You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
66 lines
1.7 KiB
66 lines
1.7 KiB
4 years ago
|
commit b04acb2651e0aaf615de50e9138cddfd5c24021f
|
||
|
Author: Andreas Schwab <schwab@suse.de>
|
||
|
Date: Tue Jul 30 11:58:45 2013 +0200
|
||
|
|
||
|
Fix race conditions in pldd that may leave the process stopped after detaching
|
||
|
|
||
|
Fixes bug 15804
|
||
|
|
||
|
diff --git a/elf/pldd.c b/elf/pldd.c
|
||
|
index 684aff4..75f7812 100644
|
||
|
--- a/elf/pldd.c
|
||
|
+++ b/elf/pldd.c
|
||
|
@@ -34,6 +34,7 @@
|
||
|
#include <unistd.h>
|
||
|
#include <sys/ptrace.h>
|
||
|
#include <sys/stat.h>
|
||
|
+#include <sys/wait.h>
|
||
|
|
||
|
#include <ldsodefs.h>
|
||
|
#include <version.h>
|
||
|
@@ -82,6 +83,7 @@ static char *exe;
|
||
|
|
||
|
/* Local functions. */
|
||
|
static int get_process_info (int dfd, long int pid);
|
||
|
+static void wait_for_ptrace_stop (long int pid);
|
||
|
|
||
|
|
||
|
int
|
||
|
@@ -170,6 +172,8 @@ main (int argc, char *argv[])
|
||
|
tid);
|
||
|
}
|
||
|
|
||
|
+ wait_for_ptrace_stop (tid);
|
||
|
+
|
||
|
struct thread_list *newp = alloca (sizeof (*newp));
|
||
|
newp->tid = tid;
|
||
|
newp->next = thread_list;
|
||
|
@@ -194,6 +198,27 @@ main (int argc, char *argv[])
|
||
|
}
|
||
|
|
||
|
|
||
|
+/* Wait for PID to enter ptrace-stop state after being attached. */
|
||
|
+static void
|
||
|
+wait_for_ptrace_stop (long int pid)
|
||
|
+{
|
||
|
+ int status;
|
||
|
+
|
||
|
+ /* While waiting for SIGSTOP being delivered to the tracee we have to
|
||
|
+ reinject any other pending signal. Ignore all other errors. */
|
||
|
+ while (waitpid (pid, &status, __WALL) == pid && WIFSTOPPED (status))
|
||
|
+ {
|
||
|
+ /* The STOP signal should not be delivered to the tracee. */
|
||
|
+ if (WSTOPSIG (status) == SIGSTOP)
|
||
|
+ return;
|
||
|
+ if (ptrace (PTRACE_CONT, pid, NULL,
|
||
|
+ (void *) (uintptr_t) WSTOPSIG (status)))
|
||
|
+ /* The only possible error is that the process died. */
|
||
|
+ return;
|
||
|
+ }
|
||
|
+}
|
||
|
+
|
||
|
+
|
||
|
/* Handle program arguments. */
|
||
|
static error_t
|
||
|
parse_opt (int key, char *arg, struct argp_state *state)
|