From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Eric Dumazet <edumazet@google.com>,
James Chapman <jchapman@katalix.com>,
Andrii Nakryiko <andriin@fb.com>,
syzbot+3610d489778b57cc8031@syzkaller.appspotmail.com
Subject: [PATCH 4.19 03/25] l2tp: do not use inet_hash()/inet_unhash()
Date: Tue, 9 Jun 2020 19:44:53 +0200 [thread overview]
Message-ID: <20200609174048.979812603@linuxfoundation.org> (raw)
In-Reply-To: <20200609174048.576094775@linuxfoundation.org>
From: Eric Dumazet <edumazet@google.com>
[ Upstream commit 02c71b144c811bcdd865e0a1226d0407d11357e8 ]
syzbot recently found a way to crash the kernel [1]
Issue here is that inet_hash() & inet_unhash() are currently
only meant to be used by TCP & DCCP, since only these protocols
provide the needed hashinfo pointer.
L2TP uses a single list (instead of a hash table)
This old bug became an issue after commit 610236587600
("bpf: Add new cgroup attach type to enable sock modifications")
since after this commit, sk_common_release() can be called
while the L2TP socket is still considered 'hashed'.
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 7063 Comm: syz-executor654 Not tainted 5.7.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:inet_unhash+0x11f/0x770 net/ipv4/inet_hashtables.c:600
Code: 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e dd 04 00 00 48 8d 7d 08 44 8b 73 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 55 05 00 00 48 8d 7d 14 4c 8b 6d 08 48 b8 00 00
RSP: 0018:ffffc90001777d30 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff88809a6df940 RCX: ffffffff8697c242
RDX: 0000000000000001 RSI: ffffffff8697c251 RDI: 0000000000000008
RBP: 0000000000000000 R08: ffff88809f3ae1c0 R09: fffffbfff1514cc1
R10: ffffffff8a8a6607 R11: fffffbfff1514cc0 R12: ffff88809a6df9b0
R13: 0000000000000007 R14: 0000000000000000 R15: ffffffff873a4d00
FS: 0000000001d2b880(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000006cd090 CR3: 000000009403a000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
sk_common_release+0xba/0x370 net/core/sock.c:3210
inet_create net/ipv4/af_inet.c:390 [inline]
inet_create+0x966/0xe00 net/ipv4/af_inet.c:248
__sock_create+0x3cb/0x730 net/socket.c:1428
sock_create net/socket.c:1479 [inline]
__sys_socket+0xef/0x200 net/socket.c:1521
__do_sys_socket net/socket.c:1530 [inline]
__se_sys_socket net/socket.c:1528 [inline]
__x64_sys_socket+0x6f/0xb0 net/socket.c:1528
do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x441e29
Code: e8 fc b3 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdce184148 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000441e29
RDX: 0000000000000073 RSI: 0000000000000002 RDI: 0000000000000002
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000402c30 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace 23b6578228ce553e ]---
RIP: 0010:inet_unhash+0x11f/0x770 net/ipv4/inet_hashtables.c:600
Code: 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e dd 04 00 00 48 8d 7d 08 44 8b 73 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 55 05 00 00 48 8d 7d 14 4c 8b 6d 08 48 b8 00 00
RSP: 0018:ffffc90001777d30 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff88809a6df940 RCX: ffffffff8697c242
RDX: 0000000000000001 RSI: ffffffff8697c251 RDI: 0000000000000008
RBP: 0000000000000000 R08: ffff88809f3ae1c0 R09: fffffbfff1514cc1
R10: ffffffff8a8a6607 R11: fffffbfff1514cc0 R12: ffff88809a6df9b0
