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2023-12-20UBSAN: use the kernel panic message markersBorislav Petkov (AMD)1-4/+3
Use the same splat markers as panic does for easier matching by external tools scanning kernel dmesg for splats. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Borislav Petkov (AMD) <[email protected]> Cc: Andrey Ryabinin <[email protected]> Signed-off-by: Andrew Morton <[email protected]>
2023-05-30ubsan: add prototypes for internal functionsArnd Bergmann1-3/+0
Most of the functions in ubsan that are only called from generated code don't have a prototype, which W=1 builds warn about: lib/ubsan.c:226:6: error: no previous prototype for '__ubsan_handle_divrem_overflow' [-Werror=missing-prototypes] lib/ubsan.c:307:6: error: no previous prototype for '__ubsan_handle_type_mismatch' [-Werror=missing-prototypes] lib/ubsan.c:321:6: error: no previous prototype for '__ubsan_handle_type_mismatch_v1' [-Werror=missing-prototypes] lib/ubsan.c:335:6: error: no previous prototype for '__ubsan_handle_out_of_bounds' [-Werror=missing-prototypes] lib/ubsan.c:352:6: error: no previous prototype for '__ubsan_handle_shift_out_of_bounds' [-Werror=missing-prototypes] lib/ubsan.c:394:6: error: no previous prototype for '__ubsan_handle_builtin_unreachable' [-Werror=missing-prototypes] lib/ubsan.c:404:6: error: no previous prototype for '__ubsan_handle_load_invalid_value' [-Werror=missing-prototypes] Add prototypes for all of these to lib/ubsan.h, and remove the one that was already present in ubsan.c. Signed-off-by: Arnd Bergmann <[email protected]> Reviewed-by: Fangrui Song <[email protected]> Signed-off-by: Kees Cook <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2023-02-21Merge tag 'hardening-v6.3-rc1' of ↵Linus Torvalds1-0/+68
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: "Beyond some specific LoadPin, UBSAN, and fortify features, there are other fixes scattered around in various subsystems where maintainers were okay with me carrying them in my tree or were non-responsive but the patches were reviewed by others: - Replace 0-length and 1-element arrays with flexible arrays in various subsystems (Paulo Miguel Almeida, Stephen Rothwell, Kees Cook) - randstruct: Disable Clang 15 support (Eric Biggers) - GCC plugins: Drop -std=gnu++11 flag (Sam James) - strpbrk(): Refactor to use strchr() (Andy Shevchenko) - LoadPin LSM: Allow root filesystem switching when non-enforcing - fortify: Use dynamic object size hints when available - ext4: Fix CFI function prototype mismatch - Nouveau: Fix DP buffer size arguments - hisilicon: Wipe entire crypto DMA pool on error - coda: Fully allocate sig_inputArgs - UBSAN: Improve arm64 trap code reporting - copy_struct_from_user(): Add minimum bounds check on kernel buffer size" * tag 'hardening-v6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: randstruct: disable Clang 15 support uaccess: Add minimum bounds check on kernel buffer size arm64: Support Clang UBSAN trap codes for better reporting coda: Avoid partial allocation of sig_inputArgs gcc-plugins: drop -std=gnu++11 to fix GCC 13 build lib/string: Use strchr() in strpbrk() crypto: hisilicon: Wipe entire pool on error net/i40e: Replace 0-length array with flexible array io_uring: Replace 0-length array with flexible array ext4: Fix function prototype mismatch for ext4_feat_ktype i915/gvt: Replace one-element array with flexible-array member drm/nouveau/disp: Fix nvif_outp_acquire_dp() argument size LoadPin: Allow filesystem switch when not enforcing LoadPin: Move pin reporting cleanly out of locking LoadPin: Refactor sysctl initialization LoadPin: Refactor read-only check into a helper ARM: ixp4xx: Replace 0-length arrays with flexible arrays fortify: Use __builtin_dynamic_object_size() when available rxrpc: replace zero-lenth array with DECLARE_FLEX_ARRAY() helper
2023-02-08arm64: Support Clang UBSAN trap codes for better reportingKees Cook1-0/+68
