[PATCH AUTOSEL 5.4 29/50] net: ena: fix potential crash when rxfh key is NULL

Sasha Levin
2020-02-23T02:31:47Z

From: Arthur Kiyanovski <akiyano@amazon.com>

[ Upstream commit 91a65b7d3ed8450f31ab717a65dcb5f9ceb5ab02 ]

When ethtool -X is called without an hkey, ena_com_fill_hash_function()
is called with key=NULL, which is passed to memcpy causing a crash.

This commit fixes this issue by checking key is not NULL.

Fixes: 1738cd3ed342 ("net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)")
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/amazon/ena/ena_com.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_com.c b/drivers/net/ethernet/amazon/ena/ena_com.c
index ea62604fdf8ca..e54c44fdcaa73 100644
--- a/drivers/net/ethernet/amazon/ena/ena_com.c
+++ b/drivers/net/ethernet/amazon/ena/ena_com.c
@@ -2297,15 +2297,16 @@ int ena_com_fill_hash_function(struct ena_com_dev *ena_dev,

switch (func) {
case ENA_ADMIN_TOEPLITZ:
- if (key_len > sizeof(hash_key->key)) {
- pr_err("key len (%hu) is bigger than the max supported (%zu)\n",
- key_len, sizeof(hash_key->key));
- return -EINVAL;
+ if (key) {
+ if (key_len != sizeof(hash_key->key)) {
+ pr_err("key len (%hu) doesn't equal the supported size (%zu)\n",
+ key_len, sizeof(hash_key->key));
+ return -EINVAL;
+ }
+ memcpy(hash_key->key, key, key_len);
+ rss->hash_init_val = init_val;
+ hash_key->keys_num = key_len >> 2;
}
-
- memcpy(hash_key->key, key, key_len);
- rss->hash_init_val = init_val;
- hash_key->keys_num = key_len >> 2;
break;
case ENA_ADMIN_CRC32:
rss->hash_init_val = init_val;
--
2.20.1