljoXyNBb6eW1I3UstdPR1C E9hFVjMVFD7YePCGK/Ytwp/1dFLgLsADjk6Zc4gfHlPV/Op8NaxIIcM0FjFvu+X1 znf3lRkaxedhdM0TsL6efOoNXJNHGZNXI+dUzgbEr+fyYcjHJFjh8HejJvcZDyvc 581k6EVE0aGBz857OZz+ojADhtnE2+GYCB2kkdT5iHFeHtHGbRrwIc6Fh3gInMBI 6yj86AaZEFJwLec/ckMn+kWdKwF17Q2qUOryr7UHlU8YP5DBAjSAZaocFynNto+I ikQPde2s04tRpveMCJSYnvy2eQpJ2DEpWtkSAGMzg0Ly71zfSH1TMrhjR9AxDP0F nrIBB7hEzTosxvrFTXHcCh8LxSDlohUL/UveA2Tiz/m1gvR51OnIx61EzqizHF5x WkuLxgLlC4P1ZqFyV1guwcOqUD4rpwpqTyIgAIoVIQfnvZR5jgFXHBKDJPXyjJTD oDEX8fVWX0xzwAoqBXqVs/TJcD9q8qKuuPaK8266XP5D/zM/PP1jRKQnC8IFPSq2 Ory4TDLCrSmVw+c8q+jZHgKiEXuwGzPJ+ImypTMV+uZZzCdR4YE= =vonG -----END PGP SIGNATURE----- Merge tag 'pinctrl-v6.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl Pull pin control updates from Linus Walleij: "No pin control core changes this time. New drivers: - Realtek RTD family pin control driver and RTD1619B, RTD1319D and RTD1315E subdrivers - Nuvoton NPCM8xx combined pin control and GPIO driver - Amlogic T7 pin control driver - Renesas RZ/G3S pin control driver Improvements: - A number of additional UART groups added to the Mediatek MT7981 driver - MPM pin maps added for Qualcomm MSM8996, SM6115, SM6125 and SDM660 - Extra GPIO banks for the Sunxi H616 - MLSP I2C6 function support in Qualcomm MSM8226 - Some __counted_by() annotations for dynamic arrays - Ongoing work to make remove() return void - LSBC groups and functions in the Renesas R8A7778" * tag 'pinctrl-v6.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (110 commits) pinctrl: Use device_get_match_data() dt-bindings: pinctrl: qcom,sa8775p-tlmm: add missing wakeup-parent dt-bindings: pinctrl: nuvoton,npcm845: Add missing additionalProperties on gpio child nodes dt-bindings: pinctrl: brcm: Ensure all child node properties are documented pinctrl: renesas: rzn1: Convert to platform remove callback returning void pinctrl: renesas: rzg2l: Add RZ/G3S support dt-bindings: pinctrl: renesas: Document RZ/G3S SoC pinctrl: renesas: rzg2l: Add support for different DS values on different groups pinctrl: renesas: rzg2l: Move DS and OI to SoC-specific configuration pinctrl: renesas: rzg2l: Adapt function number for RZ/G3S pinctrl: renesas: rzg2l: Adapt for different SD/PWPR register offsets pinctrl: renesas: rzg2l: Index all registers based on port offset pinctrl: renesas: rzg2l: Add validation of GPIO pin in rzg2l_gpio_request() pinctrl: renesas: r8a7778: Add LBSC pins, groups, and functions pinctrl: intel: fetch community only when we need it pinctrl: cherryview: reduce scope of PIN_CONFIG_BIAS_HIGH_IMPEDANCE case pinctrl: cherryview: Convert to platform remove callback returning void pinctrl: sprd-sc9860: Convert to platform remove callback returning void pinctrl: qcom/msm: Convert to platform remove callback returning void pinctrl: qcom/lpi: Convert to platform remove callback returning void ... |
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7d461b291e |
drm for 6.7-rc1
kernel: - add initial vmemdup-user-array core: - fix platform remove() to return void - drm_file owner updated to reflect owner - move size calcs to drm buddy allocator - let GPUVM build as a module - allow variable number of run-queues in scheduler edid: - handle bad h/v sync_end in EDIDs panfrost: - add Boris as maintainer fbdev: - use fb_ops helpers more - only allow logo use from fbcon - rename fb_pgproto to pgprot_framebuffer - add HPD state to drm_connector_oob_hotplug_event - convert to fbdev i/o mem helpers i915: - Enable meteorlake by default - Early Xe2 LPD/Lunarlake display enablement - Rework subplatforms into IP version checks - GuC based TLB invalidation for Meteorlake - Display rework for future Xe driver integration - LNL FBC features - LNL display feature capability reads - update recommended fw versions for DG2+ - drop fastboot module parameter - added deviceid for Arrowlake-S - drop preproduction workarounds - don't disable preemption for resets - cleanup inlines in headers - PXP firmware loading fix - Fix sg list lengths - DSC PPS state readout/verification - Add more RPL P/U PCI IDs - Add new DG2-G12 stepping - DP enhanced framing support to state checker - Improve shared link bandwidth management - stop using GEM macros in display code - refactor related code into display code - locally enable W=1 warnings - remove PSR watchdog timers on LNL amdgpu: - RAS/FRU EEPROM updatse - IP discovery updatses - GC 11.5 support - DCN 3.5 support - VPE 6.1 support - NBIO 7.11 support - DML2 support - lots of IP updates - use flexible arrays for bo list handling - W=1 fixes - Enable seamless boot in more cases - Enable context type property for HDMI - Rework GPUVM TLB flushing - VCN IB