Commit 9478af9b authored by Zheng Yejian's avatar Zheng Yejian
Browse files

livepatch/powerpc: Add arch_klp_module_check_calltrace 

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8MGE6



--------------------------------

Add arch_klp_module_check_calltrace to check whether stacks of all tasks
are within the code segment of module.

Signed-off-by: default avatarYang Jihong <yangjihong1@huawei.com>
Signed-off-by: default avatarZheng Yejian <zhengyejian1@huawei.com>
parent 7213e5d7

arch/powerpc/include/asm/livepatch.h

+1 −0
Original line number Diff line number Diff line
@@ -96,6 +96,7 @@ int klp_patch_text(u32 *dst, const u32 *src, int len); 
int klp_brk_handler(struct pt_regs *regs);

int arch_klp_add_breakpoint(struct arch_klp_data *arch_data, void *old_func);

void arch_klp_remove_breakpoint(struct arch_klp_data *arch_data, void *old_func);

int arch_klp_module_check_calltrace(void *data);



#endif /* CONFIG_LIVEPATCH_WO_FTRACE */

arch/powerpc/kernel/livepatch.c

+33 −0
Original line number Diff line number Diff line
@@ -261,6 +261,39 @@ int arch_klp_check_calltrace(bool (*check_func)(void *, int *, unsigned long), v 
	return do_check_calltrace(&args, klp_check_jump_func);

}



static int klp_check_module_calltrace(struct stackframe *frame, void *ws_args)

{

	struct walk_stackframe_args *args = ws_args;

	struct module *mod = args->data;



	/* check NIP when the exception stack switching */

	if (frame->nip && within_module_core(frame->nip, mod))

		goto err_out;

	if (frame->link && !frame->nip_link_in_same_func &&

	    within_module_core(frame->link, mod))

		goto err_out;

	if (!frame->is_top_frame || frame->nip_link_in_same_func) {

		if (within_module_core(frame->pc, mod))

			goto err_out;

	}



	return 0;



err_out:

	pr_err("module %s is in use!\n", mod->name);

	return (args->ret = -EBUSY);

}



int arch_klp_module_check_calltrace(void *data)

{

	struct walk_stackframe_args args = {

		.data = data,

		.ret = 0

	};



	return do_check_calltrace(&args, klp_check_module_calltrace);

}



int klp_patch_text(u32 *dst, const u32 *src, int len)

{

	int i;