linux-next/net/smc/smc_inet.c
D. Wythe 6fd27ea183 net/smc: fix lacks of icsk_syn_mss with IPPROTO_SMC
Eric report a panic on IPPROTO_SMC, and give the facts
that when INET_PROTOSW_ICSK was set, icsk->icsk_sync_mss must be set too.

Bug: Unable to handle kernel NULL pointer dereference at virtual address
0000000000000000
Mem abort info:
ESR = 0x0000000086000005
EC = 0x21: IABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x05: level 1 translation fault
user pgtable: 4k pages, 48-bit VAs, pgdp=00000001195d1000
[0000000000000000] pgd=0800000109c46003, p4d=0800000109c46003,
pud=0000000000000000
Internal error: Oops: 0000000086000005 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 UID: 0 PID: 8037 Comm: syz.3.265 Not tainted
6.11.0-rc7-syzkaller-g5f5673607153 #0
Hardware name: Google Google Compute Engine/Google Compute Engine,
BIOS Google 08/06/2024
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : 0x0
lr : cipso_v4_sock_setattr+0x2a8/0x3c0 net/ipv4/cipso_ipv4.c:1910
sp : ffff80009b887a90
x29: ffff80009b887aa0 x28: ffff80008db94050 x27: 0000000000000000
x26: 1fffe0001aa6f5b3 x25: dfff800000000000 x24: ffff0000db75da00
x23: 0000000000000000 x22: ffff0000d8b78518 x21: 0000000000000000
x20: ffff0000d537ad80 x19: ffff0000d8b78000 x18: 1fffe000366d79ee
x17: ffff8000800614a8 x16: ffff800080569b84 x15: 0000000000000001
x14: 000000008b336894 x13: 00000000cd96feaa x12: 0000000000000003
x11: 0000000000040000 x10: 00000000000020a3 x9 : 1fffe0001b16f0f1
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : 0000000000000001 x3 : 0000000000000000
x2 : 0000000000000002 x1 : 0000000000000000 x0 : ffff0000d8b78000
Call trace:
0x0
netlbl_sock_setattr+0x2e4/0x338 net/netlabel/netlabel_kapi.c:1000
smack_netlbl_add+0xa4/0x154 security/smack/smack_lsm.c:2593
smack_socket_post_create+0xa8/0x14c security/smack/smack_lsm.c:2973
security_socket_post_create+0x94/0xd4 security/security.c:4425
__sock_create+0x4c8/0x884 net/socket.c:1587
sock_create net/socket.c:1622 [inline]
__sys_socket_create net/socket.c:1659 [inline]
__sys_socket+0x134/0x340 net/socket.c:1706
__do_sys_socket net/socket.c:1720 [inline]
__se_sys_socket net/socket.c:1718 [inline]
__arm64_sys_socket+0x7c/0x94 net/socket.c:1718
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712
el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598
Code: ???????? ???????? ???????? ???????? (????????)
---[ end trace 0000000000000000 ]---

This patch add a toy implementation that performs a simple return to
prevent such panic. This is because MSS can be set in sock_create_kern
or smc_setsockopt, similar to how it's done in AF_SMC. However, for
AF_SMC, there is currently no way to synchronize MSS within
__sys_connect_file. This toy implementation lays the groundwork for us
to support such feature for IPPROTO_SMC in the future.

Fixes: d25a92ccae ("net/smc: Introduce IPPROTO_SMC")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Link: https://patch.msgid.link/1728456916-67035-1-git-send-email-alibuda@linux.alibaba.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-10 08:48:11 -07:00

