[PATCH 1/1] ipmi_si_intf: Fix race in timer shutdown handling

From: Jes Sorensen
Date: Wed Aug 28 2019 - 16:36:39 EST


From: Jes Sorensen <jsorensen@xxxxxx>

smi_mod_timer() enables the timer before setting timer_running. This
means the timer can be running when we get to stop_timer_and_thread()
without timer_running having been set, resulting in del_timer_sync()
not being called and the timer being left to cause havoc during
shutdown.

Instead just call del_timer_sync() unconditionally

Signed-off-by: Jes Sorensen <jsorensen@xxxxxx>
---
drivers/char/ipmi/ipmi_si_intf.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
index da5b6723329a..53425e25ecf4 100644
--- a/drivers/char/ipmi/ipmi_si_intf.c
+++ b/drivers/char/ipmi/ipmi_si_intf.c
@@ -1828,8 +1828,7 @@ static inline void stop_timer_and_thread(struct smi_info *smi_info)
}

smi_info->timer_can_start = false;
- if (smi_info->timer_running)
- del_timer_sync(&smi_info->si_timer);
+ del_timer_sync(&smi_info->si_timer);
}

static struct smi_info *find_dup_si(struct smi_info *info)
--
2.21.0