| /* Copyright (C) 2020-2024 Free Software Foundation, Inc. |
| |
| This file is part of GDB. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| |
| #include "target.h" |
| #include "netbsd-low.h" |
| #include "nat/netbsd-nat.h" |
| |
| #include <sys/param.h> |
| #include <sys/types.h> |
| |
| #include <sys/ptrace.h> |
| #include <sys/sysctl.h> |
| |
| #include <limits.h> |
| #include <unistd.h> |
| #include <signal.h> |
| |
| #include <elf.h> |
| |
| #include <type_traits> |
| |
| #include "gdbsupport/eintr.h" |
| #include "gdbsupport/gdb_wait.h" |
| #include "gdbsupport/filestuff.h" |
| #include "gdbsupport/common-inferior.h" |
| #include "nat/fork-inferior.h" |
| #include "hostio.h" |
| |
| int using_threads = 1; |
| |
| /* Callback used by fork_inferior to start tracing the inferior. */ |
| |
| static void |
| netbsd_ptrace_fun () |
| { |
| /* Switch child to its own process group so that signals won't |
| directly affect GDBserver. */ |
| if (setpgid (0, 0) < 0) |
| trace_start_error_with_name (("setpgid")); |
| |
| if (ptrace (PT_TRACE_ME, 0, nullptr, 0) < 0) |
| trace_start_error_with_name (("ptrace")); |
| |
| /* If GDBserver is connected to gdb via stdio, redirect the inferior's |
| stdout to stderr so that inferior i/o doesn't corrupt the connection. |
| Also, redirect stdin to /dev/null. */ |
| if (remote_connection_is_stdio ()) |
| { |
| if (close (0) < 0) |
| trace_start_error_with_name (("close")); |
| if (open ("/dev/null", O_RDONLY) < 0) |
| trace_start_error_with_name (("open")); |
| if (dup2 (2, 1) < 0) |
| trace_start_error_with_name (("dup2")); |
| if (write (2, "stdin/stdout redirected\n", |
| sizeof ("stdin/stdout redirected\n") - 1) < 0) |
| { |
| /* Errors ignored. */ |
| } |
| } |
| } |
| |
| /* Implement the create_inferior method of the target_ops vector. */ |
| |
| int |
| netbsd_process_target::create_inferior (const char *program, |
| const std::vector<char *> &program_args) |
| { |
| std::string str_program_args = construct_inferior_arguments (program_args); |
| |
| pid_t pid = fork_inferior (program, str_program_args.c_str (), |
| get_environ ()->envp (), netbsd_ptrace_fun, |
| nullptr, nullptr, nullptr, nullptr); |
| |
| add_process (pid, 0); |
| |
| post_fork_inferior (pid, program); |
| |
| return pid; |
| } |
| |
| /* Implement the post_create_inferior target_ops method. */ |
| |
| void |
| netbsd_process_target::post_create_inferior () |
| { |
| pid_t pid = current_process ()->pid; |
| netbsd_nat::enable_proc_events (pid); |
| |
| low_arch_setup (); |
| } |
| |
| /* Implement the attach target_ops method. */ |
| |
| int |
| netbsd_process_target::attach (unsigned long pid) |
| { |
| /* Unimplemented. */ |
| return -1; |
| } |
| |
| /* Returns true if GDB is interested in any child syscalls. */ |
| |
| static bool |
| gdb_catching_syscalls_p (pid_t pid) |
| { |
| struct process_info *proc = find_process_pid (pid); |
| return !proc->syscalls_to_catch.empty (); |
| } |
| |
| /* Implement the resume target_ops method. */ |
| |
| void |
| netbsd_process_target::resume (struct thread_resume *resume_info, size_t n) |
| { |
| ptid_t resume_ptid = resume_info[0].thread; |
| const int signal = resume_info[0].sig; |
| const bool step = resume_info[0].kind == resume_step; |
| |
| if (resume_ptid == minus_one_ptid) |
| resume_ptid = ptid_of (current_thread); |
| |
| const pid_t pid = resume_ptid.pid (); |
| const lwpid_t lwp = resume_ptid.lwp (); |
| regcache_invalidate_pid (pid); |
| |
| auto fn |
| = [&] (ptid_t ptid) |
| { |
| if (step) |
| { |
| if (ptid.lwp () == lwp || n != 1) |
| { |
| if (ptrace (PT_SETSTEP, pid, NULL, ptid.lwp ()) == -1) |
| perror_with_name (("ptrace")); |
| if (ptrace (PT_RESUME, pid, NULL, ptid.lwp ()) == -1) |
| perror_with_name (("ptrace")); |
| } |
| else |
| { |
| if (ptrace (PT_CLEARSTEP, pid, NULL, ptid.lwp ()) == -1) |
| perror_with_name (("ptrace")); |
| if (ptrace (PT_SUSPEND, pid, NULL, ptid.lwp ()) == -1) |
| perror_with_name (("ptrace")); |
| } |
| } |
| else |
| { |
| if (ptrace (PT_CLEARSTEP, pid, NULL, ptid.lwp ()) == -1) |
| perror_with_name (("ptrace")); |
| if (ptrace (PT_RESUME, pid, NULL, ptid.lwp ()) == -1) |
| perror_with_name (("ptrace")); |
