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 <neilb@suse.de>
This commit is contained in:
NeilBrown 2009-07-01 11:14:04 +10:00
parent 8f6c2e4b32
commit b8d966efd9

View file

@ -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;