start/size alignment fixes amdkfd: - GC 10/11 fixes - GC 11.5 support - use partial migration in GPU faults radeon: - W=1 Fixes - fix some possible buffer overflow/NULL derefs nouveau: - update uapi for NO_PREFETCH - scheduler/fence fixes - rework suspend/resume for GSP-RM - rework display in preparation for GSP-RM habanalabs: - uapi: expose tsc clock - uapi: block access to eventfd through control device - uapi: force dma-buf export to PAGE_SIZE alignments - complete move to accel subsystem - move firmware interface include files - perform hard reset on PCIe AXI drain event - optimise user interrupt handling msm: - DP: use existing helpers for DPCD - DPU: interrupts reworked - gpu: a7xx (a730/a740) support - decouple msm_drv from kms for headless devices mediatek: - MT8188 dsi/dp/edp support - DDP GAMMA - 12 bit LUT support - connector dynamic selection capability rockchip: - rv1126 mipi-dsi/vop support - add planar formats ast: - rename constants panels: - Mitsubishi AA084XE01 - JDI LPM102A188A - LTK050H3148W-CTA6 ivpu: - power management fixes qaic: - add detach slice bo api komeda: - add NV12 writeback tegra: - support NVSYNC/NHSYNC - host1x suspend fixes ili9882t: - separate into own driver -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEEKbZHaGwW9KfbeusDHTzWXnEhr4FAmVAgzYACgkQDHTzWXnE hr7ZEQ//UXne3tyGOsU3X8r+lstLFDMa90a3hvTg6hX+Q0MjHd/clwkKFkLpkipL n7gIZlaHl11dRs0FzrIZA5EVAAgjMLKmIl10NBDFec6ZFA3VERcggx8y61uifI15 VviMR1VbLHYZaCdyrQOK0A4wcktWnKXyoXp7cwy9crdc2GOBMUZkdIqtvD7jHxQx UMIFnzi1CyKUX/Fjt/JceYcNk9y2ZGkzakYO3sHcUdv4DPu9qX4kNzpjF691AZBP UeKWvCswTRVg2M0kuo/RYIBzqaTmOlk6dHLWBognIeZPyuyhCcaGC2d64c6tShwQ dtHdi+IgyQ8s2qb350ymKTQUP7xA/DfZBwH7LvrZALBxeQGYQN1CnsgDMOS2wcUc XrRFiS7PxEOtMMBctcPBnnoV5ttnsLLlPpzM9puh9sUFMn6CgLzcAMqXdqxzMajH +dz2aD1N0vMqq4varozOg9SC2QamgUiPN/TQfrulhCTCfQaXczy5x1OYiIz65+Sl mKoe2WASuP9Ve8do4N/wEwH5SZY2ItipBdUTRxttY9NTanmV0X5DjZBXH5b9XGci Zl5Ar613f9zwm5T5BVA5k6s3ZbGY6QcP5pDNTCPaSgitfFXIdReBZ2CaYzK3MPg/ Wit/TXrud9yT6VPpI1igboMyasf5QubV1MY1K83kOCWr9u8R2CM= =l79u -----END PGP SIGNATURE----- Merge tag 'drm-next-2023-10-31-1' of git://anongit.freedesktop.org/drm/drm Pull drm updates from Dave Airlie: "Highlights: - AMD adds some more upcoming HW platforms - Intel made Meteorlake stable and started adding Lunarlake - nouveau has a bunch of display rework in prepartion for the NVIDIA GSP firmware support - msm adds a7xx support - habanalabs has finished migration to accel subsystem Detail summary: kernel: - add initial vmemdup-user-array core: - fix platform remove() to return void - drm_file owner updated to reflect owner - move size calcs to drm buddy allocator - let GPUVM build as a module - allow variable number of run-queues in scheduler edid: - handle bad h/v sync_end in EDIDs panfrost: - add Boris as maintainer fbdev: - use fb_ops helpers more - only allow logo use from fbcon - rename fb_pgproto to pgprot_framebuffer - add HPD state to drm_connector_oob_hotplug_event - convert to fbdev i/o mem helpers i915: - Enable meteorlake by default - Early Xe2 LPD/Lunarlake display enablement - Rework subplatforms into IP version checks - GuC based TLB invalidation for Meteorlake - Display rework for future Xe driver integration - LNL FBC features - LNL display feature capability reads - update recommended fw versions for DG2+ - drop fastboot module parameter - added deviceid for Arrowlake-S - drop preproduction workarounds - don't disable preemption for resets - cleanup inlines in headers - PXP firmware loading fix - Fix sg list lengths - DSC PPS state readout/verification - Add more RPL P/U PCI IDs - Add new DG2-G12 stepping - DP enhanced framing support to state checker - Improve shared link bandwidth management - stop using GEM macros in display code - refactor related code into display code - locally enable W=1 warnings - remove PSR watchdog timers on LNL amdgpu: - RAS/FRU EEPROM updatse - IP discovery updatses - GC 11.5 support - DCN 3.5 support - VPE 6.1 support - NBIO 7.11 support - DML2 support - lots of IP updates - use flexible arrays for bo list handling - W=1 fixes - Enable seamless boot in more cases - Enable context type property for HDMI - Rework GPUVM TLB flushing - VCN IB start/size alignment fixes amdkfd: - GC 10/11 fixes - GC 11.5 support - use partial migration in GPU faults radeon: - W=1 Fixes - fix some possible buffer overflow/NULL derefs nouveau: - update uapi for NO_PREFETCH - scheduler/fence fixes - rework suspend/resume for GSP-RM - rework display in preparation for GSP-RM habanalabs: - uapi: expose tsc clock - uapi: block access to eventfd through control device - uapi: force dma-buf export to PAGE_SIZE alignments - complete move to accel subsystem - move firmware interface include files - perform hard reset on PCIe AXI drain event - optimise user interrupt handling msm: - DP: use existing helpers for DPCD - DPU: interrupts reworked - gpu: a7xx (a730/a740) support - decouple msm_drv from kms for headless devices mediatek: - MT8188 dsi/dp/edp support - DDP GAMMA - 12 bit LUT support - connector dynamic selection capability rockchip: - rv1126 mipi-dsi/vop support - add planar formats ast: - rename constants panels: - Mitsubishi AA084XE01 - JDI LPM102A188A - LTK050H3148W-CTA6 ivpu: - power management fixes qaic: - add detach slice bo api komeda: - add NV12 writeback tegra: - support NVSYNC/NHSYNC - host1x suspend fixes ili9882t: - separate into own driver" * tag 'drm-next-2023-10-31-1' of git://anongit.freedesktop.org/drm/drm: (1803 commits) drm/amdgpu: Remove unused variables from amdgpu_show_fdinfo drm/amdgpu: Remove duplicate fdinfo fields drm/amd/amdgpu: avoid to disable gfxhub interrupt when driver is unloaded drm/amdgpu: Add EXT_COHERENT support for APU and NUMA systems drm/amdgpu: Retrieve CE count from ce_count_lo_chip in EccInfo table drm/amdgpu: Identify data parity error corrected in replay mode drm/amdgpu: Fix typo in IP discovery parsing drm/amd/display: fix S/G display enablement drm/amdxcp: fix amdxcp unloads incompletely drm/amd/amdgpu: fix the GPU power print error in pm info drm/amdgpu: Use pcie domain of xcc acpi objects drm/amd: check num of link levels when update pcie param drm/amdgpu: Add a read to GFX v9.4.3 ring test drm/amd/pm: call smu_cmn_get_smc_version in is_mode1_reset_supported. drm/amdgpu: get RAS poison status from DF v4_6_2 drm/amdgpu: Use discovery table's subrevision drm/amd/display: 3.2.256 drm/amd/display: add interface to query SubVP status drm/amd/display: Read before writing Backlight Mode Set Register drm/amd/display: Disable SYMCLK32_SE RCO on DCN314 ... |
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0e108725f6 |
string: Adjust strtomem() logic to allow for smaller sources
Arnd noticed we have a case where a shorter source string is being copied
into a destination byte array, but this results in a strnlen() call that
exceeds the size of the source. This is seen with -Wstringop-overread:
In file included from ../include/linux/uuid.h:11,
from ../include/linux/mod_devicetable.h:14,
from ../include/linux/cpufeature.h:12,
from ../arch/x86/coco/tdx/tdx.c:7:
../arch/x86/coco/tdx/tdx.c: In function 'tdx_panic.constprop':
../include/linux/string.h:284:9: error: 'strnlen' specified bound 64 exceeds source size 60 [-Werror=stringop-overread]
284 | memcpy_and_pad(dest, _dest_len, src, strnlen(src, _dest_len), pad); \
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../arch/x86/coco/tdx/tdx.c:124:9: note: in expansion of macro 'strtomem_pad'
124 | strtomem_pad(message.str, msg, '\0');
| ^~~~~~~~~~~~
Use the smaller of the two buffer sizes when calling strnlen(). When
src length is unknown (SIZE_MAX), it is adjusted to use dest length,
which is what the original code did.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Fixes:
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313ebe47d7 |
string.h: add array-wrappers for (v)memdup_user()
Currently, user array duplications are sometimes done without an overflow check. Sometimes the checks are done manually; sometimes the array size is calculated with array_size() and sometimes by calculating n * size directly in code. Introduce wrappers for arrays for memdup_user() and vmemdup_user() to provide a standardized and safe way for duplicating user arrays. This is both for new code as well as replacing usage of (v)memdup_user() in existing code that uses, e.g., n * size to calculate array sizes. Suggested-by: David Airlie <airlied@redhat.com> Signed-off-by: Philipp Stanner <pstanner@redhat.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Zack Rusin <zackr@vmware.com> Signed-off-by: Dave Airlie <airlied@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20230920123612.16914-3-pstanner@redhat.com |
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3cd39bc3b1 |
kernel.h: Move ARRAY_SIZE() to a separate header
Touching files so used for the kernel, forces 'make' to recompile most of the kernel. Having those definitions in more granular files helps avoid recompiling so much of the kernel. Signed-off-by: Alejandro Colomar <alx@kernel.org> Reviewed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Link: https://lore.kernel.org/r/20230817143352.132583-2-lucas.segarra.fernandez@intel.com [andy: reduced to cover only string.h for now] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> |
