scsi: qla4xxx: Add length check when parsing nlattrs

There are three places that qla4xxx parses nlattrs:

 - qla4xxx_set_chap_entry()

 - qla4xxx_iface_set_param()

 - qla4xxx_sysfs_ddb_set_param()

and each of them directly converts the nlattr to specific pointer of
structure without length checking. This could be dangerous as those
attributes are not validated and a malformed nlattr (e.g., length 0) could
result in an OOB read that leaks heap dirty data.

Add the nla_len check before accessing the nlattr data and return EINVAL if
the length check fails.

Fixes: 26ffd7b45fe9 ("[SCSI] qla4xxx: Add support to set CHAP entries")
Fixes: 1e9e2be3ee03 ("[SCSI] qla4xxx: Add flash node mgmt support")
Fixes: 00c31889f751 ("[SCSI] qla4xxx: fix data alignment and use nl helpers")
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Link: https://lore.kernel.org/r/20230723080053.3714534-1-linma@zju.edu.cn
Reviewed-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/qla4xxx/ql4_os.c b/drivers/scsi/qla4xxx/ql4_os.c
index b2a3988e1e1594603307f19dd43d87ec33398d0e..675332e49a7b063c54c3d265e5f56006f59ffa8a 100644 (file)
--- a/drivers/scsi/qla4xxx/ql4_os.c
+++ b/drivers/scsi/qla4xxx/ql4_os.c
@@ -968,6 +968,11 @@ static int qla4xxx_set_chap_entry(struct Scsi_Host *shost, void *data, int len)
        memset(&chap_rec, 0, sizeof(chap_rec));
 
        nla_for_each_attr(attr, data, len, rem) {
+               if (nla_len(attr) < sizeof(*param_info)) {
+                       rc = -EINVAL;
+                       goto exit_set_chap;
+               }
+
                param_info = nla_data(attr);
 
                switch (param_info->param) {
@@ -2750,6 +2755,11 @@ qla4xxx_iface_set_param(struct Scsi_Host *shost, void *data, uint32_t len)
        }
 
        nla_for_each_attr(attr, data, len, rem) {
+               if (nla_len(attr) < sizeof(*iface_param)) {
+                       rval = -EINVAL;
+                       goto exit_init_fw_cb;
+               }
+
                iface_param = nla_data(attr);
 
                if (iface_param->param_type == ISCSI_NET_PARAM) {
@@ -8104,6 +8114,11 @@ qla4xxx_sysfs_ddb_set_param(struct iscsi_bus_flash_session *fnode_sess,
 
        memset((void *)&chap_tbl, 0, sizeof(chap_tbl));
        nla_for_each_attr(attr, data, len, rem) {
+               if (nla_len(attr) < sizeof(*fnode_param)) {
+                       rc = -EINVAL;
+                       goto exit_set_param;
+               }
+
                fnode_param = nla_data(attr);
 
                switch (fnode_param->param) {