When building with CONFIG_UBSAN_TRAP=y on arm64, Clang encodes the UBSAN check (handler) type in the esr. Extract this and actually report these traps as coming from the specific UBSAN check that tripped. Before: Internal error: BRK handler: 00000000f20003e8 [#1] PREEMPT SMP After: Internal error: UBSAN: shift out of bounds: 00000000f2005514 [#1] PREEMPT SMP Acked-by: Mark Rutland <[email protected]> Reviewed-by: Ard Biesheuvel <[email protected]> Acked-by: Mukesh Ojha <[email protected]> Reviewed-by: Fangrui Song <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Will Deacon <[email protected]> Cc: John Stultz <[email protected]> Cc: Yongqin Liu <[email protected]> Cc: Sami Tolvanen <[email protected]> Cc: Yury Norov <[email protected]> Cc: Andrey Konovalov <[email protected]> Cc: Marco Elver <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: Kees Cook <[email protected]>
2023-01-13ubsan: Fix objtool UACCESS warnsPeter Zijlstra1-1/+4
clang-14 allyesconfig gives: vmlinux.o: warning: objtool: emulator_cmpxchg_emulated+0x705: call to __ubsan_handle_load_invalid_value() with UACCESS enabled vmlinux.o: warning: objtool: paging64_update_accessed_dirty_bits+0x39e: call to __ubsan_handle_load_invalid_value() with UACCESS enabled vmlinux.o: warning: objtool: paging32_update_accessed_dirty_bits+0x390: call to __ubsan_handle_load_invalid_value() with UACCESS enabled vmlinux.o: warning: objtool: ept_update_accessed_dirty_bits+0x43f: call to __ubsan_handle_load_invalid_value() with UACCESS enabled Add the required eflags save/restore and whitelist the thing. Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Tested-by: Tony Lindgren <[email protected]> Tested-by: Ulf Hansson <[email protected]> Acked-by: Rafael J. Wysocki <[email protected]> Acked-by: Frederic Weisbecker <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2022-12-02panic: Consolidate open-coded panic_on_warn checksKees Cook1-2/+1
Several run-time checkers (KASAN, UBSAN, KFENCE, KCSAN, sched) roll their own warnings, and each check "panic_on_warn". Consolidate this into a single function so that future instrumentation can be added in a single location. Cc: Marco Elver <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Juri Lelli <[email protected]> Cc: Vincent Guittot <[email protected]> Cc: Dietmar Eggemann <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Ben Segall <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Daniel Bristot de Oliveira <[email protected]> Cc: Valentin Schneider <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Konovalov <[email protected]> Cc: Vincenzo Frascino <[email protected]> Cc: Andrew Morton <[email protected]> Cc: David Gow <[email protected]> Cc: tangmeng <[email protected]> Cc: Jann Horn <[email protected]> Cc: Shuah Khan <[email protected]> Cc: Petr Mladek <[email protected]> Cc: "Paul E. McKenney" <[email protected]> Cc: Sebastian Andrzej Siewior <[email protected]> Cc: "Guilherme G. Piccoli" <[email protected]> Cc: Tiezhu Yang <[email protected]> Cc: [email protected] Cc: [email protected] Reviewed-by: Luis Chamberlain <[email protected]> Signed-off-by: Kees Cook <[email protected]> Reviewed-by: Marco Elver <[email protected]> Reviewed-by: Andrey Konovalov <[email protected]> Link: https://lore.kernel.org/r/[email protected]
2022-03-23ubsan: no need to unset panic_on_warn in ubsan_epilogue()Tiezhu Yang1-9/+1
panic_on_warn is unset inside panic(), so no need to unset it before calling panic() in ubsan_epilogue(). Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Tiezhu Yang <[email protected]> Reviewed-by: Marco Elver <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Baoquan He <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Xuefeng Li <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-08-13kunit: ubsan integrationUriel Guajardo1-0/+3