| } |
| }; |
| |
| netbsd_nat::for_each_thread (pid, fn); |
| |
| int request = gdb_catching_syscalls_p (pid) ? PT_CONTINUE : PT_SYSCALL; |
| |
| errno = 0; |
| ptrace (request, pid, (void *)1, signal); |
| if (errno) |
| perror_with_name (("ptrace")); |
| } |
| |
| /* Returns true if GDB is interested in the reported SYSNO syscall. */ |
| |
| static bool |
| netbsd_catch_this_syscall (int sysno) |
| { |
| struct process_info *proc = current_process (); |
| |
| if (proc->syscalls_to_catch.empty ()) |
| return false; |
| |
| if (proc->syscalls_to_catch[0] == ANY_SYSCALL) |
| return true; |
| |
| for (int iter : proc->syscalls_to_catch) |
| if (iter == sysno) |
| return true; |
| |
| return false; |
| } |
| |
| /* Helper function for child_wait and the derivatives of child_wait. |
| HOSTSTATUS is the waitstatus from wait() or the equivalent; store our |
| translation of that in OURSTATUS. */ |
| |
| static void |
| netbsd_store_waitstatus (struct target_waitstatus *ourstatus, int hoststatus) |
| { |
| if (WIFEXITED (hoststatus)) |
| ourstatus->set_exited (WEXITSTATUS (hoststatus)); |
| else if (!WIFSTOPPED (hoststatus)) |
| ourstatus->set_signalled (gdb_signal_from_host (WTERMSIG (hoststatus))); |
| else |
| ourstatus->set_stopped (gdb_signal_from_host (WSTOPSIG (hoststatus))); |
| } |
| |
| /* Implement a safe wrapper around waitpid(). */ |
| |
| static pid_t |
| netbsd_waitpid (ptid_t ptid, struct target_waitstatus *ourstatus, |
| target_wait_flags target_options) |
| { |
| int status; |
| int options = (target_options & TARGET_WNOHANG) ? WNOHANG : 0; |
| |
| pid_t pid |
| = gdb::handle_eintr (-1, ::waitpid, ptid.pid (), &status, options); |
| |
| if (pid == -1) |
| perror_with_name (_("Child process unexpectedly missing")); |
| |
| netbsd_store_waitstatus (ourstatus, status); |
| return pid; |
| } |
| |
| |
| /* Implement the wait target_ops method. |
| |
| Wait for the child specified by PTID to do something. Return the |
| process ID of the child, or MINUS_ONE_PTID in case of error; store |
| the status in *OURSTATUS. */ |
| |
| static ptid_t |
| netbsd_wait (ptid_t ptid, struct target_waitstatus *ourstatus, |
| target_wait_flags target_options) |
| { |
| pid_t pid = netbsd_waitpid (ptid, ourstatus, target_options); |
| ptid_t wptid = ptid_t (pid); |
| |
| if (pid == 0) |
| { |
| gdb_assert (target_options & TARGET_WNOHANG); |
| ourstatus->set_ignore (); |
| return null_ptid; |
| } |
| |
| gdb_assert (pid != -1); |
| |
| /* If the child stopped, keep investigating its status. */ |
| if (ourstatus->kind () != TARGET_WAITKIND_STOPPED) |
| return wptid; |
| |
| /* Extract the event and thread that received a signal. */ |
| ptrace_siginfo_t psi; |
| if (ptrace (PT_GET_SIGINFO, pid, &psi, sizeof (psi)) == -1) |
| perror_with_name (("ptrace")); |
| |
| /* Pick child's siginfo_t. */ |
| siginfo_t *si = &psi.psi_siginfo; |
| |
| lwpid_t lwp = psi.psi_lwpid; |
| |
| int signo = si->si_signo; |
| const int code = si->si_code; |
| |
| /* Construct PTID with a specified thread that received the event. |
| If a signal was targeted to the whole process, lwp is 0. */ |
| wptid = ptid_t (pid, lwp, 0); |
| |
| /* Bail out on non-debugger oriented signals. */ |
| if (signo != SIGTRAP) |
| return wptid; |
| |
| /* Stop examining non-debugger oriented SIGTRAP codes. */ |
| if (code <= SI_USER || code == SI_NOINFO) |
| return wptid; |
| |
| /* Process state for threading events. */ |
| ptrace_state_t pst = {}; |
| if (code == TRAP_LWP) |
| if (ptrace (PT_GET_PROCESS_STATE, pid, &pst, sizeof (pst)) == -1) |
| perror_with_name (("ptrace")); |
| |
| if (code == TRAP_LWP && pst.pe_report_event == PTRACE_LWP_EXIT) |
| { |
| /* If GDB attaches to a multi-threaded process, exiting |
| threads might be skipped during post_attach that |
| have not yet reported their PTRACE_LWP_EXIT event. |
| Ignore exited events for an unknown LWP. */ |
| thread_info *thr = find_thread_ptid (wptid); |
| if (thr == nullptr) |
| ourstatus->set_spurious (); |
| else |
| { |
| /* NetBSD does not store an LWP exit status. */ |
| ourstatus->set_thread_exited (0); |
| |
| remove_thread (thr); |
| } |
| return wptid; |
| } |
| |
| if (find_thread_ptid (ptid_t (pid))) |
