1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
12 #include <as-layout.h>
15 #include <ptrace_user.h>
16 #include <registers.h>
18 #include <sysdep/ptrace.h>
19 #include <sysdep/stub.h>
21 extern char batch_syscall_stub[], __syscall_stub_start[];
23 extern void wait_stub_done(int pid);
25 static inline unsigned long *check_init_stack(struct mm_id * mm_idp,
29 stack = (unsigned long *) mm_idp->stack + 2;
35 static unsigned long syscall_regs[MAX_REG_NR];
37 static int __init init_syscall_regs(void)
39 get_safe_registers(syscall_regs, NULL);
40 syscall_regs[REGS_IP_INDEX] = STUB_CODE +
41 ((unsigned long) batch_syscall_stub -
42 (unsigned long) __syscall_stub_start);
43 syscall_regs[REGS_SP_INDEX] = STUB_DATA;
48 __initcall(init_syscall_regs);
50 static inline long do_syscall_stub(struct mm_id * mm_idp, void **addr)
55 unsigned long * syscall;
56 int err, pid = mm_idp->u.pid;
58 n = ptrace_setregs(pid, syscall_regs);
60 printk(UM_KERN_ERR "Registers - \n");
61 for (i = 0; i < MAX_REG_NR; i++)
62 printk(UM_KERN_ERR "\t%d\t0x%lx\n", i, syscall_regs[i]);
63 panic("do_syscall_stub : PTRACE_SETREGS failed, errno = %d\n",
67 err = ptrace(PTRACE_CONT, pid, 0, 0);
69 panic("Failed to continue stub, pid = %d, errno = %d\n", pid,
75 * When the stub stops, we find the following values on the
76 * beginning of the stack:
78 * (long )offset to failed sycall-data (0, if no error)
80 ret = *((unsigned long *) mm_idp->stack);
81 offset = *((unsigned long *) mm_idp->stack + 1);
83 data = (unsigned long *)(mm_idp->stack + offset - STUB_DATA);
84 printk(UM_KERN_ERR "do_syscall_stub : ret = %ld, offset = %ld, "
85 "data = %p\n", ret, offset, data);
86 syscall = (unsigned long *)((unsigned long)data + data[0]);
87 printk(UM_KERN_ERR "do_syscall_stub: syscall %ld failed, "
88 "return value = 0x%lx, expected return value = 0x%lx\n",
89 syscall[0], ret, syscall[7]);
90 printk(UM_KERN_ERR " syscall parameters: "
91 "0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n",
92 syscall[1], syscall[2], syscall[3],
93 syscall[4], syscall[5], syscall[6]);
94 for (n = 1; n < data[0]/sizeof(long); n++) {
96 printk(UM_KERN_ERR " additional syscall "
99 printk("\n" UM_KERN_ERR " ");
100 printk(" 0x%lx", data[n]);
107 *addr = check_init_stack(mm_idp, NULL);
112 long run_syscall_stub(struct mm_id * mm_idp, int syscall,
113 unsigned long *args, long expected, void **addr,
116 unsigned long *stack = check_init_stack(mm_idp, *addr);
118 *stack += sizeof(long);
119 stack += *stack / sizeof(long);
131 if (!done && ((((unsigned long) stack) & ~UM_KERN_PAGE_MASK) <
132 UM_KERN_PAGE_SIZE - 10 * sizeof(long))) {
137 return do_syscall_stub(mm_idp, addr);
140 long syscall_stub_data(struct mm_id * mm_idp,
141 unsigned long *data, int data_count,
142 void **addr, void **stub_addr)
144 unsigned long *stack;
148 * If *addr still is uninitialized, it *must* contain NULL.
149 * Thus in this case do_syscall_stub correctly won't be called.
151 if ((((unsigned long) *addr) & ~UM_KERN_PAGE_MASK) >=
152 UM_KERN_PAGE_SIZE - (10 + data_count) * sizeof(long)) {
153 ret = do_syscall_stub(mm_idp, addr);
154 /* in case of error, don't overwrite data on stack */
159 stack = check_init_stack(mm_idp, *addr);
162 *stack = data_count * sizeof(long);
164 memcpy(stack + 1, data, data_count * sizeof(long));
166 *stub_addr = (void *)(((unsigned long)(stack + 1) &
167 ~UM_KERN_PAGE_MASK) + STUB_DATA);
172 int map(struct mm_id * mm_idp, unsigned long virt, unsigned long len, int prot,
173 int phys_fd, unsigned long long offset, int done, void **data)
176 unsigned long args[] = { virt, len, prot,
177 MAP_SHARED | MAP_FIXED, phys_fd,
178 MMAP_OFFSET(offset) };
180 ret = run_syscall_stub(mm_idp, STUB_MMAP_NR, args, virt,
186 int unmap(struct mm_id * mm_idp, unsigned long addr, unsigned long len,
187 int done, void **data)
190 unsigned long args[] = { (unsigned long) addr, len, 0, 0, 0,
193 ret = run_syscall_stub(mm_idp, __NR_munmap, args, 0,
199 int protect(struct mm_id * mm_idp, unsigned long addr, unsigned long len,
200 unsigned int prot, int done, void **data)
203 unsigned long args[] = { addr, len, prot, 0, 0, 0 };
205 ret = run_syscall_stub(mm_idp, __NR_mprotect, args, 0,