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2024-07-02ARM: 9407/1: Add support for STACKLEAK gcc pluginJinjie Ruan1-0/+1
Add the STACKLEAK gcc plugin to arm32 by adding the helper used by stackleak common code: on_thread_stack(). It initialize the stack with the poison value before returning from system calls which improves the kernel security. Additionally, this disables the plugin in EFI stub code and decompress code, which are out of scope for the protection. Before the test on Qemu versatilepb board: # echo STACKLEAK_ERASING > /sys/kernel/debug/provoke-crash/DIRECT lkdtm: Performing direct entry STACKLEAK_ERASING lkdtm: XFAIL: stackleak is not supported on this arch (HAVE_ARCH_STACKLEAK=n) After: # echo STACKLEAK_ERASING > /sys/kernel/debug/provoke-crash/DIRECT lkdtm: Performing direct entry STACKLEAK_ERASING lkdtm: stackleak stack usage: high offset: 80 bytes current: 280 bytes lowest: 696 bytes tracked: 696 bytes untracked: 192 bytes poisoned: 7220 bytes low offset: 4 bytes lkdtm: OK: the rest of the thread stack is properly erased Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2024-06-10ARM: 9404/1: arm32: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATIONYuntao Liu1-1/+1
The current arm32 architecture does not yet support the HAVE_LD_DEAD_CODE_DATA_ELIMINATION feature. arm32 is widely used in embedded scenarios, and enabling this feature would be beneficial for reducing the size of the kernel image. In order to make this work, we keep the necessary tables by annotating them with KEEP, also it requires further changes to linker script to KEEP some tables and wildcard compiler generated sections into the right place. When using ld.lld for linking, KEEP is not recognized within the OVERLAY command, and Ard proposed a concise method to solve this problem. It boots normally with defconfig, vexpress_defconfig and tinyconfig. The size comparison of zImage is as follows: defconfig vexpress_defconfig tinyconfig 5137712 5138024 424192 no dce 5032560 4997824 298384 dce 2.0% 2.7% 29.7% shrink When using smaller config file, there is a significant reduction in the size of the zImage. We also tested this patch on a commercially available single-board computer, and the comparison is as follows: a15eb_config 2161384 no dce 2092240 dce 3.2% shrink The zImage size has been reduced by approximately 3.2%, which is 70KB on 2.1M. Signed-off-by: Yuntao Liu <liuyuntao12@huawei.com> Tested-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2024-05-14Makefile: remove redundant tool coverage variablesMasahiro Yamada1-7/+0
Now Kbuild provides reasonable defaults for objtool, sanitizers, and profilers. Remove redundant variables. Note: This commit changes the coverage for some objects: - include arch/mips/vdso/vdso-image.o into UBSAN, GCOV, KCOV - include arch/sparc/vdso/vdso-image-*.o into UBSAN - include arch/sparc/vdso/vma.o into UBSAN - include arch/x86/entry/vdso/extable.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vdso-image-*.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vdso32-setup.o into KASAN, KCSAN, UBSAN, GCOV, KCOV - include arch/x86/entry/vdso/vma.o into GCOV, KCOV - include arch/x86/um/vdso/vma.o into KASAN, GCOV, KCOV I believe these are positive effects because all of them are kernel space objects. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Roberto Sassu <roberto.sassu@huawei.com>
2024-03-01fortify: Improve buffer overflow reportingKees Cook2-2/+2
Improve the reporting of buffer overflows under CONFIG_FORTIFY_SOURCE to help accelerate debugging efforts. The calculations are all just sitting in registers anyway, so pass them along to the function to be reported. For example, before: detected buffer overflow in memcpy and after: memcpy: detected buffer overflow: 4096 byte read of buffer size 1 Link: https://lore.kernel.org/r/20230407192717.636137-10-keescook@chromium.org Signed-off-by: Kees Cook <keescook@chromium.org>
2024-03-01fortify: Split reporting and avoid passing string pointerKees Cook2-2/+2
In preparation for KUnit testing and further improvements in fortify failure reporting, split out the report and encode the function and access failure (read or write overflow) into a single u8 argument. This mainly ends up saving a tiny bit of space in the data segment. For a defconfig with FORTIFY_SOURCE enabled: $ size gcc/vmlinux.before gcc/vmlinux.after text data bss dec hex filename 26132309 9760658 2195460 38088427 2452eeb gcc/vmlinux.before 26132386 9748382 2195460 38076228 244ff44 gcc/vmlinux.after Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2023-06-19ARM: 9311/1: decompressor: move function prototypes to misc.hArnd Bergmann4-6/+13
A number of prototypes are missing for the decompressor, some of them are in the .c files that contain the callers, but are invisible at the function definition: arch/arm/boot/compressed/misc.c:129:17: error: no previous prototype for '__div0' [-Werror=missing-prototypes] arch/arm/boot/compressed/misc.c:138:1: error: no previous prototype for 'decompress_kernel' [-Werror=missing-prototypes] arch/arm/boot/compressed/misc.c:163:6: error: no previous prototype for 'fortify_panic' [-Werror=missing-prototypes] arch/arm/boot/compressed/decompress.c:63:5: error: no previous prototype for 'do_decompress' [-Werror=missing-prototypes] arch/arm/boot/compressed/fdt_check_mem_start.c:63:10: error: no previous prototype for 'fdt_check_mem_start' [-Werror=missing-prototypes] Move these all to misc.h so they are visible by the callee as well. Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2023-04-28Merge tag 'modules-6.4-rc1' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull module updates from Luis Chamberlain: "The summary of the changes for this pull requests is: - Song Liu's new struct module_memory replacement - Nick Alcock's MODULE_LICENSE() removal for non-modules - My cleanups and enhancements to reduce the areas where we vmalloc module memory for duplicates, and the respective debug code which proves the remaining vmalloc pressure comes from userspace. Most of the changes have been in linux-next for quite some time except the minor fixes I made to check if a module was already loaded prior to allocating the final module memory with vmalloc and the respective debug code it introduces to help clarify the issue. Although the functional change is small it is rather safe as it can only *help* reduce vmalloc space for duplicates and is confirmed to fix a bootup issue with over 400 CPUs with KASAN enabled. I don't expect stable kernels to pick up that fix as the cleanups would have also had to have been picked up. Folks on larger CPU systems with modules will want to just upgrade if vmalloc space has been an issue on bootup. Given the size of this request, here's some more elaborate details: The functional change change in this pull request is the very first patch from Song Liu which replaces the 'struct module_layout' with a new 'struct module_memory'. The old data structure tried to put together all types of supported module memory types in one data structure, the new one abstracts the differences in memory types in a module to allow each one to provide their own set of details. This paves the way in the future so we can deal with them in a cleaner way. If you look at changes they also provide a nice cleanup of how we handle these different memory areas in a module. This change has been in linux-next since before the merge window opened for v6.3 so to provide more than a full kernel cycle of testing. It's a good thing as quite a bit of fixes have been found for it. Jason Baron then made dynamic debug a first class citizen module user by using module notifier callbacks to allocate / remove module specific dynamic debug information. Nick Alcock has done quite a bit of work cross-tree to remove module license tags from things which cannot possibly be module at my request so to: a) help him with his longer term tooling goals which require a deterministic evaluation if a piece a symbol code could ever be part of a module or not. But quite recently it is has been made clear that tooling is not the only one that would benefit. Disambiguating symbols also helps efforts such as live patching, kprobes and BPF, but for other reasons and R&D on this area is active with no clear solution in sight. b) help us inch closer to the now generally accepted long term goal of automating all the MODULE_LICENSE() tags from SPDX license tags In so far as a) is concerned, although module license tags are a no-op for non-modules, tools which would want create a mapping of possible modules can only rely on the module license tag after the commit 8b41fc4454e ("kbuild: create modules.builtin without Makefile.modbuiltin or tristate.conf"). Nick has been working on this *for years* and AFAICT I was the only one to suggest two alternatives to this approach for tooling. The complexity in one of my suggested approaches lies in that we'd need a possible-obj-m and a could-be-module which would check if the object being built is part of any kconfig build which could ever lead to it being part of a module, and if so define a new define -DPOSSIBLE_MODULE [0]. A more obvious yet theoretical approach I've suggested would be to have a tristate in kconfig imply the same new -DPOSSIBLE_MODULE as well but that means getting kconfig symbol names mapping to modules always, and I don't think that's the case today. I am not aware of Nick or anyone exploring either of these options. Quite recently Josh Poimboeuf has pointed out that live patching, kprobes and BPF would benefit from resolving some part of the disambiguation as well but for other reasons. The function granularity KASLR (fgkaslr) patches were mentioned but Joe Lawrence has clarified