#include <sched.h>
#include <sys/signal.h>
-#include <common/error.h>
+#include <common/common.h>
+#include <common/utils.h>
#include <common/compat/mman.h>
#include <common/compat/clone.h>
#define RUNAS_CHILD_STACK_SIZE 10485760
+#ifndef MAP_STACK
+#define MAP_STACK 0
+#endif
+
#ifdef __FreeBSD__
/* FreeBSD MAP_STACK always return -ENOMEM */
#define LTTNG_MAP_STACK 0
mode_t mode;
};
+#ifdef VALGRIND
+static
+int use_clone(void)
+{
+ return 0;
+}
+#else
+static
+int use_clone(void)
+{
+ return !getenv("LTTNG_DEBUG_NOCLONE");
+}
+#endif
+
/*
* Create recursively directory using the FULL path.
*/
{
struct run_as_mkdir_data *data = _data;
const char *path;
- char *p, tmp[PATH_MAX];
- struct stat statbuf;
mode_t mode;
- size_t len;
- int ret;
path = data->path;
mode = data->mode;
- ret = snprintf(tmp, sizeof(tmp), "%s", path);
- if (ret < 0) {
- PERROR("snprintf mkdir");
- goto error;
- }
-
- len = ret;
- if (tmp[len - 1] == '/') {
- tmp[len - 1] = 0;
- }
-
- for (p = tmp + 1; *p; p++) {
- if (*p == '/') {
- *p = 0;
- ret = stat(tmp, &statbuf);
- if (ret < 0) {
- ret = mkdir(tmp, mode);
- if (ret < 0) {
- if (!(errno == EEXIST)) {
- PERROR("mkdir recursive");
- ret = -errno;
- goto error;
- }
- }
- }
- *p = '/';
- }
- }
-
- ret = mkdir(tmp, mode);
- if (ret < 0) {
- if (!(errno == EEXIST)) {
- PERROR("mkdir recursive last piece");
- ret = -errno;
- } else {
- ret = 0;
- }
- }
-
-error:
- return ret;
+ return utils_mkdir_recursive(path, mode);
}
static
int _mkdir(void *_data)
{
+ int ret;
struct run_as_mkdir_data *data = _data;
- return mkdir(data->path, data->mode);
+
+ ret = mkdir(data->path, data->mode);
+ if (ret < 0) {
+ ret = -errno;
+ }
+
+ return ret;
}
static
static
int child_run_as(void *_data)
{
- struct run_as_data *data = _data;
- size_t writelen, writeleft, index;
- union {
- int i;
- char c[sizeof(int)];
- } sendret;
int ret;
+ struct run_as_data *data = _data;
+ ssize_t writelen;
+ int sendret;
/*
* Child: it is safe to drop egid and euid while sharing the
ret = setegid(data->gid);
if (ret < 0) {
PERROR("setegid");
- return EXIT_FAILURE;
+ sendret = -1;
+ goto write_return;
}
}
if (data->uid != geteuid()) {
ret = seteuid(data->uid);
if (ret < 0) {
PERROR("seteuid");
- return EXIT_FAILURE;
+ sendret = -1;
+ goto write_return;
}
}
/*
* Also set umask to 0 for mkdir executable bit.
*/
umask(0);
- sendret.i = (*data->cmd)(data->data);
+ sendret = (*data->cmd)(data->data);
+
+write_return:
/* send back return value */
- writeleft = sizeof(sendret);
- index = 0;
- do {
- writelen = write(data->retval_pipe, &sendret.c[index],
- writeleft);
- if (writelen < 0) {
- PERROR("write");
- return EXIT_FAILURE;
- }
- writeleft -= writelen;
- index += writelen;
- } while (writeleft > 0);
- return EXIT_SUCCESS;
+ writelen = lttng_write(data->retval_pipe, &sendret, sizeof(sendret));
+ if (writelen < sizeof(sendret)) {
+ PERROR("lttng_write error");
+ return EXIT_FAILURE;
+ } else {
+ return EXIT_SUCCESS;
+ }
}
static
{
struct run_as_data run_as_data;
int ret = 0;
+ ssize_t readlen;
int status;
pid_t pid;
int retval_pipe[2];
- ssize_t readlen, readleft, index;
void *child_stack;
- union {
- int i;
- char c[sizeof(int)];
- } retval;
+ int retval;
/*
* If we are non-root, we can only deal with our own uid.
ret = pipe(retval_pipe);
if (ret < 0) {
PERROR("pipe");
- retval.i = ret;
+ retval = ret;
goto end;
}
run_as_data.data = data;
-1, 0);
if (child_stack == MAP_FAILED) {
PERROR("mmap");
- retval.i = -ENOMEM;
+ retval = -ENOMEM;
goto close_pipe;
}
/*
&run_as_data);
if (pid < 0) {
PERROR("clone");
- retval.i = pid;
+ retval = pid;
goto unmap_stack;
}
/* receive return value */
- readleft = sizeof(retval);
- index = 0;
- do {
- readlen = read(retval_pipe[0], &retval.c[index], readleft);
- if (readlen < 0) {
- PERROR("read");
- ret = -1;
- break;
- }
- readleft -= readlen;
- index += readlen;
- } while (readleft > 0);
+ readlen = lttng_read(retval_pipe[0], &retval, sizeof(retval));
+ if (readlen < sizeof(retval)) {
+ ret = -1;
+ }
/*
* Parent: wait for child to return, in which case the
pid = waitpid(pid, &status, 0);
if (pid < 0 || !WIFEXITED(status) || WEXITSTATUS(status) != 0) {
PERROR("wait");
- retval.i = -1;
+ retval = -1;
}
unmap_stack:
ret = munmap(child_stack, RUNAS_CHILD_STACK_SIZE);
if (ret < 0) {
PERROR("munmap");
- retval.i = ret;
+ retval = ret;
}
close_pipe:
ret = close(retval_pipe[0]);
PERROR("close");
}
end:
- return retval.i;
+ return retval;
}
/*
static
int run_as_noclone(int (*cmd)(void *data), void *data, uid_t uid, gid_t gid)
{
- return cmd(data);
+ int ret;
+ mode_t old_mask;
+
+ old_mask = umask(0);
+ ret = cmd(data);
+ umask(old_mask);
+
+ return ret;
}
static
int run_as(int (*cmd)(void *data), void *data, uid_t uid, gid_t gid)
{
- if (!getenv("LTTNG_DEBUG_NOCLONE")) {
+ if (use_clone()) {
+ int ret;
+
DBG("Using run_as_clone");
- return run_as_clone(cmd, data, uid, gid);
+ pthread_mutex_lock(<tng_libc_state_lock);
+ ret = run_as_clone(cmd, data, uid, gid);
+ pthread_mutex_unlock(<tng_libc_state_lock);
+ return ret;
} else {
DBG("Using run_as_noclone");
return run_as_noclone(cmd, data, uid, gid);
}
}
+LTTNG_HIDDEN
int run_as_mkdir_recursive(const char *path, mode_t mode, uid_t uid, gid_t gid)
{
struct run_as_mkdir_data data;
return run_as(_mkdir_recursive, &data, uid, gid);
}
+LTTNG_HIDDEN
int run_as_mkdir(const char *path, mode_t mode, uid_t uid, gid_t gid)
{
struct run_as_mkdir_data data;
* Note: open_run_as is currently not working. We'd need to pass the fd
* opened in the child to the parent.
*/
+LTTNG_HIDDEN
int run_as_open(const char *path, int flags, mode_t mode, uid_t uid, gid_t gid)
{
struct run_as_open_data data;