sys32.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * arch/arm64/kernel/sys32.c
  4 *
  5 * Copyright (C) 2015 ARM Ltd.
  6 */
  7
  8#include <linux/compat.h>
  9#include <linux/compiler.h>
 10#include <linux/syscalls.h>
 11
 12#include <asm/syscall.h>
 13#include <asm/unistd_compat_32.h>
 14
 15asmlinkage long compat_sys_sigreturn(void);
 16asmlinkage long compat_sys_rt_sigreturn(void);
 17
 18COMPAT_SYSCALL_DEFINE3(aarch32_statfs64, const char __user *, pathname,
 19		       compat_size_t, sz, struct compat_statfs64 __user *, buf)
 20{
 21	/*
 22	 * 32-bit ARM applies an OABI compatibility fixup to statfs64 and
 23	 * fstatfs64 regardless of whether OABI is in use, and therefore
 24	 * arbitrary binaries may rely upon it, so we must do the same.
 25	 * For more details, see commit:
 26	 *
 27	 * 713c481519f19df9 ("[ARM] 3108/2: old ABI compat: statfs64 and
 28	 * fstatfs64")
 29	 */
 30	if (sz == 88)
 31		sz = 84;
 32
 33	return kcompat_sys_statfs64(pathname, sz, buf);
 34}
 35
 36COMPAT_SYSCALL_DEFINE3(aarch32_fstatfs64, unsigned int, fd, compat_size_t, sz,
 37		       struct compat_statfs64 __user *, buf)
 38{
 39	/* see aarch32_statfs64 */
 40	if (sz == 88)
 41		sz = 84;
 42
 43	return kcompat_sys_fstatfs64(fd, sz, buf);
 44}
 45
 46/*
 47 * Note: off_4k is always in units of 4K. If we can't do the
 48 * requested offset because it is not page-aligned, we return -EINVAL.
 49 */
 50COMPAT_SYSCALL_DEFINE6(aarch32_mmap2, unsigned long, addr, unsigned long, len,
 51		       unsigned long, prot, unsigned long, flags,
 52		       unsigned long, fd, unsigned long, off_4k)
 53{
 54	if (off_4k & (~PAGE_MASK >> 12))
 55		return -EINVAL;
 56
 57	off_4k >>= (PAGE_SHIFT - 12);
 58
 59	return ksys_mmap_pgoff(addr, len, prot, flags, fd, off_4k);
 60}
 61
 62#ifdef CONFIG_CPU_BIG_ENDIAN
 63#define arg_u32p(name)	u32, name##_hi, u32, name##_lo
 64#else
 65#define arg_u32p(name)	u32, name##_lo, u32, name##_hi
 66#endif
 67
 68#define arg_u64(name)	(((u64)name##_hi << 32) | name##_lo)
 69
 70COMPAT_SYSCALL_DEFINE6(aarch32_pread64, unsigned int, fd, char __user *, buf,
 71		       size_t, count, u32, __pad, arg_u32p(pos))
 72{
 73	return ksys_pread64(fd, buf, count, arg_u64(pos));
 74}
 75
 76COMPAT_SYSCALL_DEFINE6(aarch32_pwrite64, unsigned int, fd,
 77		       const char __user *, buf, size_t, count, u32, __pad,
 78		       arg_u32p(pos))
 79{
 80	return ksys_pwrite64(fd, buf, count, arg_u64(pos));
 81}
 82
 83COMPAT_SYSCALL_DEFINE4(aarch32_truncate64, const char __user *, pathname,
 84		       u32, __pad, arg_u32p(length))
 85{
 86	return ksys_truncate(pathname, arg_u64(length));
 87}
 88
 89COMPAT_SYSCALL_DEFINE4(aarch32_ftruncate64, unsigned int, fd, u32, __pad,
 90		       arg_u32p(length))
 91{
 92	return ksys_ftruncate(fd, arg_u64(length));
 93}
 94
 95COMPAT_SYSCALL_DEFINE5(aarch32_readahead, int, fd, u32, __pad,
 96		       arg_u32p(offset), size_t, count)
 97{
 98	return ksys_readahead(fd, arg_u64(offset), count);
 99}
100
101COMPAT_SYSCALL_DEFINE6(aarch32_fadvise64_64, int, fd, int, advice,
102		       arg_u32p(offset), arg_u32p(len))
103{
104	return ksys_fadvise64_64(fd, arg_u64(offset), arg_u64(len), advice);
105}
106
107COMPAT_SYSCALL_DEFINE6(aarch32_sync_file_range2, int, fd, unsigned int, flags,
108		       arg_u32p(offset), arg_u32p(nbytes))
109{
110	return ksys_sync_file_range(fd, arg_u64(offset), arg_u64(nbytes),
111				    flags);
112}
113
114COMPAT_SYSCALL_DEFINE6(aarch32_fallocate, int, fd, int, mode,
115		       arg_u32p(offset), arg_u32p(len))
116{
117	return ksys_fallocate(fd, mode, arg_u64(offset), arg_u64(len));
118}
119
120#define __SYSCALL_WITH_COMPAT(nr, sym, compat) __SYSCALL(nr, compat)
121
122#undef __SYSCALL
123#define __SYSCALL(nr, sym)	asmlinkage long __arm64_##sym(const struct pt_regs *);
124#include <asm/syscall_table_32.h>
125
126#undef __SYSCALL
127#define __SYSCALL(nr, sym)	[nr] = __arm64_##sym,
128
129const syscall_fn_t compat_sys_call_table[__NR_compat32_syscalls] = {
130	[0 ... __NR_compat32_syscalls - 1] = __arm64_sys_ni_syscall,
131#include <asm/syscall_table_32.h>
132};