this effort has been dropped with no clear solution in sight [1]. In the meantime removing module license tags from code which could never be modules is welcomed for both objectives mentioned above. Some developers have also welcomed these changes as it has helped clarify when a module was never possible and they forgot to clean this up, and so you'll see quite a bit of Nick's patches in other pull requests for this merge window. I just picked up the stragglers after rc3. LWN has good coverage on the motivation behind this work [2] and the typical cross-tree issues he ran into along the way. The only concrete blocker issue he ran into was that we should not remove the MODULE_LICENSE() tags from files which have no SPDX tags yet, even if they can never be modules. Nick ended up giving up on his efforts due to having to do this vetting and backlash he ran into from folks who really did *not understand* the core of the issue nor were providing any alternative / guidance. I've gone through his changes and dropped the patches which dropped the module license tags where an SPDX license tag was missing, it only consisted of 11 drivers. To see if a pull request deals with a file which lacks SPDX tags you can just use: ./scripts/spdxcheck.py -f \ $(git diff --name-only commid-id | xargs echo) You'll see a core module file in this pull request for the above, but that's not related to his changes. WE just need to add the SPDX license tag for the kernel/module/kmod.c file in the future but it demonstrates the effectiveness of the script. Most of Nick's changes were spread out through different trees, and I just picked up the slack after rc3 for the last kernel was out. Those changes have been in linux-next for over two weeks. The cleanups, debug code I added and final fix I added for modules were motivated by David Hildenbrand's report of boot failing on a systems with over 400 CPUs when KASAN was enabled due to running out of virtual memory space. Although the functional change only consists of 3 lines in the patch "module: avoid allocation if module is already present and ready", proving that this was the best we can do on the modules side took quite a bit of effort and new debug code. The initial cleanups I did on the modules side of things has been in linux-next since around rc3 of the last kernel, the actual final fix for and debug code however have only been in linux-next for about a week or so but I think it is worth getting that code in for this merge window as it does help fix / prove / evaluate the issues reported with larger number of CPUs. Userspace is not yet fixed as it is taking a bit of time for folks to understand the crux of the issue and find a proper resolution. Worst come to worst, I have a kludge-of-concept [3] of how to make kernel_read*() calls for modules unique / converge them, but I'm currently inclined to just see if userspace can fix this instead" Link: https://lore.kernel.org/all/Y/kXDqW+7d71C4wz@bombadil.infradead.org/ [0] Link: https://lkml.kernel.org/r/025f2151-ce7c-5630-9b90-98742c97ac65@redhat.com [1] Link: https://lwn.net/Articles/927569/ [2] Link: https://lkml.kernel.org/r/20230414052840.1994456-3-mcgrof@kernel.org [3] * tag 'modules-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (121 commits) module: add debugging auto-load duplicate module support module: stats: fix invalid_mod_bytes typo module: remove use of uninitialized variable len module: fix building stats for 32-bit targets module: stats: include uapi/linux/module.h module: avoid allocation if module is already present and ready module: add debug stats to help identify memory pressure module: extract patient module check into helper modules/kmod: replace implementation with a semaphore Change DEFINE_SEMAPHORE() to take a number argument module: fix kmemleak annotations for non init ELF sections module: Ignore L0 and rename is_arm_mapping_symbol() module: Move is_arm_mapping_symbol() to module_symbol.h module: Sync code of is_arm_mapping_symbol() scripts/gdb: use mem instead of core_layout to get the module address interconnect: remove module-related code interconnect: remove MODULE_LICENSE in non-modules zswap: remove MODULE_LICENSE in non-modules zpool: remove MODULE_LICENSE in non-modules x86/mm/dump_pagetables: remove MODULE_LICENSE in non-modules ...
2023-04-11ARM: 9291/1: decompressor: simplify the path to the top vmlinuxMasahiro Yamada1-1/+1
With commit 8debed3efe3a ("kbuild: export top-level LDFLAGS_vmlinux only to scripts/Makefile.vmlinux") applied, we no longer see the error message while building the ARM zImage, but we do not have a good reason to complicate the file path either. '$(obj)/../../../../vmlinux' is canonicalized to 'vmlinux'. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2023-03-10ARM: dyndbg: allow including dyndbg.h in decompressorArnd Bergmann1-0/+1
After a change to linux/module.h, dyndbg.h is now included indirectly from the decompressor for lz4 support, which in turn causes a build failure on 32-bit Arm: In file included from include/linux/module.h:30, from arch/arm/boot/compressed/../../../../lib/lz4/lz4_decompress.c:39, from arch/arm/boot/compressed/../../../../lib/decompress_unlz4.c:10, from arch/arm/boot/compressed/decompress.c:59: include/linux/dynamic_debug.h: In function 'ddebug_dyndbg_module_param_cb': include/linux/dynamic_debug.h:307:14: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration] 307 | if (!strcmp(param, "dyndbg")) { | ^~~~~~ include/linux/dynamic_debug.h:1:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'? +++ |+#include <string.h> The decompressor has its own replacement for the linux/string.h contents, so the normal declaration is not visible here. Since the function is not actually called, it is sufficient to add a declaration, and this is in fact the correct one as it matches the definition in arch/arm/boot/compressed/string.c. Fixes: 7deabd674988 ("dyndbg: use the module notifier callbacks") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Jason Baron <jbaron@akamai.com> Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-01-12ARM: sa1100: remove unused board filesArnd Bergmann1-4/+0
The Cerf, H3100, Badge4, Hackkit, LART, NanoEngine, PLEB, Shannon and Simpad machines were all marked as unused as there are no known users left. Remove all of these, along with references to them in defconfig files and drivers. Four machines remain now: Assabet, Collie (Zaurus SL5500), iPAQ H3600 and Jornada 720, each of which had one person still using them, with Collie also being supported in Qemu. Cc: Peter Chubb <peter.chubb@unsw.edu.au> Cc: Stefan Eletzhofer <stefan.eletzhofer@eletztrick.de> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Lee Jones <lee@kernel.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-01-11ARM: ep93xx: remove old board filesArnd Bergmann1-12/+1
These five board files were marked as unused a while ago, and nobody wanted to keep them around for longer, so remove them now. We still have the edb93xx, visision_ep9307 and ts72xx files, which can hopefully be converted to device tree in the future. Cc: Lennert Buytenhek <kernel@wantstofly.org> Cc: Hubert Feurstein <hubert.feurstein@contec.at> Acked-by: Alexander Sverdlin <alexander.sverdlin@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-12-14Merge tag 'hardening-v6.2-rc1' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull kernel hardening updates from Kees Cook: - Convert flexible array members, fix -Wstringop-overflow warnings, and fix KCFI function type mismatches that went ignored by maintainers (Gustavo A. R. Silva, Nathan Chancellor, Kees Cook) - Remove the remaining side-effect users of ksize() by converting dma-buf, btrfs, and coredump to using kmalloc_size_roundup(), add more __alloc_size attributes, and introduce full testing of all allocator functions. Finally remove the ksize() side-effect so that each allocation-aware checker can finally behave without exceptions - Introduce oops_limit (default 10,000) and warn_limit (default off) to provide greater granularity of control for panic_on_oops and panic_on_warn (Jann Horn, Kees Cook) - Introduce overflows_type() and castable_to_type() helpers for cleaner overflow checking - Improve code generation for strscpy() and update str*() kern-doc - Convert strscpy and sigphash tests to KUnit, and expand memcpy tests - Always use a non-NULL argument for prepare_kernel_cred() - Disable structleak plugin in FORTIFY KUnit test (Anders Roxell) - Adjust orphan linker section checking to respect CONFIG_WERROR (Xin Li) - Make sure siginfo is cleared for forced SIGKILL (haifeng.xu) - Fix um vs FORTIFY warnings for always-NULL arguments * tag 'hardening-v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (31 commits) ksmbd: replace one-element arrays with flexible-array members hpet: Replace one-element array with flexible-array member um: virt-pci: Avoid GCC non-NULL warning signal: Initialize the info in ksignal lib: fortify_kunit: build without structleak plugin panic: Expose "warn_count" to sysfs panic: Introduce warn_limit panic: Consolidate open-coded panic_on_warn checks exit: Allow oops_limit to be disabled exit: Expose "oops_count" to sysfs exit: Put an upper limit on how often we can oops panic: Separate sysctl logic from CONFIG_SMP mm/pgtable: Fix multiple -Wstringop-overflow warnings mm: Make ksize() a reporting-only function kunit/fortify: Validate __alloc_size attribute results drm/sti: Fix return type of sti_{dvo,hda,hdmi}_connector_mode_valid() drm/fsl-dcu: Fix return type of fsl_dcu_drm_connector_mode_valid() driver core: Add __alloc_size hint to devm allocators overflow: Introduce overflows_type() and castable_to_type() coredump: Proactively round up to kmalloc bucket size ...
