Messages in this thread Patch in this message | | | From | Thomas Gleixner <> | Subject | [GIT pull] objtool/urgent for v5.19-rc1 | Date | Sun, 5 Jun 2022 11:30:50 +0200 (CEST) |
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Linus,
please pull the latest objtool/urgent branch from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git objtool-urgent-2022-06-05
up to: 2028a255f4df: x86/extable: Annotate ex_handler_msr_mce() as a dead end
A set of objtool fixes:
- Handle __ubsan_handle_builtin_unreachable() correctly and treat it as noreturn.
- Allow architectures to select uaccess validation
- Use the non-instrumented bit test for test_cpu_has() to prevent escape from non-instrumentable regions.
- Use arch_ prefixed atomics for JUMP_LABEL=n builds to prevent escape from non-instrumentable regions.
- Mark a few tiny inline as __always_inline to prevent GCC from bringing them out of line and instrumenting them.
- Mark the empty stub context_tracking_enabled() as always inline as GCC brings them out of line and instruments the empty shell.
- Annotate ex_handler_msr_mce() as dead end
Thanks,
tglx
------------------> Borislav Petkov (1): x86/extable: Annotate ex_handler_msr_mce() as a dead end
Josh Poimboeuf (1): objtool: Add CONFIG_HAVE_UACCESS_VALIDATION
Peter Zijlstra (5): objtool: Mark __ubsan_handle_builtin_unreachable() as noreturn x86/cpu: Elide KCSAN for cpu_has() and friends jump_label,noinstr: Avoid instrumentation for JUMP_LABEL=n builds x86: Always inline on_thread_stack() and current_top_of_stack() context_tracking: Always inline empty stubs
arch/Kconfig | 4 ++++ arch/x86/Kconfig | 1 + arch/x86/include/asm/cpufeature.h | 2 +- arch/x86/include/asm/extable.h | 8 ++++++-- arch/x86/include/asm/processor.h | 4 ++-- include/linux/context_tracking_state.h | 8 ++++---- include/linux/jump_label.h | 4 ++-- scripts/Makefile.build | 2 +- scripts/link-vmlinux.sh | 4 +++- tools/objtool/check.c | 4 +++- 10 files changed, 27 insertions(+), 14 deletions(-)
diff --git a/arch/Kconfig b/arch/Kconfig index 904ed51736d4..cb2954027d10 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -1050,6 +1050,10 @@ config HAVE_NOINSTR_HACK config HAVE_NOINSTR_VALIDATION bool +config HAVE_UACCESS_VALIDATION + bool + select OBJTOOL + config HAVE_STACK_VALIDATION bool help diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index cf531fbcd229..5f41f3c3df9a 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -258,6 +258,7 @@ config X86 select HAVE_PREEMPT_DYNAMIC_CALL select HAVE_RSEQ select HAVE_SYSCALL_TRACEPOINTS + select HAVE_UACCESS_VALIDATION if HAVE_OBJTOOL select HAVE_UNSTABLE_SCHED_CLOCK select HAVE_USER_RETURN_NOTIFIER select HAVE_GENERIC_VDSO diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index 66d3e3b1d24d..ea34cc31b047 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -54,7 +54,7 @@ extern const char * const x86_power_flags[32]; extern const char * const x86_bug_flags[NBUGINTS*32]; #define test_cpu_cap(c, bit) \ - test_bit(bit, (unsigned long *)((c)->x86_capability)) + arch_test_bit(bit, (unsigned long *)((c)->x86_capability)) /* * There are 32 bits/features in each mask word. The high bits diff --git a/arch/x86/include/asm/extable.h b/arch/x86/include/asm/extable.h index 155c991ba95e..eeed395c3177 100644 --- a/arch/x86/include/asm/extable.h +++ b/arch/x86/include/asm/extable.h @@ -42,9 +42,13 @@ extern int ex_get_fixup_type(unsigned long ip); extern void early_fixup_exception(struct pt_regs *regs, int trapnr); #ifdef CONFIG_X86_MCE -extern void ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr); +extern void __noreturn ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr); #else -static inline void ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr) { } +static inline void __noreturn ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr) +{ + for (;;) + cpu_relax(); +} #endif #if defined(CONFIG_BPF_JIT) && defined(CONFIG_X86_64) diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 91d0f93a00c7..356308c73951 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -559,7 +559,7 @@ static __always_inline void native_swapgs(void) #endif } -static inline unsigned long current_top_of_stack(void) +static __always_inline unsigned long current_top_of_stack(void) { /* * We can't read directly from tss.sp0: sp0 on x86_32 is special in @@ -569,7 +569,7 @@ static inline unsigned long current_top_of_stack(void) return this_cpu_read_stable(cpu_current_top_of_stack); } -static inline bool on_thread_stack(void) +static __always_inline bool on_thread_stack(void) { return (unsigned long)(current_top_of_stack() - current_stack_pointer) < THREAD_SIZE; diff --git a/include/linux/context_tracking_state.h b/include/linux/context_tracking_state.h index 65a60d3313b0..ae1e63e26947 100644 --- a/include/linux/context_tracking_state.h +++ b/include/linux/context_tracking_state.h @@ -46,10 +46,10 @@ static __always_inline bool context_tracking_in_user(void) return __this_cpu_read(context_tracking.state) == CONTEXT_USER; } #else -static inline bool context_tracking_in_user(void) { return false; } -static inline bool context_tracking_enabled(void) { return false; } -static inline bool context_tracking_enabled_cpu(int cpu) { return false; } -static inline bool context_tracking_enabled_this_cpu(void) { return false; } +static __always_inline bool context_tracking_in_user(void) { return false; } +static __always_inline bool context_tracking_enabled(void) { return false; } +static __always_inline bool context_tracking_enabled_cpu(int cpu) { return false; } +static __always_inline bool context_tracking_enabled_this_cpu(void) { return false; } #endif /* CONFIG_CONTEXT_TRACKING */ #endif diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index 107751cc047b..bf1eef337a07 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -256,9 +256,9 @@ extern void static_key_disable_cpuslocked(struct static_key *key); #include <linux/atomic.h> #include <linux/bug.h> -static inline int static_key_count(struct static_key *key) +static __always_inline int static_key_count(struct static_key *key) { - return atomic_read(&key->enabled); + return arch_atomic_read(&key->enabled); } static __always_inline void jump_label_init(void) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index 06400504150b..6a663b27b286 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -218,7 +218,7 @@ objtool_args = \ $(if $(CONFIG_SLS), --sls) \ $(if $(CONFIG_STACK_VALIDATION), --stackval) \ $(if $(CONFIG_HAVE_STATIC_CALL_INLINE), --static-call) \ - --uaccess \ + $(if $(CONFIG_HAVE_UACCESS_VALIDATION), --uaccess) \ $(if $(linked-object), --link) \ $(if $(part-of-module), --module) \ $(if $(CONFIG_GCOV_KERNEL), --no-unreachable) diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh index a7f6196c7e41..fd578c380919 100755 --- a/scripts/link-vmlinux.sh +++ b/scripts/link-vmlinux.sh @@ -134,7 +134,9 @@ objtool_link() objtoolopt="${objtoolopt} --static-call" fi - objtoolopt="${objtoolopt} --uaccess" + if is_enabled CONFIG_HAVE_UACCESS_VALIDATION; then + objtoolopt="${objtoolopt} --uaccess" + fi fi if is_enabled CONFIG_NOINSTR_VALIDATION; then diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 190b2f6e360a..864bb9dd3584 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -185,7 +185,9 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func, "do_group_exit", "stop_this_cpu", "__invalid_creds", - "cpu_startup_entry", + "cpu_startup_entry", + "__ubsan_handle_builtin_unreachable", + "ex_handler_msr_mce", }; if (!func)
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