linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	stable@vger.kernel.org, Or Cohen <orcohen@paloaltonetworks.com>,
	Xin Long <lucien.xin@gmail.com>,
	Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>,
	"David S. Miller" <davem@davemloft.net>
Subject: [PATCH 4.14 01/49] net/sctp: fix race condition in sctp_destroy_sock
Date: Mon, 26 Apr 2021 09:28:57 +0200	[thread overview]
Message-ID: <20210426072819.769758434@linuxfoundation.org> (raw)
In-Reply-To: <20210426072819.721586742@linuxfoundation.org>

From: Or Cohen <orcohen@paloaltonetworks.com>

commit b166a20b07382b8bc1dcee2a448715c9c2c81b5b upstream.

If sctp_destroy_sock is called without sock_net(sk)->sctp.addr_wq_lock
held and sp->do_auto_asconf is true, then an element is removed
from the auto_asconf_splist without any proper locking.

This can happen in the following functions:
1. In sctp_accept, if sctp_sock_migrate fails.
2. In inet_create or inet6_create, if there is a bpf program
   attached to BPF_CGROUP_INET_SOCK_CREATE which denies
   creation of the sctp socket.

The bug is fixed by acquiring addr_wq_lock in sctp_destroy_sock
instead of sctp_close.

This addresses CVE-2021-23133.

Reported-by: Or Cohen <orcohen@paloaltonetworks.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Fixes: 610236587600 ("bpf: Add new cgroup attach type to enable sock modifications")
Signed-off-by: Or Cohen <orcohen@paloaltonetworks.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/sctp/socket.c |   13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1586,11 +1586,9 @@ static void sctp_close(struct sock *sk,
 
 	/* Supposedly, no process has access to the socket, but
 	 * the net layers still may.
-	 * Also, sctp_destroy_sock() needs to be called with addr_wq_lock
-	 * held and that should be grabbed before socket lock.
 	 */
-	spin_lock_bh(&net->sctp.addr_wq_lock);
-	bh_lock_sock_nested(sk);
+	local_bh_disable();
+	bh_lock_sock(sk);
 
 	/* Hold the sock, since sk_common_release() will put sock_put()
 	 * and we have just a little more cleanup.
@@ -1599,7 +1597,7 @@ static void sctp_close(struct sock *sk,
 	sk_common_release(sk);
 
 	bh_unlock_sock(sk);
-	spin_unlock_bh(&net->sctp.addr_wq_lock);
+	local_bh_enable();
 
 	sock_put(sk);
 
@@ -4449,9 +4447,6 @@ static int sctp_init_sock(struct sock *s
 	sk_sockets_allocated_inc(sk);
 	sock_prot_inuse_add(net, sk->sk_prot, 1);
 
-	/* Nothing can fail after this block, otherwise
-	 * sctp_destroy_sock() will be called without addr_wq_lock held
-	 */
 	if (net->sctp.default_auto_asconf) {
 		spin_lock(&sock_net(sk)->sctp.addr_wq_lock);
 		list_add_tail(&sp->auto_asconf_list,
@@ -4486,7 +4481,9 @@ static void sctp_destroy_sock(struct soc
 
 	if (sp->do_auto_asconf) {
 		sp->do_auto_asconf = 0;
+		spin_lock_bh(&sock_net(sk)->sctp.addr_wq_lock);
 		list_del(&sp->auto_asconf_list);
+		spin_unlock_bh(&sock_net(sk)->sctp.addr_wq_lock);
 	}
 	sctp_endpoint_free(sp->ep);
 	local_bh_disable();



  reply	other threads:[~2021-04-26  7:36 UTC|newest]

