From b8d966efd9a46a9a35beac50cbff6e30565125ef Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Wed, 1 Jul 2009 11:14:04 +1000 Subject: [PATCH] md: avoid dereferencing NULL pointer when accessing suspend_* sysfs attributes. If we try to modify one of the md/ sysfs files suspend_lo or suspend_hi when the array is not active, we dereference a NULL. Protect against that. Cc: stable@kernel.org Signed-off-by: NeilBrown --- drivers/md/md.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 09be637d52cb..2166af8a7654 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -3573,7 +3573,8 @@ suspend_lo_store(mddev_t *mddev, const char *buf, size_t len) char *e; unsigned long long new = simple_strtoull(buf, &e, 10); - if (mddev->pers->quiesce == NULL) + if (mddev->pers == NULL || + mddev->pers->quiesce == NULL) return -EINVAL; if (buf == e || (*e && *e != '\n')) return -EINVAL; @@ -3601,7 +3602,8 @@ suspend_hi_store(mddev_t *mddev, const char *buf, size_t len) char *e; unsigned long long new = simple_strtoull(buf, &e, 10); - if (mddev->pers->quiesce == NULL) + if (mddev->pers == NULL || + mddev->pers->quiesce == NULL) return -EINVAL; if (buf == e || (*e && *e != '\n')) return -EINVAL;