| /* |
| * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) |
| * Licensed under the GPL |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <errno.h> |
| #include <signal.h> |
| #include <fcntl.h> |
| #include <sys/mman.h> |
| #include <sys/ptrace.h> |
| #include <sys/wait.h> |
| #include <asm/unistd.h> |
| #include <init.h> |
| #include <longjmp.h> |
| #include <os.h> |
| #include <skas_ptrace.h> |
| |
| #define ARBITRARY_ADDR -1 |
| #define FAILURE_PID -1 |
| |
| #define STAT_PATH_LEN sizeof("/proc/#######/stat\0") |
| #define COMM_SCANF "%*[^)])" |
| |
| unsigned long os_process_pc(int pid) |
| { |
| char proc_stat[STAT_PATH_LEN], buf[256]; |
| unsigned long pc = ARBITRARY_ADDR; |
| int fd, err; |
| |
| sprintf(proc_stat, "/proc/%d/stat", pid); |
| fd = open(proc_stat, O_RDONLY, 0); |
| if (fd < 0) { |
| printk(UM_KERN_ERR "os_process_pc - couldn't open '%s', " |
| "errno = %d\n", proc_stat, errno); |
| goto out; |
| } |
| CATCH_EINTR(err = read(fd, buf, sizeof(buf))); |
| if (err < 0) { |
| printk(UM_KERN_ERR "os_process_pc - couldn't read '%s', " |
| "err = %d\n", proc_stat, errno); |
| goto out_close; |
| } |
| os_close_file(fd); |
| pc = ARBITRARY_ADDR; |
| if (sscanf(buf, "%*d " COMM_SCANF " %*c %*d %*d %*d %*d %*d %*d %*d " |
| "%*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d " |
| "%*d %*d %*d %*d %*d %lu", &pc) != 1) |
| printk(UM_KERN_ERR "os_process_pc - couldn't find pc in '%s'\n", |
| buf); |
| out_close: |
| close(fd); |
| out: |
| return pc; |
| } |
| |
| int os_process_parent(int pid) |
| { |
| char stat[STAT_PATH_LEN]; |
| char data[256]; |
| int parent = FAILURE_PID, n, fd; |
| |
| if (pid == -1) |
| return parent; |
| |
| snprintf(stat, sizeof(stat), "/proc/%d/stat", pid); |
| fd = open(stat, O_RDONLY, 0); |
| if (fd < 0) { |
| printk(UM_KERN_ERR "Couldn't open '%s', errno = %d\n", stat, |
| errno); |
| return parent; |
| } |
| |
| CATCH_EINTR(n = read(fd, data, sizeof(data))); |
| close(fd); |
| |
| if (n < 0) { |
| printk(UM_KERN_ERR "Couldn't read '%s', errno = %d\n", stat, |
| errno); |
| return parent; |
| } |
| |
| parent = FAILURE_PID; |
| n = sscanf(data, "%*d " COMM_SCANF " %*c %d", &parent); |
| if (n != 1) |
| printk(UM_KERN_ERR "Failed to scan '%s'\n", data); |
| |
| return parent; |
| } |
| |
| void os_stop_process(int pid) |
| { |
| kill(pid, SIGSTOP); |
| } |
| |
| void os_kill_process(int pid, int reap_child) |
| { |
| kill(pid, SIGKILL); |
| if (reap_child) |
| CATCH_EINTR(waitpid(pid, NULL, __WALL)); |
| } |
| |
| /* This is here uniquely to have access to the userspace errno, i.e. the one |
| * used by ptrace in case of error. |
| */ |
| |
| long os_ptrace_ldt(long pid, long addr, long data) |
| { |
| int ret; |
| |
| ret = ptrace(PTRACE_LDT, pid, addr, data); |
| |
| if (ret < 0) |
| return -errno; |
| return ret; |
| } |
| |
| /* Kill off a ptraced child by all means available. kill it normally first, |
| * then PTRACE_KILL it, then PTRACE_CONT it in case it's in a run state from |
| * which it can't exit directly. |
| */ |
| |
| void os_kill_ptraced_process(int pid, int reap_child) |
| { |
| kill(pid, SIGKILL); |
| ptrace(PTRACE_KILL, pid); |
| ptrace(PTRACE_CONT, pid); |
| if (reap_child) |
| CATCH_EINTR(waitpid(pid, NULL, __WALL)); |
| } |
| |
| /* Don't use the glibc version, which caches the result in TLS. It misses some |
| * syscalls, and also breaks with clone(), which does not unshare the TLS. |
