From: Siddh Raman Pant <code@xxxxxxxx> [ Upstream commit b4066eb04bb67e7ff66e5aaab0db4a753f37eaad ] hci_connect_sco currently returns NULL when there is no link (i.e. when hci_conn_link() returns NULL). sco_connect() expects an ERR_PTR in case of any error (see line 266 in sco.c). Thus, hcon set as NULL passes through to sco_conn_add(), which tries to get hcon->hdev, resulting in dereferencing a NULL pointer as reported by syzkaller. The same issue exists for iso_connect_cis() calling hci_connect_cis(). Thus, make hci_connect_sco() and hci_connect_cis() return ERR_PTR instead of NULL. Reported-and-tested-by: syzbot+37acd5d80d00d609d233@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=37acd5d80d00d609d233 Fixes: 06149746e720 ("Bluetooth: hci_conn: Add support for linking multiple hcon") Signed-off-by: Siddh Raman Pant <code@xxxxxxxx> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/bluetooth/hci_conn.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c index 7b0c74ef93296..31c115b225e7e 100644 --- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c @@ -1684,7 +1684,7 @@ struct hci_conn *hci_connect_sco(struct hci_dev *hdev, int type, bdaddr_t *dst, if (!link) { hci_conn_drop(acl); hci_conn_drop(sco); - return NULL; + return ERR_PTR(-ENOLINK); } sco->setting = setting; @@ -2256,7 +2256,7 @@ struct hci_conn *hci_connect_cis(struct hci_dev *hdev, bdaddr_t *dst, if (!link) { hci_conn_drop(le); hci_conn_drop(cis); - return NULL; + return ERR_PTR(-ENOLINK); } /* If LE is already connected and CIS handle is already set proceed to -- 2.39.2
