From 51eda36d33e43201e7a4fd35232e069b2c850b01 Mon Sep 17 00:00:00 2001 From: Luiz Augusto von Dentz Date: Fri, 5 Apr 2024 15:41:52 -0400 Subject: Bluetooth: SCO: Fix not validating setsockopt user input syzbot reported sco_sock_setsockopt() is copying data without checking user input length. BUG: KASAN: slab-out-of-bounds in copy_from_sockptr_offset include/linux/sockptr.h:49 [inline] BUG: KASAN: slab-out-of-bounds in copy_from_sockptr include/linux/sockptr.h:55 [inline] BUG: KASAN: slab-out-of-bounds in sco_sock_setsockopt+0xc0b/0xf90 net/bluetooth/sco.c:893 Read of size 4 at addr ffff88805f7b15a3 by task syz-executor.5/12578 Fixes: ad10b1a48754 ("Bluetooth: Add Bluetooth socket voice option") Fixes: b96e9c671b05 ("Bluetooth: Add BT_DEFER_SETUP option to sco socket") Fixes: 00398e1d5183 ("Bluetooth: Add support for BT_PKT_STATUS CMSG data for SCO connections") Fixes: f6873401a608 ("Bluetooth: Allow setting of codec for HFP offload use case") Reported-by: syzbot Signed-off-by: Eric Dumazet Signed-off-by: Luiz Augusto von Dentz --- include/net/bluetooth/bluetooth.h | 9 +++++++++ net/bluetooth/sco.c | 23 ++++++++++------------- 2 files changed, 19 insertions(+), 13 deletions(-) diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h index 9fe95a22abeb7..eaec5d6caa29d 100644 --- a/include/net/bluetooth/bluetooth.h +++ b/include/net/bluetooth/bluetooth.h @@ -585,6 +585,15 @@ static inline struct sk_buff *bt_skb_sendmmsg(struct sock *sk, return skb; } +static inline int bt_copy_from_sockptr(void *dst, size_t dst_size, + sockptr_t src, size_t src_size) +{ + if (dst_size > src_size) + return -EINVAL; + + return copy_from_sockptr(dst, src, dst_size); +} + int bt_to_errno(u16 code); __u8 bt_status(int err); diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c index 43daf965a01e4..368e026f4d15c 100644 --- a/net/bluetooth/sco.c +++ b/net/bluetooth/sco.c @@ -824,7 +824,7 @@ static int sco_sock_setsockopt(struct socket *sock, int level, int optname, sockptr_t optval, unsigned int optlen) { struct sock *sk = sock->sk; - int len, err = 0; + int err = 0; struct bt_voice voice; u32 opt; struct bt_codecs *codecs; @@ -843,10 +843,9 @@ static int sco_sock_setsockopt(struct socket *sock, int level, int optname, break; } - if (copy_from_sockptr(&opt, optval, sizeof(u32))) { - err = -EFAULT; + err = bt_copy_from_sockptr(&opt, sizeof(opt), optval, optlen); + if (err) break; - } if (opt) set_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags); @@ -863,11 +862,10 @@ static int sco_sock_setsockopt(struct socket *sock, int level, int optname, voice.setting = sco_pi(sk)->setting; - len = min_t(unsigned int, sizeof(voice), optlen); - if (copy_from_sockptr(&voice, optval, len)) { - err = -EFAULT; + err = bt_copy_from_sockptr(&voice, sizeof(voice), optval, + optlen); + if (err) break; - } /* Explicitly check for these values */ if (voice.setting != BT_VOICE_TRANSPARENT && @@ -890,10 +888,9 @@ static int sco_sock_setsockopt(struct socket *sock, int level, int optname, break; case BT_PKT_STATUS: - if (copy_from_sockptr(&opt, optval, sizeof(u32))) { - err = -EFAULT; + err = bt_copy_from_sockptr(&opt, sizeof(opt), optval, optlen); + if (err) break; - } if (opt) set_bit(BT_SK_PKT_STATUS, &bt_sk(sk)->flags); @@ -934,9 +931,9 @@ static int sco_sock_setsockopt(struct socket *sock, int level, int optname, break; } - if (copy_from_sockptr(buffer, optval, optlen)) { + err = bt_copy_from_sockptr(buffer, optlen, optval, optlen); + if (err) { hci_dev_put(hdev); - err = -EFAULT; break; } -- cgit 1.2.3-korg