From ae78eff333746326e630e505d7fac0d237e644ef Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 19 Oct 2026 19:23:18 -1000 Subject: [PATCH] compat: use scoped user access in get_compat_sigevent() get_compat_sigevent() does one access_ok() on the user structure and then reads four fields with __get_user(). Each of those reads enables and disables user access on its own, so the single range check no longer buys anything. Read the fields inside a scoped_user_read_access() instead. This is part of getting rid of __get_user() and __put_user() entirely. Signed-off-by: Linus Torvalds --- kernel/compat.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/kernel/compat.c b/kernel/compat.c index fb50f29d9b36..c754793c7d65 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -180,14 +180,18 @@ int get_compat_sigevent(struct sigevent *event, const struct compat_sigevent __user *u_event) { memset(event, 0, sizeof(*event)); - return (!access_ok(u_event, sizeof(*u_event)) || - __get_user(event->sigev_value.sival_int, - &u_event->sigev_value.sival_int) || - __get_user(event->sigev_signo, &u_event->sigev_signo) || - __get_user(event->sigev_notify, &u_event->sigev_notify) || - __get_user(event->sigev_notify_thread_id, - &u_event->sigev_notify_thread_id)) - ? -EFAULT : 0; + scoped_user_read_access(u_event, Efault) { + unsafe_get_user(event->sigev_value.sival_int, + &u_event->sigev_value.sival_int, Efault); + unsafe_get_user(event->sigev_signo, &u_event->sigev_signo, Efault); + unsafe_get_user(event->sigev_notify, &u_event->sigev_notify, Efault); + unsafe_get_user(event->sigev_notify_thread_id, + &u_event->sigev_notify_thread_id, Efault); + } + return 0; + +Efault: + return -EFAULT; } long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,