Integrates UBSAN into the KUnit testing framework. It fails KUnit tests whenever it reports undefined behavior. When CONFIG_KUNIT=n, nothing is printed or even formatted, so this has no behavioral impact outside of tests. kunit_fail_current_test() effectively does a pr_err() as well, so there's some slight duplication, but it also ensures an error is recorded in the debugfs entry for the running KUnit test. Print a shorter version of the message to make it less spammy. Co-developed-by: Daniel Latypov <[email protected]> Signed-off-by: Daniel Latypov <[email protected]> Signed-off-by: Uriel Guajardo <[email protected]> Reviewed-by: Alan Maguire <[email protected]> Signed-off-by: Shuah Khan <[email protected]>
2021-02-26ubsan: remove overflow checksAndrey Ryabinin1-68/+0
Since GCC 8.0 -fsanitize=signed-integer-overflow doesn't work with -fwrapv. -fwrapv makes signed overflows defines and GCC essentially disables ubsan checks. On GCC < 8.0 -fwrapv doesn't have influence on -fsanitize=signed-integer-overflow setting, so it kinda works but generates false-positves and violates uaccess rules: lib/iov_iter.o: warning: objtool: iovec_from_user()+0x22d: call to __ubsan_handle_add_overflow() with UACCESS enabled Disable signed overflow checks to avoid these problems. Remove unsigned overflow checks as well. Unsigned overflow appeared as side effect of commit cdf8a76fda4a ("ubsan: move cc-option tests into Kconfig"), but it never worked (kernel doesn't boot). And unsigned overflows are allowed by C standard, so it just pointless. Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Andrey Ryabinin <[email protected]> Acked-by: Peter Zijlstra (Intel) <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Stephen Rothwell <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Kees Cook <[email protected]> Cc: Alexander Viro <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2021-02-05ubsan: implement __ubsan_handle_alignment_assumptionNathan Chancellor1-0/+31
When building ARCH=mips 32r2el_defconfig with CONFIG_UBSAN_ALIGNMENT: ld.lld: error: undefined symbol: __ubsan_handle_alignment_assumption referenced by slab.h:557 (include/linux/slab.h:557) main.o:(do_initcalls) in archive init/built-in.a referenced by slab.h:448 (include/linux/slab.h:448) do_mounts_rd.o:(rd_load_image) in archive init/built-in.a referenced by slab.h:448 (include/linux/slab.h:448) do_mounts_rd.o:(identify_ramdisk_image) in archive init/built-in.a referenced 1579 more times Implement this for the kernel based on LLVM's handleAlignmentAssumptionImpl because the kernel is not linked against the compiler runtime. Link: https://github.com/ClangBuiltLinux/linux/issues/1245 Link: https://github.com/llvm/llvm-project/blob/llvmorg-11.0.1/compiler-rt/lib/ubsan/ubsan_handlers.cpp#L151-L190 Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Nathan Chancellor <[email protected]> Acked-by: Kees Cook <[email protected]> Reviewed-by: Nick Desaulniers <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2020-12-15lib/ubsan.c: mark type_check_kinds with static keywordZou Wei1-1/+1
Fix the following sparse warning: lib/ubsan.c:20:12: warning: symbol 'type_check_kinds' was not declared. Should it be static? [[email protected]: make it `static const char * const' while we're in there] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Zou Wei <[email protected]> Reviewed-by: Andrew Morton <[email protected]> Reviewed-by: Kees Cook <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2020-06-04lib/ubsan.c: fix gcc-10 warningsArnd Bergmann1-16/+17