| */ |
| |
| int os_getpid(void) |
| { |
| return syscall(__NR_getpid); |
| } |
| |
| int os_getpgrp(void) |
| { |
| return getpgrp(); |
| } |
| |
| int os_map_memory(void *virt, int fd, unsigned long long off, unsigned long len, |
| int r, int w, int x) |
| { |
| void *loc; |
| int prot; |
| |
| prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | |
| (x ? PROT_EXEC : 0); |
| |
| loc = mmap64((void *) virt, len, prot, MAP_SHARED | MAP_FIXED, |
| fd, off); |
| if (loc == MAP_FAILED) |
| return -errno; |
| return 0; |
| } |
| |
| int os_protect_memory(void *addr, unsigned long len, int r, int w, int x) |
| { |
| int prot = ((r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | |
| (x ? PROT_EXEC : 0)); |
| |
| if (mprotect(addr, len, prot) < 0) |
| return -errno; |
| |
| return 0; |
| } |
| |
| int os_unmap_memory(void *addr, int len) |
| { |
| int err; |
| |
| err = munmap(addr, len); |
| if (err < 0) |
| return -errno; |
| return 0; |
| } |
| |
| #ifndef MADV_REMOVE |
| #define MADV_REMOVE KERNEL_MADV_REMOVE |
| #endif |
| |
| int os_drop_memory(void *addr, int length) |
| { |
| int err; |
| |
| err = madvise(addr, length, MADV_REMOVE); |
| if (err < 0) |
| err = -errno; |
| return err; |
| } |
| |
| int __init can_drop_memory(void) |
| { |
| void *addr; |
| int fd, ok = 0; |
| |
| printk(UM_KERN_INFO "Checking host MADV_REMOVE support..."); |
| fd = create_mem_file(UM_KERN_PAGE_SIZE); |
| if (fd < 0) { |
| printk(UM_KERN_ERR "Creating test memory file failed, " |
| "err = %d\n", -fd); |
| goto out; |
| } |
| |
| addr = mmap64(NULL, UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE, |
| MAP_SHARED, fd, 0); |
| if (addr == MAP_FAILED) { |
| printk(UM_KERN_ERR "Mapping test memory file failed, " |
| "err = %d\n", -errno); |
| goto out_close; |
| } |
| |
| if (madvise(addr, UM_KERN_PAGE_SIZE, MADV_REMOVE) != 0) { |
| printk(UM_KERN_ERR "MADV_REMOVE failed, err = %d\n", -errno); |
| goto out_unmap; |
| } |
| |
| printk(UM_KERN_CONT "OK\n"); |
| ok = 1; |
| |
| out_unmap: |
| munmap(addr, UM_KERN_PAGE_SIZE); |
| out_close: |
| close(fd); |
| out: |
| return ok; |
| } |
| |
| static int os_page_mincore(void *addr) |
| { |
| char vec[2]; |
| int ret; |
| |
| ret = mincore(addr, UM_KERN_PAGE_SIZE, vec); |
| if (ret < 0) { |
| if (errno == ENOMEM || errno == EINVAL) |
| return 0; |
| else |
| return -errno; |
| } |
| |
| return vec[0] & 1; |
| } |
| |
| int os_mincore(void *addr, unsigned long len) |
| { |
| char *vec; |
| int ret, i; |
| |
| if (len <= UM_KERN_PAGE_SIZE) |
| return os_page_mincore(addr); |
| |
| vec = calloc(1, (len + UM_KERN_PAGE_SIZE - 1) / UM_KERN_PAGE_SIZE); |
| if (!vec) |
| return -ENOMEM; |
| |
| ret = mincore(addr, UM_KERN_PAGE_SIZE, vec); |
| if (ret < 0) { |
| if (errno == ENOMEM || errno == EINVAL) |
| ret = 0; |
| else |
| ret = -errno; |
| |
| goto out; |
| } |
| |
| for (i = 0; i < ((len + UM_KERN_PAGE_SIZE - 1) / UM_KERN_PAGE_SIZE); i++) { |
| if (!(vec[i] & 1)) { |
| ret = 0; |
| goto out; |
| } |
| } |
| |
| ret = 1; |
| out: |
| free(vec); |
| return ret; |
| } |
| |
| void init_new_thread_signals(void) |
| { |
| set_handler(SIGSEGV); |
| set_handler(SIGTRAP); |
| set_handler(SIGFPE); |
| set_handler(SIGILL); |
| set_handler(SIGBUS); |
| signal(SIGHUP, SIG_IGN); |
| set_handler(SIGIO); |
| signal(SIGWINCH, SIG_IGN); |
| signal(SIGTERM, SIG_DFL); |
| } |