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d01a77afd6 |
lib/string_helpers: Change returned value of the strreplace()
It's more useful to return the pointer to the string itself with strreplace(), so it may be used like attr->name = strreplace(name, '/', '_'); While at it, amend the kernel documentation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20230605170553.7835-3-andriy.shevchenko@linux.intel.com |
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0b7b8704dd |
mm: new primitive kvmemdup()
Similar to kmemdup(), but support large amount of bytes with kvmalloc() and does *not* guarantee that the result will be physically contiguous. Use only in cases where kvmalloc() is needed and free it with kvfree(). Also adapt policy_unpack.c in case someone bisect into this. Link: https://lkml.kernel.org/r/20221221144245.27164-1-sunhao.th@gmail.com Signed-off-by: Hao Sun <sunhao.th@gmail.com> Suggested-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Nick Terrell <terrelln@fb.com> Cc: John Johansen <john.johansen@canonical.com> Cc: Paul Moore <paul@paul-moore.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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9e4a617757 |
string: Add __realloc_size hint to kmemdup()
Add __realloc_size() hint to kmemdup() so the compiler can reason about the length of the returned buffer. (These must not use __alloc_size, since those include __malloc which says the contents aren't defined[1]). [1] https://lore.kernel.org/linux-hardening/d199c2af-06af-8a50-a6a1-00eefa0b67b4@prevas.dk/ Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Andy Shevchenko <andriy.shevchenko@intel.com> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Kees Cook <keescook@chromium.org> |
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dfbafa70bd |
string: Introduce strtomem() and strtomem_pad()
One of the "legitimate" uses of strncpy() is copying a NUL-terminated string into a fixed-size non-NUL-terminated character array. To avoid the weaknesses and ambiguity of intent when using strncpy(), provide replacement functions that explicitly distinguish between trailing padding and not, and require the destination buffer size be discoverable by the compiler. For example: struct obj { int foo; char small[4] __nonstring; char big[8] __nonstring; int bar; }; struct obj p; /* This will truncate to 4 chars with no trailing NUL */ strncpy(p.small, "hello", sizeof(p.small)); /* p.small contains 'h', 'e', 'l', 'l' */ /* This will NUL pad to 8 chars. */ strncpy(p.big, "hello", sizeof(p.big)); /* p.big contains 'h', 'e', 'l', 'l', 'o', '\0', '\0', '\0' */ When the "__nonstring" attributes are missing, the intent of the programmer becomes ambiguous for whether the lack of a trailing NUL in the p.small copy is a bug. Additionally, it's not clear whether the trailing padding in the p.big copy is _needed_. Both cases become unambiguous with: strtomem(p.small, "hello"); strtomem_pad(p.big, "hello", 0); See also https://github.com/KSPP/linux/issues/90 Expand the memcpy KUnit tests to include these functions. Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Kees Cook <keescook@chromium.org> |
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43213daed6 |
fortify: Provide a memcpy trap door for sharp corners
As we continue to narrow the scope of what the FORTIFY memcpy() will accept and build alternative APIs that give the compiler appropriate visibility into more complex memcpy scenarios, there is a need for "unfortified" memcpy use in rare cases where combinations of compiler behaviors, source code layout, etc, result in cases where the stricter memcpy checks need to be bypassed until appropriate solutions can be developed (i.e. fix compiler bugs, code refactoring, new API, etc). The intention is for this to be used only if there's no other reasonable solution, for its use to include a justification that can be used to assess future solutions, and for it to be temporary. Example usage included, based on analysis and discussion from: https://lore.kernel.org/netdev/CANn89iLS_2cshtuXPyNUGDPaic=sJiYfvTb_wNLgWrZRyBxZ_g@mail.gmail.com Cc: Jakub Kicinski <kuba@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Coco Li <lixiaoyan@google.com> Cc: Tariq Toukan <tariqt@nvidia.com> Cc: Saeed Mahameed <saeedm@nvidia.com> Cc: Leon Romanovsky <leon@kernel.org> Cc: netdev@vger.kernel.org Cc: linux-hardening@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220511025301.3636666-1-keescook@chromium.org Signed-off-by: Paolo Abeni <pabeni@redhat.com> |
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5c4e0a21fa |
string: uninline memcpy_and_pad