The latest compiler expects slightly different function prototypes for the ubsan helpers: lib/ubsan.c:192:6: error: conflicting types for built-in function '__ubsan_handle_add_overflow'; expected 'void(void *, void *, void *)' [-Werror=builtin-declaration-mismatch] 192 | void __ubsan_handle_add_overflow(struct overflow_data *data, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ lib/ubsan.c:200:6: error: conflicting types for built-in function '__ubsan_handle_sub_overflow'; expected 'void(void *, void *, void *)' [-Werror=builtin-declaration-mismatch] 200 | void __ubsan_handle_sub_overflow(struct overflow_data *data, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ lib/ubsan.c:207:6: error: conflicting types for built-in function '__ubsan_handle_mul_overflow'; expected 'void(void *, void *, void *)' [-Werror=builtin-declaration-mismatch] 207 | void __ubsan_handle_mul_overflow(struct overflow_data *data, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ lib/ubsan.c:214:6: error: conflicting types for built-in function '__ubsan_handle_negate_overflow'; expected 'void(void *, void *)' [-Werror=builtin-declaration-mismatch] 214 | void __ubsan_handle_negate_overflow(struct overflow_data *data, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ lib/ubsan.c:234:6: error: conflicting types for built-in function '__ubsan_handle_divrem_overflow'; expected 'void(void *, void *, void *)' [-Werror=builtin-declaration-mismatch] 234 | void __ubsan_handle_divrem_overflow(struct overflow_data *data, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Change the Linux implementation to match these, using a local typed pointer. Signed-off-by: Arnd Bergmann <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Reviewed-by: Kees Cook <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Herbert Xu <[email protected]> Cc: Julien Grall <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2020-04-07ubsan: include bug type in report headerKees Cook1-21/+15
When syzbot tries to figure out how to deduplicate bug reports, it prefers seeing a hint about a specific bug type (we can do better than just "UBSAN"). This lifts the handler reason into the UBSAN report line that includes the file path that tripped a check. Unfortunately, UBSAN does not provide function names. Suggested-by: Dmitry Vyukov <[email protected]> Signed-off-by: Kees Cook <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Konovalov <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Dan Carpenter <[email protected]> Cc: Elena Petrova <[email protected]> Cc: "Gustavo A. R. Silva" <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Link: https://lore.kernel.org/lkml/CACT4Y+bsLJ-wFx_TaXqax3JByUOWB3uk787LsyMVcfW6JzzGvg@mail.gmail.com Signed-off-by: Linus Torvalds <[email protected]>
2020-04-07ubsan: check panic_on_warnKees Cook1-0/+11
Syzkaller expects kernel warnings to panic when the panic_on_warn sysctl is set. More work is needed here to have UBSan reuse the WARN infrastructure, but for now, just check the flag manually. Signed-off-by: Kees Cook <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Cc: Alexander Potapenko <[email protected]> Cc: Andrey Konovalov <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Arnd Bergmann <[email protected]> Cc: Dan Carpenter <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Elena Petrova <[email protected]> Cc: "Gustavo A. R. Silva" <[email protected]> Link: https://lore.kernel.org/lkml/CACT4Y+bsLJ-wFx_TaXqax3JByUOWB3uk787LsyMVcfW6JzzGvg@mail.gmail.com Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
2019-12-04lib/ubsan: don't serialize UBSAN reportJulien Grall1-41/+23
At the moment, UBSAN report will be serialized using a spin_lock(). On RT-systems, spinlocks are turned to rt_spin_lock and may sleep. This will result to the following splat if the undefined behavior is in a context that can sleep: BUG: sleeping function called from invalid context at /src/linux/kernel/locking/rtmutex.c:968 in_atomic(): 1, irqs_disabled(): 128, pid: 3447, name: make 1 lock held by make/3447: #0: 000000009a966332 (&mm->mmap_sem){++++}, at: do_page_fault+0x140/0x4f8 irq event stamp: 6284 hardirqs last enabled at (6283): [<ffff000011326520>] _raw_spin_unlock_irqrestore+0x90/0xa0 hardirqs last disabled