orinoco: Avoid field-overflowing memcpy()

In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memcpy(), memmove(), and memset(), avoid
intentionally writing across neighboring array fields.

Validate the expected key size and introduce a wrapping structure
to use as the multi-field memcpy() destination so that overflows
can be correctly detected.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210616203952.1248910-1-keescook@chromium.org

diff --git a/drivers/net/wireless/intersil/orinoco/hw.c b/drivers/net/wireless/intersil/orinoco/hw.c
index 2c7adb4be10035500cb854f085e8d1c72169ffd2..0aea35c9c11c7a09be92e1a29e582c1baaa312c5 100644 (file)
--- a/drivers/net/wireless/intersil/orinoco/hw.c
+++ b/drivers/net/wireless/intersil/orinoco/hw.c
@@ -988,15 +988,18 @@ int __orinoco_hw_setup_enc(struct orinoco_private *priv)
  * tsc must be NULL or up to 8 bytes
  */
 int __orinoco_hw_set_tkip_key(struct orinoco_private *priv, int key_idx,
-                             int set_tx, const u8 *key, const u8 *rsc,
-                             size_t rsc_len, const u8 *tsc, size_t tsc_len)
+                             int set_tx, const u8 *key, size_t key_len,
+                             const u8 *rsc, size_t rsc_len,
+                             const u8 *tsc, size_t tsc_len)
 {
        struct {
                __le16 idx;
                u8 rsc[ORINOCO_SEQ_LEN];
-               u8 key[TKIP_KEYLEN];
-               u8 tx_mic[MIC_KEYLEN];
-               u8 rx_mic[MIC_KEYLEN];
+               struct {
+                       u8 key[TKIP_KEYLEN];
+                       u8 tx_mic[MIC_KEYLEN];
+                       u8 rx_mic[MIC_KEYLEN];
+               } tkip;
                u8 tsc[ORINOCO_SEQ_LEN];
        } __packed buf;
        struct hermes *hw = &priv->hw;
@@ -1011,8 +1014,9 @@ int __orinoco_hw_set_tkip_key(struct orinoco_private *priv, int key_idx,
                key_idx |= 0x8000;
 
        buf.idx = cpu_to_le16(key_idx);
-       memcpy(buf.key, key,
-              sizeof(buf.key) + sizeof(buf.tx_mic) + sizeof(buf.rx_mic));
+       if (key_len != sizeof(buf.tkip))
+               return -EINVAL;
+       memcpy(&buf.tkip, key, sizeof(buf.tkip));
 
        if (rsc_len > sizeof(buf.rsc))
                rsc_len = sizeof(buf.rsc);

diff --git a/drivers/net/wireless/intersil/orinoco/hw.h b/drivers/net/wireless/intersil/orinoco/hw.h
index 466d1ede76f16ee5436b680631e77047af2798af..da5804dbdf34c0965b4efefaf288a848561a3093 100644 (file)
--- a/drivers/net/wireless/intersil/orinoco/hw.h
+++ b/drivers/net/wireless/intersil/orinoco/hw.h
@@ -38,8 +38,9 @@ int __orinoco_hw_set_wap(struct orinoco_private *priv);
 int __orinoco_hw_setup_wepkeys(struct orinoco_private *priv);
 int __orinoco_hw_setup_enc(struct orinoco_private *priv);
 int __orinoco_hw_set_tkip_key(struct orinoco_private *priv, int key_idx,
-                             int set_tx, const u8 *key, const u8 *rsc,
-                             size_t rsc_len, const u8 *tsc, size_t tsc_len);
+                             int set_tx, const u8 *key, size_t key_len,
+                             const u8 *rsc, size_t rsc_len,
+                             const u8 *tsc, size_t tsc_len);
 int orinoco_clear_tkip_key(struct orinoco_private *priv, int key_idx);
 int __orinoco_hw_set_multicast_list(struct orinoco_private *priv,
                                    struct net_device *dev,

diff --git a/drivers/net/wireless/intersil/orinoco/wext.c b/drivers/net/wireless/intersil/orinoco/wext.c
index 7b6c4ae8ddb35dc3f4b84189edbb503547c4f7a8..4a01260027bc59bc0e5ca68e66a2088ce6570ccb 100644 (file)
--- a/drivers/net/wireless/intersil/orinoco/wext.c
+++ b/drivers/net/wireless/intersil/orinoco/wext.c
@@ -791,7 +791,7 @@ static int orinoco_ioctl_set_encodeext(struct net_device *dev,
 
                        err = __orinoco_hw_set_tkip_key(priv, idx,
                                 ext->ext_flags & IW_ENCODE_EXT_SET_TX_KEY,
-                                priv->keys[idx].key,
+                                priv->keys[idx].key, priv->keys[idx].key_len,
                                 tkip_iv, ORINOCO_SEQ_LEN, NULL, 0);
                        if (err)
                                printk(KERN_ERR "%s: Error %d setting TKIP key"