x86, microcode, AMD: Fix use after free in free_cache()
list_for_each_entry_reverse() dereferences the iterator, but we already
freed it. I don't see a reason that this has to be done in reverse order
so change it to use list_for_each_entry_safe().
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 5511216..7720ff5 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -150,9 +150,9 @@
static void free_cache(void)
{
- struct ucode_patch *p;
+ struct ucode_patch *p, *tmp;
- list_for_each_entry_reverse(p, &pcache, plist) {
+ list_for_each_entry_safe(p, tmp, &pcache, plist) {
__list_del(p->plist.prev, p->plist.next);
kfree(p->data);
kfree(p);