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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2021 Benjamin Berg <benjamin@sipsolutions.net>
*/
#include <sysdep/stub.h>
static __always_inline int syscall_handler(struct stub_data *d)
{
int i;
unsigned long res;
for (i = 0; i < d->syscall_data_len; i++) {
struct stub_syscall *sc = &d->syscall_data[i];
switch (sc->syscall) {
case STUB_SYSCALL_MMAP:
res = stub_syscall6(STUB_MMAP_NR,
sc->mem.addr, sc->mem.length,
sc->mem.prot,
MAP_SHARED | MAP_FIXED,
sc->mem.fd, sc->mem.offset);
if (res != sc->mem.addr) {
d->err = res;
d->syscall_data_len = i;
return -1;
}
break;
case STUB_SYSCALL_MUNMAP:
res = stub_syscall2(__NR_munmap,
sc->mem.addr, sc->mem.length);
if (res) {
d->err = res;
d->syscall_data_len = i;
return -1;
}
break;
case STUB_SYSCALL_MPROTECT:
res = stub_syscall3(__NR_mprotect,
sc->mem.addr, sc->mem.length,
sc->mem.prot);
if (res) {
d->err = res;
d->syscall_data_len = i;
return -1;
}
break;
case STUB_SYSCALL_LDT:
res = stub_syscall3(__NR_modify_ldt, sc->ldt.func,
(unsigned long) &sc->ldt.desc,
sizeof(sc->ldt.desc));
/* We only write, so the expected result is zero */
if (res) {
d->err = res;
d->syscall_data_len = i;
return -1;
}
break;
default:
d->err = -95; /* EOPNOTSUPP */
d->syscall_data_len = i;
return -1;
}
}
d->err = 0;
d->syscall_data_len = 0;
return 0;
}
void __section(".__syscall_stub")
stub_syscall_handler(void)
{
struct stub_data *d = get_stub_data();
syscall_handler(d);
trap_myself();
}
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