[PATCH 04/11] timers: Rename del_timer() to timer_delete()

[Yuxuan Luo]

From: Thomas Gleixner <tglx at linutronix.de>

The timer related functions do not have a strict timer_ prefixed namespace
which is really annoying.

Rename del_timer() to timer_delete() and provide del_timer()
as a wrapper. Document that del_timer() is not for new code.

Signed-off-by: Thomas Gleixner <tglx at linutronix.de>
Tested-by: Guenter Roeck <linux at roeck-us.net>
Reviewed-by: Steven Rostedt (Google) <rostedt at goodmis.org>
Reviewed-by: Jacob Keller <jacob.e.keller at intel.com>
Reviewed-by: Anna-Maria Behnsen <anna-maria at linutronix.de>
Link: https://lore.kernel.org/r/20221123201625.015535022@linutronix.de

(backported from commit bb663f0f3c396c6d05f6c5eeeea96ced20ff112e)
[yuxuan.luo: ignored the conflict and added the new content]
CVE-2023-6039
Signed-off-by: Yuxuan Luo <yuxuan.luo at canonical.com>
---
 include/linux/timer.h | 15 ++++++++++++++-
 kernel/time/timer.c   |  6 +++---
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/include/linux/timer.h b/include/linux/timer.h
index e78521bce565a..4ac94c208d3c2 100644
--- a/include/linux/timer.h
+++ b/include/linux/timer.h
@@ -169,7 +169,6 @@ static inline int timer_pending(const struct timer_list * timer)
 }
 
 extern void add_timer_on(struct timer_list *timer, int cpu);
-extern int del_timer(struct timer_list * timer);
 extern int mod_timer(struct timer_list *timer, unsigned long expires);
 extern int mod_timer_pending(struct timer_list *timer, unsigned long expires);
 extern int timer_reduce(struct timer_list *timer, unsigned long expires);
@@ -184,6 +183,7 @@ extern void add_timer(struct timer_list *timer);
 
 extern int try_to_del_timer_sync(struct timer_list *timer);
 extern int timer_delete_sync(struct timer_list *timer);
+extern int timer_delete(struct timer_list *timer);
 
 /**
  * del_timer_sync - Delete a pending timer and wait for a running callback
@@ -200,6 +200,19 @@ static inline int del_timer_sync(struct timer_list *timer)
 
 #define del_singleshot_timer_sync(t) del_timer_sync(t)
 
+/**
+ * del_timer - Delete a pending timer
+ * @timer:	The timer to be deleted
+ *
+ * See timer_delete() for detailed explanation.
+ *
+ * Do not use in new code. Use timer_delete() instead.
+ */
+static inline int del_timer(struct timer_list *timer)
+{
+	return timer_delete(timer);
+}
+
 extern void init_timers(void);
 struct hrtimer;
 extern enum hrtimer_restart it_real_fn(struct hrtimer *);
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index d4ce3ebe2c8cf..9016721ff25e0 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -1202,7 +1202,7 @@ void add_timer_on(struct timer_list *timer, int cpu)
 EXPORT_SYMBOL_GPL(add_timer_on);
 
 /**
- * del_timer - Deactivate a timer.
+ * timer_delete - Deactivate a timer
  * @timer:	The timer to be deactivated
  *
  * The function only deactivates a pending timer, but contrary to
@@ -1215,7 +1215,7 @@ EXPORT_SYMBOL_GPL(add_timer_on);
  * * %0 - The timer was not pending
  * * %1 - The timer was pending and deactivated
  */
-int del_timer(struct timer_list *timer)
+int timer_delete(struct timer_list *timer)
 {
 	struct timer_base *base;
 	unsigned long flags;
@@ -1231,7 +1231,7 @@ int del_timer(struct timer_list *timer)
 
 	return ret;
 }
-EXPORT_SYMBOL(del_timer);
+EXPORT_SYMBOL(timer_delete);
 
 /**
  * try_to_del_timer_sync - Try to deactivate a timer
-- 
2.34.1