diff mbox

drviers/md: fix max dup length for kstrndup

Message ID 20171212093910.21743-1-mashimiao.fnst@cn.fujitsu.com (mailing list archive)
State Accepted, archived
Delegated to: Mike Snitzer
Headers show

Commit Message

Ma Shimiao Dec. 12, 2017, 9:39 a.m. UTC 
If source string longer than max, kstrndup will alloc max+1 space.
So, we should make sure the result will not over limit.

Signed-off-by: Ma Shimiao <mashimiao.fnst@cn.fujitsu.com>
---
 drivers/md/dm-log-writes.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox

Patch

diff --git a/drivers/md/dm-log-writes.c b/drivers/md/dm-log-writes.c
index 189badbeddaf..3362d866793b 100644
--- a/drivers/md/dm-log-writes.c
+++ b/drivers/md/dm-log-writes.c
@@ -594,7 +594,7 @@  static int log_mark(struct log_writes_c *lc, char *data)
 		return -ENOMEM;
 	}
 
-	block->data = kstrndup(data, maxsize, GFP_KERNEL);
+	block->data = kstrndup(data, maxsize - 1, GFP_KERNEL);
 	if (!block->data) {
 		DMERR("Error copying mark data");
 		kfree(block);