1 /* 2 * Copyright (C) 2002 Jeff Dike (jdike@karaya.com) 3 * Licensed under the GPL 4 */ 5 6 #include <signal.h> 7 #include <errno.h> 8 #include <string.h> 9 #include <sys/mman.h> 10 #include <sys/wait.h> 11 #include <asm/page.h> 12 #include <asm/unistd.h> 13 #include "mem_user.h" 14 #include "mem.h" 15 #include "skas.h" 16 #include "user.h" 17 #include "os.h" 18 #include "proc_mm.h" 19 #include "ptrace_user.h" 20 #include "user_util.h" 21 #include "kern_util.h" 22 #include "task.h" 23 #include "registers.h" 24 #include "uml-config.h" 25 #include "sysdep/ptrace.h" 26 #include "sysdep/stub.h" 27 28 extern unsigned long batch_syscall_stub, __syscall_stub_start; 29 30 extern void wait_stub_done(int pid, int sig, char * fname); 31 32 static inline unsigned long *check_init_stack(struct mm_id * mm_idp, 33 unsigned long *stack) 34 { 35 if(stack == NULL) { 36 stack = (unsigned long *) mm_idp->stack + 2; 37 *stack = 0; 38 } 39 return stack; 40 } 41 42 extern int proc_mm; 43 44 int single_count = 0; 45 int multi_count = 0; 46 int multi_op_count = 0; 47 48 static inline long do_syscall_stub(struct mm_id * mm_idp, void **addr) 49 { 50 unsigned long regs[MAX_REG_NR]; 51 int n, i; 52 long ret, offset; 53 unsigned long * data; 54 unsigned long * syscall; 55 int pid = mm_idp->u.pid; 56 57 if(proc_mm) 58 #warning Need to look up userspace_pid by cpu 59 pid = userspace_pid[0]; 60 61 multi_count++; 62 63 get_safe_registers(regs, NULL); 64 regs[REGS_IP_INDEX] = UML_CONFIG_STUB_CODE + 65 ((unsigned long) &batch_syscall_stub - 66 (unsigned long) &__syscall_stub_start); 67 68 n = ptrace_setregs(pid, regs); 69 if(n < 0){ 70 printk("Registers - \n"); 71 for(i = 0; i < MAX_REG_NR; i++) 72 printk("\t%d\t0x%lx\n", i, regs[i]); 73 panic("do_syscall_stub : PTRACE_SETREGS failed, errno = %d\n", 74 -n); 75 } 76 77 wait_stub_done(pid, 0, "do_syscall_stub"); 78 79 /* When the stub stops, we find the following values on the 80 * beginning of the stack: 81 * (long )return_value 82 * (long )offset to failed sycall-data (0, if no error) 83 */ 84 ret = *((unsigned long *) mm_idp->stack); 85 offset = *((unsigned long *) mm_idp->stack + 1); 86 if (offset) { 87 data = (unsigned long *)(mm_idp->stack + 88 offset - UML_CONFIG_STUB_DATA); 89 printk("do_syscall_stub : ret = %ld, offset = %ld, " 90 "data = %p\n", ret, offset, data); 91 syscall = (unsigned long *)((unsigned long)data + data[0]); 92 printk("do_syscall_stub: syscall %ld failed, return value = " 93 "0x%lx, expected return value = 0x%lx\n", 94 syscall[0], ret, syscall[7]); 95 printk(" syscall parameters: " 96 "0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", 97 syscall[1], syscall[2], syscall[3], 98 syscall[4], syscall[5], syscall[6]); 99 for(n = 1; n < data[0]/sizeof(long); n++) { 100 if(n == 1) 101 printk(" additional syscall data:"); 102 if(n % 4 == 1) 103 printk("\n "); 104 printk(" 0x%lx", data[n]); 105 } 106 if(n > 1) 107 printk("\n"); 108 } 109 else ret = 0; 110 111 *addr = check_init_stack(mm_idp, NULL); 112 113 return ret; 114 } 115 116 long run_syscall_stub(struct mm_id * mm_idp, int syscall, 117 unsigned long *args, long expected, void **addr, 118 int done) 119 { 120 unsigned long *stack = check_init_stack(mm_idp, *addr); 121 122 if(done && *addr == NULL) 123 single_count++; 124 125 *stack += sizeof(long); 126 stack += *stack / sizeof(long); 127 128 *stack++ = syscall; 129 *stack++ = args[0]; 130 *stack++ = args[1]; 131 *stack++ = args[2]; 132 *stack++ = args[3]; 133 *stack++ = args[4]; 134 *stack++ = args[5]; 135 *stack++ = expected; 136 *stack = 0; 137 multi_op_count++; 138 139 if(!done && ((((unsigned long) stack) & ~PAGE_MASK) < 140 PAGE_SIZE - 10 * sizeof(long))){ 141 *addr = stack; 142 return 0; 143 } 144 145 return do_syscall_stub(mm_idp, addr); 146 } 147 148 long syscall_stub_data(struct mm_id * mm_idp, 149 unsigned long *data, int data_count, 150 void **addr, void **stub_addr) 151 { 152 unsigned long *stack; 153 int ret = 0; 154 155 /* If *addr still is uninitialized, it *must* contain NULL. 156 * Thus in this case do_syscall_stub correctly won't be called. 