When building m68k:allmodconfig, recent versions of gcc generate the following error if the length of UTS_RELEASE is less than 8 bytes. In function 'memcpy_and_pad', inlined from 'nvmet_execute_disc_identify' at drivers/nvme/target/discovery.c:268:2: arch/m68k/include/asm/string.h:72:25: error: '__builtin_memcpy' reading 8 bytes from a region of size 7 Discussions around the problem suggest that this only happens if an architecture does not provide strlen(), if -ffreestanding is provided as compiler option, and if CONFIG_FORTIFY_SOURCE=n. All of this is the case for m68k. The exact reasons are unknown, but seem to be related to the ability of the compiler to evaluate the return value of strlen() and the resulting execution flow in memcpy_and_pad(). It would be possible to work around the problem by using sizeof(UTS_RELEASE) instead of strlen(UTS_RELEASE), but that would only postpone the problem until the function is called in a similar way. Uninline memcpy_and_pad() instead to solve the problem for good. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Andy Shevchenko <andriy.shevchenko@intel.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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6dbefad408 |
string.h: Introduce memset_startat() for wiping trailing members and padding
A common idiom in kernel code is to wipe the contents of a structure starting from a given member. These open-coded cases are usually difficult to read and very sensitive to struct layout changes. Like memset_after(), introduce a new helper, memset_startat() that takes the target struct instance, the byte to write, and the member name where zeroing should start. Note that this doesn't zero padding preceding the target member. For those cases, memset_after() should be used on the preceding member. Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Francis Laniel <laniel_francis@privacyrequired.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Daniel Axtens <dja@axtens.net> Cc: netdev@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> |
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4797632f4f |
string.h: Introduce memset_after() for wiping trailing members/padding
A common idiom in kernel code is to wipe the contents of a structure after a given member. This is especially useful in places where there is trailing padding. These open-coded cases are usually difficult to read and very sensitive to struct layout changes. Introduce a new helper, memset_after() that takes the target struct instance, the byte to write, and the member name after which the zeroing should start. Cc: Steffen Klassert <steffen.klassert@secunet.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Francis Laniel <laniel_francis@privacyrequired.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Daniel Axtens <dja@axtens.net> Cc: netdev@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> |
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c430f60036 |
fortify: Move remaining fortify helpers into fortify-string.h
When commit
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c0891ac15f |
isystem: ship and use stdarg.h
Ship minimal stdarg.h (1 type, 4 macros) as <linux/stdarg.h>. stdarg.h is the only userspace header commonly used in the kernel. GPL 2 version of <stdarg.h> can be extracted from http://archive.debian.org/debian/pool/main/g/gcc-4.2/gcc-4.2_4.2.4.orig.tar.gz Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> |
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4c52729377 |
kernel.h: split out kstrtox() and simple_strtox() to a separate header
kernel.h is being used as a dump for all kinds of stuff for a long time. Here is the attempt to start cleaning it up by splitting out kstrtox() and simple_strtox() helpers. At the same time convert users in header and lib folders to use new header. Though for time being include new header back to kernel.h to avoid twisted indirected includes for existing users. [andy.shevchenko@gmail.com: fix documentation references] Link: https://lkml.kernel.org/r/20210615220003.377901-1-andy.shevchenko@gmail.com Link: https://lkml.kernel.org/r/20210611185815.44103-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Francis Laniel <laniel_francis@privacyrequired.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Kars Mulder <kerneldev@karsmulder.nl> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Anna Schumaker <anna.schumaker@netapp.com> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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a28a6e860c |
string.h: move fortified functions definitions in a dedicated header.
