syzkaller-repros/linux/6889c70bb2642156f5eaeac3c933fe52517285df.c

// WARNING: refcount bug in sock_wfree
// https://syzkaller.appspot.com/bug?id=6889c70bb2642156f5eaeac3c933fe52517285df
// status:open
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <arpa/inet.h>
#include <endian.h>
#include <fcntl.h>
#include <net/if.h>
#include <netinet/in.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>

#include <linux/genetlink.h>
#include <linux/if_addr.h>
#include <linux/if_link.h>
#include <linux/in6.h>
#include <linux/neighbour.h>
#include <linux/net.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/veth.h>

struct nlmsg {
  char* pos;
  int nesting;
  struct nlattr* nested[8];
  char buf[1024];
};

static struct nlmsg nlmsg;

static void netlink_init(struct nlmsg* nlmsg, int typ, int flags,
                         const void* data, int size)
{
  memset(nlmsg, 0, sizeof(*nlmsg));
  struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf;
  hdr->nlmsg_type = typ;
  hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | flags;
  memcpy(hdr + 1, data, size);
  nlmsg->pos = (char*)(hdr + 1) + NLMSG_ALIGN(size);
}

static void netlink_attr(struct nlmsg* nlmsg, int typ, const void* data,
                         int size)
{
  struct nlattr* attr = (struct nlattr*)nlmsg->pos;
  attr->nla_len = sizeof(*attr) + size;
  attr->nla_type = typ;
  memcpy(attr + 1, data, size);
  nlmsg->pos += NLMSG_ALIGN(attr->nla_len);
}

static int netlink_send_ext(struct nlmsg* nlmsg, int sock, uint16_t reply_type,
                            int* reply_len)
{
  if (nlmsg->pos > nlmsg->buf + sizeof(nlmsg->buf) || nlmsg->nesting)
    exit(1);
  struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf;
  hdr->nlmsg_len = nlmsg->pos - nlmsg->buf;
  struct sockaddr_nl addr;
  memset(&addr, 0, sizeof(addr));
  addr.nl_family = AF_NETLINK;
  unsigned n = sendto(sock, nlmsg->buf, hdr->nlmsg_len, 0,
                      (struct sockaddr*)&addr, sizeof(addr));
  if (n != hdr->nlmsg_len)
    exit(1);
  n = recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0);
  if (hdr->nlmsg_type == NLMSG_DONE) {
    *reply_len = 0;
    return 0;
  }
  if (n < sizeof(struct nlmsghdr))
    exit(1);
  if (reply_len && hdr->nlmsg_type == reply_type) {
    *reply_len = n;
    return 0;
  }
  if (n < sizeof(struct nlmsghdr) + sizeof(struct nlmsgerr))
    exit(1);
  if (hdr->nlmsg_type != NLMSG_ERROR)
    exit(1);
  return -((struct nlmsgerr*)(hdr + 1))->error;
}

static int netlink_send(struct nlmsg* nlmsg, int sock)
{
  return netlink_send_ext(nlmsg, sock, 0, NULL);
}

static int netlink_next_msg(struct nlmsg* nlmsg, unsigned int offset,
                            unsigned int total_len)
{
  struct nlmsghdr* hdr = (struct nlmsghdr*)(nlmsg->buf + offset);
  if (offset == total_len || offset + hdr->nlmsg_len > total_len)
    return -1;
  return hdr->nlmsg_len;
}

static void netlink_device_change(struct nlmsg* nlmsg, int sock,
                                  const char* name, bool up, const char* master,
                                  const void* mac, int macsize,
                                  const char* new_name)
{
  struct ifinfomsg hdr;
  memset(&hdr, 0, sizeof(hdr));
  if (up)
    hdr.ifi_flags = hdr.ifi_change = IFF_UP;
  hdr.ifi_index = if_nametoindex(name);
  netlink_init(nlmsg, RTM_NEWLINK, 0, &hdr, sizeof(hdr));
  if (new_name)
    netlink_attr(nlmsg, IFLA_IFNAME, new_name, strlen(new_name));
  if (master) {
    int ifindex = if_nametoindex(master);
    netlink_attr(nlmsg, IFLA_MASTER, &ifindex, sizeof(ifindex));
  }
  if (macsize)
    netlink_attr(nlmsg, IFLA_ADDRESS, mac, macsize);
  int err = netlink_send(nlmsg, sock);
  (void)err;
}

const int kInitNetNsFd = 239;