2022-12-14Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds1-1/+1
Pull ARM updates from Russell King: - update unwinder to cope with module PLTs - enable UBSAN on ARM - improve kernel fault message - update UEFI runtime page tables dump - avoid clang's __aeabi_uldivmod generated in NWFPE code - disable FIQs on CPU shutdown paths - update XOR register usage - a number of build updates (using .arch, thread pointer, removal of lazy evaluation in Makefile) - conversion of stacktrace code to stackwalk - findbit assembly updates - hwcap feature updates for ARMv8 CPUs - instruction dump updates for big-endian platforms - support for function error injection * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (31 commits) ARM: 9279/1: support function error injection ARM: 9277/1: Make the dumped instructions are consistent with the disassembled ones ARM: 9276/1: Refactor dump_instr() ARM: 9275/1: Drop '-mthumb' from AFLAGS_ISA ARM: 9274/1: Add hwcap for Speculative Store Bypassing Safe ARM: 9273/1: Add hwcap for Speculation Barrier(SB) ARM: 9272/1: vfp: Add hwcap for FEAT_AA32I8MM ARM: 9271/1: vfp: Add hwcap for FEAT_AA32BF16 ARM: 9270/1: vfp: Add hwcap for FEAT_FHM ARM: 9269/1: vfp: Add hwcap for FEAT_DotProd ARM: 9268/1: vfp: Add hwcap FPHP and ASIMDHP for FEAT_FP16 ARM: 9267/1: Define Armv8 registers in AArch32 state ARM: findbit: add unwinder information ARM: findbit: operate by words ARM: findbit: convert to macros ARM: findbit: provide more efficient ARMv7 implementation ARM: findbit: document ARMv5 bit offset calculation ARM: 9259/1: stacktrace: Convert stacktrace to generic ARCH_STACKWALK ARM: 9258/1: stacktrace: Make stack walk callback consistent with generic code ARM: 9265/1: pass -march= only to compiler ...
2022-11-08ARM: 9263/1: use .arch directives instead of assembler command line flagsNick Desaulniers1-1/+0
Similar to commit a6c30873ee4a ("ARM: 8989/1: use .fpu assembler directives instead of assembler arguments"). GCC and GNU binutils support setting the "sub arch" via -march=, -Wa,-march, target function attribute, and .arch assembler directive. Clang was missing support for -Wa,-march=, but this was implemented in clang-13. The behavior of both GCC and Clang is to prefer -Wa,-march= over -march= for assembler and assembler-with-cpp sources, but Clang will warn about the -march= being unused. clang: warning: argument unused during compilation: '-march=armv6k' [-Wunused-command-line-argument] Since most assembler is non-conditionally assembled with one sub arch (modulo arch/arm/delay-loop.S which conditionally is assembled as armv4 based on CONFIG_ARCH_RPC, and arch/arm/mach-at91/pm-suspend.S which is conditionally assembled as armv7-a based on CONFIG_CPU_V7), prefer the .arch assembler directive. Add a few more instances found in compile testing as found by Arnd and Nathan. Link: https://github.com/llvm/llvm-project/commit/1d51c699b9e2ebc5bcfdbe85c74cc871426333d4 Link: https://bugs.llvm.org/show_bug.cgi?id=48894 Link: https://github.com/ClangBuiltLinux/linux/issues/1195 Link: https://github.com/ClangBuiltLinux/linux/issues/1315 Suggested-by: Arnd Bergmann <arnd@arndb.de> Suggested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2022-11-07ARM: 9253/1: ubsan: select ARCH_HAS_UBSAN_SANITIZE_ALLSeung-Woo Kim1-0/+1
To enable UBSAN on ARM, this patch enables ARCH_HAS_UBSAN_SANITIZE_ALL from arm confiuration. Basic kernel bootup test is passed on arm with CONFIG_UBSAN_SANITIZE_ALL enabled. [florian: rebased against v6.0-rc7] Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2022-11-01kbuild: upgrade the orphan section warning to an error if CONFIG_WERROR is setXin Li1-1/+1
Andrew Cooper suggested upgrading the orphan section warning to a hard link error. However Nathan Chancellor said outright turning the warning into an error with no escape hatch might be too aggressive, as we have had these warnings triggered by new compiler generated sections, and suggested turning orphan sections into an error only if CONFIG_WERROR is set. Kees Cook echoed and emphasized that the mandate from Linus is that we should avoid breaking builds. It wrecks bisection, it causes problems across compiler versions, etc. Thus upgrade the orphan section warning to a hard link error only if CONFIG_WERROR is set. Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com> Suggested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Xin Li <xin3.li@intel.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20221025073023.16137-2-xin3.li@intel.com
2022-10-06Merge tag 'arm-drivers-6.1' of ↵Linus Torvalds1-4/+0
git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc Pull ARM driver updates from Arnd Bergmann: "The drivers branch for 6.1 is a bit larger than for most releases. Most of the changes come from SoC maintainers for the drivers/soc subsystem: - A new driver for error handling on the NVIDIA Tegra 'control backbone' bus. - A new driver for Qualcomm LLCC/DDR bandwidth measurement - New Rockchip rv1126 and rk3588 power domain drivers - DT binding updates for memory controllers, older Rockchip SoCs, various Mediatek devices, Qualcomm SCM firmware - Minor updates to Hisilicon LPC bus, the Allwinner SRAM driver, the Apple rtkit firmware driver, Tegra firmware - Minor updates for SoC drivers (Samsung, Mediatek, Renesas, Tegra, Qualcomm, Broadcom, NXP, ...) There are also some separate subsystem with downstream maintainers that merge updates this way: - Various updates and new drivers in the memory controller subsystem for Mediatek and Broadcom SoCs - Small set of changes in preparation to add support for FF-A v1.1 specification later, in the Arm FF-A firmware subsystem - debugfs support in the PSCI firmware subsystem" * tag 'arm-drivers-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (149 commits) ARM: remove check for CONFIG_DEBUG_LL_SER3 firmware/psci: Add debugfs support to ease debugging firmware/psci: Print a warning if PSCI doesn't accept PC mode dt-bindings: memory: snps,dw-umctl2-ddrc: Extend schema with IRQs/resets/clocks props dt-bindings: memory: snps,dw-umctl2-ddrc: Replace opencoded numbers with macros dt-bindings: memory: snps,dw-umctl2-ddrc: Use more descriptive device name dt-bindings: memory: synopsys,ddrc-ecc: Detach Zynq DDRC controller support soc: sunxi: sram: Add support for the D1 system control soc: sunxi: sram: Export the LDO control register soc: sunxi: sram: Save a pointer to the OF match data soc: sunxi: sram: Return void from the release function soc: apple: rtkit: Add apple_rtkit_poll soc: imx: add i.MX93 media blk ctrl driver soc: imx: add i.MX93 SRC power domain driver soc: imx: imx8m-blk-ctrl: Use genpd_xlate_onecell soc: imx: imx8mp-blk-ctrl: handle PCIe PHY resets soc: imx: imx8m-blk-ctrl: add i.MX8MP VPU blk ctrl soc: imx: add i.MX8MP HDMI blk ctrl HDCP/HRV_MWR soc: imx: add icc paths for i.MX8MP hsio/hdmi blk ctrl soc: imx: add icc paths for i.MX8MP media blk ctrl ...