| switch_to_thread (find_thread_ptid (wptid)); |
| |
| if (code == TRAP_LWP && pst.pe_report_event == PTRACE_LWP_CREATE) |
| { |
| /* If GDB attaches to a multi-threaded process, newborn |
| threads might be added by nbsd_add_threads that have |
| not yet reported their PTRACE_LWP_CREATE event. Ignore |
| born events for an already-known LWP. */ |
| if (find_thread_ptid (wptid)) |
| ourstatus->set_spurious (); |
| else |
| { |
| add_thread (wptid, NULL); |
| ourstatus->set_thread_created (); |
| } |
| return wptid; |
| } |
| |
| if (code == TRAP_EXEC) |
| { |
| ourstatus->set_execd |
| (make_unique_xstrdup (netbsd_nat::pid_to_exec_file (pid))); |
| return wptid; |
| } |
| |
| if (code == TRAP_TRACE) |
| return wptid; |
| |
| if (code == TRAP_SCE || code == TRAP_SCX) |
| { |
| int sysnum = si->si_sysnum; |
| |
| if (!netbsd_catch_this_syscall(sysnum)) |
| { |
| /* If the core isn't interested in this event, ignore it. */ |
| ourstatus->set_spurious (); |
| return wptid; |
| } |
| |
| if (code == TRAP_SCE) |
| ourstatus->set_syscall_entry (sysnum); |
| else |
| ourstatus->set_syscall_return (sysnum); |
| |
| return wptid; |
| } |
| |
| if (code == TRAP_BRKPT) |
| { |
| #ifdef PTRACE_BREAKPOINT_ADJ |
| CORE_ADDR pc; |
| struct reg r; |
| ptrace (PT_GETREGS, pid, &r, psi.psi_lwpid); |
| pc = PTRACE_REG_PC (&r); |
| PTRACE_REG_SET_PC (&r, pc - PTRACE_BREAKPOINT_ADJ); |
| ptrace (PT_SETREGS, pid, &r, psi.psi_lwpid); |
| #endif |
| return wptid; |
| } |
| |
| /* Unclassified SIGTRAP event. */ |
| ourstatus->set_spurious (); |
| return wptid; |
| } |
| |
| /* Implement the wait target_ops method. */ |
| |
| ptid_t |
| netbsd_process_target::wait (ptid_t ptid, struct target_waitstatus *ourstatus, |
| target_wait_flags target_options) |
| { |
| while (true) |
| { |
| ptid_t wptid = netbsd_wait (ptid, ourstatus, target_options); |
| |
| /* Register thread in the gdbcore if a thread was not reported earlier. |
| This is required after ::create_inferior, when the gdbcore does not |
| know about the first internal thread. |
| This may also happen on attach, when an event is registered on a thread |
| that was not fully initialized during the attach stage. */ |
| if (wptid.lwp () != 0 && !find_thread_ptid (wptid) |
| && ourstatus->kind () != TARGET_WAITKIND_THREAD_EXITED) |
| add_thread (wptid, nullptr); |
| |
| switch (ourstatus->kind ()) |
| { |
| case TARGET_WAITKIND_EXITED: |
| case TARGET_WAITKIND_STOPPED: |
| case TARGET_WAITKIND_SIGNALLED: |
| case TARGET_WAITKIND_FORKED: |
| case TARGET_WAITKIND_VFORKED: |
| case TARGET_WAITKIND_EXECD: |
| case TARGET_WAITKIND_VFORK_DONE: |
| case TARGET_WAITKIND_SYSCALL_ENTRY: |
| case TARGET_WAITKIND_SYSCALL_RETURN: |
| /* Pass the result to the generic code. */ |
| return wptid; |
| case TARGET_WAITKIND_THREAD_CREATED: |
| case TARGET_WAITKIND_THREAD_EXITED: |
| /* The core needlessly stops on these events. */ |
| [[fallthrough]]; |
| case TARGET_WAITKIND_SPURIOUS: |
| /* Spurious events are unhandled by the gdbserver core. */ |
| if (ptrace (PT_CONTINUE, current_process ()->pid, (void *) 1, 0) |
| == -1) |
| perror_with_name (("ptrace")); |
| break; |
| default: |
| error (("Unknown stopped status")); |
| } |
| } |
| } |
| |
| /* Implement the kill target_ops method. */ |
| |
| int |
| netbsd_process_target::kill (process_info *process) |
| { |
| pid_t pid = process->pid; |
| if (ptrace (PT_KILL, pid, nullptr, 0) == -1) |
| return -1; |
| |
| int status; |
| if (gdb::handle_eintr (-1, ::waitpid, pid, &status, 0) == -1) |
| return -1; |
| mourn (process); |
| return 0; |
| } |
| |
| /* Implement the detach target_ops method. */ |
| |
| int |
| netbsd_process_target::detach (process_info *process) |
| { |
| pid_t pid = process->pid; |
| |
| ptrace (PT_DETACH, pid, (void *) 1, 0); |
| mourn (process); |
| return 0; |
| } |
| |
| /* Implement the mourn target_ops method. */ |
| |
| void |
| netbsd_process_target::mourn (struct process_info *proc) |
| { |
| for_each_thread (proc->pid, remove_thread); |
| |
| remove_process (proc); |
| } |
| |
| /* Implement the join target_ops method. */ |
| |
| void |
| netbsd_process_target::join (int pid) |
| { |