#define DEVLINK_FAMILY_NAME "devlink"

#define DEVLINK_CMD_PORT_GET 5
#define DEVLINK_CMD_RELOAD 37
#define DEVLINK_ATTR_BUS_NAME 1
#define DEVLINK_ATTR_DEV_NAME 2
#define DEVLINK_ATTR_NETDEV_NAME 7
#define DEVLINK_ATTR_NETNS_FD 137

static int netlink_devlink_id_get(struct nlmsg* nlmsg, int sock)
{
  struct genlmsghdr genlhdr;
  struct nlattr* attr;
  int err, n;
  uint16_t id = 0;
  memset(&genlhdr, 0, sizeof(genlhdr));
  genlhdr.cmd = CTRL_CMD_GETFAMILY;
  netlink_init(nlmsg, GENL_ID_CTRL, 0, &genlhdr, sizeof(genlhdr));
  netlink_attr(nlmsg, CTRL_ATTR_FAMILY_NAME, DEVLINK_FAMILY_NAME,
               strlen(DEVLINK_FAMILY_NAME) + 1);
  err = netlink_send_ext(nlmsg, sock, GENL_ID_CTRL, &n);
  if (err) {
    return -1;
  }
  attr = (struct nlattr*)(nlmsg->buf + NLMSG_HDRLEN +
                          NLMSG_ALIGN(sizeof(genlhdr)));
  for (; (char*)attr < nlmsg->buf + n;
       attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) {
    if (attr->nla_type == CTRL_ATTR_FAMILY_ID) {
      id = *(uint16_t*)(attr + 1);
      break;
    }
  }
  if (!id) {
    return -1;
  }
  recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); /* recv ack */
  return id;
}

static void netlink_devlink_netns_move(const char* bus_name,
                                       const char* dev_name, int netns_fd)
{
  struct genlmsghdr genlhdr;
  int sock;
  int id;
  sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC);
  if (sock == -1)
    exit(1);
  id = netlink_devlink_id_get(&nlmsg, sock);
  if (id == -1)
    goto error;
  memset(&genlhdr, 0, sizeof(genlhdr));
  genlhdr.cmd = DEVLINK_CMD_RELOAD;
  netlink_init(&nlmsg, id, 0, &genlhdr, sizeof(genlhdr));
  netlink_attr(&nlmsg, DEVLINK_ATTR_BUS_NAME, bus_name, strlen(bus_name) + 1);
  netlink_attr(&nlmsg, DEVLINK_ATTR_DEV_NAME, dev_name, strlen(dev_name) + 1);
  netlink_attr(&nlmsg, DEVLINK_ATTR_NETNS_FD, &netns_fd, sizeof(netns_fd));
  netlink_send(&nlmsg, sock);
error:
  close(sock);
}

static struct nlmsg nlmsg2;

static void initialize_devlink_ports(const char* bus_name, const char* dev_name,
                                     const char* netdev_prefix)
{
  struct genlmsghdr genlhdr;
  int len, total_len, id, err, offset;
  uint16_t netdev_index;
  int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC);
  if (sock == -1)
    exit(1);
  int rtsock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
  if (rtsock == -1)
    exit(1);
  id = netlink_devlink_id_get(&nlmsg, sock);
  if (id == -1)
    goto error;
  memset(&genlhdr, 0, sizeof(genlhdr));
  genlhdr.cmd = DEVLINK_CMD_PORT_GET;
  netlink_init(&nlmsg, id, NLM_F_DUMP, &genlhdr, sizeof(genlhdr));
  netlink_attr(&nlmsg, DEVLINK_ATTR_BUS_NAME, bus_name, strlen(bus_name) + 1);
  netlink_attr(&nlmsg, DEVLINK_ATTR_DEV_NAME, dev_name, strlen(dev_name) + 1);
  err = netlink_send_ext(&nlmsg, sock, id, &total_len);
  if (err) {
    goto error;
  }
  offset = 0;
  netdev_index = 0;
  while ((len = netlink_next_msg(&nlmsg, offset, total_len)) != -1) {
    struct nlattr* attr = (struct nlattr*)(nlmsg.buf + offset + NLMSG_HDRLEN +
                                           NLMSG_ALIGN(sizeof(genlhdr)));
    for (; (char*)attr < nlmsg.buf + offset + len;
         attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) {
      if (attr->nla_type == DEVLINK_ATTR_NETDEV_NAME) {
        char* port_name;
        char netdev_name[IFNAMSIZ];
        port_name = (char*)(attr + 1);
        snprintf(netdev_name, sizeof(netdev_name), "%s%d", netdev_prefix,
                 netdev_index);
        netlink_device_change(&nlmsg2, rtsock, port_name, true, 0, 0, 0,
                              netdev_name);
        break;
      }
    }
    offset += len;
    netdev_index++;
  }
error:
  close(rtsock);
  close(sock);
}