Thread overview: 53+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-26  7:28 [PATCH 4.14 00/49] 4.14.232-rc1 review Greg Kroah-Hartman
2021-04-26  7:28 ` Greg Kroah-Hartman [this message]
2021-04-26  7:28 ` [PATCH 4.14 02/49] Input: nspire-keypad - enable interrupts only when opened Greg Kroah-Hartman
2021-04-26  7:28 ` [PATCH 4.14 03/49] dmaengine: dw: Make it dependent to HAS_IOMEM Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 04/49] ARM: dts: Fix moving mmc devices with aliases for omap4 & 5 Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 05/49] arc: kernel: Return -EFAULT if copy_to_user() fails Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 06/49] neighbour: Disregard DEAD dst in neigh_update Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 07/49] ARM: keystone: fix integer overflow warning Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 08/49] ASoC: fsl_esai: Fix TDM slot setup for I2S mode Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 09/49] scsi: scsi_transport_srp: Dont block target in SRP_PORT_LOST state Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 10/49] net: ieee802154: stop dump llsec keys for monitors Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 11/49] net: ieee802154: stop dump llsec devs " Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 12/49] net: ieee802154: forbid monitor for add llsec dev Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 13/49] net: ieee802154: stop dump llsec devkeys for monitors Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 14/49] net: ieee802154: forbid monitor for add llsec devkey Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 15/49] net: ieee802154: stop dump llsec seclevels for monitors Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 16/49] net: ieee802154: forbid monitor for add llsec seclevel Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 17/49] pcnet32: Use pci_resource_len to validate PCI resource Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 18/49] usbip: Fix incorrect double assignment to udc->ud.tcp_rx Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 19/49] mac80211: clear sta->fast_rx when STA removed from 4-addr VLAN Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 20/49] Input: i8042 - fix Pegatron C15B ID entry Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 21/49] HID: wacom: set EV_KEY and EV_ABS only for non-HID_GENERIC type of devices Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 22/49] readdir: make sure to verify directory entry for legacy interfaces too Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 23/49] arm64: fix inline asm in load_unaligned_zeropad() Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 24/49] arm64: alternatives: Move length validation in alternative_{insn, endif} Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 25/49] scsi: libsas: Reset num_scatter if libata marks qc as NODATA Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 26/49] netfilter: conntrack: do not print icmpv6 as unknown via /proc Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 27/49] netfilter: nft_limit: avoid possible divide error in nft_limit_init Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 28/49] net: davicom: Fix regulator not turned off on failed probe Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 29/49] net: sit: Unregister catch-all devices Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 30/49] i40e: fix the panic when running bpf in xdpdrv mode Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 31/49] ibmvnic: avoid calling napi_disable() twice Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 32/49] ibmvnic: remove duplicate napi_schedule call in do_reset function Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 33/49] ibmvnic: remove duplicate napi_schedule call in open function Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 34/49] ARM: footbridge: fix PCI interrupt mapping Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 35/49] ARM: 9071/1: uprobes: Dont hook on thumb instructions Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 36/49] gup: document and work around "COW can break either way" issue Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 37/49] net: hso: fix null-ptr-deref during tty device unregistration Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 38/49] ext4: correct error label in ext4_rename() Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 39/49] pinctrl: lewisburg: Update number of pins in community Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 40/49] HID: alps: fix error return code in alps_input_configured() Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 41/49] HID: wacom: Assign boolean values to a bool variable Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 42/49] ARM: dts: Fix swapped mmc order for omap3 Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 43/49] net: geneve: check skb is large enough for IPv4/IPv6 header Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 44/49] s390/entry: save the caller of psw_idle Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 45/49] xen-netback: Check for hotplug-status existence before watching Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 46/49] cavium/liquidio: Fix duplicate argument Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 47/49] ia64: fix discontig.c section mismatches Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 48/49] ia64: tools: remove duplicate definition of ia64_mf() on ia64 Greg Kroah-Hartman
2021-04-26  7:29 ` [PATCH 4.14 49/49] x86/crash: Fix crash_setup_memmap_entries() out-of-bounds access Greg Kroah-Hartman
2021-04-26 18:33 ` [PATCH 4.14 00/49] 4.14.232-rc1 review Guenter Roeck
2021-04-27  6:58 ` Naresh Kamboju
2021-04-27  9:26 ` Samuel Zou

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210426072819.769758434@linuxfoundation.org \
    --to=gregkh@linuxfoundation.org \
    --cc=davem@davemloft.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lucien.xin@gmail.com \
    --cc=marcelo.leitner@gmail.com \
    --cc=orcohen@paloaltonetworks.com \
    --cc=stable@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).