at (6284): [<ffff0000113262b0>] _raw_spin_lock_irqsave+0x30/0x78 softirqs last enabled at (2430): [<ffff000010088ef8>] fpsimd_restore_current_state+0x60/0xe8 softirqs last disabled at (2427): [<ffff000010088ec0>] fpsimd_restore_current_state+0x28/0xe8 Preemption disabled at: [<ffff000011324a4c>] rt_mutex_futex_unlock+0x4c/0xb0 CPU: 3 PID: 3447 Comm: make Tainted: G W 5.2.14-rt7-01890-ge6e057589653 #911 Call trace: dump_backtrace+0x0/0x148 show_stack+0x14/0x20 dump_stack+0xbc/0x104 ___might_sleep+0x154/0x210 rt_spin_lock+0x68/0xa0 ubsan_prologue+0x30/0x68 handle_overflow+0x64/0xe0 __ubsan_handle_add_overflow+0x10/0x18 __lock_acquire+0x1c28/0x2a28 lock_acquire+0xf0/0x370 _raw_spin_lock_irqsave+0x58/0x78 rt_mutex_futex_unlock+0x4c/0xb0 rt_spin_unlock+0x28/0x70 get_page_from_freelist+0x428/0x2b60 __alloc_pages_nodemask+0x174/0x1708 alloc_pages_vma+0x1ac/0x238 __handle_mm_fault+0x4ac/0x10b0 handle_mm_fault+0x1d8/0x3b0 do_page_fault+0x1c8/0x4f8 do_translation_fault+0xb8/0xe0 do_mem_abort+0x3c/0x98 el0_da+0x20/0x24 The spin_lock() will protect against multiple CPUs to output a report together, I guess to prevent them from being interleaved. However, they can still interleave with other messages (and even splat from __might_sleep). So the lock usefulness seems pretty limited. Rather than trying to accomodate RT-system by switching to a raw_spin_lock(), the lock is now completely dropped. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Julien Grall <[email protected]> Reported-by: Andre Przywara <[email protected]> Acked-by: Andrey Ryabinin <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Sebastian Andrzej Siewior <[email protected]> Cc: Steven Rostedt <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-11-26Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds1-1/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm updates from Ingo Molnar: "The main changes in this cycle were: - Cross-arch changes to move the linker sections for NOTES and EXCEPTION_TABLE into the RO_DATA area, where they belong on most architectures. (Kees Cook) - Switch the x86 linker fill byte from x90 (NOP) to 0xcc (INT3), to trap jumps into the middle of those padding areas instead of sliding execution. (Kees Cook) - A thorough cleanup of symbol definitions within x86 assembler code. The rather randomly named macros got streamlined around a (hopefully) straightforward naming scheme: SYM_START(name, linkage, align...) SYM_END(name, sym_type) SYM_FUNC_START(name) SYM_FUNC_END(name) SYM_CODE_START(name) SYM_CODE_END(name) SYM_DATA_START(name) SYM_DATA_END(name) etc - with about three times of these basic primitives with some label, local symbol or attribute variant, expressed via postfixes. No change in functionality intended. (Jiri Slaby) - Misc other changes, cleanups and smaller fixes" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits) x86/entry/64: Remove pointless jump in paranoid_exit x86/entry/32: Remove unused resume_userspace label x86/build/vdso: Remove meaningless CFLAGS_REMOVE_*.o m68k: Convert missed RODATA to RO_DATA x86/vmlinux: Use INT3 instead of NOP for linker fill bytes x86/mm: Report actual image regions in /proc/iomem x86/mm: Report which part of kernel image is freed x86/mm: Remove redundant address-of operators on addresses xtensa: Move EXCEPTION_TABLE to RO_DATA segment powerpc: Move EXCEPTION_TABLE to RO_DATA segment parisc: Move EXCEPTION_TABLE to RO_DATA segment microblaze: Move EXCEPTION_TABLE to RO_DATA segment ia64: Move EXCEPTION_TABLE to RO_DATA segment h8300: Move EXCEPTION_TABLE to RO_DATA segment c6x: Move EXCEPTION_TABLE to RO_DATA segment arm64: Move EXCEPTION_TABLE to RO_DATA segment alpha: Move EXCEPTION_TABLE to RO_DATA segment x86/vmlinux: Move EXCEPTION_TABLE to RO_DATA segment x86/vmlinux: Actually use _etext for the end of the text segment vmlinux.lds.h: Allow EXCEPTION_TABLE to live in RO_DATA ...
