From: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com> mainline inclusion from mainline-v5.16-rc1 commit f4712fa993f688d0a48e0c28728fcdeb88c1ea58 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IB2BXB CVE: CVE-2024-50125 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- In sco_conn_del, conn->sk is read while holding on to the sco_conn.lock to avoid races with a socket that could be released concurrently. However, in between unlocking sco_conn.lock and calling sock_hold, it's possible for the socket to be freed, which would cause a use-after-free write when sock_hold is finally called. To fix this, the reference count of the socket should be increased while the sco_conn.lock is still held. Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Dong Chenchen <dongchenchen2@huawei.com> --- net/bluetooth/sco.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c index 2083c0552857..28b69bc6d52c 100644 --- a/net/bluetooth/sco.c +++ b/net/bluetooth/sco.c @@ -193,10 +193,11 @@ static void sco_conn_del(struct hci_conn *hcon, int err) /* Kill socket */ sco_conn_lock(conn); sk = conn->sk; + if (sk) + sock_hold(sk); sco_conn_unlock(conn); if (sk) { - sock_hold(sk); lock_sock(sk); sco_sock_clear_timer(sk); sco_chan_del(sk, err); -- 2.25.1