| /* The PT_DETACH is sufficient to detach from the process. |
| So no need to do anything extra. */ |
| } |
| |
| /* Implement the thread_alive target_ops method. */ |
| |
| bool |
| netbsd_process_target::thread_alive (ptid_t ptid) |
| { |
| return netbsd_nat::thread_alive (ptid); |
| } |
| |
| /* Implement the fetch_registers target_ops method. */ |
| |
| void |
| netbsd_process_target::fetch_registers (struct regcache *regcache, int regno) |
| { |
| const netbsd_regset_info *regset = get_regs_info (); |
| ptid_t inferior_ptid = ptid_of (current_thread); |
| |
| while (regset->size >= 0) |
| { |
| std::vector<char> buf; |
| buf.resize (regset->size); |
| int res = ptrace (regset->get_request, inferior_ptid.pid (), buf.data (), |
| inferior_ptid.lwp ()); |
| if (res == -1) |
| perror_with_name (("ptrace")); |
| regset->store_function (regcache, buf.data ()); |
| regset++; |
| } |
| } |
| |
| /* Implement the store_registers target_ops method. */ |
| |
| void |
| netbsd_process_target::store_registers (struct regcache *regcache, int regno) |
| { |
| const netbsd_regset_info *regset = get_regs_info (); |
| ptid_t inferior_ptid = ptid_of (current_thread); |
| |
| while (regset->size >= 0) |
| { |
| std::vector<char> buf; |
| buf.resize (regset->size); |
| int res = ptrace (regset->get_request, inferior_ptid.pid (), buf.data (), |
| inferior_ptid.lwp ()); |
| if (res == -1) |
| perror_with_name (("ptrace")); |
| |
| /* Then overlay our cached registers on that. */ |
| regset->fill_function (regcache, buf.data ()); |
| /* Only now do we write the register set. */ |
| res = ptrace (regset->set_request, inferior_ptid.pid (), buf. data (), |
| inferior_ptid.lwp ()); |
| if (res == -1) |
| perror_with_name (("ptrace")); |
| regset++; |
| } |
| } |
| |
| /* Implement the read_memory target_ops method. */ |
| |
| int |
| netbsd_process_target::read_memory (CORE_ADDR memaddr, unsigned char *myaddr, |
| int size) |
| { |
| pid_t pid = current_process ()->pid; |
| return netbsd_nat::read_memory (pid, myaddr, memaddr, size, nullptr); |
| } |
| |
| /* Implement the write_memory target_ops method. */ |
| |
| int |
| netbsd_process_target::write_memory (CORE_ADDR memaddr, |
| const unsigned char *myaddr, int size) |
| { |
| pid_t pid = current_process ()->pid; |
| return netbsd_nat::write_memory (pid, myaddr, memaddr, size, nullptr); |
| } |
| |
| /* Implement the request_interrupt target_ops method. */ |
| |
| void |
| netbsd_process_target::request_interrupt () |
| { |
| ptid_t inferior_ptid = ptid_of (get_first_thread ()); |
| |
| ::kill (inferior_ptid.pid (), SIGINT); |
| } |
| |
| /* Read the AUX Vector for the specified PID, wrapping the ptrace(2) call |
| with the PIOD_READ_AUXV operation and using the PT_IO standard input |
| and output arguments. */ |
| |
| static size_t |
| netbsd_read_auxv(pid_t pid, void *offs, void *addr, size_t len) |
| { |
| struct ptrace_io_desc pio; |
| |
| pio.piod_op = PIOD_READ_AUXV; |
| pio.piod_offs = offs; |
| pio.piod_addr = addr; |
| pio.piod_len = len; |
| |
| if (ptrace (PT_IO, pid, &pio, 0) == -1) |
| perror_with_name (("ptrace")); |
| |
| return pio.piod_len; |
| } |
| |
| /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET |
| to debugger memory starting at MYADDR. */ |
| |
| int |
| netbsd_process_target::read_auxv (int pid, CORE_ADDR offset, |
| unsigned char *myaddr, unsigned int len) |
| { |
| return netbsd_read_auxv (pid, (void *) (intptr_t) offset, myaddr, len); |
| } |
| |
| bool |
| netbsd_process_target::supports_z_point_type (char z_type) |
| { |
| switch (z_type) |
| { |
| case Z_PACKET_SW_BP: |
| return true; |
| case Z_PACKET_HW_BP: |
| case Z_PACKET_WRITE_WP: |
| case Z_PACKET_READ_WP: |
| case Z_PACKET_ACCESS_WP: |
| default: |
| return false; /* Not supported. */ |
| } |
| } |
| |
| /* Insert {break/watch}point at address ADDR. SIZE is not used. */ |
| |
| int |
| netbsd_process_target::insert_point (enum raw_bkpt_type type, CORE_ADDR addr, |
| int size, struct raw_breakpoint *bp) |
| { |
| switch (type) |
| { |
| case raw_bkpt_type_sw: |
| return insert_memory_breakpoint (bp); |
| case raw_bkpt_type_hw: |
| case raw_bkpt_type_write_wp: |
| case raw_bkpt_type_read_wp: |