177 lines
4.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Shared Memory Communications over RDMA (SMC-R) and RoCE
*
* Definitions for the IPPROTO_SMC (socket related)
*
* Copyright IBM Corp. 2016, 2018
* Copyright (c) 2024, Alibaba Inc.
*
* Author: D. Wythe <alibuda@linux.alibaba.com>
*/
#include <net/protocol.h>
#include <net/sock.h>
#include "smc_inet.h"
#include "smc.h"
static int smc_inet_init_sock(struct sock *sk);
static struct proto smc_inet_prot = {
.name = "INET_SMC",
.owner = THIS_MODULE,
.init = smc_inet_init_sock,
.hash = smc_hash_sk,
.unhash = smc_unhash_sk,
.release_cb = smc_release_cb,
.obj_size = sizeof(struct smc_sock),
.h.smc_hash = &smc_v4_hashinfo,
.slab_flags = SLAB_TYPESAFE_BY_RCU,
};
static const struct proto_ops smc_inet_stream_ops = {
.family = PF_INET,
.owner = THIS_MODULE,
.release = smc_release,
.bind = smc_bind,
.connect = smc_connect,
.socketpair = sock_no_socketpair,
.accept = smc_accept,
.getname = smc_getname,
.poll = smc_poll,
.ioctl = smc_ioctl,
.listen = smc_listen,
.shutdown = smc_shutdown,
.setsockopt = smc_setsockopt,
.getsockopt = smc_getsockopt,
.sendmsg = smc_sendmsg,
.recvmsg = smc_recvmsg,
.mmap = sock_no_mmap,
.splice_read = smc_splice_read,
};
static struct inet_protosw smc_inet_protosw = {
.type = SOCK_STREAM,
.protocol = IPPROTO_SMC,
.prot = &smc_inet_prot,
.ops = &smc_inet_stream_ops,
.flags = INET_PROTOSW_ICSK,
};
#if IS_ENABLED(CONFIG_IPV6)
struct smc6_sock {
struct smc_sock smc;
struct ipv6_pinfo inet6;
};
static struct proto smc_inet6_prot = {
.name = "INET6_SMC",
.owner = THIS_MODULE,
.init = smc_inet_init_sock,
.hash = smc_hash_sk,
.unhash = smc_unhash_sk,
.release_cb = smc_release_cb,
.obj_size = sizeof(struct smc6_sock),
.h.smc_hash = &smc_v6_hashinfo,
.slab_flags = SLAB_TYPESAFE_BY_RCU,
.ipv6_pinfo_offset = offsetof(struct smc6_sock, inet6),
};
static const struct proto_ops smc_inet6_stream_ops = {
.family = PF_INET6,
.owner = THIS_MODULE,
.release = smc_release,
.bind = smc_bind,
.connect = smc_connect,
.socketpair = sock_no_socketpair,
.accept = smc_accept,
.getname = smc_getname,
.poll = smc_poll,
.ioctl = smc_ioctl,
.listen = smc_listen,
.shutdown = smc_shutdown,
.setsockopt = smc_setsockopt,
.getsockopt = smc_getsockopt,
.sendmsg = smc_sendmsg,
.recvmsg = smc_recvmsg,
.mmap = sock_no_mmap,
.splice_read = smc_splice_read,
};
static struct inet_protosw smc_inet6_protosw = {
.type = SOCK_STREAM,
.protocol = IPPROTO_SMC,
.prot = &smc_inet6_prot,
.ops = &smc_inet6_stream_ops,
.flags = INET_PROTOSW_ICSK,
};
#endif /* CONFIG_IPV6 */
static unsigned int smc_sync_mss(struct sock *sk, u32 pmtu)
{
/* No need pass it through to clcsock, mss can always be set by
* sock_create_kern or smc_setsockopt.
*/
return 0;
}
static int smc_inet_init_sock(struct sock *sk)
{
struct net *net = sock_net(sk);
/* init common smc sock */
smc_sk_init(net, sk, IPPROTO_SMC);
inet_csk(sk)->icsk_sync_mss = smc_sync_mss;
/* create clcsock */
return smc_create_clcsk(net, sk, sk->sk_family);
}
int __init smc_inet_init(void)
{
int rc;
rc = proto_register(&smc_inet_prot, 1);
if (rc) {
pr_err("%s: proto_register smc_inet_prot fails with %d\n",
__func__, rc);
return rc;
}
/* no return value */
inet_register_protosw(&smc_inet_protosw);
#if IS_ENABLED(CONFIG_IPV6)
rc = proto_register(&smc_inet6_prot, 1);
if (rc) {
pr_err("%s: proto_register smc_inet6_prot fails with %d\n",
__func__, rc);
goto out_inet6_prot;
}
rc = inet6_register_protosw(&smc_inet6_protosw);
if (rc) {
pr_err("%s: inet6_register_protosw smc_inet6_protosw fails with %d\n",
__func__, rc);
goto out_inet6_protosw;
}
return rc;
out_inet6_protosw:
proto_unregister(&smc_inet6_prot);
out_inet6_prot:
inet_unregister_protosw(&smc_inet_protosw);
proto_unregister(&smc_inet_prot);
#endif /* CONFIG_IPV6 */
return rc;
}
void smc_inet_exit(void)
{
#if IS_ENABLED(CONFIG_IPV6)
inet6_unregister_protosw(&smc_inet6_protosw);
proto_unregister(&smc_inet6_prot);
#endif /* CONFIG_IPV6 */
inet_unregister_protosw(&smc_inet_protosw);
proto_unregister(&smc_inet_prot);
}