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#ifndef __CR_ASM_RESTORER_H__
#define __CR_ASM_RESTORER_H__
#include "asm/types.h"
#include <compel/asm/fpu.h>
#include <compel/asm/infect-types.h>
#include "images/core.pb-c.h"
#include <compel/plugins/std/syscall-codes.h>
#include <compel/asm/sigframe.h>
#include "asm/compat.h"
#ifdef CONFIG_COMPAT
extern void restore_tls(tls_t *ptls);
extern int arch_compat_rt_sigaction(void *stack32, int sig, rt_sigaction_t_compat *act);
extern int set_compat_robust_list(uint32_t head_ptr, uint32_t len);
#else /* CONFIG_COMPAT */
static inline void restore_tls(tls_t *ptls)
{
}
static inline int arch_compat_rt_sigaction(void *stack, int sig, void *act)
{
return -1;
}
static inline int set_compat_robust_list(uint32_t head_ptr, uint32_t len)
{
return -1;
}
#endif /* !CONFIG_COMPAT */
/*
* Documentation copied from glibc sysdeps/unix/sysv/linux/x86_64/clone.S
* The kernel expects:
* rax: system call number
* rdi: flags
* rsi: child_stack
* rdx: TID field in parent
* r10: TID field in child
* r8: thread pointer
*
* int clone(unsigned long clone_flags, unsigned long newsp,
* int *parent_tidptr, int *child_tidptr,
* unsigned long tls);
*/
/* clang-format off */
#define RUN_CLONE_RESTORE_FN(ret, clone_flags, new_sp, parent_tid, \
thread_args, clone_restore_fn) \
asm volatile( \
"clone_emul: \n" \
"movq %2, %%rsi \n" \
"subq $16, %%rsi \n" \
"movq %6, %%rdi \n" \
"movq %%rdi, 8(%%rsi) \n" \
"movq %5, %%rdi \n" \
"movq %%rdi, 0(%%rsi) \n" \
"movq %1, %%rdi \n" \
"movq %3, %%rdx \n" \
"movq %4, %%r10 \n" \
"movl $"__stringify(__NR_clone)", %%eax \n" \
"syscall \n" \
\
"testq %%rax,%%rax \n" \
"jz thread_run \n" \
\
"movq %%rax, %0 \n" \
"jmp clone_end \n" \
\
"thread_run: \n" \
"xorq %%rbp, %%rbp \n" \
"popq %%rax \n" \
"popq %%rdi \n" \
"callq *%%rax \n" \
\
"clone_end: \n" \
: "=r"(ret) \
: "g"(clone_flags), \
"g"(new_sp), \
"g"(&parent_tid), \
"g"(&thread_args[i].pid), \
"g"(clone_restore_fn), \
"g"(&thread_args[i]) \
: "rax", "rcx", "rdi", "rsi", "rdx", "r10", "r11", "memory")
/* int clone3(struct clone_args *args, size_t size) */
#define RUN_CLONE3_RESTORE_FN(ret, clone_args, size, args, \
clone_restore_fn) \
asm volatile( \
"clone3_emul: \n" \
/*
* Prepare stack pointer for child process. The kernel does
* stack + stack_size before passing the stack pointer to the
* child process. As we have to put the function and the
* arguments for the new process on that stack we have handle
* the kernel's implicit stack + stack_size.
*/ \
"movq (%3), %%rsi /* new stack pointer */ \n" \
/* Move the stack_size to %rax to use later as the offset */ \
"movq %4, %%rax \n" \
/* 16 bytes are needed on the stack for function and args */ \
"subq $16, (%%rsi, %%rax) \n" \
"movq %6, %%rdi /* thread args */ \n" \
"movq %%rdi, 8(%%rsi, %%rax) \n" \
"movq %5, %%rdi /* thread function */ \n" \
"movq %%rdi, 0(%%rsi, %%rax) \n" \
/*
* The stack address has been modified for the two
* elements above (child function, child arguments).
* This modified stack needs to be stored back into the
* clone_args structure.
*/ \
"movq (%%rsi), %3 \n" \
/*
* Do the actual clone3() syscall. First argument (%rdi) is
* the clone_args structure, second argument is the size
* of clone_args.
*/ \
"movq %1, %%rdi /* clone_args */ \n" \
"movq %2, %%rsi /* size */ \n" \
"movl $"__stringify(__NR_clone3)", %%eax \n" \
"syscall \n" \
/*
* If clone3() was successful and if we are in the child
* '0' is returned. Jump to the child function handler.
*/ \
"testq %%rax,%%rax \n" \
"jz thread3_run \n" \
/* Return the PID to the parent process. */ \
"movq %%rax, %0 \n" \
"jmp clone3_end \n" \
\
"thread3_run: /* Child process */ \n" \
/* Clear the frame pointer */ \
"xorq %%rbp, %%rbp \n" \
/* Pop the child function from the stack */ \
"popq %%rax \n" \
/* Pop the child function arguments from the stack */ \
"popq %%rdi \n" \
/* Run the child function */ \
"callq *%%rax \n" \
/*
* If the child function is expected to return, this
* would be the place to handle the return code. In CRIU's
* case the child function is expected to not return
* and do exit() itself.
*/ \
\
"clone3_end: \n" \
: "=r"(ret) \
/*
* This uses the "r" modifier for all parameters
* as clang complained if using "g".
*/ \
: "r"(&clone_args), \
"r"(size), \
"r"(&clone_args.stack), \
"r"(clone_args.stack_size), \
"r"(clone_restore_fn), \
"r"(args) \
: "rax", "rcx", "rdi", "rsi", "rdx", "r10", "r11", "memory")
#define ARCH_FAIL_CORE_RESTORE \
asm volatile( \
"movq %0, %%rsp \n" \
"movq 0, %%rax \n" \
"jmp *%%rax \n" \
: \
: "r"(ret) \
: "memory")
/* clang-format on */
static inline void __setup_sas_compat(struct ucontext_ia32 *uc, ThreadSasEntry *sas)
{
uc->uc_stack.ss_sp = (compat_uptr_t)(sas)->ss_sp;
uc->uc_stack.ss_flags = (int)(sas)->ss_flags;
uc->uc_stack.ss_size = (compat_size_t)(sas)->ss_size;
}
static inline void __setup_sas(struct rt_sigframe *sigframe, ThreadSasEntry *sas)
{
if (sigframe->is_native) {
struct rt_ucontext *uc = &sigframe->native.uc;
uc->uc_stack.ss_sp = (void *)decode_pointer((sas)->ss_sp);
uc->uc_stack.ss_flags = (int)(sas)->ss_flags;
uc->uc_stack.ss_size = (size_t)(sas)->ss_size;
} else {
__setup_sas_compat(&sigframe->compat.uc, sas);
}
}
static inline void _setup_sas(struct rt_sigframe *sigframe, ThreadSasEntry *sas)
{
if (sas)
__setup_sas(sigframe, sas);
}
#define setup_sas _setup_sas
int restore_gpregs(struct rt_sigframe *f, UserX86RegsEntry *r);
int restore_nonsigframe_gpregs(UserX86RegsEntry *r);
int ptrace_set_breakpoint(pid_t pid, void *addr);
int ptrace_flush_breakpoints(pid_t pid);
extern int arch_map_vdso(unsigned long map_at, bool compatible);
#endif
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