157 */ 158 if((((unsigned long) *addr) & ~PAGE_MASK) >= 159 PAGE_SIZE - (10 + data_count) * sizeof(long)) { 160 ret = do_syscall_stub(mm_idp, addr); 161 /* in case of error, don't overwrite data on stack */ 162 if(ret) 163 return ret; 164 } 165 166 stack = check_init_stack(mm_idp, *addr); 167 *addr = stack; 168 169 *stack = data_count * sizeof(long); 170 171 memcpy(stack + 1, data, data_count * sizeof(long)); 172 173 *stub_addr = (void *)(((unsigned long)(stack + 1) & ~PAGE_MASK) + 174 UML_CONFIG_STUB_DATA); 175 176 return 0; 177 } 178 179 int map(struct mm_id * mm_idp, unsigned long virt, unsigned long len, 180 int r, int w, int x, int phys_fd, unsigned long long offset, 181 int done, void **data) 182 { 183 int prot, ret; 184 185 prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 186 (x ? PROT_EXEC : 0); 187 188 if(proc_mm){ 189 struct proc_mm_op map; 190 int fd = mm_idp->u.mm_fd; 191 192 map = ((struct proc_mm_op) { .op = MM_MMAP, 193 .u = 194 { .mmap = 195 { .addr = virt, 196 .len = len, 197 .prot = prot, 198 .flags = MAP_SHARED | 199 MAP_FIXED, 200 .fd = phys_fd, 201 .offset= offset 202 } } } ); 203 ret = os_write_file(fd, &map, sizeof(map)); 204 if(ret != sizeof(map)) 205 printk("map : /proc/mm map failed, err = %d\n", -ret); 206 else ret = 0; 207 } 208 else { 209 unsigned long args[] = { virt, len, prot, 210 MAP_SHARED | MAP_FIXED, phys_fd, 211 MMAP_OFFSET(offset) }; 212 213 ret = run_syscall_stub(mm_idp, STUB_MMAP_NR, args, virt, 214 data, done); 215 } 216 217 return ret; 218 } 219 220 int unmap(struct mm_id * mm_idp, void *addr, unsigned long len, int done, 221 void **data) 222 { 223 int ret; 224 225 if(proc_mm){ 226 struct proc_mm_op unmap; 227 int fd = mm_idp->u.mm_fd; 228 229 unmap = ((struct proc_mm_op) { .op = MM_MUNMAP, 230 .u = 231 { .munmap = 232 { .addr = 233 (unsigned long) addr, 234 .len = len } } } ); 235 ret = os_write_file(fd, &unmap, sizeof(unmap)); 236 if(ret != sizeof(unmap)) 237 printk("unmap - proc_mm write returned %d\n", ret); 238 else ret = 0; 239 } 240 else { 241 unsigned long args[] = { (unsigned long) addr, len, 0, 0, 0, 242 0 }; 243 244 ret = run_syscall_stub(mm_idp, __NR_munmap, args, 0, 245 data, done); 246 } 247 248 return ret; 249 } 250 251 int protect(struct mm_id * mm_idp, unsigned long addr, unsigned long len, 252 int r, int w, int x, int done, void **data) 253 { 254 struct proc_mm_op protect; 255 int prot, ret; 256 257 prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 258 (x ? PROT_EXEC : 0); 259 if(proc_mm){ 260 int fd = mm_idp->u.mm_fd; 261 262 protect = ((struct proc_mm_op) { .op = MM_MPROTECT, 263 .u = 264 { .mprotect = 265 { .addr = 266 (unsigned long) addr, 267 .len = len, 268 .prot = prot } } } ); 269 270 ret = os_write_file(fd, &protect, sizeof(protect)); 271 if(ret != sizeof(protect)) 272 printk("protect failed, err = %d", -ret); 273 else ret = 0; 274 } 275 else { 276 unsigned long args[] = { addr, len, prot, 0, 0, 0 }; 277 278 ret = run_syscall_stub(mm_idp, __NR_mprotect, args, 0, 279 data, done); 280 } 281 282 return ret; 283 } 284 285 void before_mem_skas(unsigned long unused) 286 { 287 } 288