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-rw-r--r--fix_race_condition_in_packet_set_ring.diff85
1 files changed, 0 insertions, 85 deletions
diff --git a/fix_race_condition_in_packet_set_ring.diff b/fix_race_condition_in_packet_set_ring.diff
deleted file mode 100644
index 25e7ca8f505..00000000000
--- a/fix_race_condition_in_packet_set_ring.diff
+++ /dev/null
@@ -1,85 +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;
- }
-