Commit 86e5908e authored by wuchi's avatar wuchi Committed by Andrew Morton
Browse files

lib/error-inject: traverse list with mutex 

Traversing list without mutex in get_injectable_error_type will
race with the following code:
    list_del_init(&ent->list)
    kfree(ent)
in module_unload_ei_list. So fix that.

Link: https://lkml.kernel.org/r/20220620100244.82896-1-wuchi.zero@gmail.com


Signed-off-by: default avatarwuchi <wuchi.zero@gmail.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent f9987921

lib/error-inject.c

+9 −3
Original line number Diff line number Diff line
@@ -40,12 +40,18 @@ bool within_error_injection_list(unsigned long addr) 
int get_injectable_error_type(unsigned long addr)

{

	struct ei_entry *ent;

	int ei_type = EI_ETYPE_NONE;



	mutex_lock(&ei_mutex);

	list_for_each_entry(ent, &error_injection_list, list) {

		if (addr >= ent->start_addr && addr < ent->end_addr)

			return ent->etype;

		if (addr >= ent->start_addr && addr < ent->end_addr) {

			ei_type = ent->etype;

			break;

		}

	return EI_ETYPE_NONE;

	}

	mutex_unlock(&ei_mutex);



	return ei_type;

}



/*