diff options
Diffstat (limited to 'arch/x86_64/kernel/traps.c')
| -rw-r--r-- | arch/x86_64/kernel/traps.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c index 7819022a8db..0d65b22f229 100644 --- a/arch/x86_64/kernel/traps.c +++ b/arch/x86_64/kernel/traps.c @@ -242,12 +242,19 @@ static int dump_trace_unwind(struct unwind_frame_info *info, void *context) * severe exception (double fault, nmi, stack fault, debug, mce) hardware stack */ +static inline int valid_stack_ptr(struct thread_info *tinfo, void *p) +{ + void *t = (void *)tinfo; + return p > t && p < t + THREAD_SIZE - 3; +} + void dump_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long * stack, struct stacktrace_ops *ops, void *data) { const unsigned cpu = smp_processor_id(); unsigned long *irqstack_end = (unsigned long *)cpu_pda(cpu)->irqstackptr; unsigned used = 0; + struct thread_info *tinfo; if (!tsk) tsk = current; @@ -290,6 +297,12 @@ void dump_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long * s if (tsk && tsk != current) stack = (unsigned long *)tsk->thread.rsp; } + /* + * Align the stack pointer on word boundary, later loops + * rely on that (and corruption / debug info bugs can cause + * unaligned values here): + */ + stack = (unsigned long *)((unsigned long)stack & ~(sizeof(long)-1)); /* * Print function call entries within a stack. 'cond' is the @@ -364,7 +377,8 @@ void dump_trace(struct task_struct *tsk, struct pt_regs *regs, unsigned long * s /* * This handles the process stack: */ - HANDLE_STACK (((long) stack & (THREAD_SIZE-1)) != 0); + tinfo = current_thread_info(); + HANDLE_STACK (valid_stack_ptr(tinfo, stack)); #undef HANDLE_STACK } EXPORT_SYMBOL(dump_trace); |