Control Flow Integrity(CFI) is a security mechanism that disallows
changes to the original control flow graph of a compiled binary,
making it significantly harder to perform such attacks.
init_state_node() assign same function callback to different
function pointer declarations.
static int init_state_node(struct cpuidle_state *idle_state,
const struct of_device_id *matches,
struct device_node *state_node) { ...
idle_state->enter = match_id->data; ...
idle_state->enter_s2idle = match_id->data; }
Function declarations:
struct cpuidle_state { ...
int (*enter) (struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index);
void (*enter_s2idle) (struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index); };
In this case, either enter() or enter_s2idle() would cause CFI check
failed since they use same callee.
Align function prototype of enter() since it needs return value for
some use cases. The return value of enter_s2idle() is no
need currently.
Bug: 159445192
Bug: 159672235
Change-Id: Iffc9e1b6a17471ca4291865ab3dc8803303a38ce
Link: https://lore.kernel.org/lkml/1595820346-4361-2-git-send-email-neal.liu@mediatek.com/
Signed-off-by: Neal Liu <neal.liu@mediatek.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
476c942d9b