This patch adds fortify-string.h to contain fortified functions definitions. Thus, the code is more separated and compile time is approximately 1% faster for people who do not set CONFIG_FORTIFY_SOURCE. Link: https://lkml.kernel.org/r/20210111092141.22946-1-laniel_francis@privacyrequired.com Link: https://lkml.kernel.org/r/20210111092141.22946-2-laniel_francis@privacyrequired.com Signed-off-by: Francis Laniel <laniel_francis@privacyrequired.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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0fea6e9af8 |
kasan, arm64: expand CONFIG_KASAN checks
Some #ifdef CONFIG_KASAN checks are only relevant for software KASAN modes (either related to shadow memory or compiler instrumentation). Expand those into CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS. Link: https://lkml.kernel.org/r/e6971e432dbd72bb897ff14134ebb7e169bdcf0c.1606161801.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Alexander Potapenko <glider@google.com> Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Branislav Rankov <Branislav.Rankov@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Marco Elver <elver@google.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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33e56a59e6 |
string.h: add FORTIFY coverage for strscpy()
The fortified version of strscpy ensures the following before vanilla strscpy is called: 1. There is no read overflow because we either size is smaller than src length or we shrink size to src length by calling fortified strnlen. 2. There is no write overflow because we either failed during compilation or at runtime by checking that size is smaller than dest size. Link: https://lkml.kernel.org/r/20201122162451.27551-4-laniel_francis@privacyrequired.com Signed-off-by: Francis Laniel <laniel_francis@privacyrequired.com> Acked-by: Kees Cook <keescook@chromium.org> Cc: Daniel Axtens <dja@axtens.net> Cc: Daniel Micay <danielmicay@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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6a39e62abb |
lib: string.h: detect intra-object overflow in fortified string functions
Patch series "Fortify strscpy()", v7.
This patch implements a fortified version of strscpy() enabled by setting
CONFIG_FORTIFY_SOURCE=y. The new version ensures the following before
calling vanilla strscpy():
1. There is no read overflow because either size is smaller than src
length or we shrink size to src length by calling fortified strnlen().
2. There is no write overflow because we either failed during
compilation or at runtime by checking that size is smaller than dest
size. Note that, if src and dst size cannot be got, the patch defaults
to call vanilla strscpy().
The patches adds the following:
1. Implement the fortified version of strscpy().
2. Add a new LKDTM test to ensures the fortified version still returns
the same value as the vanilla one while panic'ing when there is a write
overflow.
3. Correct some typos in LKDTM related file.
I based my modifications on top of two patches from Daniel Axtens which
modify calls to __builtin_object_size, in fortified string functions, to
ensure the true size of char * are returned and not the surrounding
structure size.
About performance, I measured the slow down of fortified strscpy(), using
the vanilla one as baseline. The hardware I used is an Intel i3 2130 CPU
clocked at 3.4 GHz. I ran "Linux 5.10.0-rc4+ SMP PREEMPT" inside qemu
3.10 with 4 CPU cores. The following code, called through LKDTM, was used
as a benchmark:
#define TIMES 10000
char *src;
char dst[7];
int i;
ktime_t begin;
src = kstrdup("foobar", GFP_KERNEL);
if (src == NULL)
return;
begin = ktime_get();
for (i = 0; i < TIMES; i++)
strscpy(dst, src, strlen(src));
pr_info("%d fortified strscpy() tooks %lld", TIMES, ktime_get() - begin);
begin = ktime_get();
for (i = 0; i < TIMES; i++)
__real_strscpy(dst, src, strlen(src));
pr_info("%d vanilla strscpy() tooks %lld", TIMES, ktime_get() - begin);
kfree(src);
I called the above code 30 times to compute stats for each version (in ns,
round to int):
| version | mean | std | median | 95th |
| --------- | ------- | ------ | ------- | ------- |
| fortified | 245_069 | 54_657 | 216_230 | 331_122 |
| vanilla | 172_501 | 70_281 | 143_539 | 219_553 |
On average, fortified strscpy() is approximately 1.42 times slower than
vanilla strscpy(). For the 95th percentile, the fortified version is
about 1.50 times slower.
So, clearly the stats are not in favor of fortified strscpy(). But, the
fortified version loops the string twice (one in strnlen() and another in
vanilla strscpy()) while the vanilla one only loops once. This can
explain why fortified strscpy() is slower than the vanilla one.