| case raw_bkpt_type_access_wp: |
| default: |
| return 1; /* Not supported. */ |
| } |
| } |
| |
| /* Remove {break/watch}point at address ADDR. SIZE is not used. */ |
| |
| int |
| netbsd_process_target::remove_point (enum raw_bkpt_type type, CORE_ADDR addr, |
| int size, struct raw_breakpoint *bp) |
| { |
| switch (type) |
| { |
| case raw_bkpt_type_sw: |
| return remove_memory_breakpoint (bp); |
| case raw_bkpt_type_hw: |
| case raw_bkpt_type_write_wp: |
| case raw_bkpt_type_read_wp: |
| case raw_bkpt_type_access_wp: |
| default: |
| return 1; /* Not supported. */ |
| } |
| } |
| |
| /* Implement the stopped_by_sw_breakpoint target_ops method. */ |
| |
| bool |
| netbsd_process_target::stopped_by_sw_breakpoint () |
| { |
| ptrace_siginfo_t psi; |
| pid_t pid = current_process ()->pid; |
| |
| if (ptrace (PT_GET_SIGINFO, pid, &psi, sizeof (psi)) == -1) |
| perror_with_name (("ptrace")); |
| |
| return psi.psi_siginfo.si_signo == SIGTRAP && |
| psi.psi_siginfo.si_code == TRAP_BRKPT; |
| } |
| |
| /* Implement the supports_stopped_by_sw_breakpoint target_ops method. */ |
| |
| bool |
| netbsd_process_target::supports_stopped_by_sw_breakpoint () |
| { |
| return true; |
| } |
| |
| /* Implement the supports_qxfer_siginfo target_ops method. */ |
| |
| bool |
| netbsd_process_target::supports_qxfer_siginfo () |
| { |
| return true; |
| } |
| |
| /* Implement the qxfer_siginfo target_ops method. */ |
| |
| int |
| netbsd_process_target::qxfer_siginfo (const char *annex, unsigned char *readbuf, |
| unsigned const char *writebuf, |
| CORE_ADDR offset, int len) |
| { |
| if (current_thread == nullptr) |
| return -1; |
| |
| pid_t pid = current_process ()->pid; |
| |
| return netbsd_nat::qxfer_siginfo(pid, annex, readbuf, writebuf, offset, len); |
| } |
| |
| /* Implement the supports_non_stop target_ops method. */ |
| |
| bool |
| netbsd_process_target::supports_non_stop () |
| { |
| return false; |
| } |
| |
| /* Implement the supports_multi_process target_ops method. */ |
| |
| bool |
| netbsd_process_target::supports_multi_process () |
| { |
| return true; |
| } |
| |
| /* Check if fork events are supported. */ |
| |
| bool |
| netbsd_process_target::supports_fork_events () |
| { |
| return false; |
| } |
| |
| /* Check if vfork events are supported. */ |
| |
| bool |
| netbsd_process_target::supports_vfork_events () |
| { |
| return false; |
| } |
| |
| /* Check if exec events are supported. */ |
| |
| bool |
| netbsd_process_target::supports_exec_events () |
| { |
| return true; |
| } |
| |
| /* Implement the supports_disable_randomization target_ops method. */ |
| |
| bool |
| netbsd_process_target::supports_disable_randomization () |
| { |
| return false; |
| } |
| |
| /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */ |
| |
| template <typename T> |
| int get_phdr_phnum_from_proc_auxv (const pid_t pid, |
| CORE_ADDR *phdr_memaddr, int *num_phdr) |
| { |
| typedef typename std::conditional<sizeof(T) == sizeof(int64_t), |
| Aux64Info, Aux32Info>::type auxv_type; |
| const size_t auxv_size = sizeof (auxv_type); |
| const size_t auxv_buf_size = 128 * sizeof (auxv_type); |
| |
| std::vector<char> auxv_buf; |
| auxv_buf.resize (auxv_buf_size); |
| |
| netbsd_read_auxv (pid, nullptr, auxv_buf.data (), auxv_buf_size); |
| |
| *phdr_memaddr = 0; |
| *num_phdr = 0; |
| |
| for (char *buf = auxv_buf.data (); |
| buf < (auxv_buf.data () + auxv_buf_size); |
| buf += auxv_size) |
| { |
| auxv_type *const aux = (auxv_type *) buf; |
| |
| switch (aux->a_type) |
| { |
| case AT_PHDR: |
| *phdr_memaddr = aux->a_v; |
| break; |
| case AT_PHNUM: |
| *num_phdr = aux->a_v; |
| break; |
| } |
| |
| if (*phdr_memaddr != 0 && *num_phdr != 0) |
| break; |
| } |
| |
| if (*phdr_memaddr == 0 || *num_phdr == 0) |
| { |
| warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: " |
| "phdr_memaddr = %s, phdr_num = %d", |
| core_addr_to_string (*phdr_memaddr), *num_phdr); |
| return 2; |
| } |
| |
| return 0; |
| } |
| |
| /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */ |
| |
| template <typename T> |
| static CORE_ADDR |
| get_dynamic (const pid_t pid) |
| { |
| typedef typename std::conditional<sizeof(T) == sizeof(int64_t), |