2022-10-04Merge tag 'hardening-v6.1-rc1' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull kernel hardening updates from Kees Cook: "Most of the collected changes here are fixes across the tree for various hardening features (details noted below). The most notable new feature here is the addition of the memcpy() overflow warning (under CONFIG_FORTIFY_SOURCE), which is the next step on the path to killing the common class of "trivially detectable" buffer overflow conditions (i.e. on arrays with sizes known at compile time) that have resulted in many exploitable vulnerabilities over the years (e.g. BleedingTooth). This feature is expected to still have some undiscovered false positives. It's been in -next for a full development cycle and all the reported false positives have been fixed in their respective trees. All the known-bad code patterns we could find with Coccinelle are also either fixed in their respective trees or in flight. The commit message in commit 54d9469bc515 ("fortify: Add run-time WARN for cross-field memcpy()") for the feature has extensive details, but I'll repeat here that this is a warning _only_, and is not intended to actually block overflows (yet). The many patches fixing array sizes and struct members have been landing for several years now, and we're finally able to turn this on to find any remaining stragglers. Summary: Various fixes across several hardening areas: - loadpin: Fix verity target enforcement (Matthias Kaehlcke). - zero-call-used-regs: Add missing clobbers in paravirt (Bill Wendling). - CFI: clean up sparc function pointer type mismatches (Bart Van Assche). - Clang: Adjust compiler flag detection for various Clang changes (Sami Tolvanen, Kees Cook). - fortify: Fix warnings in arch-specific code in sh, ARM, and xen. Improvements to existing features: - testing: improve overflow KUnit test, introduce fortify KUnit test, add more coverage to LKDTM tests (Bart Van Assche, Kees Cook). - overflow: Relax overflow type checking for wider utility. New features: - string: Introduce strtomem() and strtomem_pad() to fill a gap in strncpy() replacement needs. - um: Enable FORTIFY_SOURCE support. - fortify: Enable run-time struct member memcpy() overflow warning" * tag 'hardening-v6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (27 commits) Makefile.extrawarn: Move -Wcast-function-type-strict to W=1 hardening: Remove Clang's enable flag for -ftrivial-auto-var-init=zero sparc: Unbreak the build x86/paravirt: add extra clobbers with ZERO_CALL_USED_REGS enabled x86/paravirt: clean up typos and grammaros fortify: Convert to struct vs member helpers fortify: Explicitly check bounds are compile-time constants x86/entry: Work around Clang __bdos() bug ARM: decompressor: Include .data.rel.ro.local fortify: Adjust KUnit test for modular build sh: machvec: Use char[] for section boundaries kunit/memcpy: Avoid pathological compile-time string size lib: Improve the is_signed_type() kunit test LoadPin: Require file with verity root digests to have a header dm: verity-loadpin: Only trust verity targets with enforcement LoadPin: Fix Kconfig doc about format of file with verity digests um: Enable FORTIFY_SOURCE lkdtm: Update tests for memcpy() run-time warnings fortify: Add run-time WARN for cross-field memcpy() fortify: Use SIZE_MAX instead of (size_t)-1 ...
2022-09-28ARM: remove check for CONFIG_DEBUG_LL_SER3Paul Bolle1-4/+0
A check for CONFIG_DEBUG_LL_SER3 was added in v2.5.43. But the related symbol DEBUG_LL_SER3 was already removed in v2.5.8. This check has always evaluated to false. Remove it. Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-09-22ARM: 9243/1: riscpc: Unbreak the buildBart Van Assche1-0/+2
This patch fixes the following build error: In file included from ./include/linux/io.h:13, from ./arch/arm/mach-rpc/include/mach/uncompress.h:9, from arch/arm/boot/compressed/misc.c:31: ./arch/arm/include/asm/io.h:85:22: error: conflicting types for ‘__raw_writeb’ 85 | #define __raw_writeb __raw_writeb | ^~~~~~~~~~~~ ./arch/arm/include/asm/io.h:86:20: note: in expansion of macro ‘__raw_writeb’ 86 | static inline void __raw_writeb(u8 val, volatile void __iomem *addr) | ^~~~~~~~~~~~ In file included from arch/arm/boot/compressed/misc.c:26: arch/arm/boot/compressed/misc-ep93xx.h:13:20: note: previous definition of ‘__raw_writeb’ was here 13 | static inline void __raw_writeb(unsigned char value, unsigned int ptr) | ^~~~~~~~~~~~ To: Russell King <linux@armlinux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: linux-arm-kernel@lists.infradead.org Fixes: 0361c7e504b1 ("ARM: ep93xx: multiplatform support") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2022-09-22ARM: decompressor: Include .data.rel.ro.localKees Cook1-0/+2
The .data.rel.ro.local section has the same semantics as .data.rel.ro here, so include it in the .rodata section of the decompressor. Additionally since the .printk_index section isn't usable outside of the core kernel, discard it in the decompressor. Avoids these warnings: arm-linux-gnueabi-ld: warning: orphan section `.data.rel.ro.local' from `arch/arm/boot/compressed/fdt_rw.o' being placed in section `.data.rel.ro.local' arm-linux-gnueabi-ld: warning: orphan section `.printk_index' from `arch/arm/boot/compressed/fdt_rw.o' being placed in section `.printk_index' Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/linux-mm/202209080545.qMIVj7YM-lkp@intel.com Cc: Russell King <linux@armlinux.org.uk> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Kees Cook <keescook@chromium.org>
2022-04-04ARM: ep93xx: multiplatform supportArnd Bergmann2-0/+90
With the clock support and the interrupts out of the way, ep93xx can be compiled into the same kernel image as the other ARMv4/v5 platforms. The last obstacle are the two workarounds for broken boot loaders that require us to re-initialize the ethernet controller and/or the watchdog on certain machines. Move this code into the decompressor sources directly, checking for each possibly affected machine individually. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2022-04-03Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds1-2/+2
Pull ARM fixes from Russell King: - avoid unnecessary rebuilds for library objects - fix return value of __setup handlers - fix invalid input check for "crashkernel=" kernel option - silence KASAN warnings in unwind_frame * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 9191/1: arm/stacktrace, kasan: Silence KASAN warnings in unwind_frame() ARM: 9190/1: kdump: add invalid input check for 'crashkernel=0' ARM: 9187/1: JIVE: fix return value of __setup handler ARM: 9189/1: decompressor: fix unneeded rebuilds of library objects
2022-03-31ARM: 9189/1: decompressor: fix unneeded rebuilds of library objectsMasahiro Yamada1-2/+2
Since commit 251cc826be7d ("ARM: 9154/1: decompressor: do not copy source files while building"), the following three are rebuilt every time. AS arch/arm/boot/compressed/lib1funcs.o AS arch/arm/boot/compressed/ashldi3.o AS arch/arm/boot/compressed/bswapsdi2.o Move the "OBJS += ..." line up so these objects are added to 'targets'. Fixes: 251cc826be7d ("ARM: 9154/1: decompressor: do not copy source files while building") Reported-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2022-03-24Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds2-12/+1
