[PATCH 5.0 61/89] net: netrom: Fix error cleanup path of nr_proto_init

From: YueHaibing yuehaibing@huawei.com

commit d3706566ae3d92677b932dd156157fd6c72534b1 upstream.

Syzkaller report this:

BUG: unable to handle kernel paging request at fffffbfff830524b PGD 237fe8067 P4D 237fe8067 PUD 237e64067 PMD 1c9716067 PTE 0 Oops: 0000 [#1] SMP KASAN PTI CPU: 1 PID: 4465 Comm: syz-executor.0 Not tainted 5.0.0+ #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 RIP: 0010:__list_add_valid+0x21/0xe0 lib/list_debug.c:23 Code: 8b 0c 24 e9 17 fd ff ff 90 55 48 89 fd 48 8d 7a 08 53 48 89 d3 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 48 83 ec 08 <80> 3c 02 00 0f 85 8b 00 00 00 48 8b 53 08 48 39 f2 75 35 48 89 f2 RSP: 0018:ffff8881ea2278d0 EFLAGS: 00010282 RAX: dffffc0000000000 RBX: ffffffffc1829250 RCX: 1ffff1103d444ef4 RDX: 1ffffffff830524b RSI: ffffffff85659300 RDI: ffffffffc1829258 RBP: ffffffffc1879250 R08: fffffbfff0acb269 R09: fffffbfff0acb269 R10: ffff8881ea2278f0 R11: fffffbfff0acb268 R12: ffffffffc1829250 R13: dffffc0000000000 R14: 0000000000000008 R15: ffffffffc187c830 FS: 00007fe0361df700(0000) GS:ffff8881f7300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: fffffbfff830524b CR3: 00000001eb39a001 CR4: 00000000007606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: __list_add include/linux/list.h:60 [inline] list_add include/linux/list.h:79 [inline] proto_register+0x444/0x8f0 net/core/sock.c:3375 nr_proto_init+0x73/0x4b3 [netrom] ? 0xffffffffc1628000 ? 0xffffffffc1628000 do_one_initcall+0xbc/0x47d init/main.c:887 do_init_module+0x1b5/0x547 kernel/module.c:3456 load_module+0x6405/0x8c10 kernel/module.c:3804 __do_sys_finit_module+0x162/0x190 kernel/module.c:3898 do_syscall_64+0x9f/0x450 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x462e99 Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe0361dec58 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000462e99 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00007fe0361dec70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe0361df6bc R13: 00000000004bcefa R14: 00000000006f6fb0 R15: 0000000000000004 Modules linked in: netrom(+) ax25 fcrypt pcbc af_alg arizona_ldo1 v4l2_common videodev media v4l2_dv_timings hdlc ide_cd_mod snd_soc_sigmadsp_regmap snd_soc_sigmadsp intel_spi_platform intel_spi mtd spi_nor snd_usbmidi_lib usbcore lcd ti_ads7950 hi6421_regulator snd_soc_kbl_rt5663_max98927 snd_soc_hdac_hdmi snd_hda_ext_core snd_hda_core snd_soc_rt5663 snd_soc_core snd_pcm_dmaengine snd_compress snd_soc_rl6231 mac80211 rtc_rc5t583 spi_slave_time leds_pwm hid_gt683r hid industrialio_triggered_buffer kfifo_buf industrialio ir_kbd_i2c rc_core led_class_flash dwc_xlgmac snd_ymfpci gameport snd_mpu401_uart snd_rawmidi snd_ac97_codec snd_pcm ac97_bus snd_opl3_lib snd_timer snd_seq_device snd_hwdep snd soundcore iptable_security iptable_raw iptable_mangle iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_filter bpfilter ip6_vti ip_vti ip_gre ipip sit tunnel4 ip_tunnel hsr veth netdevsim vxcan batman_adv cfg80211 rfkill chnl_net caif nlmon dummy team bonding vcan bridge stp llc ip6_gre gre ip6_tunnel tunnel6 tun joydev mousedev ppdev tpm kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel ide_pci_generic piix aesni_intel aes_x86_64 crypto_simd cryptd glue_helper ide_core psmouse input_leds i2c_piix4 serio_raw intel_agp intel_gtt ata_generic agpgart pata_acpi parport_pc rtc_cmos parport floppy sch_fq_codel ip_tables x_tables sha1_ssse3 sha1_generic ipv6 [last unloaded: rxrpc] Dumping ftrace buffer: (ftrace buffer empty) CR2: fffffbfff830524b ---[ end trace 039ab24b305c4b19 ]---

If nr_proto_init failed, it may forget to call proto_unregister, tiggering this issue.This patch rearrange code of nr_proto_init to avoid such issues.

