diff options
| -rw-r--r-- | libre/linux-libre/fix_race_condition_in_packet_set_ring.diff | 84 |
1 files changed, 0 insertions, 84 deletions
diff --git a/libre/linux-libre/fix_race_condition_in_packet_set_ring.diff b/libre/linux-libre/fix_race_condition_in_packet_set_ring.diff deleted file mode 100644 index 12048f611..000000000 --- a/libre/linux-libre/fix_race_condition_in_packet_set_ring.diff +++ /dev/null @@ -1,84 +0,0 @@ -From: Philip Pettersson <philip.pettersson@gmail.com> - -When packet_set_ring creates a ring buffer it will initialize a -struct timer_list if the packet version is TPACKET_V3. This value -can then be raced by a different thread calling setsockopt to -set the version to TPACKET_V1 before packet_set_ring has finished. - -This leads to a use-after-free on a function pointer in the -struct timer_list when the socket is closed as the previously -initialized timer will not be deleted. - -The bug is fixed by taking lock_sock(sk) in packet_setsockopt when -changing the packet version while also taking the lock at the start -of packet_set_ring. - -Fixes: f6fb8f100b80 ("af-packet: TPACKET_V3 flexible buffer implementation.") -Signed-off-by: Philip Pettersson <philip.pettersson@gmail.com> -Signed-off-by: Eric Dumazet <edumazet@google.com> ---- - net/packet/af_packet.c | 18 ++++++++++++------ - 1 file changed, 12 insertions(+), 6 deletions(-) - -diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c -index d2238b204691b8e4f2e3acb9bc167b553ba32d50..dd2332390c45bbff7c3fc5d259453f2e1ca352bf 100644 ---- a/net/packet/af_packet.c -+++ b/net/packet/af_packet.c -@@ -3648,19 +3648,25 @@ packet_setsockopt(struct socket *sock, int level, int optname, char __user *optv - - if (optlen != sizeof(val)) - return -EINVAL; -- if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) -- return -EBUSY; - if (copy_from_user(&val, optval, sizeof(val))) - return -EFAULT; - switch (val) { - case TPACKET_V1: - case TPACKET_V2: - case TPACKET_V3: -- po->tp_version = val; -- return 0; -+ break; - default: - return -EINVAL; - } -+ lock_sock(sk); -+ if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) { -+ ret = -EBUSY; -+ } else { -+ po->tp_version = val; -+ ret = 0; -+ } -+ release_sock(sk); -+ return ret; - } - case PACKET_RESERVE: - { -@@ -4164,6 +4170,7 @@ static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u, - /* Added to avoid minimal code churn */ - struct tpacket_req *req = &req_u->req; - -+ lock_sock(sk); - /* Opening a Tx-ring is NOT supported in TPACKET_V3 */ - if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) { - net_warn_ratelimited("Tx-ring is not supported.\n"); -@@ -4245,7 +4252,6 @@ static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u, - goto out; - } - -- lock_sock(sk); - - /* Detach socket from network */ - spin_lock(&po->bind_lock); -@@ -4294,11 +4300,11 @@ static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u, - if (!tx_ring) - prb_shutdown_retire_blk_timer(po, rb_queue); - } -- release_sock(sk); - - if (pg_vec) - free_pg_vec(pg_vec, order, req->tp_block_nr); - out: -+ release_sock(sk); - return err; - } |