Pull ARM updates from Russell King: "Updates for IRQ stacks and virtually mapped stack support, and ftrace: - Support for IRQ and vmap'ed stacks This covers all the work related to implementing IRQ stacks and vmap'ed stacks for all 32-bit ARM systems that are currently supported by the Linux kernel, including RiscPC and Footbridge. It has been submitted for review in four different waves: - IRQ stacks support for v7 SMP systems [0] - vmap'ed stacks support for v7 SMP systems[1] - extending support for both IRQ stacks and vmap'ed stacks for all remaining configurations, including v6/v7 SMP multiplatform kernels and uniprocessor configurations including v7-M [2] - fixes and updates in [3] - ftrace fixes and cleanups Make all flavors of ftrace available on all builds, regardless of ISA choice, unwinder choice or compiler [4]: - use ADD not POP where possible - fix a couple of Thumb2 related issues - enable HAVE_FUNCTION_GRAPH_FP_TEST for robustness - enable the graph tracer with the EABI unwinder - avoid clobbering frame pointer registers to make Clang happy - Fixes for the above" [0] https://lore.kernel.org/linux-arm-kernel/20211115084732.3704393-1-ardb@kernel.org/ [1] https://lore.kernel.org/linux-arm-kernel/20211122092816.2865873-1-ardb@kernel.org/ [2] https://lore.kernel.org/linux-arm-kernel/20211206164659.1495084-1-ardb@kernel.org/ [3] https://lore.kernel.org/linux-arm-kernel/20220124174744.1054712-1-ardb@kernel.org/ [4] https://lore.kernel.org/linux-arm-kernel/20220203082204.1176734-1-ardb@kernel.org/ * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (62 commits) ARM: fix building NOMMU ARMv4/v5 kernels ARM: unwind: only permit stack switch when unwinding call_with_stack() ARM: Revert "unwind: dump exception stack from calling frame" ARM: entry: fix unwinder problems caused by IRQ stacks ARM: unwind: set frame.pc correctly for current-thread unwinding ARM: 9184/1: return_address: disable again for CONFIG_ARM_UNWIND=y ARM: 9183/1: unwind: avoid spurious warnings on bogus code addresses Revert "ARM: 9144/1: forbid ftrace with clang and thumb2_kernel" ARM: mach-bcm: disable ftrace in SMC invocation routines ARM: cacheflush: avoid clobbering the frame pointer ARM: kprobes: treat R7 as the frame pointer register in Thumb2 builds ARM: ftrace: enable the graph tracer with the EABI unwinder ARM: unwind: track location of LR value in stack frame ARM: ftrace: enable HAVE_FUNCTION_GRAPH_FP_TEST ARM: ftrace: avoid unnecessary literal loads ARM: ftrace: avoid redundant loads or clobbering IP ARM: ftrace: use trampolines to keep .init.text in branching range ARM: ftrace: use ADD not POP to counter PUSH at entry ARM: ftrace: ensure that ADR takes the Thumb bit into account ARM: make get_current() and __my_cpu_offset() __always_inline ...
2022-01-19Merge tag 'kbuild-v5.17' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Add new kconfig target 'make mod2noconfig', which will be useful to speed up the build and test iteration. - Raise the minimum supported version of LLVM to 11.0.0 - Refactor certs/Makefile - Change the format of include/config/auto.conf to stop double-quoting string type CONFIG options. - Fix ARCH=sh builds in dash - Separate compression macros for general purposes (cmd_bzip2 etc.) and the ones for decompressors (cmd_bzip2_with_size etc.) - Misc Makefile cleanups * tag 'kbuild-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits) kbuild: add cmd_file_size arch: decompressor: remove useless vmlinux.bin.all-y kbuild: rename cmd_{bzip2,lzma,lzo,lz4,xzkern,zstd22} kbuild: drop $(size_append) from cmd_zstd sh: rename suffix-y to suffix_y doc: kbuild: fix default in `imply` table microblaze: use built-in function to get CPU_{MAJOR,MINOR,REV} certs: move scripts/extract-cert to certs/ kbuild: do not quote string values in include/config/auto.conf kbuild: do not include include/config/auto.conf from shell scripts certs: simplify $(srctree)/ handling and remove config_filename macro kbuild: stop using config_filename in scripts/Makefile.modsign certs: remove misleading comments about GCC PR certs: refactor file cleaning certs: remove unneeded -I$(srctree) option for system_certificates.o certs: unify duplicated cmd_extract_certs and improve the log certs: use $< and $@ to simplify the key generation rule kbuild: remove headers_check stub kbuild: move headers_check.pl to usr/include/ certs: use if_changed to re-generate the key when the key type is changed ...
2022-01-13kbuild: rename cmd_{bzip2,lzma,lzo,lz4,xzkern,zstd22}Masahiro Yamada1-4/+4
GZIP-compressed files end with 4 byte data that represents the size of the original input. The decompressors (the self-extracting kernel) exploit it to know the vmlinux size beforehand. To mimic the GZIP's trailer, Kbuild provides cmd_{bzip2,lzma,lzo,lz4,xzkern,zstd22}. Unfortunately these macros are used everywhere despite the appended size data is only useful for the decompressors. There is no guarantee that such hand-crafted trailers are safely ignored. In fact, the kernel refuses compressed initramdfs with the garbage data. That is why usr/Makefile overrides size_append to make it no-op. To limit the use of such broken compressed files, this commit renames the existing macros as follows: cmd_bzip2 --> cmd_bzip2_with_size cmd_lzma --> cmd_lzma_with_size cmd_lzo --> cmd_lzo_with_size cmd_lz4 --> cmd_lz4_with_size cmd_xzkern --> cmd_xzkern_with_size cmd_zstd22 --> cmd_zstd22_with_size To keep the decompressors working, I updated the following Makefiles accordingly: arch/arm/boot/compressed/Makefile arch/h8300/boot/compressed/Makefile arch/mips/boot/compressed/Makefile arch/parisc/boot/compressed/Makefile arch/s390/boot/compressed/Makefile arch/sh/boot/compressed/Makefile arch/x86/boot/compressed/Makefile I reused the current macro names for the normal usecases; they produce the compressed data in the proper format. I did not touch the following: arch/arc/boot/Makefile arch/arm64/boot/Makefile arch/csky/boot/Makefile arch/mips/boot/Makefile arch/riscv/boot/Makefile arch/sh/boot/Makefile kernel/Makefile This means those Makefiles will stop appending the size data. I dropped the 'override size_append' hack from usr/Makefile. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nicolas Schier <n.schier@avm.de>
2021-12-17ARM: 9159/1: decompressor: Avoid UNPREDICTABLE NOP encodingAndre Przywara2-9/+16
In the decompressor's head.S we need to start with an instruction that is some kind of NOP, but also mimics as the PE/COFF header, when the kernel is linked as an UEFI application. The clever solution here is "tstne r0, #0x4d000", which in the worst case just clobbers the condition flags, and bears the magic "MZ" signature in the lowest 16 bits. However the encoding used (0x13105a4d) is actually not valid, since bits [15:12] are supposed to be 0 (written as "(0)" in the ARM ARM). Violating this is UNPREDICTABLE, and *can* trigger an UNDEFINED exception. Common Cortex cores seem to ignore those bits, but QEMU chooses to trap, so the code goes fishing because of a missing exception handler at this point. We are just saved by the fact that commonly (with -kernel or when running from U-Boot) the "Z" bit is set, so the instruction is never executed. See [0] for more details. To make things more robust and avoid UNPREDICTABLE behaviour in the kernel code, lets replace this with a "two-instruction NOP": The first instruction is an exclusive OR, the effect of which the second instruction reverts. This does not leave any trace, neither in a register nor in the condition flags. Also it's a perfectly valid encoding. Kudos to Peter Maydell for coming up with this gem. [0] https://lore.kernel.org/qemu-devel/YTPIdbUCmwagL5%2FD@os.inf.tu-dresden.de/T/ Link: https://lore.kernel.org/linux-arm-kernel/20210908162617.104962-1-andre.przywara@arm.com/T/ Fixes: 81a0bc39ea19 ("ARM: add UEFI stub support") Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reported-by: Adam Lackorzynski <adam@l4re.org> Suggested-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-12-17ARM: 9154/1: decompressor: do not copy source files while buildingMasahiro Yamada7-35/+16