Reported-by: Hulk Robot hulkci@huawei.com Signed-off-by: YueHaibing yuehaibing@huawei.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- include/net/netrom.h | 2 - net/netrom/af_netrom.c | 76 +++++++++++++++++++++++++++++------------ net/netrom/nr_loopback.c | 2 - net/netrom/nr_route.c | 2 - net/netrom/sysctl_net_netrom.c | 5 ++ 5 files changed, 61 insertions(+), 26 deletions(-)

--- a/include/net/netrom.h +++ b/include/net/netrom.h @@ -266,7 +266,7 @@ void nr_stop_idletimer(struct sock *); int nr_t1timer_running(struct sock *);

/* sysctl_net_netrom.c */ -void nr_register_sysctl(void); +int nr_register_sysctl(void); void nr_unregister_sysctl(void);

#endif --- a/net/netrom/af_netrom.c +++ b/net/netrom/af_netrom.c @@ -1392,18 +1392,22 @@ static int __init nr_proto_init(void) int i; int rc = proto_register(&nr_proto, 0);

- if (rc != 0) - goto out; + if (rc) + return rc;

if (nr_ndevs > 0x7fffffff/sizeof(struct net_device *)) { - printk(KERN_ERR "NET/ROM: nr_proto_init - nr_ndevs parameter to large\n"); - return -1; + pr_err("NET/ROM: %s - nr_ndevs parameter too large\n", + __func__); + rc = -EINVAL; + goto unregister_proto; }

dev_nr = kcalloc(nr_ndevs, sizeof(struct net_device *), GFP_KERNEL); - if (dev_nr == NULL) { - printk(KERN_ERR "NET/ROM: nr_proto_init - unable to allocate device array\n"); - return -1; + if (!dev_nr) { + pr_err("NET/ROM: %s - unable to allocate device array\n", + __func__); + rc = -ENOMEM; + goto unregister_proto; }

for (i = 0; i < nr_ndevs; i++) { @@ -1413,13 +1417,13 @@ static int __init nr_proto_init(void) sprintf(name, "nr%d", i); dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, nr_setup); if (!dev) { - printk(KERN_ERR "NET/ROM: nr_proto_init - unable to allocate device structure\n"); + rc = -ENOMEM; goto fail; }

dev->base_addr = i; - if (register_netdev(dev)) { - printk(KERN_ERR "NET/ROM: nr_proto_init - unable to register network device\n"); + rc = register_netdev(dev); + if (rc) { free_netdev(dev); goto fail; } @@ -1427,36 +1431,64 @@ static int __init nr_proto_init(void) dev_nr[i] = dev; }

- if (sock_register(&nr_family_ops)) { - printk(KERN_ERR "NET/ROM: nr_proto_init - unable to register socket family\n"); + rc = sock_register(&nr_family_ops); + if (rc) goto fail; - }

- register_netdevice_notifier(&nr_dev_notifier); + rc = register_netdevice_notifier(&nr_dev_notifier); + if (rc) + goto out_sock;

ax25_register_pid(&nr_pid); ax25_linkfail_register(&nr_linkfail_notifier);

#ifdef CONFIG_SYSCTL - nr_register_sysctl(); + rc = nr_register_sysctl(); + if (rc) + goto out_sysctl; #endif

nr_loopback_init();

- proc_create_seq("nr", 0444, init_net.proc_net, &nr_info_seqops); - proc_create_seq("nr_neigh", 0444, init_net.proc_net, &nr_neigh_seqops); - proc_create_seq("nr_nodes", 0444, init_net.proc_net, &nr_node_seqops); -out: - return rc; + rc = -ENOMEM; + if (!proc_create_seq("nr", 0444, init_net.proc_net, &nr_info_seqops)) + goto proc_remove1; + if (!proc_create_seq("nr_neigh", 0444, init_net.proc_net, + &nr_neigh_seqops)) + goto proc_remove2; + if (!proc_create_seq("nr_nodes", 0444, init_net.proc_net, + &nr_node_seqops)) + goto proc_remove3; + + return 0; + +proc_remove3: + remove_proc_entry("nr_neigh", init_net.proc_net); +proc_remove2: + remove_proc_entry("nr", init_net.proc_net); +proc_remove1: + + nr_loopback_clear(); + nr_rt_free(); + +#ifdef CONFIG_SYSCTL + nr_unregister_sysctl(); +out_sysctl: +#endif + ax25_linkfail_release(&nr_linkfail_notifier); + ax25_protocol_release(AX25_P_NETROM); + unregister_netdevice_notifier(&nr_dev_notifier); +out_sock: + sock_unregister(PF_NETROM); fail: while (--i >= 0) { unregister_netdev(dev_nr[i]); free_netdev(dev_nr[i]); } kfree(dev_nr); +unregister_proto: proto_unregister(&nr_proto); - rc = -1; - goto out; + return rc; }

module_init(nr_proto_init); --- a/net/netrom/nr_loopback.c +++ b/net/netrom/nr_loopback.c @@ -70,7 +70,7 @@ static void nr_loopback_timer(struct tim } }

-void __exit nr_loopback_clear(void) +void nr_loopback_clear(void) { del_timer_sync(&loopback_timer); skb_queue_purge(&loopback_queue); --- a/net/netrom/nr_route.c +++ b/net/netrom/nr_route.c @@ -953,7 +953,7 @@ const struct seq_operations nr_neigh_seq /* * Free all memory associated with the nodes and routes lists. */ -void __exit nr_rt_free(void) +void nr_rt_free(void) { struct nr_neigh *s = NULL; struct nr_node *t = NULL; --- a/net/netrom/sysctl_net_netrom.c +++ b/net/netrom/sysctl_net_netrom.c @@ -146,9 +146,12 @@ static struct ctl_table nr_table[] = { { } };

-void __init nr_register_sysctl(void) +int __init nr_register_sysctl(void) { nr_table_header = register_net_sysctl(&init_net, "net/netrom", nr_table); + if (!nr_table_header) + return -ENOMEM; + return 0; }

void nr_unregister_sysctl(void)