R13: 0000000000000007 R14: 0000000000000000 R15: ffffffff873a4d00
FS: 0000000001d2b880(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000006cd090 CR3: 000000009403a000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Fixes: 0d76751fad77 ("l2tp: Add L2TPv3 IP encapsulation (no UDP) support")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: James Chapman <jchapman@katalix.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Reported-by: syzbot+3610d489778b57cc8031@syzkaller.appspotmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/l2tp/l2tp_ip.c | 29 ++++++++++++++++++++++-------
net/l2tp/l2tp_ip6.c | 30 ++++++++++++++++++++++--------
2 files changed, 44 insertions(+), 15 deletions(-)
--- a/net/l2tp/l2tp_ip.c
+++ b/net/l2tp/l2tp_ip.c
@@ -24,7 +24,6 @@
#include <net/icmp.h>
#include <net/udp.h>
#include <net/inet_common.h>
-#include <net/inet_hashtables.h>
#include <net/tcp_states.h>
#include <net/protocol.h>
#include <net/xfrm.h>
@@ -213,15 +212,31 @@ discard:
return 0;
}
-static int l2tp_ip_open(struct sock *sk)
+static int l2tp_ip_hash(struct sock *sk)
{
- /* Prevent autobind. We don't have ports. */
- inet_sk(sk)->inet_num = IPPROTO_L2TP;
+ if (sk_unhashed(sk)) {
+ write_lock_bh(&l2tp_ip_lock);
+ sk_add_node(sk, &l2tp_ip_table);
+ write_unlock_bh(&l2tp_ip_lock);
+ }
+ return 0;
+}
+static void l2tp_ip_unhash(struct sock *sk)
+{
+ if (sk_unhashed(sk))
+ return;
write_lock_bh(&l2tp_ip_lock);
- sk_add_node(sk, &l2tp_ip_table);
+ sk_del_node_init(sk);
write_unlock_bh(&l2tp_ip_lock);
+}
+
+static int l2tp_ip_open(struct sock *sk)
+{
+ /* Prevent autobind. We don't have ports. */
+ inet_sk(sk)->inet_num = IPPROTO_L2TP;
+ l2tp_ip_hash(sk);
return 0;
}
@@ -598,8 +613,8 @@ static struct proto l2tp_ip_prot = {
.sendmsg = l2tp_ip_sendmsg,
.recvmsg = l2tp_ip_recvmsg,
.backlog_rcv = l2tp_ip_backlog_recv,
- .hash = inet_hash,
- .unhash = inet_unhash,
+ .hash = l2tp_ip_hash,
+ .unhash = l2tp_ip_unhash,
.obj_size = sizeof(struct l2tp_ip_sock),
#ifdef CONFIG_COMPAT
.compat_setsockopt = compat_ip_setsockopt,
--- a/net/l2tp/l2tp_ip6.c
+++ b/net/l2tp/l2tp_ip6.c
@@ -24,8 +24,6 @@
#include <net/icmp.h>
#include <net/udp.h>
#include <net/inet_common.h>
-#include <net/inet_hashtables.h>
-#include <net/inet6_hashtables.h>
#include <net/tcp_states.h>
#include <net/protocol.h>
#include <net/xfrm.h>
@@ -226,15 +224,31 @@ discard:
return 0;
}
-static int l2tp_ip6_open(struct sock *sk)
+static int l2tp_ip6_hash(struct sock *sk)
{
- /* Prevent autobind. We don't have ports. */
- inet_sk(sk)->inet_num = IPPROTO_L2TP;
+ if (sk_unhashed(sk)) {
+ write_lock_bh(&l2tp_ip6_lock);
+ sk_add_node(sk, &l2tp_ip6_table);
+ write_unlock_bh(&l2tp_ip6_lock);
+ }
+ return 0;
+}
+static void l2tp_ip6_unhash(struct sock *sk)
+{
+ if (sk_unhashed(sk))
+ return;
write_lock_bh(&l2tp_ip6_lock);
- sk_add_node(sk, &l2tp_ip6_table);
+ sk_del_node_init(sk);
write_unlock_bh(&l2tp_ip6_lock);
+}
+
+static int l2tp_ip6_open(struct sock *sk)
+{
+ /* Prevent autobind. We don't have ports. */
+ inet_sk(sk)->inet_num = IPPROTO_L2TP;
+ l2tp_ip6_hash(sk);
return 0;
}
@@ -732,8 +746,8 @@ static struct proto l2tp_ip6_prot = {
.sendmsg = l2tp_ip6_sendmsg,
.recvmsg = l2tp_ip6_recvmsg,
.backlog_rcv = l2tp_ip6_backlog_recv,
- .hash = inet6_hash,
- .unhash = inet_unhash,
+ .hash = l2tp_ip6_hash,
+ .unhash = l2tp_ip6_unhash,
.obj_size = sizeof(struct l2tp_ip6_sock),
#ifdef CONFIG_COMPAT
.compat_setsockopt = compat_ipv6_setsockopt,
