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-rw-r--r--runtime/staprun/staprun.c163
1 files changed, 85 insertions, 78 deletions
diff --git a/runtime/staprun/staprun.c b/runtime/staprun/staprun.c
index 8db2ac5b..f9ca8e45 100644
--- a/runtime/staprun/staprun.c
+++ b/runtime/staprun/staprun.c
@@ -16,21 +16,18 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
- * Copyright (C) 2005-2007 Red Hat, Inc.
+ * Copyright (C) 2005-2008 Red Hat, Inc.
*
*/
#include "staprun.h"
-int inserted_module = 0;
-
/* used in dbug, _err and _perr */
char *__name__ = "staprun";
extern long delete_module(const char *, unsigned int);
-static int
-run_as(uid_t uid, gid_t gid, const char *path, char *const argv[])
+static int run_as(uid_t uid, gid_t gid, const char *path, char *const argv[])
{
pid_t pid;
int rstatus;
@@ -42,14 +39,13 @@ run_as(uid_t uid, gid_t gid, const char *path, char *const argv[])
err("%s ", argv[i]);
i++;
}
- err("\n");
+ err("\n");
}
if ((pid = fork()) < 0) {
_perr("fork");
return -1;
- }
- else if (pid == 0) {
+ } else if (pid == 0) {
/* Make sure we run as the full user. If we're
* switching to a non-root user, this won't allow
* that process to switch back to root (since the
@@ -79,17 +75,6 @@ run_as(uid_t uid, gid_t gid, const char *path, char *const argv[])
return -1;
}
-/* Keep the uid and gid settings because we will likely */
-/* conditionally restore "-u" */
-static int run_stapio(char **argv)
-{
- uid_t uid = getuid();
- gid_t gid = getgid();
- argv[0] = PKGLIBDIR "/stapio";
-
- return run_as(uid, gid, argv[0], argv);
-}
-
/*
* Module to be inserted has one or more user-space probes. Make sure
* uprobes is enabled.
@@ -132,8 +117,7 @@ static int enable_uprobes(void)
dbug(2, "Inserting uprobes module from SystemTap runtime.\n");
argv[0] = NULL;
- return insert_module(PKGDATADIR "/runtime/uprobes/uprobes.ko",
- NULL, argv);
+ return insert_module(PKGDATADIR "/runtime/uprobes/uprobes.ko", NULL, argv);
}
static int insert_stap_module(void)
@@ -144,6 +128,66 @@ static int insert_stap_module(void)
return insert_module(modpath, bufsize_option, modoptions);
}
+static int remove_module(const char *name, int verb);
+
+static void remove_all_modules(void)
+{
+ char *base;
+ struct statfs st;
+ struct dirent *d;
+ DIR *moddir;
+
+ if (statfs("/sys/kernel/debug", &st) == 0 && (int)st.f_type == (int)DEBUGFS_MAGIC)
+ base = "/sys/kernel/debug/systemtap";
+ else
+ base = "/proc/systemtap";
+
+ moddir = opendir(base);
+ if (moddir) {
+ while ((d = readdir(moddir)))
+ if (remove_module(d->d_name, 0) == 0)
+ printf("Module %s removed.\n", d->d_name);
+ closedir(moddir);
+ }
+}
+
+static int remove_module(const char *name, int verb)
+{
+ int ret;
+ dbug(2, "%s\n", name);
+
+ if (strcmp(name, "*") == 0) {
+ remove_all_modules();
+ return 0;
+ }
+
+ /* Call init_ctl_channel() which actually attempts an open()
+ * of the control channel. This is better than using access() because
+ * an open on an already open channel will fail, preventing us from attempting
+ * to remove an in-use module.