This patch (of 5):
When the fortify feature was first introduced in commit
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ec6347bb43 |
x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()
In reaction to a proposal to introduce a memcpy_mcsafe_fast() implementation Linus points out that memcpy_mcsafe() is poorly named relative to communicating the scope of the interface. Specifically what addresses are valid to pass as source, destination, and what faults / exceptions are handled. Of particular concern is that even though x86 might be able to handle the semantics of copy_mc_to_user() with its common copy_user_generic() implementation other archs likely need / want an explicit path for this case: On Fri, May 1, 2020 at 11:28 AM Linus Torvalds <torvalds@linux-foundation.org> wrote: > > On Thu, Apr 30, 2020 at 6:21 PM Dan Williams <dan.j.williams@intel.com> wrote: > > > > However now I see that copy_user_generic() works for the wrong reason. > > It works because the exception on the source address due to poison > > looks no different than a write fault on the user address to the > > caller, it's still just a short copy. So it makes copy_to_user() work > > for the wrong reason relative to the name. > > Right. > > And it won't work that way on other architectures. On x86, we have a > generic function that can take faults on either side, and we use it > for both cases (and for the "in_user" case too), but that's an > artifact of the architecture oddity. > > In fact, it's probably wrong even on x86 - because it can hide bugs - > but writing those things is painful enough that everybody prefers > having just one function. Replace a single top-level memcpy_mcsafe() with either copy_mc_to_user(), or copy_mc_to_kernel(). Introduce an x86 copy_mc_fragile() name as the rename for the low-level x86 implementation formerly named memcpy_mcsafe(). It is used as the slow / careful backend that is supplanted by a fast copy_mc_generic() in a follow-on patch. One side-effect of this reorganization is that separating copy_mc_64.S to its own file means that perf no longer needs to track dependencies for its memcpy_64.S benchmarks. [ bp: Massage a bit. ] Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: <stable@vger.kernel.org> Link: http://lore.kernel.org/r/CAHk-=wjSqtXAqfUJxFtWNwmguFASTgB0dz1dT3V-78Quiezqbg@mail.gmail.com Link: https://lkml.kernel.org/r/160195561680.2163339.11574962055305783722.stgit@dwillia2-desk3.amr.corp.intel.com |
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47227d27e2 |
string.h: fix incompatibility between FORTIFY_SOURCE and KASAN
The memcmp KASAN self-test fails on a kernel with both KASAN and FORTIFY_SOURCE. When FORTIFY_SOURCE is on, a number of functions are replaced with fortified versions, which attempt to check the sizes of the operands. However, these functions often directly invoke __builtin_foo() once they have performed the fortify check. Using __builtins may bypass KASAN checks if the compiler decides to inline it's own implementation as sequence of instructions, rather than emit a function call that goes out to a KASAN-instrumented implementation. Why is only memcmp affected? ============================ Of the string and string-like functions that kasan_test tests, only memcmp is replaced by an inline sequence of instructions in my testing on x86 with gcc version 9.2.1 20191008 (Ubuntu 9.2.1-9ubuntu2). I believe this is due to compiler heuristics. For example, if I annotate kmalloc calls with the alloc_size annotation (and disable some fortify compile-time checking!), the compiler will replace every memset except the one in kmalloc_uaf_memset with inline instructions. (I have some WIP patches to add this annotation.) Does this affect other functions in string.h? ============================================= Yes. Anything that uses __builtin_* rather than __real_* could be affected. This looks like: - strncpy - strcat - strlen - strlcpy maybe, under some circumstances? - strncat under some circumstances - memset - memcpy - memmove - memcmp (as noted) - memchr - strcpy Whether a function call is emitted always depends on the compiler. Most bugs should get caught by FORTIFY_SOURCE, but the missed memcmp test shows that this is not always the case. Isn't FORTIFY_SOURCE disabled with KASAN? ========================================- The string headers on all arches supporting KASAN disable fortify with kasan, but only when address sanitisation is _also_ disabled. For example from x86: #if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__) /* * For files that are not instrumented (e.g. mm/slub.c) we * should use not instrumented version of mem* functions. */ #define memcpy(dst, src, len) __memcpy(dst, src, len) #define memmove(dst, src, len) __memmove(dst, src, len) #define memset(s, c, n) __memset(s, c, n) #ifndef __NO_FORTIFY #define __NO_FORTIFY /* FORTIFY_SOURCE uses __builtin_memcpy, etc. */ #endif #endif This comes from commit |
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0bee0cece2 |
lib/string: add strnchrnul()
Patch series "lib: rework bitmap_parse", v5. Similarl to the recently revisited bitmap_parselist(), bitmap_parse() is ineffective and overcomplicated. This series reworks it, aligns its interface with bitmap_parselist() and makes it simpler to use. The series also adds a test for the function and fixes usage of it in cpumask_parse() according to the new design - drops the calculating of length of an input string. bitmap_parse() takes the array of numbers to be put into the map in the BE order which is reversed to the natural LE order for bitmaps. For example, to construct bitmap containing a bit on the position 42, we have to put a line '400,0'. Current implementation reads chunk one by one from the beginning ('400' before '0') and makes bitmap shift after each successful parse. It makes the complexity of the whole process as O(n^2). We can do it in reverse direction ('0' before '400') and avoid shifting, but it requires reverse parsing helpers. This patch (of 7): New function works like strchrnul() with a length limited string. Link: http://lkml.kernel.org/r/20200102043031.30357-2-yury.norov@gmail.com Signed-off-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Amritha Nambiar <amritha.nambiar@intel.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: "Tobin C . Harding" <tobin@kernel.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Cc: Vineet Gupta <vineet.gupta1@synopsys.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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e4dcad204d |
