livepatch: store function sizes

For the consistency model we'll need to know the sizes of the old and
new functions to determine if they're on the stacks of any tasks.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
Josh Poimboeuf 2017-02-13 19:42:39 -06:00 committed by Jiri Kosina
parent 68ae4b2b68
commit f5e547f4ac
2 changed files with 19 additions and 0 deletions

View file

@ -37,6 +37,8 @@
* @old_addr: the address of the function being patched
* @kobj: kobject for sysfs resources
* @stack_node: list node for klp_ops func_stack list
* @old_size: size of the old function
* @new_size: size of the new function
* @patched: the func has been added to the klp_ops list
*/
struct klp_func {
@ -56,6 +58,7 @@ struct klp_func {
unsigned long old_addr;
struct kobject kobj;
struct list_head stack_node;
unsigned long old_size, new_size;
bool patched;
};

View file

@ -584,6 +584,22 @@ static int klp_init_object_loaded(struct klp_patch *patch,
&func->old_addr);
if (ret)
return ret;
ret = kallsyms_lookup_size_offset(func->old_addr,
&func->old_size, NULL);
if (!ret) {
pr_err("kallsyms size lookup failed for '%s'\n",
func->old_name);
return -ENOENT;
}
ret = kallsyms_lookup_size_offset((unsigned long)func->new_func,
&func->new_size, NULL);
if (!ret) {
pr_err("kallsyms size lookup failed for '%s' replacement\n",
func->old_name);
return -ENOENT;
}
}
return 0;