static void initialize_devlink_pci(void)
{
  int netns = open("/proc/self/ns/net", O_RDONLY);
  if (netns == -1)
    exit(1);
  int ret = setns(kInitNetNsFd, 0);
  if (ret == -1)
    exit(1);
  netlink_devlink_netns_move("pci", "0000:00:10.0", netns);
  ret = setns(netns, 0);
  if (ret == -1)
    exit(1);
  close(netns);
  initialize_devlink_ports("pci", "0000:00:10.0", "netpci");
}

uint64_t r[5] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff,
                 0xffffffffffffffff, 0x0};

int main(void)
{
  syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 3ul, 0x32ul, -1, 0);
  intptr_t res = 0;
  *(uint16_t*)0x20000000 = 0;
  *(uint16_t*)0x20000002 = 7;
  *(uint8_t*)0x20000004 = 0xaa;
  *(uint8_t*)0x20000005 = 0xaa;
  *(uint8_t*)0x20000006 = 0xaa;
  *(uint8_t*)0x20000007 = 0xaa;
  *(uint8_t*)0x20000008 = 0xaa;
  *(uint8_t*)0x20000009 = 0;
  *(uint8_t*)0x2000000a = 1;
  *(uint8_t*)0x2000000b = 0x80;
  *(uint8_t*)0x2000000c = 0xc2;
  *(uint8_t*)0x2000000d = 0;
  *(uint8_t*)0x2000000e = 0;
  *(uint8_t*)0x2000000f = 0;
  *(uint8_t*)0x20000010 = 0xaa;
  *(uint8_t*)0x20000011 = 0xaa;
  *(uint8_t*)0x20000012 = 0xaa;
  *(uint8_t*)0x20000013 = 0xaa;
  *(uint8_t*)0x20000014 = 0xaa;
  *(uint8_t*)0x20000015 = 0;
  *(uint8_t*)0x20000016 = 0;
  *(uint8_t*)0x20000017 = 0;
  *(uint8_t*)0x20000018 = 0;
  *(uint8_t*)0x20000019 = 0;
  *(uint8_t*)0x2000001a = 0;
  *(uint8_t*)0x2000001b = 0;
  *(uint8_t*)0x2000001c = 0xaa;
  *(uint8_t*)0x2000001d = 0xaa;
  *(uint8_t*)0x2000001e = 0xaa;
  *(uint8_t*)0x2000001f = 0xaa;
  *(uint8_t*)0x20000020 = 0xaa;
  *(uint8_t*)0x20000021 = 0xbb;
  *(uint8_t*)0x20000022 = 0xaa;
  *(uint8_t*)0x20000023 = 0xaa;
  *(uint8_t*)0x20000024 = 0xaa;
  *(uint8_t*)0x20000025 = 0xaa;
  *(uint8_t*)0x20000026 = 0xaa;
  *(uint8_t*)0x20000027 = 0xbb;
  *(uint8_t*)0x20000028 = 0xaa;
  *(uint8_t*)0x20000029 = 0xaa;
  *(uint8_t*)0x2000002a = 0xaa;
  *(uint8_t*)0x2000002b = 0xaa;
  *(uint8_t*)0x2000002c = 0xaa;
  *(uint8_t*)0x2000002d = 0xbb;
  syscall(__NR_ioctl, -1, 0x400454d1ul, 0x20000000ul);
  res = syscall(__NR_socket, 0x10ul, 3ul, 0ul);
  if (res != -1)
    r[0] = res;
  *(uint64_t*)0x20000080 = 0;
  *(uint32_t*)0x20000088 = 0;
