diff options
| -rw-r--r-- | src/base/linuxthreads.cc | 38 |
1 files changed, 19 insertions, 19 deletions
diff --git a/src/base/linuxthreads.cc b/src/base/linuxthreads.cc index ba4d1c8..47bb011 100644 --- a/src/base/linuxthreads.cc +++ b/src/base/linuxthreads.cc @@ -416,7 +416,7 @@ static void ListerThread(struct ListerParams *args) { /* Check if the marker is identical to the one we created */ if (sys_stat(fname, &tmp_sb) >= 0 && marker_sb.st_ino == tmp_sb.st_ino) { - long i; + long i, j; /* Found one of our threads, make sure it is no duplicate */ for (i = 0; i < num_threads; i++) { @@ -452,28 +452,28 @@ static void ListerThread(struct ListerParams *args) { sig_num_threads = num_threads; goto next_entry; } - /* Attaching to a process doesn't guarantee it'll stop before - * ptrace returns; you have to wait on it. Specifying __WCLONE - * means it will only wait for clone children (i.e. threads, - * not processes). - */ - while (sys_waitpid(pid, (int *)0, __WCLONE) < 0) { + while (sys_waitpid(pid, (int *)0, __WALL) < 0) { if (errno != EINTR) { - /* Assumes ECHILD */ - if (pid == ppid) { - /* The parent is not a clone */ - found_parent = true; - break; - } else { - sys_ptrace_detach(pid); - num_threads--; - sig_num_threads = num_threads; - goto next_entry; - } + sys_ptrace_detach(pid); + num_threads--; + sig_num_threads = num_threads; + goto next_entry; } } - added_entries++; + if (sys_ptrace(PTRACE_PEEKDATA, pid, &i, &j) || i++ != j || + sys_ptrace(PTRACE_PEEKDATA, pid, &i, &j) || i != j) { + /* Address spaces are distinct, even though both + * processes show the "marker". This is probably + * a forked child process rather than a thread. + */ + sys_ptrace_detach(pid); + num_threads--; + sig_num_threads = num_threads; + } else { + found_parent |= pid == ppid; + added_entries++; + } } } } |