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; 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 panic("do_syscall_stub : PTRACE_SETREGS failed, errno = %d\n", 71 n); 72 73 wait_stub_done(pid, 0, "do_syscall_stub"); 74 75 /* When the stub stops, we find the following values on the 76 * beginning of the stack: 77 * (long )return_value 78 * (long )offset to failed sycall-data (0, if no error) 79 */ 80 ret = *((unsigned long *) mm_idp->stack); 81 offset = *((unsigned long *) mm_idp->stack + 1); 82 if (offset) { 83 data = (unsigned long *)(mm_idp->stack + 84 offset - UML_CONFIG_STUB_DATA); 85 printk("do_syscall_stub : ret = %ld, offset = %ld, " 86 "data = %p\n", ret, offset, data); 87 syscall = (unsigned long *)((unsigned long)data + data[0]); 88 printk("do_syscall_stub: syscall %ld failed, return value = " 89 "0x%lx, expected return value = 0x%lx\n", 90 syscall[0], ret, syscall[7]); 91 printk(" syscall parameters: " 92 "0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", 93 syscall[1], syscall[2], syscall[3], 94 syscall[4], syscall[5], syscall[6]); 95 for(n = 1; n < data[0]/sizeof(long); n++) { 96 if(n == 1) 97 printk(" additional syscall data:"); 98 if(n % 4 == 1) 99 printk("\n "); 100 printk(" 0x%lx", data[n]); 101 } 102 if(n > 1) 103 printk("\n"); 104 } 105 else ret = 0; 106 107 *addr = check_init_stack(mm_idp, NULL); 108 109 return ret; 110 } 111 112 long run_syscall_stub(struct mm_id * mm_idp, int syscall, 113 unsigned long *args, long expected, void **addr, 114 int done) 115 { 116 unsigned long *stack = check_init_stack(mm_idp, *addr); 117 118 if(done && *addr == NULL) 119 single_count++; 120 121 *stack += sizeof(long); 122 stack += *stack / sizeof(long); 123 124 *stack++ = syscall; 125 *stack++ = args[0]; 126 *stack++ = args[1]; 127 *stack++ = args[2]; 128 *stack++ = args[3]; 129 *stack++ = args[4]; 130 *stack++ = args[5]; 131 *stack++ = expected; 132 *stack = 0; 133 multi_op_count++; 134 135 if(!done && ((((unsigned long) stack) & ~PAGE_MASK) < 136 PAGE_SIZE - 10 * sizeof(long))){ 137 *addr = stack; 138 return 0; 139 } 140 141 return do_syscall_stub(mm_idp, addr); 142 } 143 144 long syscall_stub_data(struct mm_id * mm_idp, 145 unsigned long *data, int data_count, 146 void **addr, void **stub_addr) 147 { 148 unsigned long *stack; 149 int ret = 0; 150 151 /* If *addr still is uninitialized, it *must* contain NULL. 152 * Thus in this case do_syscall_stub correctly won't be called. 153 */ 154 if((((unsigned long) *addr) & ~PAGE_MASK) >= 155 PAGE_SIZE - (10 + data_count) * sizeof(long)) { 156 ret = do_syscall_stub(mm_idp, addr); 157 /* in case of error, don't overwrite data on stack */ 158 if(ret) 159 return ret; 160 } 161 162 stack = check_init_stack(mm_idp, *addr); 163 *addr = stack; 164 165 *stack = data_count * sizeof(long); 166 167 memcpy(stack + 1, data, data_count * sizeof(long)); 168 169 *stub_addr = (void *)(((unsigned long)(stack + 1) & ~PAGE_MASK) + 170 UML_CONFIG_STUB_DATA); 171 172 return 0; 173 } 174 175 int map(struct mm_id * mm_idp, unsigned long virt, unsigned long len, 176 int r, int w, int x, int phys_fd, unsigned long long offset, 177 int done, void **data) 178 { 179 int prot, ret; 180 181 prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 182 (x ? PROT_EXEC : 0); 183 184 if(proc_mm){ 185 struct proc_mm_op map; 186 int fd = mm_idp->u.mm_fd; 187 188 map = ((struct proc_mm_op) { .op = MM_MMAP, 189 .u = 190 { .mmap = 191 { .addr = virt, 192 .len = len, 193 .prot = prot, 194 .flags = MAP_SHARED | 195 MAP_FIXED, 196 .fd = phys_fd, 197 .offset= offset 198 } } } ); 199 ret = os_write_file(fd, &map, sizeof(map)); 200 if(ret != sizeof(map)) 201 printk("map : /proc/mm map failed, err = %d\n", -ret); 202 else ret = 0; 203 } 204 else { 205 unsigned long args[] = { virt, len, prot, 206 MAP_SHARED | MAP_FIXED, phys_fd, 207 MMAP_OFFSET(offset) }; 208 209 ret = run_syscall_stub(mm_idp, STUB_MMAP_NR, args, virt, 210 data, done); 211 } 212 213 return ret; 214 } 215 216 int unmap(struct mm_id * mm_idp, void *addr, unsigned long len, int done, 217 void **data) 218 { 219 int ret; 220 221 if(proc_mm){ 222 struct proc_mm_op unmap; 223 int fd = mm_idp->u.mm_fd; 224 225 unmap = ((struct proc_mm_op) { .op = MM_MUNMAP, 226 .u = 227 { .munmap = 228 { .addr = 229 (unsigned long) addr, 230 .len = len } } } ); 231 ret = os_write_file(fd, &unmap, sizeof(unmap)); 232 if(ret != sizeof(unmap)) 233 printk("unmap - proc_mm write returned %d\n", ret); 234 else ret = 0; 235 } 236 else { 237 unsigned long args[] = { (unsigned long) addr, len, 0, 0, 0, 238 0 }; 239 240 ret = run_syscall_stub(mm_idp, __NR_munmap, args, 0, 241 data, done); 242 } 243 244 return ret; 245 } 246 247 int protect(struct mm_id * mm_idp, unsigned long addr, unsigned long len, 248 int r, int w, int x, int done, void **data) 249 { 250 struct proc_mm_op protect; 251 int prot, ret; 252 253 prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 254 (x ? PROT_EXEC : 0); 255 if(proc_mm){ 256 int fd = mm_idp->u.mm_fd; 257 258 protect = ((struct proc_mm_op) { .op = MM_MPROTECT, 259 .u = 260 { .mprotect = 261 { .addr = 262 (unsigned long) addr, 263 .len = len, 264 .prot = prot } } } ); 265 266 ret = os_write_file(fd, &protect, sizeof(protect)); 267 if(ret != sizeof(protect)) 268 printk("protect failed, err = %d", -ret); 269 else ret = 0; 270 } 271 else { 272 unsigned long args[] = { addr, len, prot, 0, 0, 0 }; 273 274 ret = run_syscall_stub(mm_idp, __NR_mprotect, args, 0, 275 data, done); 276 } 277 278 return ret; 279 } 280 281 void before_mem_skas(unsigned long unused) 282 { 283 } 284