  *(uint64_t*)0x20000090 = 0x20000040;
  *(uint64_t*)0x20000040 = 0x20000000;
  *(uint32_t*)0x20000000 = 0x30;
  *(uint16_t*)0x20000004 = 0x10;
  *(uint16_t*)0x20000006 = 0x801;
  *(uint32_t*)0x20000008 = 0;
  *(uint32_t*)0x2000000c = 0;
  *(uint8_t*)0x20000010 = 0;
  *(uint8_t*)0x20000011 = 0;
  *(uint16_t*)0x20000012 = 0;
  *(uint32_t*)0x20000014 = 0;
  *(uint32_t*)0x20000018 = 0;
  *(uint32_t*)0x2000001c = 0;
  *(uint16_t*)0x20000020 = 8;
  *(uint16_t*)0x20000022 = 0x1b;
  *(uint32_t*)0x20000024 = 0;
  *(uint16_t*)0x20000028 = 8;
  *(uint16_t*)0x2000002a = 4;
  *(uint8_t*)0x2000002c = 0;
  *(uint64_t*)0x20000048 = 0x30;
  *(uint64_t*)0x20000098 = 1;
  *(uint64_t*)0x200000a0 = 0;
  *(uint64_t*)0x200000a8 = 0;
  *(uint32_t*)0x200000b0 = 0;
  syscall(__NR_sendmsg, r[0], 0x20000080ul, 0ul);
  res = syscall(__NR_socket, 2ul, 0x4000000805ul, 0);
  if (res != -1)
    r[1] = res;
  res = syscall(__NR_socket, 2ul, 5ul, 0x84ul);
  if (res != -1)
    r[2] = res;
  res = syscall(__NR_dup3, r[1], r[2], 0ul);
  if (res != -1)
    r[3] = res;
  *(uint16_t*)0x20d6cff0 = 2;
  *(uint16_t*)0x20d6cff2 = htobe16(0x4e20);
  *(uint32_t*)0x20d6cff4 = htobe32(0x7f000001);
  syscall(__NR_setsockopt, r[2], 0x84ul, 0x64ul, 0x20d6cff0ul, 0x10ul);
  memcpy((void*)0x20fa3fff, "\t", 1);
  *(uint16_t*)0x206f7000 = 2;
  *(uint16_t*)0x206f7002 = htobe16(0);
  *(uint8_t*)0x206f7004 = 0xac;
  *(uint8_t*)0x206f7005 = 0x14;
  *(uint8_t*)0x206f7006 = -1;
  *(uint8_t*)0x206f7007 = 0xbb;
  syscall(__NR_sendto, r[3], 0x20fa3ffful, 1ul, 0ul, 0x206f7000ul, 0x10ul);
  memcpy((void*)0x203cef9f, "7", 1);
  *(uint16_t*)0x20618000 = 2;
  *(uint16_t*)0x20618002 = htobe16(0x4e20);
  *(uint32_t*)0x20618004 = htobe32(0x7f000001);
  syscall(__NR_sendto, r[2], 0x203cef9ful, 0xff46ul, 0ul, 0x20618000ul, 0x10ul);
  *(uint32_t*)0x20a8a000 = 0xc;
  res = syscall(__NR_getsockopt, r[2], 0x84ul, 0x1dul, 0x2025e000ul,
                0x20a8a000ul);
  if (res != -1)
    r[4] = *(uint32_t*)0x2025e008;
  *(uint32_t*)0x2059aff8 = r[4];
  *(uint32_t*)0x2059affc = 0;
  *(uint32_t*)0x2034f000 = 0x2059b000;
  syscall(__NR_getsockopt, r[3], 0x84ul, 0x7aul, 0x2059aff8ul, 0x2034f000ul);
  return 0;
}