task_work: Call tracehook_notify_signal from get_signal on all architectures

Always handle TIF_NOTIFY_SIGNAL in get_signal.  With commit 35d0b389f3
("task_work: unconditionally run task_work from get_signal()") always
calling task_work_run all of the work of tracehook_notify_signal is
already happening except clearing TIF_NOTIFY_SIGNAL.

Factor clear_notify_signal out of tracehook_notify_signal and use it in
get_signal so that get_signal only needs one call of task_work_run.

To keep the semantics in sync update xfer_to_guest_mode_work (which
does not call get_signal) to call tracehook_notify_signal if either
_TIF_SIGPENDING or _TIF_NOTIFY_SIGNAL.

Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20220309162454.123006-8-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This commit is contained in:
Eric W. Biederman
2022-02-09 09:51:14 -06:00
parent 7f62d40d9c
commit 8ba62d3794
7 changed files with 18 additions and 29 deletions

View File

@@ -139,15 +139,7 @@ void noinstr exit_to_user_mode(void)
}
/* Workaround to allow gradual conversion of architecture code */
void __weak arch_do_signal_or_restart(struct pt_regs *regs, bool has_signal) { }
static void handle_signal_work(struct pt_regs *regs, unsigned long ti_work)
{
if (ti_work & _TIF_NOTIFY_SIGNAL)
tracehook_notify_signal();
arch_do_signal_or_restart(regs, ti_work & _TIF_SIGPENDING);
}
void __weak arch_do_signal_or_restart(struct pt_regs *regs) { }
static unsigned long exit_to_user_mode_loop(struct pt_regs *regs,
unsigned long ti_work)
@@ -170,7 +162,7 @@ static unsigned long exit_to_user_mode_loop(struct pt_regs *regs,
klp_update_patch_state(current);
if (ti_work & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL))
handle_signal_work(regs, ti_work);
arch_do_signal_or_restart(regs);
if (ti_work & _TIF_NOTIFY_RESUME)
tracehook_notify_resume(regs);

View File

@@ -8,7 +8,7 @@ static int xfer_to_guest_mode_work(struct kvm_vcpu *vcpu, unsigned long ti_work)
do {
int ret;
if (ti_work & _TIF_NOTIFY_SIGNAL)
if (ti_work & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL))
tracehook_notify_signal();
if (ti_work & _TIF_SIGPENDING) {