linux-dev/drivers/misc/lkdtm, branch master

Merge tag 'hardening-v6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

2022-10-04T00:24:22Z

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 ...

treewide: Drop function_nocfi

2022-09-26T17:13:14Z

With -fsanitize=kcfi, we no longer need function_nocfi() as the compiler won't change function references to point to a jump table. Remove all implementations and uses of the macro. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Tested-by: Kees Cook Tested-by: Nathan Chancellor Acked-by: Peter Zijlstra (Intel) Tested-by: Peter Zijlstra (Intel) Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20220908215504.3686827-14-samitolvanen@google.com

lkdtm: Emit an indirect call for CFI tests

2022-09-26T17:13:13Z

Clang can convert the indirect calls in lkdtm_CFI_FORWARD_PROTO into direct calls. Move the call into a noinline function that accepts the target address as an argument to ensure the compiler actually emits an indirect call instead. Signed-off-by: Sami Tolvanen Reviewed-by: Nick Desaulniers Tested-by: Kees Cook Tested-by: Nathan Chancellor Acked-by: Kees Cook Acked-by: Peter Zijlstra (Intel) Tested-by: Peter Zijlstra (Intel) Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20220908215504.3686827-8-samitolvanen@google.com

lkdtm: Update tests for memcpy() run-time warnings

2022-09-07T23:37:27Z

Clarify the LKDTM FORTIFY tests, and add tests for the mem*() family of functions, now that run-time checking is distinct. Cc: Arnd Bergmann Cc: Greg Kroah-Hartman Cc: Shuah Khan Cc: linux-kselftest@vger.kernel.org Signed-off-by: Kees Cook

Merge tag 'char-misc-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2022-08-04T18:05:48Z

Pull char / misc driver updates from Greg KH: "Here is the large set of char and misc and other driver subsystem changes for 6.0-rc1. Highlights include: - large set of IIO driver updates, additions, and cleanups - new habanalabs device support added (loads of register maps much like GPUs have) - soundwire driver updates - phy driver updates - slimbus driver updates - tiny virt driver fixes and updates - misc driver fixes and updates - interconnect driver updates - hwtracing driver updates - fpga driver updates - extcon driver updates - firmware driver updates - counter driver update - mhi driver fixes and updates - binder driver fixes and updates - speakup driver fixes All of these have been in linux-next for a while without any reported problems" * tag 'char-misc-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (634 commits) drivers: lkdtm: fix clang -Wformat warning char: remove VR41XX related char driver misc: Mark MICROCODE_MINOR unused spmi: trace: fix stack-out-of-bound access in SPMI tracing functions dt-bindings: iio: adc: Add compatible for MT8188 iio: light: isl29028: Fix the warning in isl29028_remove() iio: accel: sca3300: Extend the trigger buffer from 16 to 32 bytes iio: fix iio_format_avail_range() printing for none IIO_VAL_INT iio: adc: max1027: unlock on error path in max1027_read_single_value() iio: proximity: sx9324: add empty line in front of bullet list iio: magnetometer: hmc5843: Remove duplicate 'the' iio: magn: yas530: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr() macros iio: magnetometer: ak8974: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr() macros iio: light: veml6030: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr() macros iio: light: vcnl4035: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr() macros iio: light: vcnl4000: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr() macros iio: light: tsl2591: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr() iio: light: tsl2583: Use DEFINE_RUNTIME_DEV_PM_OPS and pm_ptr() iio: light: isl29028: Use DEFINE_RUNTIME_DEV_PM_OPS() and pm_ptr() iio: light: gp2ap002: Switch to DEFINE_RUNTIME_DEV_PM_OPS and pm_ptr() ...

Merge tag 'hardening-v5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

2022-08-02T21:38:59Z

Pull hardening updates from Kees Cook: - Fix Sparse warnings with randomizd kstack (GONG, Ruiqi) - Replace uintptr_t with unsigned long in usercopy (Jason A. Donenfeld) - Fix Clang -Wforward warning in LKDTM (Justin Stitt) - Fix comment to correctly refer to STRICT_DEVMEM (Lukas Bulwahn) - Introduce dm-verity binding logic to LoadPin LSM (Matthias Kaehlcke) - Clean up warnings and overflow and KASAN tests (Kees Cook) * tag 'hardening-v5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: dm: verity-loadpin: Drop use of dm_table_get_num_targets() kasan: test: Silence GCC 12 warnings drivers: lkdtm: fix clang -Wformat warning x86: mm: refer to the intended config STRICT_DEVMEM in a comment dm: verity-loadpin: Use CONFIG_SECURITY_LOADPIN_VERITY for conditional compilation LoadPin: Enable loading from trusted dm-verity devices dm: Add verity helpers for LoadPin stack: Declare {randomize_,}kstack_offset to fix Sparse warnings lib: overflow: Do not define 64-bit tests on 32-bit MAINTAINERS: Add a general "kernel hardening" section usercopy: use unsigned long instead of uintptr_t

