diff options
| author | Jordy Zomer <jordy@pwning.systems> | 2022-01-11 17:44:51 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-01-12 14:17:45 +0000 |
| commit | 4fbcc1a4cb20fe26ad0225679c536c80f1648221 (patch) | |
| tree | 229ddb89541415682459fce4f0934257016984d2 /drivers/nfc | |
| parent | 2a4d75bfe41232608f5596a6d1369f92ccb20817 (diff) | |
| download | lwn-4fbcc1a4cb20fe26ad0225679c536c80f1648221.tar.gz lwn-4fbcc1a4cb20fe26ad0225679c536c80f1648221.zip | |
nfc: st21nfca: Fix potential buffer overflows in EVT_TRANSACTION
It appears that there are some buffer overflows in EVT_TRANSACTION.
This happens because the length parameters that are passed to memcpy
come directly from skb->data and are not guarded in any way.
Signed-off-by: Jordy Zomer <jordy@pwning.systems>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/nfc')
| -rw-r--r-- | drivers/nfc/st21nfca/se.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/nfc/st21nfca/se.c b/drivers/nfc/st21nfca/se.c index a43fc4117fa5..c922f10d0d7b 100644 --- a/drivers/nfc/st21nfca/se.c +++ b/drivers/nfc/st21nfca/se.c @@ -316,6 +316,11 @@ int st21nfca_connectivity_event_received(struct nfc_hci_dev *hdev, u8 host, return -ENOMEM; transaction->aid_len = skb->data[1]; + + /* Checking if the length of the AID is valid */ + if (transaction->aid_len > sizeof(transaction->aid)) + return -EINVAL; + memcpy(transaction->aid, &skb->data[2], transaction->aid_len); @@ -325,6 +330,11 @@ int st21nfca_connectivity_event_received(struct nfc_hci_dev *hdev, u8 host, return -EPROTO; transaction->params_len = skb->data[transaction->aid_len + 3]; + + /* Total size is allocated (skb->len - 2) minus fixed array members */ + if (transaction->params_len > ((skb->len - 2) - sizeof(struct nfc_evt_transaction))) + return -EINVAL; + memcpy(transaction->params, skb->data + transaction->aid_len + 4, transaction->params_len); |