next prev parent reply other threads:[~2020-06-09 18:13 UTC|newest]
Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-09 17:44 [PATCH 4.19 00/25] 4.19.128-rc1 review Greg Kroah-Hartman
2020-06-09 17:44 ` [PATCH 4.19 01/25] devinet: fix memleak in inetdev_init() Greg Kroah-Hartman
2020-06-09 17:44 ` [PATCH 4.19 02/25] l2tp: add sk_family checks to l2tp_validate_socket Greg Kroah-Hartman
2020-06-09 17:44 ` Greg Kroah-Hartman [this message]
2020-06-09 17:44 ` [PATCH 4.19 04/25] net: usb: qmi_wwan: add Telit LE910C1-EUX composition Greg Kroah-Hartman
2020-06-09 17:44 ` [PATCH 4.19 05/25] NFC: st21nfca: add missed kfree_skb() in an error path Greg Kroah-Hartman
2020-06-09 17:44 ` [PATCH 4.19 06/25] vsock: fix timeout in vsock_accept() Greg Kroah-Hartman
2020-06-09 17:44 ` [PATCH 4.19 07/25] net: check untrusted gso_size at kernel entry Greg Kroah-Hartman
2020-06-09 17:44 ` [PATCH 4.19 08/25] USB: serial: qcserial: add DW5816e QDL support Greg Kroah-Hartman
2020-06-09 17:44 ` [PATCH 4.19 09/25] USB: serial: usb_wwan: do not resubmit rx urb on fatal errors Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 10/25] USB: serial: option: add Telit LE910C1-EUX compositions Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 11/25] iio: vcnl4000: Fix i2c swapped word reading Greg Kroah-Hartman
2020-06-15 13:30 ` Pavel Machek
2020-06-16 8:18 ` Jonathan Cameron
2020-06-09 17:45 ` [PATCH 4.19 12/25] usb: musb: start session in resume for host port Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 13/25] usb: musb: Fix runtime PM imbalance on error Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 14/25] vt: keyboard: avoid signed integer overflow in k_ascii Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 15/25] tty: hvc_console, fix crashes on parallel open/close Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 16/25] staging: rtl8712: Fix IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 17/25] CDC-ACM: heed quirk also in error handling Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 18/25] nvmem: qfprom: remove incorrect write support Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 19/25] x86/cpu: Add a steppings field to struct x86_cpu_id Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 20/25] x86/cpu: Add table argument to cpu_matches() Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 21/25] x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigation Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 22/25] x86/speculation: Add SRBDS vulnerability and mitigation documentation Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 23/25] x86/speculation: Add Ivy Bridge to affected list Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 24/25] uprobes: ensure that uprobe->offset and ->ref_ctr_offset are properly aligned Greg Kroah-Hartman
2020-06-09 18:55 ` Naresh Kamboju
2020-06-09 19:03 ` Greg Kroah-Hartman
2020-06-10 14:53 ` Oleg Nesterov
2020-06-10 14:58 ` Greg Kroah-Hartman
2020-06-11 16:51 ` Oleg Nesterov
2020-06-12 5:46 ` Greg Kroah-Hartman
2020-06-09 17:45 ` [PATCH 4.19 25/25] Revert "net/mlx5: Annotate mutex destroy for root ns" Greg Kroah-Hartman
2020-06-11 22:17 ` Saeed Mahameed
2020-06-12 1:07 ` Sasha Levin
2020-06-09 19:01 ` [PATCH 4.19 00/25] 4.19.128-rc1 review Naresh Kamboju
2020-06-09 19:20 ` Shuah Khan
2020-06-09 19:41 ` Greg Kroah-Hartman
2020-06-10 11:29 ` Jon Hunter
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