syzkaller-repros/linux/826185a3ca17eb363147ce23a041ca1389b89ce3.c

// BUG: unable to handle kernel NULL pointer dereference in vb2_vmalloc_put
// https://syzkaller.appspot.com/bug?id=826185a3ca17eb363147ce23a041ca1389b89ce3
// 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/stat.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 138

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, err;
  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));
  err = netlink_send(&nlmsg, sock);
  if (err) {
  }
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");
}

static long syz_open_dev(volatile long a0, volatile long a1, volatile long a2)
{
  if (a0 == 0xc || a0 == 0xb) {
    char buf[128];
    sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1,
            (uint8_t)a2);
    return open(buf, O_RDWR, 0);
  } else {
    char buf[1024];
    char* hash;
    strncpy(buf, (char*)a0, sizeof(buf) - 1);
    buf[sizeof(buf) - 1] = 0;
    while ((hash = strchr(buf, '#'))) {
      *hash = '0' + (char)(a1 % 10);
      a1 /= 10;
    }
    return open(buf, a2, 0);
  }
}

uint64_t r[1] = {0xffffffffffffffff};

int main(void)
{
  syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 3ul, 0x32ul, -1, 0);
  intptr_t res = 0;
  memcpy((void*)0x20000040, "/dev/swradio#\000", 14);
  res = syz_open_dev(0x20000040, 0, 2);
  if (res != -1)
    r[0] = res;
  *(uint32_t*)0x20000240 = 0;
  *(uint32_t*)0x20000244 = 9;
  *(uint32_t*)0x20000248 = 1;
  *(uint32_t*)0x20000250 = 0xb;
  *(uint32_t*)0x20000258 = 0;
  *(uint32_t*)0x2000025c = 1;
  *(uint32_t*)0x20000260 = 0;
  *(uint32_t*)0x20000264 = 0;
  *(uint32_t*)0x20000268 = 0;
  *(uint32_t*)0x2000026c = 0;
  *(uint32_t*)0x20000270 = 0;
  *(uint32_t*)0x20000274 = 0;
  *(uint32_t*)0x20000278 = 0;
  *(uint32_t*)0x2000027c = 0;
  *(uint32_t*)0x20000280 = 0;
  *(uint32_t*)0x20000284 = 0;
  *(uint32_t*)0x20000320 = 0;
  *(uint32_t*)0x20000324 = 0;
  *(uint32_t*)0x20000328 = 0;
  *(uint32_t*)0x2000032c = 0;
  *(uint32_t*)0x20000330 = 0;
  *(uint32_t*)0x20000334 = 0;
  *(uint32_t*)0x20000338 = 0;
  *(uint32_t*)0x2000033c = 0;
  syscall(__NR_ioctl, r[0], 0xc100565cul, 0x20000240ul);
  *(uint32_t*)0x20000080 = 0;
  *(uint32_t*)0x20000084 = 7;
  *(uint32_t*)0x20000088 = 4;
  *(uint32_t*)0x20000090 = 0xb;
  memcpy((void*)0x20000098,
         "\x14\xfc\x58\xf1\x28\xe5\x22\x3c\x7e\x54\x61\xc1\xde\xb1\x2c\xe3\x35"
         "\xf6\x2b\x63\x77\x70\xf6\x0a\x8a\xff\xae\x2d\x1b\xc8\x14\x41\x13\x6a"
         "\x91\x14\x4f\xd1\xb0\x65\x62\xaf\x3b\xc8\x12\xfd\x93\x1b\xb7\x4e\x88"
         "\x5c\xaf\x25\xe0\x48\x9e\x79\xcb\xe5\xfe\x93\xff\xb5\x42\x66\x0a\xbf"
         "\x40\x6d\x45\xac\xf6\xc0\x89\xef\x7d\x24\x2f\xce\x2a\xf0\xdc\x66\x23"
         "\x48\xa0\xaa\x77\x0e\x6c\x5e\x3b\x62\x21\xf2\xb7\x12\x7d\x58\x29\x72"
         "\xd1\x33\x64\x43\x41\x68\x01\x7a\x7c\xd4\xf5\x9b\x0e\x98\x4d\x8c\xea"
         "\xb1\x4f\x2b\xfb\x0e\xe1\x3b\xc9\x93\x50\x9f\x1b\x40\xfb\xec\x11\x45"
         "\x47\x39\x08\xcb\xb3\x63\xf4\xa5\xb9\xed\xa2\x49\x0b\x6e\x7b\xf3\xb2"
         "\x81\xfc\x35\xd0\xca\x4b\xaa\xf9\x8c\x19\xa8\xb1\x12\x6f\x18\x28\xb8"
         "\xa3\xd1\xdc\x60\x7f\xb5\xf1\x67\x1b\x16\x8e\xe5\x1e\x9c\x1f\x60\x72"
         "\x30\x09\x29\x4f\x9d\x74\xef\x3e\x03\xea\xbd\x5a\x33",
         200);
  *(uint32_t*)0x20000160 = 0;
  *(uint32_t*)0x20000164 = 0;
  *(uint32_t*)0x20000168 = 0;
  *(uint32_t*)0x2000016c = 0;
  *(uint32_t*)0x20000170 = 0;
  *(uint32_t*)0x20000174 = 0;
  *(uint32_t*)0x20000178 = 0;
  *(uint32_t*)0x2000017c = 0;
  syscall(__NR_ioctl, r[0], 0xc100565cul, 0x20000080ul);
  return 0;
}