As commit 7ae4a78daacf ("ARM: 8969/1: decompressor: simplify libfdt builds") stated, copying source files during the build time may not end up with as clean code as expected. Do similar for the other library files for further cleanups of the Makefile and .gitignore. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-12-03ARM: decompressor: disable stack protectorArd Biesheuvel2-12/+1
Enabling the stack protector in the decompressor is of dubious value, given that it uses a fixed value for the canary, cannot print any output unless CONFIG_DEBUG_LL is enabled (which relies on board specific build time settings), and is already disabled for a good chunk of the code (libfdt). So let's just disable it in the decompressor. This will make it easier in the future to manage the command line options that would need to be removed again in this context for the TLS register based stack protector. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2021-11-02Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds1-6/+42
Pull ARM updates from Russell King: - Rejig task/thread info to place thread info in task struct - Amba bus cleanups (removing unused functions) - Handle Amba device probe without IRQ domains - Parse linux,usable-memory-range in decompressor - Mark OCRAM as read-only after initialisation - Refactor page fault handling - Fix PXN handling with LPAE kernels - Warning and build fixes from Arnd * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (32 commits) ARM: 9151/1: Thumb2: avoid __builtin_thread_pointer() on Clang ARM: 9150/1: Fix PID_IN_CONTEXTIDR regression when THREAD_INFO_IN_TASK=y ARM: 9147/1: add printf format attribute to early_print() ARM: 9146/1: RiscPC needs older gcc version ARM: 9145/1: patch: fix BE32 compilation ARM: 9144/1: forbid ftrace with clang and thumb2_kernel ARM: 9143/1: add CONFIG_PHYS_OFFSET default values ARM: 9142/1: kasan: work around LPAE build warning ARM: 9140/1: allow compile-testing without machine record ARM: 9137/1: disallow CONFIG_THUMB with ARMv4 ARM: 9136/1: ARMv7-M uses BE-8, not BE-32 ARM: 9135/1: kprobes: address gcc -Wempty-body warning ARM: 9101/1: sa1100/assabet: convert LEDs to gpiod APIs ARM: 9131/1: mm: Fix PXN process with LPAE feature ARM: 9130/1: mm: Provide die_kernel_fault() helper ARM: 9126/1: mm: Kill page table base print in show_pte() ARM: 9127/1: mm: Cleanup access_error() ARM: 9129/1: mm: Kill task_struct argument for __do_page_fault() ARM: 9128/1: mm: Refactor the __do_page_fault() ARM: imx6: mark OCRAM mapping read-only ...
2021-11-02Merge branches 'devel-stable' and 'misc' into for-linusRussell King (Oracle)1-6/+42
2021-11-02Merge tag 'overflow-v5.16-rc1' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull overflow updates from Kees Cook: "The end goal of the current buffer overflow detection work[0] is to gain full compile-time and run-time coverage of all detectable buffer overflows seen via array indexing or memcpy(), memmove(), and memset(). The str*() family of functions already have full coverage. While much of the work for these changes have been on-going for many releases (i.e. 0-element and 1-element array replacements, as well as avoiding false positives and fixing discovered overflows[1]), this series contains the foundational elements of several related buffer overflow detection improvements by providing new common helpers and FORTIFY_SOURCE changes needed to gain the introspection required for compiler visibility into array sizes. Also included are a handful of already Acked instances using the helpers (or related clean-ups), with many more waiting at the ready to be taken via subsystem-specific trees[2]. The new helpers are: - struct_group() for gaining struct member range introspection - memset_after() and memset_startat() for clearing to the end of structures - DECLARE_FLEX_ARRAY() for using flex arrays in unions or alone in structs Also included is the beginning of the refactoring of FORTIFY_SOURCE to support memcpy() introspection, fix missing and regressed coverage under GCC, and to prepare to fix the currently broken Clang support. Finishing this work is part of the larger series[0], but depends on all the false positives and buffer overflow bug fixes to have landed already and those that depend on this series to land. As part of the FORTIFY_SOURCE refactoring, a set of both a compile-time and run-time tests are added for FORTIFY_SOURCE and the mem*()-family functions respectively. The compile time tests have found a legitimate (though corner-case) bug[6] already. Please note that the appearance of "panic" and "BUG" in the FORTIFY_SOURCE refactoring are the result of relocating existing code, and no new use of those code-paths are expected nor desired. Finally, there are two tree-wide conversions for 0-element arrays and flexible array unions to gain sane compiler introspection coverage that result in no known object code differences. After this series (and the changes that have now landed via netdev and usb), we are very close to finally being able to build with -Warray-bounds and -Wzero-length-bounds. However, due corner cases in GCC[3] and Clang[4], I have not included the last two patches that turn on these options, as I don't want to introduce any known warnings to the build. Hopefully these can be solved soon" Link: https://lore.kernel.org/lkml/20210818060533.3569517-1-keescook@chromium.org/ [0] Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/?qt=grep&q=FORTIFY_SOURCE [1] Link: https://lore.kernel.org/lkml/202108220107.3E26FE6C9C@keescook/ [2] Link: https://lore.kernel.org/lkml/3ab153ec-2798-da4c-f7b1-81b0ac8b0c5b@roeck-us.net/ [3] Link: https://bugs.llvm.org/show_bug.cgi?id=51682 [4] Link: https://lore.kernel.org/lkml/202109051257.29B29745C0@keescook/ [5] Link: https://lore.kernel.org/lkml/20211020200039.170424-1-keescook@chromium.org/ [6] * tag 'overflow-v5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (30 commits) fortify: strlen: Avoid shadowing previous locals compiler-gcc.h: Define __SANITIZE_ADDRESS__ under hwaddress sanitizer treewide: Replace 0-element memcpy() destinations with flexible arrays treewide: Replace open-coded flex arrays in unions stddef: Introduce DECLARE_FLEX_ARRAY() helper btrfs: Use memset_startat() to clear end of struct string.h: Introduce memset_startat() for wiping trailing members and padding xfrm: Use memset_after() to clear padding string.h: Introduce memset_after() for wiping trailing members/padding lib: Introduce CONFIG_MEMCPY_KUNIT_TEST fortify: Add compile-time FORTIFY_SOURCE tests fortify: Allow strlen() and strnlen() to pass compile-time known lengths fortify: Prepare to improve strnlen() and strlen() warnings fortify: Fix dropped strcpy() compile-time write overflow check fortify: Explicitly disable Clang support fortify: Move remaining fortify helpers into fortify-string.h lib/string: Move helper functions out of string.c compiler_types.h: Remove __compiletime_object_size() cm4000_cs: Use struct_group() to zero struct cm4000_dev region can: flexcan: Use struct_group() to zero struct flexcan_regs regions ...
