Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 | // SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) */ #include <stddef.h> #include <unistd.h> #include <errno.h> #include <string.h> #include <sys/mman.h> #include <init.h> #include <as-layout.h> #include <mm_id.h> #include <os.h> #include <ptrace_user.h> #include <registers.h> #include <skas.h> #include <sysdep/ptrace.h> #include <sysdep/stub.h> extern char batch_syscall_stub[], __syscall_stub_start[]; extern void wait_stub_done(int pid); static inline unsigned long *check_init_stack(struct mm_id * mm_idp, unsigned long *stack) { if (stack == NULL) { stack = (unsigned long *) mm_idp->stack + 2; *stack = 0; } return stack; } static unsigned long syscall_regs[MAX_REG_NR]; static int __init init_syscall_regs(void) { get_safe_registers(syscall_regs, NULL); syscall_regs[REGS_IP_INDEX] = STUB_CODE + ((unsigned long) batch_syscall_stub - (unsigned long) __syscall_stub_start); syscall_regs[REGS_SP_INDEX] = STUB_DATA; return 0; } __initcall(init_syscall_regs); static inline long do_syscall_stub(struct mm_id * mm_idp, void **addr) { int n, i; long ret, offset; unsigned long * data; unsigned long * syscall; int err, pid = mm_idp->u.pid; n = ptrace_setregs(pid, syscall_regs); if (n < 0) { printk(UM_KERN_ERR "Registers - \n"); for (i = 0; i < MAX_REG_NR; i++) printk(UM_KERN_ERR "\t%d\t0x%lx\n", i, syscall_regs[i]); panic("do_syscall_stub : PTRACE_SETREGS failed, errno = %d\n", -n); } err = ptrace(PTRACE_CONT, pid, 0, 0); if (err) panic("Failed to continue stub, pid = %d, errno = %d\n", pid, errno); wait_stub_done(pid); /* * When the stub stops, we find the following values on the * beginning of the stack: * (long )return_value * (long )offset to failed sycall-data (0, if no error) */ ret = *((unsigned long *) mm_idp->stack); offset = *((unsigned long *) mm_idp->stack + 1); if (offset) { data = (unsigned long *)(mm_idp->stack + offset - STUB_DATA); printk(UM_KERN_ERR "do_syscall_stub : ret = %ld, offset = %ld, " "data = %p\n", ret, offset, data); syscall = (unsigned long *)((unsigned long)data + data[0]); printk(UM_KERN_ERR "do_syscall_stub: syscall %ld failed, " "return value = 0x%lx, expected return value = 0x%lx\n", syscall[0], ret, syscall[7]); printk(UM_KERN_ERR " syscall parameters: " "0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", syscall[1], syscall[2], syscall[3], syscall[4], syscall[5], syscall[6]); for (n = 1; n < data[0]/sizeof(long); n++) { if (n == 1) printk(UM_KERN_ERR " additional syscall " "data:"); if (n % 4 == 1) printk("\n" UM_KERN_ERR " "); printk(" 0x%lx", data[n]); } if (n > 1) printk("\n"); } else ret = 0; *addr = check_init_stack(mm_idp, NULL); return ret; } long run_syscall_stub(struct mm_id * mm_idp, int syscall, unsigned long *args, long expected, void **addr, int done) { unsigned long *stack = check_init_stack(mm_idp, *addr); *stack += sizeof(long); stack += *stack / sizeof(long); *stack++ = syscall; *stack++ = args[0]; *stack++ = args[1]; *stack++ = args[2]; *stack++ = args[3]; *stack++ = args[4]; *stack++ = args[5]; *stack++ = expected; *stack = 0; if (!done && ((((unsigned long) stack) & ~UM_KERN_PAGE_MASK) < UM_KERN_PAGE_SIZE - 10 * sizeof(long))) { *addr = stack; return 0; } return do_syscall_stub(mm_idp, addr); } long syscall_stub_data(struct mm_id * mm_idp, unsigned long *data, int data_count, void **addr, void **stub_addr) { unsigned long *stack; int ret = 0; /* * If *addr still is uninitialized, it *must* contain NULL. * Thus in this case do_syscall_stub correctly won't be called. */ if ((((unsigned long) *addr) & ~UM_KERN_PAGE_MASK) >= UM_KERN_PAGE_SIZE - (10 + data_count) * sizeof(long)) { ret = do_syscall_stub(mm_idp, addr); /* in case of error, don't overwrite data on stack */ if (ret) return ret; } stack = check_init_stack(mm_idp, *addr); *addr = stack; *stack = data_count * sizeof(long); memcpy(stack + 1, data, data_count * sizeof(long)); *stub_addr = (void *)(((unsigned long)(stack + 1) & ~UM_KERN_PAGE_MASK) + STUB_DATA); return 0; } int map(struct mm_id * mm_idp, unsigned long virt, unsigned long len, int prot, int phys_fd, unsigned long long offset, int done, void **data) { int ret; unsigned long args[] = { virt, len, prot, MAP_SHARED | MAP_FIXED, phys_fd, MMAP_OFFSET(offset) }; ret = run_syscall_stub(mm_idp, STUB_MMAP_NR, args, virt, data, done); return ret; } int unmap(struct mm_id * mm_idp, unsigned long addr, unsigned long len, int done, void **data) { int ret; unsigned long args[] = { (unsigned long) addr, len, 0, 0, 0, 0 }; ret = run_syscall_stub(mm_idp, __NR_munmap, args, 0, data, done); return ret; } int protect(struct mm_id * mm_idp, unsigned long addr, unsigned long len, unsigned int prot, int done, void **data) { int ret; unsigned long args[] = { addr, len, prot, 0, 0, 0 }; ret = run_syscall_stub(mm_idp, __NR_mprotect, args, 0, data, done); return ret; } |