rss_stat: add support to detect RSS updates of external mm
When a process updates the RSS of a different process, the rss_stat tracepoint appears in the context of the process doing the update. This can confuse userspace that the RSS of process doing the update is updated, while in reality a different process's RSS was updated. This issue happens in reclaim paths such as with direct reclaim or background reclaim. This patch adds more information to the tracepoint about whether the mm being updated belongs to the current process's context (curr field). We also include a hash of the mm pointer so that the process who the mm belongs to can be uniquely identified (mm_id field). Also vsprintf.c is refactored a bit to allow reuse of hashing code. [akpm@linux-foundation.org: remove unused local `str'] [joelaf@google.com: inline call to ptr_to_hashval] Link: http://lore.kernel.org/r/20191113153816.14b95acd@gandalf.local.home Link: http://lkml.kernel.org/r/20191114164622.GC233237@google.com Link: http://lkml.kernel.org/r/20191106024452.81923-1-joel@joelfernandes.org Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Reported-by: Ioannis Ilkos <ilkos@google.com> Acked-by: Petr Mladek <pmladek@suse.com> [lib/vsprintf.c] Cc: Tim Murray <timmurray@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Carmen Jackson <carmenjackson@google.com> Cc: Mayank Gupta <mayankgupta@google.com> Cc: Daniel Colascione <dancol@google.com> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Minchan Kim <minchan@kernel.org> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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bec5007770 |
lib/string: Make memzero_explicit() inline instead of external
With the use of the barrier implied by barrier_data(), there is no need
for memzero_explicit() to be extern. Making it inline saves the overhead
of a function call, and allows the code to be reused in arch/*/purgatory
without having to duplicate the implementation.
Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H . Peter Anvin <hpa@zytor.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephan Mueller <smueller@chronox.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-crypto@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Fixes:
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917cda2790 |
kernel-doc: core-api: include string.h into core-api
core-api should show all the various string functions including the newly added stracpy and stracpy_pad. Miscellanea: o Update the Returns: value for strscpy o fix a defect with %NUL) [joe@perches.com: correct return of -E2BIG descriptions] Link: http://lkml.kernel.org/r/29f998b4c1a9d69fbeae70500ba0daa4b340c546.1563889130.git.joe@perches.com Link: http://lkml.kernel.org/r/224a6ebf39955f4107c0c376d66155d970e46733.1563841972.git.joe@perches.com Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Stephen Kitt <steve@sk2.org> Cc: Nitin Gote <nitin.r.gote@intel.com> Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Cc: Jann Horn <jannh@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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458a3bf82d |
lib/string: Add strscpy_pad() function
We have a function to copy strings safely and we have a function to copy strings and zero the tail of the destination (if source string is shorter than destination buffer) but we do not have a function to do both at once. This means developers must write this themselves if they desire this functionality. This is a chore, and also leaves us open to off by one errors unnecessarily. Add a function that calls strscpy() then memset()s the tail to zero if the source string is shorter than the destination buffer. Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Tobin C. Harding <tobin@kernel.org> Signed-off-by: Shuah Khan <shuah@kernel.org> |
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5f074f3e19 |
lib/string.c: implement a basic bcmp
A recent optimization in Clang (r355672) lowers comparisons of the
return value of memcmp against zero to comparisons of the return value
of bcmp against zero. This helps some platforms that implement bcmp
more efficiently than memcmp. glibc simply aliases bcmp to memcmp, but
an optimized implementation is in the works.
This results in linkage failures for all targets with Clang due to the
undefined symbol. For now, just implement bcmp as a tailcail to memcmp
to unbreak the build. This routine can be further optimized in the
future.
Other ideas discussed:
* A weak alias was discussed, but breaks for architectures that define
their own implementations of memcmp since aliases to declarations are
not permitted (only definitions). Arch-specific memcmp
implementations typically declare memcmp in C headers, but implement
them in assembly.
* -ffreestanding also is used sporadically throughout the kernel.
* -fno-builtin-bcmp doesn't work when doing LTO.
Link: https://bugs.llvm.org/show_bug.cgi?id=41035
Link: https://code.woboq.org/userspace/glibc/string/memcmp.c.html#bcmp
Link:
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