| Elf64_Phdr, Elf32_Phdr>::type phdr_type; |
| const int phdr_size = sizeof (phdr_type); |
| |
| CORE_ADDR phdr_memaddr; |
| int num_phdr; |
| if (get_phdr_phnum_from_proc_auxv<T> (pid, &phdr_memaddr, &num_phdr)) |
| return 0; |
| |
| std::vector<unsigned char> phdr_buf; |
| phdr_buf.resize (num_phdr * phdr_size); |
| |
| if (netbsd_nat::read_memory (pid, phdr_buf.data (), phdr_memaddr, |
| phdr_buf.size (), nullptr)) |
| return 0; |
| |
| /* Compute relocation: it is expected to be 0 for "regular" executables, |
| non-zero for PIE ones. */ |
| CORE_ADDR relocation = -1; |
| for (int i = 0; relocation == -1 && i < num_phdr; i++) |
| { |
| phdr_type *const p = (phdr_type *) (phdr_buf.data () + i * phdr_size); |
| |
| if (p->p_type == PT_PHDR) |
| relocation = phdr_memaddr - p->p_vaddr; |
| } |
| |
| if (relocation == -1) |
| { |
| /* PT_PHDR is optional, but necessary for PIE in general. Fortunately |
| any real world executables, including PIE executables, have always |
| PT_PHDR present. PT_PHDR is not present in some shared libraries or |
| in fpc (Free Pascal 2.4) binaries but neither of those have a need for |
| or present DT_DEBUG anyway (fpc binaries are statically linked). |
| |
| Therefore if there exists DT_DEBUG there is always also PT_PHDR. |
| |
| GDB could find RELOCATION also from AT_ENTRY - e_entry. */ |
| |
| return 0; |
| } |
| |
| for (int i = 0; i < num_phdr; i++) |
| { |
| phdr_type *const p = (phdr_type *) (phdr_buf.data () + i * phdr_size); |
| |
| if (p->p_type == PT_DYNAMIC) |
| return p->p_vaddr + relocation; |
| } |
| |
| return 0; |
| } |
| |
| /* Return &_r_debug in the inferior, or -1 if not present. Return value |
| can be 0 if the inferior does not yet have the library list initialized. |
| We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of |
| DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */ |
| |
| template <typename T> |
| static CORE_ADDR |
| get_r_debug (const pid_t pid) |
| { |
| typedef typename std::conditional<sizeof(T) == sizeof(int64_t), |
| Elf64_Dyn, Elf32_Dyn>::type dyn_type; |
| const int dyn_size = sizeof (dyn_type); |
| unsigned char buf[sizeof (dyn_type)]; /* The larger of the two. */ |
| CORE_ADDR map = -1; |
| |
| CORE_ADDR dynamic_memaddr = get_dynamic<T> (pid); |
| if (dynamic_memaddr == 0) |
| return map; |
| |
| while (netbsd_nat::read_memory (pid, buf, dynamic_memaddr, dyn_size, nullptr) |
| == 0) |
| { |
| dyn_type *const dyn = (dyn_type *) buf; |
| #if defined DT_MIPS_RLD_MAP |
| union |
| { |
| T map; |
| unsigned char buf[sizeof (T)]; |
| } |
| rld_map; |
| |
| if (dyn->d_tag == DT_MIPS_RLD_MAP) |
| { |
| if (netbsd_nat::read_memory (pid, rld_map.buf, dyn->d_un.d_val, |
| sizeof (rld_map.buf), nullptr) == 0) |
| return rld_map.map; |
| else |
| break; |
| } |
| #endif /* DT_MIPS_RLD_MAP */ |
| |
| if (dyn->d_tag == DT_DEBUG && map == -1) |
| map = dyn->d_un.d_val; |
| |
| if (dyn->d_tag == DT_NULL) |
| break; |
| |
| dynamic_memaddr += dyn_size; |
| } |
| |
| return map; |
| } |
| |
| /* Read one pointer from MEMADDR in the inferior. */ |
| |
| static int |
| read_one_ptr (const pid_t pid, CORE_ADDR memaddr, CORE_ADDR *ptr, int ptr_size) |
| { |
| /* Go through a union so this works on either big or little endian |
| hosts, when the inferior's pointer size is smaller than the size |
| of CORE_ADDR. It is assumed the inferior's endianness is the |
| same of the superior's. */ |
| |
| union |
| { |
| CORE_ADDR core_addr; |
| unsigned int ui; |
| unsigned char uc; |
| } addr; |
| |
| int ret = netbsd_nat::read_memory (pid, &addr.uc, memaddr, ptr_size, nullptr); |
| if (ret == 0) |
| { |
| if (ptr_size == sizeof (CORE_ADDR)) |
| *ptr = addr.core_addr; |
| else if (ptr_size == sizeof (unsigned int)) |
| *ptr = addr.ui; |
| else |
| gdb_assert_not_reached ("unhandled pointer size"); |
| } |
| return ret; |
| } |
| |
| /* Construct qXfer:libraries-svr4:read reply. */ |
| |
| template <typename T> |
| int |
| netbsd_qxfer_libraries_svr4 (const pid_t pid, const char *annex, |
| unsigned char *readbuf, |
| unsigned const char *writebuf, |
| CORE_ADDR offset, int len) |
| { |
| struct link_map_offsets |
| { |
| /* Offset and size of r_debug.r_version. */ |
