diff options
| author | Edward Adam Davis <eadavis@qq.com> | 2025-11-16 17:04:43 +0800 |
|---|---|---|
| committer | Luiz Augusto von Dentz <luiz.von.dentz@intel.com> | 2025-11-20 17:00:46 -0500 |
| commit | 89bb613511cc21ed5ba6bddc1c9b9ae9c0dad392 (patch) | |
| tree | 7f9244f3ded96ac83cc54c3e37865e7b8e61a024 /net/bluetooth | |
| parent | 275ddfeb3fdc274050c2173ffd985b1e80a9aa37 (diff) | |
Bluetooth: hci_sock: Prevent race in socket write iter and sock bind
There is a potential race condition between sock bind and socket write
iter. bind may free the same cmd via mgmt_pending before write iter sends
the cmd, just as syzbot reported in UAF[1].
Here we use hci_dev_lock to synchronize the two, thereby avoiding the
UAF mentioned in [1].
[1]
syzbot reported:
BUG: KASAN: slab-use-after-free in mgmt_pending_remove+0x3b/0x210 net/bluetooth/mgmt_util.c:316
Read of size 8 at addr ffff888077164818 by task syz.0.17/5989
Call Trace:
mgmt_pending_remove+0x3b/0x210 net/bluetooth/mgmt_util.c:316
set_link_security+0x5c2/0x710 net/bluetooth/mgmt.c:1918
hci_mgmt_cmd+0x9c9/0xef0 net/bluetooth/hci_sock.c:1719
hci_sock_sendmsg+0x6ca/0xef0 net/bluetooth/hci_sock.c:1839
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:742
sock_write_iter+0x279/0x360 net/socket.c:1195
Allocated by task 5989:
mgmt_pending_add+0x35/0x140 net/bluetooth/mgmt_util.c:296
set_link_security+0x557/0x710 net/bluetooth/mgmt.c:1910
hci_mgmt_cmd+0x9c9/0xef0 net/bluetooth/hci_sock.c:1719
hci_sock_sendmsg+0x6ca/0xef0 net/bluetooth/hci_sock.c:1839
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:742
sock_write_iter+0x279/0x360 net/socket.c:1195
Freed by task 5991:
mgmt_pending_free net/bluetooth/mgmt_util.c:311 [inline]
mgmt_pending_foreach+0x30d/0x380 net/bluetooth/mgmt_util.c:257
mgmt_index_removed+0x112/0x2f0 net/bluetooth/mgmt.c:9477
hci_sock_bind+0xbe9/0x1000 net/bluetooth/hci_sock.c:1314
Fixes: 6fe26f694c82 ("Bluetooth: MGMT: Protect mgmt_pending list with its own lock")
Reported-by: syzbot+9aa47cd4633a3cf92a80@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=9aa47cd4633a3cf92a80
Tested-by: syzbot+9aa47cd4633a3cf92a80@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Diffstat (limited to 'net/bluetooth')
| -rw-r--r-- | net/bluetooth/hci_sock.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/net/bluetooth/hci_sock.c b/net/bluetooth/hci_sock.c index fc866759910d..ad19022ae127 100644 --- a/net/bluetooth/hci_sock.c +++ b/net/bluetooth/hci_sock.c @@ -1311,7 +1311,9 @@ static int hci_sock_bind(struct socket *sock, struct sockaddr *addr, goto done; } + hci_dev_lock(hdev); mgmt_index_removed(hdev); + hci_dev_unlock(hdev); err = hci_dev_open(hdev->id); if (err) { |
