Решил попробовать проделать эту операцию через сокеты netlink вроде как и удобно и то что надо именно мне, однако наткнулся на очередной косяк - в определённых моментах ядро зависает и я не могу выяснить из-за чего
| Код |
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <net/sock.h>
#include <linux/socket.h>
#include <linux/net.h>
#include <asm/types.h>
#include <linux/netlink.h>
#include <linux/skbuff.h>
DEFINE_MUTEX(mut);
#define KNETLINK_UNIT 17
static struct sock * knetlink_sk = NULL;
char data_string[] = "Hello Userspace! This is msg from Kernel";
int knetlink_process( struct sk_buff * skb, struct nlmsghdr *nlh )
{
u8 * payload = NULL;
int payload_size;
int length;
int seq;
pid_t pid;
// struct sk_buff *rskb = NULL; //Сокет буферов для netlink
pid = nlh->nlmsg_pid;
length = nlh->nlmsg_len;
seq = nlh->nlmsg_seq;
printk("\nknetlink_process: nlmsg len %d type %d pid %d seq %d\n",
length, nlh->nlmsg_type, pid, seq );
/* обработка полезной нагрузки */
payload_size = nlh->nlmsg_len - NLMSG_LENGTH(0);
if ( payload_size > 0 ) {
payload = NLMSG_DATA(nlh);
printk("\nknetlink_process: Payload is %s ", payload);
}
// ответ пользовательскому приложению
struct sk_buff *rskb = alloc_skb( nlh->nlmsg_len, GFP_KERNEL );
if ( rskb ) {
printk("\nknetlink_process: replies with the same socket_buffer\n");
*rskb = *skb;
} else {
printk("WTF????!!!!");
/* skb_put( rskb, length );
kfree_skb( skb ); */
}
nlh = (struct nlmsghdr *)rskb->data;
nlh->nlmsg_len = length;
nlh->nlmsg_pid = pid;
nlh->nlmsg_flags = 0;
nlh->nlmsg_type = 2;
nlh->nlmsg_seq = seq++;
payload = NLMSG_DATA( nlh );
printk("\nknetlink_process: reply nlmsg len %d type %d pid %d\n",
nlh->nlmsg_len, nlh->nlmsg_type, nlh->nlmsg_pid );
// strlcpy(payload, data_string,nlh->nlmsg_len);
// *(payload + strlen(data_string)) = '\0';
NETLINK_CB(rskb).pid = 0; //from kernel
netlink_unicast( knetlink_sk, rskb, pid, MSG_DONTWAIT );
return 0;
}
void knetlink_input( struct sk_buff * skb)
{
mutex_lock(&mut);
printk("\nFunction %s() called", __FUNCTION__);
netlink_rcv_skb(skb, &knetlink_process);
mutex_unlock(&mut);
}
int knetlink_init( void ) //Управление передаётся при загрузке модуля
{
if ( knetlink_sk != NULL ) {
printk("knetlink_init: sock already present\n");
return 1;
}
//struct sock * netlink_kernel_create ---- это API для создания сокета из kernel_space
knetlink_sk = netlink_kernel_create(&init_net, KNETLINK_UNIT, 0, knetlink_input, NULL, THIS_MODULE);
if ( knetlink_sk == NULL ) {
printk("knetlink_init: sock fail\n");
return 1;
}
// (void*)knetlink_sk
printk("knetlink_init: sock %p\n", knetlink_sk->sk_socket);
return 0;
}
void knetlink_exit( void )
{
mutex_lock(&mut);
if ( knetlink_sk != NULL ) {
printk("\nknetlink_exit: release sock %p\n", knetlink_sk->sk_socket);
kfree_skb( knetlink_sk);
} else {
printk("knetlink_exit: warning sock is NULL\n");
}
mutex_unlock(&mut);
}
module_init( knetlink_init );
module_exit( knetlink_exit );
MODULE_LICENSE("GPL");
|
в логах
| Код |
knetlink_process: reply nlmsg len 1040 type 2 pid 5772
Mar 24 19:41:47 jamal kernel: [43646.512847] *pde = 00000000
Mar 24 19:41:47 jamal kernel: [43646.512878] Modules linked in: qazx_driver radeon ttm drm_kms_helper drm i2c_algo_bit uinput binfmt_misc ppdev lp parport sco bridge stp bnep rfcomm l2cap crc16 bluetooth vboxnetflt vboxnetadp vboxdrv powernow_k8 cpufreq_userspace cpufreq_stats cpufreq_powersave cpufreq_conservative reiserfs fuse firewire_sbp2 loop snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_pcm_oss uvcvideo snd_mixer_oss snd_pcm videodev v4l1_compat snd_seq_midi snd_rawmidi arc4 snd_seq_midi_event snd_seq ecb snd_timer snd_seq_device snd ath5k soundcore mac80211 ath i2c_piix4 snd_page_alloc cfg80211 serio_raw i2c_core asus_laptop evdev k8temp rfkill processor psmouse ac battery pcspkr ext3 jbd mbcache ide_cd_mod cdrom sd_mod crc_t10dif usbhid ata_generic hid ide_pci_generic ohci_hcd sdhci_pci sdhci ahci mmc_core libata atiixp ati_agp video output ricoh_mmc led_class firewire_ohci firewire_core crc_itu_t r8169 mii scsi_mod ehci_hcd button ide_core agpgart usbcore nls_base thermal fan thermal_