| int r_version_offset; |
| |
| /* Offset and size of r_debug.r_map. */ |
| int r_map_offset; |
| |
| /* Offset to l_addr field in struct link_map. */ |
| int l_addr_offset; |
| |
| /* Offset to l_name field in struct link_map. */ |
| int l_name_offset; |
| |
| /* Offset to l_ld field in struct link_map. */ |
| int l_ld_offset; |
| |
| /* Offset to l_next field in struct link_map. */ |
| int l_next_offset; |
| |
| /* Offset to l_prev field in struct link_map. */ |
| int l_prev_offset; |
| }; |
| |
| static const struct link_map_offsets lmo_32bit_offsets = |
| { |
| 0, /* r_version offset. */ |
| 4, /* r_debug.r_map offset. */ |
| 0, /* l_addr offset in link_map. */ |
| 4, /* l_name offset in link_map. */ |
| 8, /* l_ld offset in link_map. */ |
| 12, /* l_next offset in link_map. */ |
| 16 /* l_prev offset in link_map. */ |
| }; |
| |
| static const struct link_map_offsets lmo_64bit_offsets = |
| { |
| 0, /* r_version offset. */ |
| 8, /* r_debug.r_map offset. */ |
| 0, /* l_addr offset in link_map. */ |
| 8, /* l_name offset in link_map. */ |
| 16, /* l_ld offset in link_map. */ |
| 24, /* l_next offset in link_map. */ |
| 32 /* l_prev offset in link_map. */ |
| }; |
| |
| CORE_ADDR lm_addr = 0, lm_prev = 0; |
| CORE_ADDR l_name, l_addr, l_ld, l_next, l_prev; |
| int header_done = 0; |
| |
| const struct link_map_offsets *lmo |
| = ((sizeof (T) == sizeof (int64_t)) |
| ? &lmo_64bit_offsets : &lmo_32bit_offsets); |
| int ptr_size = sizeof (T); |
| |
| while (annex[0] != '\0') |
| { |
| const char *sep = strchr (annex, '='); |
| if (sep == nullptr) |
| break; |
| |
| int name_len = sep - annex; |
| CORE_ADDR *addrp; |
| if (name_len == 5 && startswith (annex, "start")) |
| addrp = &lm_addr; |
| else if (name_len == 4 && startswith (annex, "prev")) |
| addrp = &lm_prev; |
| else |
| { |
| annex = strchr (sep, ';'); |
| if (annex == nullptr) |
| break; |
| annex++; |
| continue; |
| } |
| |
| annex = decode_address_to_semicolon (addrp, sep + 1); |
| } |
| |
| if (lm_addr == 0) |
| { |
| CORE_ADDR r_debug = get_r_debug<T> (pid); |
| |
| /* We failed to find DT_DEBUG. Such situation will not change |
| for this inferior - do not retry it. Report it to GDB as |
| E01, see for the reasons at the GDB solib-svr4.c side. */ |
| if (r_debug == (CORE_ADDR) -1) |
| return -1; |
| |
| if (r_debug != 0) |
| { |
| CORE_ADDR map_offset = r_debug + lmo->r_map_offset; |
| if (read_one_ptr (pid, map_offset, &lm_addr, ptr_size) != 0) |
| warning ("unable to read r_map from %s", |
| core_addr_to_string (map_offset)); |
| } |
| } |
| |
| std::string document = "<library-list-svr4 version=\"1.0\""; |
| |
| while (lm_addr |
| && read_one_ptr (pid, lm_addr + lmo->l_name_offset, |
| &l_name, ptr_size) == 0 |
| && read_one_ptr (pid, lm_addr + lmo->l_addr_offset, |
| &l_addr, ptr_size) == 0 |
| && read_one_ptr (pid, lm_addr + lmo->l_ld_offset, |
| &l_ld, ptr_size) == 0 |
| && read_one_ptr (pid, lm_addr + lmo->l_prev_offset, |
| &l_prev, ptr_size) == 0 |
| && read_one_ptr (pid, lm_addr + lmo->l_next_offset, |
| &l_next, ptr_size) == 0) |
| { |
| if (lm_prev != l_prev) |
| { |
| warning ("Corrupted shared library list: 0x%lx != 0x%lx", |
| (long) lm_prev, (long) l_prev); |
| break; |
| } |
| |
| /* Ignore the first entry even if it has valid name as the first entry |
| corresponds to the main executable. The first entry should not be |
| skipped if the dynamic loader was loaded late by a static executable |
| (see solib-svr4.c parameter ignore_first). But in such case the main |
| executable does not have PT_DYNAMIC present and this function already |
| exited above due to failed get_r_debug. */ |
| if (lm_prev == 0) |
| string_appendf (document, " main-lm=\"0x%lx\"", |
| (unsigned long) lm_addr); |
| else |
| { |
| unsigned char libname[PATH_MAX]; |
| |
| /* Not checking for error because reading may stop before |
| we've got PATH_MAX worth of characters. */ |
| libname[0] = '\0'; |
| netbsd_nat::read_memory (pid, libname, l_name, sizeof (libname) - 1, |
| nullptr); |
| libname[sizeof (libname) - 1] = '\0'; |
| if (libname[0] != '\0') |
| { |
| if (!header_done) |
| { |
| /* Terminate `<library-list-svr4'. */ |
| document += '>'; |
