From: Jens Axboe axboe@kernel.dk
stable inclusion from stable-v5.10.162 commit 52cfde6bbf64f7f058efa805c6dbb6332d4de6fa category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...
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[ Upstream commit 5c251e9dc0e127bac6fc5b8e6696363d2e35f515 ]
This is in preparation for maintaining signal_pending() as the decider of whether or not a schedule() loop should be broken, or continue sleeping. This is different than the core signal use cases, which really need to know whether an actual signal is pending or not. task_sigpending() returns non-zero if TIF_SIGPENDING is set.
Only core kernel use cases should care about the distinction between the two, make sure those use the task_sigpending() helper.
Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Thomas Gleixner tglx@linutronix.de Reviewed-by: Thomas Gleixner tglx@linutronix.de Reviewed-by: Oleg Nesterov oleg@redhat.com Link: https://lore.kernel.org/r/20201026203230.386348-2-axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- include/linux/sched/signal.h | 9 +++++++-- kernel/events/uprobes.c | 2 +- kernel/signal.c | 8 ++++---- 3 files changed, 12 insertions(+), 7 deletions(-)
diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h index 940be421d263..00966c66a17c 100644 --- a/include/linux/sched/signal.h +++ b/include/linux/sched/signal.h @@ -360,11 +360,16 @@ static inline int restart_syscall(void) return -ERESTARTNOINTR; }
-static inline int signal_pending(struct task_struct *p) +static inline int task_sigpending(struct task_struct *p) { return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); }
+static inline int signal_pending(struct task_struct *p) +{ + return task_sigpending(p); +} + static inline int __fatal_signal_pending(struct task_struct *p) { return unlikely(sigismember(&p->pending.signal, SIGKILL)); @@ -372,7 +377,7 @@ static inline int __fatal_signal_pending(struct task_struct *p)
static inline int fatal_signal_pending(struct task_struct *p) { - return signal_pending(p) && __fatal_signal_pending(p); + return task_sigpending(p) && __fatal_signal_pending(p); }
static inline int signal_pending_state(long state, struct task_struct *p) diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index fc5875257e6d..6fdf0ace8aa3 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1973,7 +1973,7 @@ bool uprobe_deny_signal(void)
WARN_ON_ONCE(utask->state != UTASK_SSTEP);
- if (signal_pending(t)) { + if (task_sigpending(t)) { spin_lock_irq(&t->sighand->siglock); clear_tsk_thread_flag(t, TIF_SIGPENDING); spin_unlock_irq(&t->sighand->siglock); diff --git a/kernel/signal.c b/kernel/signal.c index d874c96315a6..c704b7a40628 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -986,7 +986,7 @@ static inline bool wants_signal(int sig, struct task_struct *p) if (task_is_stopped_or_traced(p)) return false;
- return task_curr(p) || !signal_pending(p); + return task_curr(p) || !task_sigpending(p); }
static void complete_signal(int sig, struct task_struct *p, enum pid_type type) @@ -2819,7 +2819,7 @@ static void retarget_shared_pending(struct task_struct *tsk, sigset_t *which) /* Remove the signals this thread can handle. */ sigandsets(&retarget, &retarget, &t->blocked);
- if (!signal_pending(t)) + if (!task_sigpending(t)) signal_wake_up(t, 0);
if (sigisemptyset(&retarget)) @@ -2853,7 +2853,7 @@ void exit_signals(struct task_struct *tsk)
cgroup_threadgroup_change_end(tsk);
- if (!signal_pending(tsk)) + if (!task_sigpending(tsk)) goto out;
unblocked = tsk->blocked; @@ -2897,7 +2897,7 @@ long do_no_restart_syscall(struct restart_block *param)
static void __set_task_blocked(struct task_struct *tsk, const sigset_t *newset) { - if (signal_pending(tsk) && !thread_group_empty(tsk)) { + if (task_sigpending(tsk) && !thread_group_empty(tsk)) { sigset_t newblocked; /* A set of now blocked but previously unblocked signals. */ sigandnsets(&newblocked, newset, ¤t->blocked);