2021-10-19ARM: 9134/1: remove duplicate memcpy() definitionArnd Bergmann1-0/+3
Both the decompressor code and the kasan logic try to override the memcpy() and memmove() definitions, which leading to a clash in a KASAN-enabled kernel with XZ decompression: arch/arm/boot/compressed/decompress.c:50:9: error: 'memmove' macro redefined [-Werror,-Wmacro-redefined] #define memmove memmove ^ arch/arm/include/asm/string.h:59:9: note: previous definition is here #define memmove(dst, src, len) __memmove(dst, src, len) ^ arch/arm/boot/compressed/decompress.c:51:9: error: 'memcpy' macro redefined [-Werror,-Wmacro-redefined] #define memcpy memcpy ^ arch/arm/include/asm/string.h:58:9: note: previous definition is here #define memcpy(dst, src, len) __memcpy(dst, src, len) ^ Here we want the set of functions from the decompressor, so undefine the other macros before the override. Link: https://lore.kernel.org/linux-arm-kernel/CACRpkdZYJogU_SN3H9oeVq=zJkRgRT1gDz3xp59gdqWXxw-B=w@mail.gmail.com/ Link: https://lore.kernel.org/lkml/202105091112.F5rmd4By-lkp@intel.com/ Fixes: d6d51a96c7d6 ("ARM: 9014/2: Replace string mem* functions for KASan") Fixes: a7f464f3db93 ("ARM: 7001/2: Wire up support for the XZ decompressor") Reported-by: kernel test robot <lkp@intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-10-19ARM: 9124/1: uncompress: Parse "linux,usable-memory-range" DT propertyGeert Uytterhoeven1-6/+42
Add support for parsing the "linux,usable-memory-range" DT property. This property is used to describe the usable memory reserved for the crash dump kernel, and thus makes the memory reservation explicit. If present, Linux no longer needs to mask the program counter, and rely on the "mem=" kernel parameter to obtain the start and size of usable memory. For backwards compatibility, the traditional method to derive the start of memory is still used if "linux,usable-memory-range" is absent. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-09-25lib/string: Move helper functions out of string.cKees Cook1-0/+1
The core functions of string.c are those that may be implemented by per-architecture functions, or overloaded by FORTIFY_SOURCE. As a result, it needs to be built with __NO_FORTIFY. Without this, macros will collide with function declarations. This was accidentally working due to -ffreestanding (on some architectures). Make this deterministic by explicitly setting __NO_FORTIFY and move all the helper functions into string_helpers.c so that they gain the fortification coverage they had been missing. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Andy Lavr <andy.lavr@gmail.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2021-08-10ARM: 9105/1: atags_to_fdt: don't warn about stack sizeDavid Heidelberg1-0/+2
The merge_fdt_bootargs() function by definition consumes more than 1024 bytes of stack because it has a 1024 byte command line on the stack, meaning that we always get a warning when building this file: arch/arm/boot/compressed/atags_to_fdt.c: In function 'merge_fdt_bootargs': arch/arm/boot/compressed/atags_to_fdt.c:98:1: warning: the frame size of 1032 bytes is larger than 1024 bytes [-Wframe-larger-than=] However, as this is the decompressor and we know that it has a very shallow call chain, and we do not actually risk overflowing the kernel stack at runtime here. This just shuts up the warning by disabling the warning flag for this file. Tested on Nexus 7 2012 builds. Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: David Heidelberg <david@ixit.cz> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: <stable@vger.kernel.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2021-06-07ARM: 9083/1: uncompress: atags_to_fdt: Spelling s/REturn/Return/Geert Uytterhoeven1-1/+1
Fix a capitalization typo. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-06-07ARM: 9076/1: boot: remove redundant piggy_data from clean-filesMasahiro Yamada1-1/+1
Kbuild cleans up files listed in 'targets'. 'piggy_data' is already added to 'targets' a few lines above. Adding it to 'clean-files' is redundant. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-05-08Merge tag 'kbuild-v5.13-2' of ↵Linus Torvalds1-7/+0
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull more Kbuild updates from Masahiro Yamada: - Convert sh and sparc to use generic shell scripts to generate the syscall headers - refactor .gitignore files - Update kernel/config_data.gz only when the content of the .config is really changed, which avoids the unneeded re-link of vmlinux - move "remove stale files" workarounds to scripts/remove-stale-files - suppress unused-but-set-variable warnings by default for Clang as well - fix locale setting LANG=C to LC_ALL=C - improve 'make distclean' - always keep intermediate objects from scripts/link-vmlinux.sh - move IF_ENABLED out of <linux/kconfig.h> to make it self-contained - misc cleanups * tag 'kbuild-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits) linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h> kbuild: Don't remove link-vmlinux temporary files on exit/signal kbuild: remove the unneeded comments for external module builds kbuild: make distclean remove tag files in sub-directories kbuild: make distclean work against $(objtree) instead of $(srctree) kbuild: refactor modname-multi by using suffix-search kbuild: refactor fdtoverlay rule kbuild: parameterize the .o part of suffix-search arch: use cross_compiling to check whether it is a cross build or not kbuild: remove ARCH=sh64 support from top Makefile .gitignore: prefix local generated files with a slash kbuild: replace LANG=C with LC_ALL=C Makefile: Move -Wno-unused-but-set-variable out of GCC only block kbuild: add a script to remove stale generated files kbuild: update config_data.gz only when the content of .config is changed .gitignore: ignore only top-level modules.builtin .gitignore: move tags and TAGS close to other tag files kernel/.gitgnore: remove stale timeconst.h and hz.bc usr/include: refactor .gitignore genksyms: fix stale comment ...