| header_done = 1; |
| } |
| |
| string_appendf (document, "<library name=\""); |
| xml_escape_text_append (document, (char *) libname); |
| string_appendf (document, "\" lm=\"0x%lx\" " |
| "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>", |
| (unsigned long) lm_addr, (unsigned long) l_addr, |
| (unsigned long) l_ld); |
| } |
| } |
| |
| lm_prev = lm_addr; |
| lm_addr = l_next; |
| } |
| |
| if (!header_done) |
| { |
| /* Empty list; terminate `<library-list-svr4'. */ |
| document += "/>"; |
| } |
| else |
| document += "</library-list-svr4>"; |
| |
| int document_len = document.length (); |
| if (offset < document_len) |
| document_len -= offset; |
| else |
| document_len = 0; |
| if (len > document_len) |
| len = document_len; |
| |
| memcpy (readbuf, document.data () + offset, len); |
| |
| return len; |
| } |
| |
| /* Return true if FILE is a 64-bit ELF file, |
| false if the file is not a 64-bit ELF file, |
| and error if the file is not accessible or doesn't exist. */ |
| |
| static bool |
| elf_64_file_p (const char *file) |
| { |
| int fd = gdb::handle_eintr (-1, ::open, file, O_RDONLY); |
| if (fd < 0) |
| perror_with_name (("open")); |
| |
| Elf64_Ehdr header; |
| ssize_t ret = gdb::handle_eintr (-1, ::read, fd, &header, sizeof (header)); |
| if (ret == -1) |
| perror_with_name (("read")); |
| gdb::handle_eintr (-1, ::close, fd); |
| if (ret != sizeof (header)) |
| error ("Cannot read ELF file header: %s", file); |
| |
| if (header.e_ident[EI_MAG0] != ELFMAG0 |
| || header.e_ident[EI_MAG1] != ELFMAG1 |
| || header.e_ident[EI_MAG2] != ELFMAG2 |
| || header.e_ident[EI_MAG3] != ELFMAG3) |
| error ("Unrecognized ELF file header: %s", file); |
| |
| return header.e_ident[EI_CLASS] == ELFCLASS64; |
| } |
| |
| /* Construct qXfer:libraries-svr4:read reply. */ |
| |
| int |
| netbsd_process_target::qxfer_libraries_svr4 (const char *annex, |
| unsigned char *readbuf, |
| unsigned const char *writebuf, |
| CORE_ADDR offset, int len) |
| { |
| if (writebuf != nullptr) |
| return -2; |
| if (readbuf == nullptr) |
| return -1; |
| |
| struct process_info *proc = current_process (); |
| pid_t pid = proc->pid; |
| bool is_elf64 = elf_64_file_p (netbsd_nat::pid_to_exec_file (pid)); |
| |
| if (is_elf64) |
| return netbsd_qxfer_libraries_svr4<int64_t> (pid, annex, readbuf, |
| writebuf, offset, len); |
| else |
| return netbsd_qxfer_libraries_svr4<int32_t> (pid, annex, readbuf, |
| writebuf, offset, len); |
| } |
| |
| /* Implement the supports_qxfer_libraries_svr4 target_ops method. */ |
| |
| bool |
| netbsd_process_target::supports_qxfer_libraries_svr4 () |
| { |
| return true; |
| } |
| |
| /* Return the name of a file that can be opened to get the symbols for |
| the child process identified by PID. */ |
| |
| const char * |
| netbsd_process_target::pid_to_exec_file (pid_t pid) |
| { |
| return netbsd_nat::pid_to_exec_file (pid); |
| } |
| |
| /* Implementation of the target_ops method "supports_pid_to_exec_file". */ |
| |
| bool |
| netbsd_process_target::supports_pid_to_exec_file () |
| { |
| return true; |
| } |
| |
| /* Implementation of the target_ops method "supports_hardware_single_step". */ |
| bool |
| netbsd_process_target::supports_hardware_single_step () |
| { |
| return true; |
| } |
| |
| /* Implementation of the target_ops method "sw_breakpoint_from_kind". */ |
| |
| const gdb_byte * |
| netbsd_process_target::sw_breakpoint_from_kind (int kind, int *size) |
| { |
| static gdb_byte brkpt[PTRACE_BREAKPOINT_SIZE] = {*PTRACE_BREAKPOINT}; |
| |
| *size = PTRACE_BREAKPOINT_SIZE; |
| |
| return brkpt; |
| } |
| |
| /* Implement the thread_name target_ops method. */ |
| |
| const char * |
| netbsd_process_target::thread_name (ptid_t ptid) |
| { |
| return netbsd_nat::thread_name (ptid); |
| } |
| |
| /* Implement the supports_catch_syscall target_ops method. */ |
| |
| bool |
| netbsd_process_target::supports_catch_syscall () |
| { |
| return true; |
| } |
| |
| /* Implement the supports_read_auxv target_ops method. */ |
| |
| bool |
| netbsd_process_target::supports_read_auxv () |
| { |
| return true; |
| } |
| |
| void |
| initialize_low () |
| { |
| set_target_ops (the_netbsd_target); |
| } |