drivers: lkdtm: fix clang -Wformat warning

2022-07-28T14:20:36Z

When building with Clang we encounter the following warning (ARCH=hexagon + CONFIG_FRAME_WARN=0): | ../drivers/misc/lkdtm/bugs.c:107:3: error: format specifies type | 'unsigned long' but the argument has type 'int' [-Werror,-Wformat] | REC_STACK_SIZE, recur_count); | ^~~~~~~~~~~~~~ Cast REC_STACK_SIZE to `unsigned long` to match format specifier `%lu` as well as maintain symmetry with `#define REC_STACK_SIZE (_AC(CONFIG_FRAME_WARN, UL) / 2)`. Link: https://github.com/ClangBuiltLinux/linux/issues/378 Fixes: 24cccab42c419 ("lkdtm/bugs: Adjust recursion test to avoid elision") Reported-by: Nathan Chancellor Suggested-by: Nathan Chancellor Suggested-by: Nick Desaulniers Tested-by: Nathan Chancellor Reviewed-by: Nathan Chancellor Acked-by: Kees Cook Signed-off-by: Justin Stitt Link: https://lore.kernel.org/r/20220721215706.4153027-1-justinstitt@google.com Signed-off-by: Greg Kroah-Hartman

drivers: lkdtm: fix clang -Wformat warning

2022-07-27T19:16:17Z

When building with Clang we encounter the following warning (ARCH=hexagon + CONFIG_FRAME_WARN=0): | ../drivers/misc/lkdtm/bugs.c:107:3: error: format specifies type | 'unsigned long' but the argument has type 'int' [-Werror,-Wformat] | REC_STACK_SIZE, recur_count); | ^~~~~~~~~~~~~~ Cast REC_STACK_SIZE to `unsigned long` to match format specifier `%lu` as well as maintain symmetry with `#define REC_STACK_SIZE (_AC(CONFIG_FRAME_WARN, UL) / 2)`. Link: https://github.com/ClangBuiltLinux/linux/issues/378 Reported-by: Nathan Chancellor Suggested-by: Nathan Chancellor Suggested-by: Nick Desaulniers Signed-off-by: Justin Stitt Reviewed-by: Nathan Chancellor Tested-by: Nathan Chancellor Acked-by: Kees Cook Fixes: 24cccab42c419 ("lkdtm/bugs: Adjust recursion test to avoid elision") Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20220721215706.4153027-1-justinstitt@google.com

lkdtm: Disable return thunks in rodata.c

2022-07-20T17:24:53Z

The following warning was seen: WARNING: CPU: 0 PID: 0 at arch/x86/kernel/alternative.c:557 apply_returns (arch/x86/kernel/alternative.c:557 (discriminator 1)) Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.19.0-rc4-00008-gee88d363d156 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-4 04/01/2014 RIP: 0010:apply_returns (arch/x86/kernel/alternative.c:557 (discriminator 1)) Code: ff ff 74 cb 48 83 c5 04 49 39 ee 0f 87 81 fe ff ff e9 22 ff ff ff 0f 0b 48 83 c5 04 49 39 ee 0f 87 6d fe ff ff e9 0e ff ff ff <0f> 0b 48 83 c5 04 49 39 ee 0f 87 59 fe ff ff e9 fa fe ff ff 48 89 The warning happened when apply_returns() failed to convert "JMP __x86_return_thunk" to RET. It was instead a JMP to nowhere, due to the thunk relocation not getting resolved. That rodata.o code is objcopy'd to .rodata, and later memcpy'd, so relocations don't work (and are apparently silently ignored). LKDTM is only used for testing, so the naked RET should be fine. So just disable return thunks for that file. While at it, disable objtool and KCSAN for the file. Fixes: 0b53c374b9ef ("x86/retpoline: Use -mfunction-return") Reported-by: kernel test robot Debugged-by: Peter Zijlstra Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/lkml/Ys58BxHxoDZ7rfpr@xsang-OptiPlex-9020/

lkdtm: cfi: use NULL for a null pointer rather than zero

2022-06-27T14:16:07Z

There is a pointer being initialized with a zero, use NULL instead. Cleans up sparse warning: drivers/misc/lkdtm/cfi.c:100:27: warning: Using plain integer as NULL pointer Acked-by: Kees Cook Signed-off-by: Colin Ian King Link: https://lore.kernel.org/r/20220612202708.2754270-1-colin.i.king@gmail.com Signed-off-by: Greg Kroah-Hartman