2021-05-01kbuild: add a script to remove stale generated filesMasahiro Yamada1-7/+0
We maintain .gitignore and Makefiles so build artifacts are properly ignored by Git, and cleaned up by 'make clean'. However, the code is always changing; generated files are often moved to another directory, or removed when they become unnecessary. Such garbage files tend to be left over in the source tree because people usually git-pull without cleaning the tree. This is not only the noise for 'git status', but also a build issue in some cases. One solution is to remove a stale file like commit 223c24a7dba9 ("kbuild: Automatically remove stale <linux/version.h> file") did. Such workaround should be removed after a while, but we forget about that if we scatter the workaround code in random places. So, this commit adds a new script to collect cleanings of stale files. As a start point, move the code in arch/arm/boot/compressed/Makefile into this script. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2021-03-09ARM: 9056/1: decompressor: fix BSS size calculation for LLVM ld.lldArd Biesheuvel1-2/+2
The LLVM ld.lld linker uses a different symbol type for __bss_start, resulting in the calculation of KBSS_SZ to be thrown off. Up until now, this has gone unnoticed as it only affects the appended DTB case, but pending changes for ARM in the way the decompressed kernel is cleaned from the caches has uncovered this problem. On a ld.lld build: $ nm vmlinux |grep bss_ c1c22034 D __bss_start c1c86e98 B __bss_stop resulting in $ readelf -s arch/arm/boot/compressed/vmlinux | grep bss_size 433: c1c86e98 0 NOTYPE GLOBAL DEFAULT ABS _kernel_bss_size which is obviously incorrect, and may cause the cache clean to access unmapped memory, or cause the size calculation to wrap, resulting in no cache clean to be performed at all. Fix this by updating the sed regex to take D type symbols into account. Link: https://lore.kernel.org/linux-arm-kernel/6c65bcef-d4e7-25fa-43cf-2c435bb61bb9@collabora.com/ Link: https://lore.kernel.org/linux-arm-kernel/20210205085220.31232-1-ardb@kernel.org/ Cc: <stable@vger.kernel.org> # v4.19+ Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Reported-by: Guillaume Tucker <guillaume.tucker@collabora.com> Reported-by: "kernelci.org bot" <bot@kernelci.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-02-23Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds3-10/+171
Pull ARM updates from Russell King: - Generalise byte swapping assembly - Update debug addresses for STI - Validate start of physical memory with DTB - Do not clear SCTLR.nTLSMD in decompressor - amba/locomo/sa1111 devices remove method return type is void - address markers for KASAN in page table dump * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 9065/1: OABI compat: fix build when EPOLL is not enabled ARM: 9055/1: mailbox: arm_mhuv2: make remove callback return void amba: Make use of bus_type functions amba: Make the remove callback return void vfio: platform: simplify device removal amba: reorder functions amba: Fix resource leak for drivers without .remove ARM: 9054/1: arch/arm/mm/mmu.c: Remove duplicate header ARM: 9053/1: arm/mm/ptdump:Add address markers for KASAN regions ARM: 9051/1: vdso: remove unneded extra-y addition ARM: 9050/1: Kconfig: Select ARCH_HAVE_NMI_SAFE_CMPXCHG where possible ARM: 9049/1: locomo: make locomo bus's remove callback return void ARM: 9048/1: sa1111: make sa1111 bus's remove callback return void ARM: 9047/1: smp: remove unused variable ARM: 9046/1: decompressor: Do not clear SCTLR.nTLSMD for ARMv7+ cores ARM: 9045/1: uncompress: Validate start of physical memory against passed DTB ARM: 9042/1: debug: no uncompress debugging while semihosting ARM: 9041/1: sti LL_UART: add STiH418 SBC UART0 support ARM: 9040/1: use DEBUG_UART_PHYS and DEBUG_UART_VIRT for sti LL_UART ARM: 9039/1: assembler: generalize byte swapping macro into rev_l
2021-02-01ARM: 9046/1: decompressor: Do not clear SCTLR.nTLSMD for ARMv7+ coresVladimir Murzin1-2/+2
It was observed that decompressor running on hardware implementing ARM v8.2 Load/Store Multiple Atomicity and Ordering Control (LSMAOC), say, as guest, would stuck just after: Uncompressing Linux... done, booting the kernel. The reason is that it clears nTLSMD bit when disabling caches: nTLSMD, bit [3] When ARMv8.2-LSMAOC is implemented: No Trap Load Multiple and Store Multiple to Device-nGRE/Device-nGnRE/Device-nGnRnE memory. 0b0 All memory accesses by A32 and T32 Load Multiple and Store Multiple at EL1 or EL0 that are marked at stage 1 as Device-nGRE/Device-nGnRE/Device-nGnRnE memory are trapped and generate a stage 1 Alignment fault. 0b1 All memory accesses by A32 and T32 Load Multiple and Store Multiple at EL1 or EL0 that are marked at stage 1 as Device-nGRE/Device-nGnRE/Device-nGnRnE memory are not trapped. This bit is permitted to be cached in a TLB. This field resets to 1. Otherwise: Reserved, RES1 So as effect we start getting traps we are not quite ready for. Looking into history it seems that mask used for SCTLR clear came from the similar code for ARMv4, where bit[3] is the enable/disable bit for the write buffer. That not applicable to ARMv7 and onwards, so retire that bit from the masks. Fixes: 7d09e85448dfa78e3e58186c934449aaf6d49b50 ("[ARM] 4393/2: ARMv7: Add uncompressing code for the new CPU Id format") Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-02-01ARM: 9045/1: uncompress: Validate start of physical memory against passed DTBGeert Uytterhoeven3-4/+168
Currently, the start address of physical memory is obtained by masking the program counter with a fixed mask of 0xf8000000. This mask value was chosen as a balance between the requirements of different platforms. However, this does require that the start address of physical memory is a multiple of 128 MiB, precluding booting Linux on platforms where this requirement is not fulfilled. Fix this limitation by validating the masked address against the memory information in the passed DTB. Only use the start address from DTB when masking would yield an out-of-range address, prefer the traditional method in all other cases. Note that this applies only to the explicitly passed DTB on modern systems, and not to a DTB appended to the kernel, or to ATAGS. The appended DTB may need to be augmented by information from ATAGS, which may need to rely on knowledge of the start address of physical memory itself. This allows to boot Linux on r7s9210/rza2mevb using the 64 MiB of SDRAM on the RZA2MEVB sub board, which is located at 0x0C000000 (CS3 space), i.e. not at a multiple of 128 MiB. Suggested-by: Nicolas Pitre <nico@fluxnic.net> Suggested-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-02-01ARM: 9039/1: assembler: generalize byte swapping macro into rev_lArd Biesheuvel1-4/+1
Take the 4 instruction byte swapping sequence from the decompressor's head.S, and turn it into a rev_l GAS macro for general use. While at it, make it use the 'rev' instruction when compiling for v6 or later. Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-01-27ARM: zImage: atags_to_fdt: Fix node names on added root nodesRob Herring1-1/+2
Commit 7536c7e03e74 ("of/fdt: Remove redundant kbasename function call") exposed a bug creating DT nodes in the ATAGS to DT fixup code. Non-existent nodes would mistaken get created with a leading '/'. The problem was fdt_path_offset() takes a full path while creating a node with fdt_add_subnode() takes just the basename. Since this we only add root child nodes, we can just skip over the '/'. Fixes: 7536c7e03e74 ("of/fdt: Remove redundant kbasename function call") Reported-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Cc: Qi Zheng <arch0.zheng@gmail.com> Cc: Russell King <linux@armlinux.org.uk> Signed-off-by: Rob Herring <robh@kernel.org> Tested-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Link: https://lore.kernel.org/r/20210126023905.1631161-1-robh@kernel.org
2020-12-23Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linuxLinus Torvalds3-36/+44
Pull ARM updates from Russell King: - Rework phys/virt translation - Add KASan support - Move DT out of linear map region - Use more PC-relative addressing in assembly - Remove FP emulation handling while in kernel mode - Link with '-z norelro' - remove old check for GCC <= 4.2 in ARM unwinder code - disable big endian if using clang's linker * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (46 commits) ARM: 9027/1: head.S: explicitly map DT even if it lives in the first physical section ARM: 9038/1: Link with '-z norelro' ARM: 9037/1: uncompress: Add OF_DT_MAGIC macro ARM: 9036/1: uncompress: Fix dbgadtb size parameter name ARM: 9035/1: uncompress: Add be32tocpu macro ARM: 9033/1: arm/smp: Drop the macro S(x,s) ARM: 9032/1: arm/mm: Convert PUD level pgtable helper macros into functions ARM: 9031/1: hyp-stub: remove unused .L__boot_cpu_mode_offset symbol ARM: 9044/1: vfp: use undef hook for VFP support detection ARM: 9034/1: __div64_32(): straighten up inline asm constraints ARM: 9030/1: entry: omit FP emulation for UND exceptions taken in kernel mode ARM: 9029/1: Make iwmmxt.S support Clang's integrated assembler ARM: 9028/1: disable KASAN in call stack capturing routines ARM: 9026/1: unwind: remove old check for GCC <= 4.2 ARM: 9025/1: Kconfig: CPU_BIG_ENDIAN depends on !LD_IS_LLD ARM: 9024/1: Drop useless cast of "u64" to "long long" ARM: 9023/1: Spelling s/mmeory/memory/ ARM: 9022/1: Change arch/arm/lib/mem*.S to use WEAK instead of .weak ARM: kvm: replace open coded VA->PA calculations with adr_l call ARM: head.S: use PC relative insn sequence to calculate PHYS_OFFSET ...
2020-12-21Merge branch 'devel-stable' into for-nextRussell King1-15/+3
2020-12-21ARM: 9037/1: uncompress: Add OF_DT_MAGIC macroGeert Uytterhoeven1-5/+7
The DTB magic marker is stored as a 32-bit big-endian value, and thus depends on the CPU's endianness. Add a macro to define this value in native endianness, to reduce #ifdef clutter and (future) duplication. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>