Mar 24 19:41:47 jamal kernel: sys [last unloaded: scsi_wait_scan]
Mar 24 19:41:47 jamal kernel: [43646.513081]
Mar 24 19:41:47 jamal kernel: [43646.513092] Pid: 2918, comm: yakuake Not tainted (2.6.32-3-686 #1) F3Ka
Mar 24 19:41:47 jamal kernel: [43646.513103] EIP: 0060:[<c10ae892>] EFLAGS: 00010002 CPU: 0
Mar 24 19:41:47 jamal kernel: [43646.513114] EIP is at __kmalloc_track_caller+0xb5/0x124
Mar 24 19:41:47 jamal kernel: [43646.513122] EAX: 00000000 EBX: 6972616d ECX: 00000800 EDX: c2804f5c
Mar 24 19:41:47 jamal kernel: [43646.513129] ESI: c136c5ec EDI: 00000246 EBP: 000004d0 ESP: f2407d28
Mar 24 19:41:47 jamal kernel: [43646.513137] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Mar 24 19:41:47 jamal kernel: [43646.513157] f24de000 c11c12df 000004d0 00000470 00000800 f425cf00 00000320 000004d0
Mar 24 19:41:47 jamal kernel: [43646.513173] <0> c136bcc8 c11c5052 c12eb76e 00000000 f37f6800 00000000 f2407e4c 000004d0
Mar 24 19:41:47 jamal kernel: [43646.513189] <0> c11c12df ffffffff f2408000 00000000 00000314 f37f68dc 00000000 00000001
Mar 24 19:41:47 jamal kernel: [43646.513225] [<c11c12df>] ? sock_alloc_send_pskb+0x8e/0x257
Mar 24 19:41:47 jamal kernel: [43646.513238] [<c11c5052>] ? __alloc_skb+0x4a/0x115
Mar 24 19:41:47 jamal kernel: [43646.513247] [<c11c12df>] ? sock_alloc_send_pskb+0x8e/0x257
Mar 24 19:41:47 jamal kernel: [43646.513263] [<c108bd02>] ? get_page_from_freelist+0x33a/0x3c7
Mar 24 19:41:47 jamal kernel: [43646.513273] [<c11c14b4>] ? sock_alloc_send_skb+0xc/0xf
Mar 24 19:41:47 jamal kernel: [43646.513285] [<c1221e8b>] ? unix_stream_sendmsg+0x12c/0x29c
Mar 24 19:41:47 jamal kernel: [43646.513299] [<c11be621>] ? __sock_sendmsg+0x43/0x4a
Mar 24 19:41:47 jamal kernel: [43646.513309] [<c11be6cb>] ? sock_aio_write+0xa3/0xb0
Mar 24 19:41:47 jamal kernel: [43646.513324] [<c1101c86>] ? security_task_to_inode+0xc/0xd
Mar 24 19:41:47 jamal kernel: [43646.513337] [<c10b2c2d>] ? do_sync_readv_writev+0xb8/0xf9
Mar 24 19:41:47 jamal kernel: [43646.513353] [<c1044412>] ? autoremove_wake_function+0x0/0x2d
Mar 24 19:41:47 jamal kernel: [43646.513364] [<c10b2ada>] ? rw_copy_check_uvector+0x59/0xc3
Mar 24 19:41:47 jamal kernel: [43646.513375] [<c1046698>] ? hrtimer_forward+0x10c/0x124
Mar 24 19:41:47 jamal kernel: [43646.513387] [<c1101a4c>] ? security_file_permission+0xc/0xd
Mar 24 19:41:47 jamal kernel: [43646.513396] [<c10b32b0>] ? do_readv_writev+0x81/0xd6
Mar 24 19:41:47 jamal kernel: [43646.513407] [<c11be628>] ? sock_aio_write+0x0/0xb0
Mar 24 19:41:47 jamal kernel: [43646.513421] [<c106f2c5>] ? __rcu_process_callbacks+0x6c/0x227
Mar 24 19:41:47 jamal kernel: [43646.513431] [<c106f4b3>] ? rcu_process_callbacks+0x33/0x39
Mar 24 19:41:47 jamal kernel: [43646.513441] [<c10b333c>] ? vfs_writev+0x37/0x43
Mar 24 19:41:47 jamal kernel: [43646.513450] [<c10b341d>] ? sys_writev+0x3c/0x91
Mar 24 19:41:47 jamal kernel: [43646.513463] [<c10030fb>] ? sysenter_do_call+0x12/0x28
Mar 24 19:41:47 jamal kernel: [43646.513572] ---[ end trace 316eb84841ca08b7 ]---
Mar 24 19:41:47 jamal kernel: [43646.550269] *pde = 00000000
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Зависание чаще всего происходит после выгрузки модуля, но не сразу, а через некоторое время, когда, например, пытаюсь запустить MC
Также был замечан случай когда зависало после ответа пользователю : knetlink_process: reply nlmsg len 1040 type 2 pid 5772. |
