mirror of
https://github.com/torvalds/linux.git
synced 2025-11-04 02:30:34 +02:00
36903abedf
The __range_not_ok() helper is an x86 (and sparc64) specific interface that does roughly the same thing as __access_ok(), but with different calling conventions. Change this to use the normal interface in order for consistency as we clean up all access_ok() implementations. This changes the limit from TASK_SIZE to TASK_SIZE_MAX, which Al points out is the right thing do do here anyway. The callers have to use __access_ok() instead of the normal access_ok() though, because on x86 that contains a WARN_ON_IN_IRQ() check that cannot be used inside of NMI context while tracing. The check in copy_code() is not needed any more, because this one is already done by copy_from_user_nmi(). Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Suggested-by: Christoph Hellwig <hch@infradead.org> Link: https://lore.kernel.org/lkml/YgsUKcXGR7r4nINj@zeniv-ca.linux.org.uk/ Signed-off-by: Arnd Bergmann <arnd@arndb.de>
130 lines
2.9 KiB
C
130 lines
2.9 KiB
C
/*
|
|
* Stack trace management functions
|
|
*
|
|
* Copyright (C) 2006-2009 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
|
|
*/
|
|
#include <linux/sched.h>
|
|
#include <linux/sched/debug.h>
|
|
#include <linux/sched/task_stack.h>
|
|
#include <linux/stacktrace.h>
|
|
#include <linux/export.h>
|
|
#include <linux/uaccess.h>
|
|
#include <asm/stacktrace.h>
|
|
#include <asm/unwind.h>
|
|
|
|
void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie,
|
|
struct task_struct *task, struct pt_regs *regs)
|
|
{
|
|
struct unwind_state state;
|
|
unsigned long addr;
|
|
|
|
if (regs && !consume_entry(cookie, regs->ip))
|
|
return;
|
|
|
|
for (unwind_start(&state, task, regs, NULL); !unwind_done(&state);
|
|
unwind_next_frame(&state)) {
|
|
addr = unwind_get_return_address(&state);
|
|
if (!addr || !consume_entry(cookie, addr))
|
|
break;
|
|
}
|
|
}
|
|
|
|
int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry,
|
|
void *cookie, struct task_struct *task)
|
|
{
|
|
struct unwind_state state;
|
|
struct pt_regs *regs;
|
|
unsigned long addr;
|
|
|
|
for (unwind_start(&state, task, NULL, NULL);
|
|
!unwind_done(&state) && !unwind_error(&state);
|
|
unwind_next_frame(&state)) {
|
|
|
|
regs = unwind_get_entry_regs(&state, NULL);
|
|
if (regs) {
|
|
/* Success path for user tasks */
|
|
if (user_mode(regs))
|
|
return 0;
|
|
|
|
/*
|
|
* Kernel mode registers on the stack indicate an
|
|
* in-kernel interrupt or exception (e.g., preemption
|
|
* or a page fault), which can make frame pointers
|
|
* unreliable.
|
|
*/
|
|
if (IS_ENABLED(CONFIG_FRAME_POINTER))
|
|
return -EINVAL;
|
|
}
|
|
|
|
addr = unwind_get_return_address(&state);
|
|
|
|
/*
|
|
* A NULL or invalid return address probably means there's some
|
|
* generated code which __kernel_text_address() doesn't know
|
|
* about.
|
|
*/
|
|
if (!addr)
|
|
return -EINVAL;
|
|
|
|
if (!consume_entry(cookie, addr))
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Check for stack corruption */
|
|
if (unwind_error(&state))
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Userspace stacktrace - based on kernel/trace/trace_sysprof.c */
|
|
|
|
struct stack_frame_user {
|
|
const void __user *next_fp;
|
|
unsigned long ret_addr;
|
|
};
|
|
|
|
static int
|
|
copy_stack_frame(const struct stack_frame_user __user *fp,
|
|
struct stack_frame_user *frame)
|
|
{
|
|
int ret;
|
|
|
|
if (!__access_ok(fp, sizeof(*frame)))
|
|
return 0;
|
|
|
|
ret = 1;
|
|
pagefault_disable();
|
|
if (__get_user(frame->next_fp, &fp->next_fp) ||
|
|
__get_user(frame->ret_addr, &fp->ret_addr))
|
|
ret = 0;
|
|
pagefault_enable();
|
|
|
|
return ret;
|
|
}
|
|
|
|
void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie,
|
|
const struct pt_regs *regs)
|
|
{
|
|
const void __user *fp = (const void __user *)regs->bp;
|
|
|
|
if (!consume_entry(cookie, regs->ip))
|
|
return;
|
|
|
|
while (1) {
|
|
struct stack_frame_user frame;
|
|
|
|
frame.next_fp = NULL;
|
|
frame.ret_addr = 0;
|
|
if (!copy_stack_frame(fp, &frame))
|
|
break;
|
|
if ((unsigned long)fp < regs->sp)
|
|
break;
|
|
if (!frame.ret_addr)
|
|
break;
|
|
if (!consume_entry(cookie, frame.ret_addr))
|
|
break;
|
|
fp = frame.next_fp;
|
|
}
|
|
}
|
|
|