2019-11-17int128: move __uint128_t compiler test to KconfigArd Biesheuvel1-1/+1
In order to use 128-bit integer arithmetic in C code, the architecture needs to have declared support for it by setting ARCH_SUPPORTS_INT128, and it requires a version of the toolchain that supports this at build time. This is why all existing tests for ARCH_SUPPORTS_INT128 also test whether __SIZEOF_INT128__ is defined, since this is only the case for compilers that can support 128-bit integers. Let's fold this additional test into the Kconfig declaration of ARCH_SUPPORTS_INT128 so that we can also use the symbol in Makefiles, e.g., to decide whether a certain object needs to be included in the first place. Cc: Masahiro Yamada <[email protected]> Signed-off-by: Ard Biesheuvel <[email protected]> Signed-off-by: Herbert Xu <[email protected]>
2019-10-28ubsan, x86: Annotate and allow __ubsan_handle_shift_out_of_bounds() in ↵Peter Zijlstra1-1/+4
uaccess regions The new check_zeroed_user() function uses variable shifts inside of a user_access_begin()/user_access_end() section and that results in GCC emitting __ubsan_handle_shift_out_of_bounds() calls, even though through value range analysis it would be able to see that the UB in question is impossible. Annotate and whitelist this UBSAN function; continued use of user_access_begin()/user_access_end() will undoubtedly result in further uses of function. Reported-by: Randy Dunlap <[email protected]> Tested-by: Randy Dunlap <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Acked-by: Randy Dunlap <[email protected]> Acked-by: Christian Brauner <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephen Rothwell <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Fixes: f5a1a536fa14 ("lib: introduce copy_struct_from_user() helper") Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner1-5/+1
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Enrico Weigelt <[email protected]> Reviewed-by: Kate Stewart <[email protected]> Reviewed-by: Allison Randal <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2019-05-06Merge branch 'core-objtool-for-linus' of ↵Linus Torvalds1-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull objtool updates from Ingo Molnar: "This is a series from Peter Zijlstra that adds x86 build-time uaccess validation of SMAP to objtool, which will detect and warn about the following uaccess API usage bugs and weirdnesses: - call to %s() with UACCESS enabled - return with UACCESS enabled - return with UACCESS disabled from a UACCESS-safe function - recursive UACCESS enable - redundant UACCESS disable - UACCESS-safe disables UACCESS As it turns out not leaking uaccess permissions outside the intended uaccess functionality is hard when the interfaces are complex and when such bugs are mostly dormant. As a bonus we now also check the DF flag. We had at least one high-profile bug in that area in the early days of Linux, and the checking is fairly simple. The checks performed and warnings emitted are: - call to %s() with DF set - return with DF set - return with modified stack frame - recursive STD - redundant CLD It's all x86-only for now, but later on this can also be used for PAN on ARM and objtool is fairly cross-platform in principle. While all warnings emitted by this new checking facility that got reported to us were fixed, there might be GCC version dependent warnings that were not reported yet - which we'll address, should they trigger. The warnings are non-fatal build warnings" * 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits) mm/uaccess: Use 'unsigned long' to placate UBSAN warnings on older GCC versions x86/uaccess: Dont leak the AC flag into __put_user() argument evaluation sched/x86_64: Don't save flags on context switch objtool: Add Direction Flag validation objtool: Add UACCESS validation objtool: Fix sibling call detection objtool: Rewrite alt->skip_orig objtool: Add --backtrace support objtool: Rewrite add_ignores() objtool: Handle function aliases objtool: Set insn->func for alternatives x86/uaccess, kcov: Disable stack protector x86/uaccess, ftrace: Fix ftrace_likely_update() vs. SMAP x86/uaccess, ubsan: Fix UBSAN vs. SMAP x86/uaccess, kasan: Fix KASAN vs SMAP x86/smap: Ditch __stringify() x86/uaccess: Introduce user_access_{save,restore}() x86/uaccess, signal: Fix AC=1 bloat x86/uaccess: Always inline user_access_begin() x86/uaccess, xen: Suppress SMAP warnings ...
