* exec/config-mips.m4.in (DADDI2, DADDI3): Disable at-clobbering
by assembler macros expressly.
* exec/loader-mips64el.s: Adapt from loader-mipsel.s.
* exec/configure.ac (exec_cv_as_daddi): Properly escape reg
names.
* exec/exec.c (struct exec_jump_command, exec_0): Don't define
or set `fpu_mode' if __LP64__.
* exec/exec.h (struct exec_tracee): New field `callno'.
* exec/trace.c (process_system_call): Always record the current
system call number in TRACEE lest it should be required once it
has been overwritten upon the syscall's completion.
(seccomp_system_call): Likewise.
(after_fork): Clear `tracee->callno'.
* exec/exec.c (insert_args, exec_0): On non-MIPS systems, copy
NAME and its length to the loader area. State that MIPS support
is not yet available (though it will be pending the availability
of a functioning emulator).
* exec/loader-aarch64.s (_start):
* exec/loader-armeabi.s (_start):
* exec/loader-x86.s (_start):
* exec/loader-x86_64.s (_start): Displace auxv, environ, and
argv to create sufficient space for the provided file name, and
copy the file name there. Replace AT_EXECFN to refer to this
space.
* exec/trace.c (process_vm_readv, process_vm_writev): New
function pointers. Attempt to load them on recent Android
systems when `exec' was not linked with a sufficiently
up-to-date libc.
(read_memory, user_copy): Always use process_vm_readv and
process_vm_writev if available.
(handle_openat): Write trailing NULL byte of filename to user
buffer.
(exec_init): Attempt to dlsym process_vm_readv and
process_vm_writev.
* etc/NEWS: Update correspondingly.
* exec/Makefile.in (config-mips.m4): Don't define rule
or predicate $(LOADOBJS) on it elsewhere than on MIPS.
* exec/README: Direct developers to GDB.
* exec/trace.c (finish_exec): Resume the tracee after reporting
an error in `exec'.
(after_fork): If seccomp is enabled on Android, and the kernel
is 4.7 or earlier, detect whether revisions to the sequencing of
seccomp events have been backported from 4.8.
(exec_waitpid): Resume the process with PTRACE_CONT after
receiving an unknown signal.
(exec_init): Cease disabling seccomp on Android kernels earlier
than 4.8.
* exec/configure.ac (REENTRANT): Remove option for reentrancy.
(PROGRAM_COUNTER, HAVE_SECCOMP): Define register providing the
program counter and enable seccomp if its headers are available.
* exec/exec.c (write_load_command): Avoid defining unused
variable.
(exec_0): Remove code specific to REENTRANT configurations.
* exec/exec.h (struct exec_tracee) <exec_data, data_size>: New
fields for loader instructions and their size.
* exec/exec1.c (main): Call exec_init before forking.
* exec/mipsel-user.h (ELF_NGREG): Delete definition.
(struct mipsel_regs): Reduce number of gregs to 32, but
introduce separate fields for special registers.
* exec/trace.c (use_seccomp_p): New variable; defile to false if
!HAVE_SECCOMP.
(remove_tracee): Cease providing for non-reentrant
configurations. Release executable data if present.
(handle_clone_prepare): Likewise. Resume process with
PTRACE_CONT if seccomp-based interception is enabled.
(handle_clone, check_signal): Resume processes as above.
(handle_exec): Divide into two functions, with only rewriting
the system call and generating instructions for the loader
remaining in the first, and copying such instructions into the
loader's stack removed into a new function, `finish_exec'.
(finish_exec): New function.
(handle_readlinkat, handle_openat): Abolish non-REENTRANT
configurations.
(process_system_call): Divide exec system calls into two phases,
disambiguated by the value of tracee->waiting_for_syscall. Typo
fixes. Accommodate syscall-exit-stops where the signal was
initially intercepted by `seccomp_system_call'.
(interesting_syscalls): New array.
(ARRAYELTS): New macro.
(seccomp_system_call, establish_seccomp_filter): New function.
(tracing_execve) [HAVE_SECCOMP]: Establish a seccomp filter if
this is to be enabled.
(after_fork): Provide PTRACE_O_TRACESECCOMP. Resume process
with PTRACE_CONT if seccomp-based interception is enabled.
(exec_waitpid): Resume process with PTRACE_CONT if seccomp-based
interception is enabled. Dispatch stops identifying as
PTRACE_EVENT_SECCOMP to `seccomp_system_call'.
(exec_init): Establish whether it is possible to enable seccomp.
* exec/configure.ac (USER_SWORD): New macro.
* exec/exec.c (format_pid): Export this function.
* exec/exec.h:
* exec/trace.c (canon_path): New function.
(handle_readlinkat, handle_openat): Test complete file name
against /proc/self/exe, and further check for /proc/pid/exe.
* exec/configure.ac (OPEN_SYSCALL, OPENAT_SYSCALL): Define new
macros.
* exec/exec.h (struct exec_tracee): New field `sp'.
* exec/trace.c (handle_openat): New function.
(process_system_call): If handle_openat executes successfully,
save the unmodified stack pointer within the tracee structure to
be restored once the system call completes.
* exec/trace.c (process_system_call) <READLINKAT_SYSCALL>:
Examine tracee->waiting_for_syscall and avoid rewriting user
arguments if a system call is presently being executed by the
kernel. Reported by Romário Rios <romariorios@protonmail.com>.
* exec/exec.h (struct exec_tracee): New field `new_child'.
Also, make `waiting_for_syscall' a bitfield.
* exec/trace.c (PTRACE_GETEVENTMSG): New declaration.
(MAX_TRACEES): Bump to 4096.
(handle_clone_prepare): New function.
(handle_clone): If required, set `new_child' and wait for a
ptrace event describing the parent to arrive.
(after_fork): Clear new field.
(exec_waitpid): Upon a ptrace event describing a clone, create
the child's tracee if it doesn't already exist. Otherwise, copy
over the parent's cmdline and start running it.
* exec/trace.c (check_signal): New function.
(handle_exec, process_system_call): Handle signal-delivery-stop
while waiting synchronously for syscall completion.
* exec/config.h.in: Autoheader.
* exec/configure.ac: Check for siginfo_t.si_syscall.
* exec/trace.c (exec_waitpid): If SIGSYS is received, and caused by
seccomp, drop it should the call number be the invalid system call
used by Emacs.
* exec/config.h.in: Autoheader.
* exec/configure.ac: Use system extensions.
(HAVE_PROCESS_VM): Define if process_vm_readv and
process_vm_writev are available.
* exec/trace.c (read_memory, user_copy): Implement in terms of
process_vm if possible.
* exec/config.h.in (__bool_true_false_are_defined):
* exec/configure.ac (REENTRANT): New definition.
(READLINKAT_SYSCALL, READLINK_SYSCALL): New defines. Set on all
hosts.
* exec/exec.c (MIN, MAX): Remove redundant declarations. Move
to config.h.
(exec_0): Copy name of executable into NAME when !REENTRANT.
* exec/exec.h (struct exec_tracee): New struct `exec_file'.
* exec/trace.c (remove_tracee, handle_exec, handle_readlinkat)
(process_system_call, after_fork): Handle readlinkat system
calls.
