Syzbot reported an invalid-free that I introduced fixing a memleak.
bcsp_recv() also frees bcsp->rx_skb but never nullifies its value.
Nullify bcsp->rx_skb every time it is freed.
Signed-off-by: Tomas Bortoli <tomasbortoli@xxxxxxxxx>
Reported-by: syzbot+a0d209a4676664613e76@xxxxxxxxxxxxxxxxxxxxxxxxx
---
drivers/bluetooth/hci_bcsp.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/bluetooth/hci_bcsp.c b/drivers/bluetooth/hci_bcsp.c
index fe2e307009f4..cf4a56095817 100644
--- a/drivers/bluetooth/hci_bcsp.c
+++ b/drivers/bluetooth/hci_bcsp.c
@@ -591,6 +591,7 @@ static int bcsp_recv(struct hci_uart *hu, const void *data, int count)
if (*ptr == 0xc0) {
BT_ERR("Short BCSP packet");
kfree_skb(bcsp->rx_skb);
+ bcsp->rx_skb = NULL;
bcsp->rx_state = BCSP_W4_PKT_START;
bcsp->rx_count = 0;
} else
@@ -606,6 +607,7 @@ static int bcsp_recv(struct hci_uart *hu, const void *data, int count)
bcsp->rx_skb->data[2])) != bcsp->rx_skb->data[3]) {
BT_ERR("Error in BCSP hdr checksum");
kfree_skb(bcsp->rx_skb);
+ bcsp->rx_skb = NULL;
bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
bcsp->rx_count = 0;
continue;
@@ -630,6 +632,7 @@ static int bcsp_recv(struct hci_uart *hu, const void *data, int count)
bscp_get_crc(bcsp));
kfree_skb(bcsp->rx_skb);
+ bcsp->rx_skb = NULL;
bcsp->rx_state = BCSP_W4_PKT_DELIMITER;
bcsp->rx_count = 0;
continue;
--
2.20.1