2019-05-06ubsan: Remove vla bound checks.Andrey Ryabinin1-18/+0
The kernel the kernel is built with -Wvla for some time, so is not supposed to have any variable length arrays. Remove vla bounds checking from ubsan since it's useless now. Signed-off-by: Andrey Ryabinin <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-05-06ubsan: Fix nasty -Wbuiltin-declaration-mismatch GCC-9 warningsAndrey Ryabinin1-26/+23
Building lib/ubsan.c with gcc-9 results in a ton of nasty warnings like this one: lib/ubsan.c warning: conflicting types for built-in function ‘__ubsan_handle_negate_overflow’; expected ‘void(void *, void *)’ [-Wbuiltin-declaration-mismatch] The kernel's declarations of __ubsan_handle_*() often uses 'unsigned long' types in parameters while GCC these parameters as 'void *' types, hence the mismatch. Fix this by using 'void *' to match GCC's declarations. Reported-by: Linus Torvalds <[email protected]> Signed-off-by: Andrey Ryabinin <[email protected]> Fixes: c6d308534aef ("UBSAN: run-time undefined behavior sanity checker") Cc: <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2019-04-03x86/uaccess, ubsan: Fix UBSAN vs. SMAPPeter Zijlstra1-0/+4
UBSAN can insert extra code in random locations; including AC=1 sections. Typically this code is not safe and needs wrapping. So far, only __ubsan_handle_type_mismatch* have been observed in AC=1 sections and therefore only those are annotated. Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Signed-off-by: Ingo Molnar <[email protected]>
2018-11-18lib/ubsan.c: don't mark __ubsan_handle_builtin_unreachable as noreturnArnd Bergmann1-2/+1
gcc-8 complains about the prototype for this function: lib/ubsan.c:432:1: error: ignoring attribute 'noreturn' in declaration of a built-in function '__ubsan_handle_builtin_unreachable' because it conflicts with attribute 'const' [-Werror=attributes] This is actually a GCC's bug. In GCC internals __ubsan_handle_builtin_unreachable() declared with both 'noreturn' and 'const' attributes instead of only 'noreturn': https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84210 Workaround this by removing the noreturn attribute. [aryabinin: add information about GCC bug in changelog] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnd Bergmann <[email protected]> Signed-off-by: Andrey Ryabinin <[email protected]> Acked-by: Olof Johansson <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-02-06lib/ubsan: remove returns-nonnull-attribute checksAndrey Ryabinin1-24/+0
Similarly to type mismatch checks, new GCC 8.x and Clang also changed for ABI for returns_nonnull checks. While we can update our code to conform the new ABI it's more reasonable to just remove it. Because it's just dead code, we don't have any single user of returns_nonnull attribute in the whole kernel. And AFAIU the advantage that this attribute could bring would be mitigated by -fno-delete-null-pointer-checks cflag that we use to build the kernel. So it's unlikely we will have a lot of returns_nonnull attribute in future. So let's just remove the code, it has no use. [[email protected]: fix warning] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Andrey Ryabinin <[email protected]> Cc: Sodagudi Prasad <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-02-06lib/ubsan: add type mismatch handler for new GCC/ClangAndrey Ryabinin1-10/+38
UBSAN=y fails to build with new GCC/clang: arch/x86/kernel/head64.o: In function `sanitize_boot_params': arch/x86/include/asm/bootparam_utils.h:37: undefined reference to `__ubsan_handle_type_mismatch_v1' because Clang and GCC 8 slightly changed ABI for 'type mismatch' errors. Compiler now uses new __ubsan_handle_type_mismatch_v1() function with slightly modified 'struct type_mismatch_data'. Let's add new 'struct type_mismatch_data_common' which is independent from compiler's layout of 'struct type_mismatch_data'. And make __ubsan_handle_type_mismatch[_v1]() functions transform compiler-dependent type mismatch data to our internal representation. This way, we can support both old and new compilers with minimal amount of change. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Andrey Ryabinin <[email protected]> Reported-by: Sodagudi Prasad <[email protected]> Cc: <[email protected]> [4.5+] Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2018-02-06lib/ubsan.c: s/missaligned/misaligned/Andrew Morton1-2/+2
