linux-stable.git/net/sctp/socket.c, branch linux-5.17.y

sctp: Initialize daddr on peeled off socket

2022-04-20T07:36:16+00:00

[ Upstream commit 8467dda0c26583547731e7f3ea73fc3856bae3bf ]

Function sctp_do_peeloff() wrongly initializes daddr of the original
socket instead of the peeled off socket, which makes getpeername()
return zeroes instead of the primary address. Initialize the new socket
instead.

Fixes: d570ee490fb1 ("[SCTP]: Correctly set daddr for IPv6 sockets during peeloff")
Signed-off-by: Petr Malat 
Acked-by: Marcelo Ricardo Leitner 
Link: https://lore.kernel.org/r/20220409063611.673193-1-oss@malat.biz
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2022-01-05T22:36:10+00:00

No conflicts.

Signed-off-by: Jakub Kicinski

sctp: hold endpoint before calling cb in sctp_transport_lookup_process

2022-01-02T12:46:41+00:00

The same fix in commit 5ec7d18d1813 ("sctp: use call_rcu to free endpoint")
is also needed for dumping one asoc and sock after the lookup.

Fixes: 86fdb3448cc1 ("sctp: ensure ep is not destroyed before doing the dump")
Signed-off-by: Xin Long 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2021-12-30T20:12:12+00:00

drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
  commit 077cdda764c7 ("net/mlx5e: TC, Fix memory leak with rules with internal port")
  commit 31108d142f36 ("net/mlx5: Fix some error handling paths in 'mlx5e_tc_add_fdb_flow()'")
  commit 4390c6edc0fb ("net/mlx5: Fix some error handling paths in 'mlx5e_tc_add_fdb_flow()'")
  https://lore.kernel.org/all/20211229065352.30178-1-saeed@kernel.org/

net/smc/smc_wr.c
  commit 49dc9013e34b ("net/smc: Use the bitmap API when applicable")
  commit 349d43127dac ("net/smc: fix kernel panic caused by race of smc_sock")
  bitmap_zero()/memset() is removed by the fix

Signed-off-by: Jakub Kicinski

sctp: use call_rcu to free endpoint

2021-12-25T17:13:37+00:00

This patch is to delay the endpoint free by calling call_rcu() to fix
another use-after-free issue in sctp_sock_dump():

  BUG: KASAN: use-after-free in __lock_acquire+0x36d9/0x4c20
  Call Trace:
    __lock_acquire+0x36d9/0x4c20 kernel/locking/lockdep.c:3218
    lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844
    __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
    _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:168
    spin_lock_bh include/linux/spinlock.h:334 [inline]
    __lock_sock+0x203/0x350 net/core/sock.c:2253
    lock_sock_nested+0xfe/0x120 net/core/sock.c:2774
    lock_sock include/net/sock.h:1492 [inline]
    sctp_sock_dump+0x122/0xb20 net/sctp/diag.c:324
    sctp_for_each_transport+0x2b5/0x370 net/sctp/socket.c:5091
    sctp_diag_dump+0x3ac/0x660 net/sctp/diag.c:527
    __inet_diag_dump+0xa8/0x140 net/ipv4/inet_diag.c:1049
    inet_diag_dump+0x9b/0x110 net/ipv4/inet_diag.c:1065
    netlink_dump+0x606/0x1080 net/netlink/af_netlink.c:2244
    __netlink_dump_start+0x59a/0x7c0 net/netlink/af_netlink.c:2352
    netlink_dump_start include/linux/netlink.h:216 [inline]
    inet_diag_handler_cmd+0x2ce/0x3f0 net/ipv4/inet_diag.c:1170
    __sock_diag_cmd net/core/sock_diag.c:232 [inline]
    sock_diag_rcv_msg+0x31d/0x410 net/core/sock_diag.c:263
    netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2477
    sock_diag_rcv+0x2a/0x40 net/core/sock_diag.c:274

This issue occurs when asoc is peeled off and the old sk is freed after
getting it by asoc->base.sk and before calling lock_sock(sk).

To prevent the sk free, as a holder of the sk, ep should be alive when
calling lock_sock(). This patch uses call_rcu() and moves sock_put and
ep free into sctp_endpoint_destroy_rcu(), so that it's safe to try to
hold the ep under rcu_read_lock in sctp_transport_traverse_process().

If sctp_endpoint_hold() returns true, it means this ep is still alive
and we have held it and can continue to dump it; If it returns false,
it means this ep is dead and can be freed after rcu_read_unlock, and
we should skip it.

In sctp_sock_dump(), after locking the sk, if this ep is different from
tsp->asoc->ep, it means during this dumping, this asoc was peeled off
before calling lock_sock(), and the sk should be skipped; If this ep is
the same with tsp->asoc->ep, it means no peeloff happens on this asoc,
and due to lock_sock, no peeloff will happen either until release_sock.

