diff options
| -rw-r--r-- | arch/x86/kernel/alternative.c | 9 | ||||
| -rw-r--r-- | arch/x86/kernel/dumpstack.c | 23 |
2 files changed, 24 insertions, 8 deletions
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 9f354ebf76e4..e377b06e70e3 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -541,7 +541,7 @@ EXPORT_SYMBOL(BUG_func); * Rewrite the "call BUG_func" replacement to point to the target of the * indirect pv_ops call "call *disp(%ip)". */ -static int alt_replace_call(u8 *instr, u8 *insn_buff, struct alt_instr *a) +static unsigned int alt_replace_call(u8 *instr, u8 *insn_buff, struct alt_instr *a) { void *target, *bug = &BUG_func; s32 disp; @@ -625,7 +625,7 @@ void __init_or_module noinline apply_alternatives(struct alt_instr *start, * order. */ for (a = start; a < end; a++) { - int insn_buff_sz = 0; + unsigned int insn_buff_sz = 0; /* * In case of nested ALTERNATIVE()s the outer alternative might @@ -665,11 +665,8 @@ void __init_or_module noinline apply_alternatives(struct alt_instr *start, memcpy(insn_buff, replacement, a->replacementlen); insn_buff_sz = a->replacementlen; - if (a->flags & ALT_FLAG_DIRECT_CALL) { + if (a->flags & ALT_FLAG_DIRECT_CALL) insn_buff_sz = alt_replace_call(instr, insn_buff, a); - if (insn_buff_sz < 0) - continue; - } for (; insn_buff_sz < a->instrlen; insn_buff_sz++) insn_buff[insn_buff_sz] = 0x90; diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c index 71ee20102a8a..b10684dedc58 100644 --- a/arch/x86/kernel/dumpstack.c +++ b/arch/x86/kernel/dumpstack.c @@ -181,8 +181,8 @@ static void show_regs_if_on_stack(struct stack_info *info, struct pt_regs *regs, * in false positive reports. Disable instrumentation to avoid those. */ __no_kmsan_checks -static void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs, - unsigned long *stack, const char *log_lvl) +static void __show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs, + unsigned long *stack, const char *log_lvl) { struct unwind_state state; struct stack_info stack_info = {0}; @@ -303,6 +303,25 @@ next: } } +static void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs, + unsigned long *stack, const char *log_lvl) +{ + /* + * Disable KASAN to avoid false positives during walking another + * task's stacks, as values on these stacks may change concurrently + * with task execution. + */ + bool disable_kasan = task && task != current; + + if (disable_kasan) + kasan_disable_current(); + + __show_trace_log_lvl(task, regs, stack, log_lvl); + + if (disable_kasan) + kasan_enable_current(); +} + void show_stack(struct task_struct *task, unsigned long *sp, const char *loglvl) { |