A vist from the spelling fairy. Cc: David Laight <[email protected]> Cc: Andrey Ryabinin <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2016-08-02UBSAN: fix typo in format stringNicolas Iooss1-1/+1
handle_object_size_mismatch() used %pk to format a kernel pointer with pr_err(). This seemed to be a misspelling for %pK, but using this to format a kernel pointer does not make much sence here. Therefore use %p instead, like in handle_missaligned_access(). Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Nicolas Iooss <[email protected]> Acked-by: Andrey Ryabinin <[email protected]> Cc: Joe Perches <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2016-01-20UBSAN: run-time undefined behavior sanity checkerAndrey Ryabinin1-0/+456
UBSAN uses compile-time instrumentation to catch undefined behavior (UB). Compiler inserts code that perform certain kinds of checks before operations that could cause UB. If check fails (i.e. UB detected) __ubsan_handle_* function called to print error message. So the most of the work is done by compiler. This patch just implements ubsan handlers printing errors. GCC has this capability since 4.9.x [1] (see -fsanitize=undefined option and its suboptions). However GCC 5.x has more checkers implemented [2]. Article [3] has a bit more details about UBSAN in the GCC. [1] - https://gcc.gnu.org/onlinedocs/gcc-4.9.0/gcc/Debugging-Options.html [2] - https://gcc.gnu.org/onlinedocs/gcc/Debugging-Options.html [3] - http://developerblog.redhat.com/2014/10/16/gcc-undefined-behavior-sanitizer-ubsan/ Issues which UBSAN has found thus far are: Found bugs: * out-of-bounds access - 97840cb67ff5 ("netfilter: nfnetlink: fix insufficient validation in nfnetlink_bind") undefined shifts: * d48458d4a768 ("jbd2: use a better hash function for the revoke table") * 10632008b9e1 ("clockevents: Prevent shift out of bounds") * 'x << -1' shift in ext4 - http://lkml.kernel.org/r/<[email protected]> * undefined rol32(0) - http://lkml.kernel.org/r/<[email protected]> * undefined dirty_ratelimit calculation - http://lkml.kernel.org/r/<[email protected]> * undefined roundown_pow_of_two(0) - http://lkml.kernel.org/r/<[email protected]> * [WONTFIX] undefined shift in __bpf_prog_run - http://lkml.kernel.org/r/<CACT4Y+ZxoR3UjLgcNdUm4fECLMx2VdtfrENMtRRCdgHB2n0bJA@mail.gmail.com> WONTFIX here because it should be fixed in bpf program, not in kernel. signed overflows: * 32a8df4e0b33f ("sched: Fix odd values in effective_load() calculations") * mul overflow in ntp - http://lkml.kernel.org/r/<[email protected]> * incorrect conversion into rtc_time in rtc_time64_to_tm() - http://lkml.kernel.org/r/<[email protected]> * unvalidated timespec in io_getevents() - http://lkml.kernel.org/r/<CACT4Y+bBxVYLQ6LtOKrKtnLthqLHcw-BMp3aqP3mjdAvr9FULQ@mail.gmail.com> * [NOTABUG] signed overflow in ktime_add_safe() - http://lkml.kernel.org/r/<CACT4Y+aJ4muRnWxsUe1CMnA6P8nooO33kwG-c8YZg=0Xc8rJqw@mail.gmail.com> [[email protected]: fix unused local warning] [[email protected]: fix __int128 build woes] Signed-off-by: Andrey Ryabinin <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Sasha Levin <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Rasmus Villemoes <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Michal Marek <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: Yury Gribov <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Konstantin Khlebnikov <[email protected]> Cc: Kostya Serebryany <[email protected]> Cc: Johannes Berg <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
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