Note that delaying endpoint free won't delay the port release, as the
port release happens in sctp_endpoint_destroy() before calling call_rcu().
Also, freeing endpoint by call_rcu() makes it safe to access the sk by
asoc->base.sk in sctp_assocs_seq_show() and sctp_rcv().

Thanks Jones to bring this issue up.

v1->v2:
  - improve the changelog.
  - add kfree(ep) into sctp_endpoint_destroy_rcu(), as Jakub noticed.

Reported-by: syzbot+9276d76e83e3bcde6c99@syzkaller.appspotmail.com
Reported-by: Lee Jones 
Fixes: d25adbeb0cdb ("sctp: fix an use-after-free issue in sctp_sock_dump")
Signed-off-by: Xin Long 
Signed-off-by: David S. Miller

sctp: move hlist_node and hashent out of sctp_ep_common

2021-12-23T11:15:30+00:00

Struct sctp_ep_common is included in both asoc and ep, but hlist_node
and hashent are only needed by ep after asoc_hashtable was dropped by
Commit b5eff7128366 ("sctp: drop the old assoc hashtable of sctp").

So it is better to move hlist_node and hashent from sctp_ep_common to
sctp_endpoint, and it saves some space for each asoc.

Signed-off-by: Xin Long 
Signed-off-by: David S. Miller

net: drop nopreempt requirement on sock_prot_inuse_add()

2021-11-16T13:20:45+00:00

This is distracting really, let's make this simpler,
because many callers had to take care of this
by themselves, even if on x86 this adds more
code than really needed.

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

security: pass asoc to sctp_assoc_request and sctp_sk_clone

2021-11-03T11:09:20+00:00

This patch is to move secid and peer_secid from endpoint to association,
and pass asoc to sctp_assoc_request and sctp_sk_clone instead of ep. As
ep is the local endpoint and asoc represents a connection, and in SCTP
one sk/ep could have multiple asoc/connection, saving secid/peer_secid
for new asoc will overwrite the old asoc's.

Note that since asoc can be passed as NULL, security_sctp_assoc_request()
is moved to the place right after the new_asoc is created in
sctp_sf_do_5_1B_init() and sctp_sf_do_unexpected_init().

v1->v2:
  - fix the description of selinux_netlbl_skbuff_setsid(), as Jakub noticed.
  - fix the annotation in selinux_sctp_assoc_request(), as Richard Noticed.

Fixes: 72e89f50084c ("security: Add support for SCTP security hooks")
Reported-by: Prashanth Prahlad 
Reviewed-by: Richard Haines 
Tested-by: Richard Haines 
Signed-off-by: Xin Long 
Signed-off-by: David S. Miller

sctp: trim optlen when it's a huge value in sctp_setsockopt

2021-07-18T16:47:29+00:00

After commit ca84bd058dae ("sctp: copy the optval from user space in
sctp_setsockopt"), it does memory allocation in sctp_setsockopt with
the optlen, and it would fail the allocation and return error if the
optlen from user space is a huge value.

This breaks some sockopts, like SCTP_HMAC_IDENT, SCTP_RESET_STREAMS and
SCTP_AUTH_KEY, as when processing these sockopts before, optlen would
be trimmed to a biggest value it needs when optlen is a huge value,
instead of failing the allocation and returning error.

This patch is to fix the allocation failure when it's a huge optlen from
user space by trimming it to the biggest size sctp sockopt may need when
necessary, and this biggest size is from sctp_setsockopt_reset_streams()
for SCTP_RESET_STREAMS, which is bigger than those for SCTP_HMAC_IDENT
and SCTP_AUTH_KEY.

Fixes: ca84bd058dae ("sctp: copy the optval from user space in sctp_setsockopt")
Signed-off-by: Xin Long 
Signed-off-by: David S. Miller

sctp: enable PLPMTUD when the transport is ready

2021-06-22T18:28:52+00:00

sctp_transport_pl_reset() is called whenever any of these 3 members in
transport is changed:

  - probe_interval
  - param_flags & SPP_PMTUD_ENABLE
  - state == ACTIVE

If all are true, start the PLPMTUD when it's not yet started. If any of
these is false, stop the PLPMTUD when it's already running.

sctp_transport_pl_update() is called when the transport dst has changed.
It will restart the PLPMTUD probe. Again, the pathmtu won't change but
use the dst's mtu until the Search phase is done.

Note that after using PLPMTUD, the pathmtu is only initialized with the
dst mtu when the transport dst changes. At other time it is updated by
pl.pmtu. So sctp_transport_pmtu_check() will be called only when PLPMTUD
is disabled in sctp_packet_config().

After this patch, the PLPMTUD feature from RFC8899 will be activated
and can be used by users.

Signed-off-by: Xin Long 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller