exofs: Cap on the memcpy() size

This data comes from the device, so probably it's fairly trustworthy but
it makes the static checkers happy if we check it.

[Boaz]
  the system_id_len is zero, if not present, or always OSD_SYSTEMID_LEN.
  So always copy OSD_SYSTEMID_LEN bytes.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/exofs/super.c b/fs/exofs/super.c
index d9619a577806..6c5397ad7a2a 100644
--- a/fs/exofs/super.c
+++ b/fs/exofs/super.c
@@ -529,7 +529,8 @@ static int exofs_devs_2_odi(struct exofs_dt_device_info *dt_dev,
                              struct osd_dev_info *odi)
 {
         odi->systemid_len = le32_to_cpu(dt_dev->systemid_len);
-        memcpy(odi->systemid, dt_dev->systemid, odi->systemid_len);
+        if (likely(odi->systemid_len))
+                memcpy(odi->systemid, dt_dev->systemid, OSD_SYSTEMID_LEN);
 
         odi->osdname_len = le32_to_cpu(dt_dev->osdname_len);
         odi->osdname = dt_dev->osdname;