+ */
+ if (init_ctl_channel(name, 0) < 0) {
+ if (verb)
+ err("Error accessing systemtap module %s: %s\n", name, strerror(errno));
+ return 1;
+ }
+ close_ctl_channel();
+
+ dbug(2, "removing module %s\n", name);
+
+ /* Don't remove module when priority is elevated. */
+ if (setpriority(PRIO_PROCESS, 0, 0) < 0)
+ _perr("setpriority");
+
+ ret = do_cap(CAP_SYS_MODULE, delete_module, name, 0);
+ if (ret != 0) {
+ err("Error removing module '%s': %s.\n", name, strerror(errno));
+ return 1;
+ }
+
+ dbug(1, "Module %s removed.\n", name);
+ return 0;
+}
int init_staprun(void)
{
@@ -154,69 +198,28 @@ int init_staprun(void)
/* We're done with CAP_SYS_ADMIN. */
drop_cap(CAP_SYS_ADMIN);
-
- if (!attach_mod) {
+
+ if (delete_mod)
+ exit(remove_module(modname, 1));
+ else if (!attach_mod) {
if (need_uprobes && enable_uprobes() != 0)
return -1;
if (insert_stap_module() < 0)
return -1;
- else
- inserted_module = 1;
}
-
return 0;
}
-
-static void cleanup(int rc)
-{
- /* Only cleanup once. */
- static int done = 0;
- if (done == 0)
- done = 1;
- else
- return;
-
- dbug(2, "rc=%d, inserted_module=%d\n", rc, inserted_module);
-
- if (setpriority (PRIO_PROCESS, 0, 0) < 0)
- _perr("setpriority");
-
- /* rc == 2 means disconnected */
- if (rc == 2)
- return;
-
- /* If we inserted the module and did not get rc==2, then */
- /* we really want to remove it. */
- if (inserted_module || rc == 3) {
- long ret;
- dbug(2, "removing module %s\n", modname);
- ret = do_cap(CAP_SYS_MODULE, delete_module, modname, 0);
- if (ret != 0)
- err("Error removing module '%s': %s\n", modname, moderror(errno));
- }
-}
-
-static void exit_cleanup(void)
-{
- dbug(2, "something exited...\n");
- cleanup(1);
-}
int main(int argc, char **argv)
{
int rc;
- if (atexit(exit_cleanup)) {
- _perr("cannot set exit function");
- exit(1);
- }
-
- /* NB: Don't do the geteuid()!=0 check here, since we want to
- test command-line error-handling while running non-root. */
+ /* NB: Don't do the geteuid()!=0 check here, since we want to
+ test command-line error-handling while running non-root. */
/* Get rid of a few standard environment variables (which */
/* might cause us to do unintended things). */
rc = unsetenv("IFS") || unsetenv("CDPATH") || unsetenv("ENV")
- || unsetenv("BASH_ENV");
+ || unsetenv("BASH_ENV");
if (rc) {
_perr("unsetenv failed");
exit(-1);
@@ -234,13 +237,13 @@ int main(int argc, char **argv)
dbug(2, "modpath=\"%s\", modname=\"%s\"\n", modpath, modname);
}
- if (optind < argc) {
+ if (optind < argc) {
if (attach_mod) {
err("ERROR: Cannot have module options with attach (-A).\n");
usage(argv[0]);
} else {
unsigned start_idx = 0;
- while (optind < argc && start_idx+1 < MAXMODOPTIONS)
+ while (optind < argc && start_idx + 1 < MAXMODOPTIONS)
modoptions[start_idx++] = argv[optind++];
modoptions[start_idx] = NULL;
}
@@ -252,8 +255,8 @@ int main(int argc, char **argv)
}
if (geteuid() != 0) {
- err("ERROR: The effective user ID of staprun must be set to the root user.\n"
- " Check permissions on staprun and ensure it is a setuid root program.\n");
+ err("ERROR: The effective user ID of staprun must be set to the root user.\n"
+ " Check permissions on staprun and ensure it is a setuid root program.\n");
exit(1);
}
@@ -275,10 +278,14 @@ int main(int argc, char **argv)
if (init_staprun())
exit(1);
- setup_staprun_signals();
-
- rc = run_stapio(argv);
- cleanup(rc);
-
+ argv[0] = PKGLIBDIR "/stapio";
+ if (execv(argv[0], argv) < 0) {
+ perror(argv[0]);
+ goto err;
+ }
return 0;
+
+err:
+ remove_module(modname, 1);
+ return 1;
}
generated by cgit (git 2.34.1) at 2025-08-05 12:01:19 +0000