Merge pull request #1529 from brauner/2017-04-28/create_proc_if_missing

utils: tweak lxc_mount_proc_if_needed()
This commit is contained in:
Serge Hallyn 2017-04-28 20:06:07 -05:00 committed by GitHub
commit c0614b0c23
3 changed files with 32 additions and 20 deletions

View File

@ -3760,20 +3760,21 @@ int ttys_shift_ids(struct lxc_conf *c)
return 0;
}
/* NOTE: not to be called from inside the container namespace! */
int tmp_proc_mount(struct lxc_conf *lxc_conf)
/* NOTE: Must not be called from inside the container namespace! */
int lxc_create_tmp_proc_mount(struct lxc_conf *conf)
{
int mounted;
mounted = mount_proc_if_needed(lxc_conf->rootfs.path ? lxc_conf->rootfs.mount : "");
mounted = lxc_mount_proc_if_needed(conf->rootfs.path ? conf->rootfs.mount : "");
if (mounted == -1) {
SYSERROR("failed to mount /proc in the container.");
SYSERROR("failed to mount /proc in the container");
/* continue only if there is no rootfs */
if (lxc_conf->rootfs.path)
if (conf->rootfs.path)
return -1;
} else if (mounted == 1) {
lxc_conf->tmp_umount_proc = 1;
conf->tmp_umount_proc = 1;
}
return 0;
}
@ -4063,7 +4064,7 @@ int lxc_setup(struct lxc_handler *handler)
}
/* mount /proc if it's not already there */
if (tmp_proc_mount(lxc_conf) < 0) {
if (lxc_create_tmp_proc_mount(lxc_conf) < 0) {
ERROR("failed to LSM mount proc for '%s'", name);
return -1;
}

View File

@ -1754,7 +1754,7 @@ int safe_mount(const char *src, const char *dest, const char *fstype,
*
* NOTE: not to be called from inside the container namespace!
*/
int mount_proc_if_needed(const char *rootfs)
int lxc_mount_proc_if_needed(const char *rootfs)
{
char path[MAXPATHLEN];
char link[20];
@ -1766,37 +1766,48 @@ int mount_proc_if_needed(const char *rootfs)
SYSERROR("proc path name too long");
return -1;
}
memset(link, 0, 20);
linklen = readlink(path, link, 20);
mypid = (int)getpid();
INFO("I am %d, /proc/self points to '%s'", mypid, link);
INFO("I am %d, /proc/self points to \"%s\"", mypid, link);
ret = snprintf(path, MAXPATHLEN, "%s/proc", rootfs);
if (ret < 0 || ret >= MAXPATHLEN) {
SYSERROR("proc path name too long");
return -1;
}
if (linklen < 0) /* /proc not mounted */
goto domount;
if (lxc_safe_int(link, &link_to_pid) < 0)
/* /proc not mounted */
if (linklen < 0) {
if (mkdir(path, 0755) && errno != EEXIST)
return -1;
if (link_to_pid != mypid) {
/* wrong /procs mounted */
umount2(path, MNT_DETACH); /* ignore failure */
goto domount;
}
if (lxc_safe_int(link, &link_to_pid) < 0)
return -1;
/* wrong /procs mounted */
if (link_to_pid != mypid) {
/* ignore failure */
umount2(path, MNT_DETACH);
goto domount;
}
/* the right proc is already mounted */
return 0;
domount:
if (!strcmp(rootfs,"")) /* rootfs is NULL */
/* rootfs is NULL */
if (!strcmp(rootfs,""))
ret = mount("proc", path, "proc", 0, NULL);
else
ret = safe_mount("proc", path, "proc", 0, NULL, rootfs);
if (ret < 0)
return -1;
INFO("Mounted /proc in container for security transition");
INFO("mounted /proc in container for security transition");
return 1;
}

View File

@ -326,7 +326,7 @@ char *get_template_path(const char *t);
int setproctitle(char *title);
int safe_mount(const char *src, const char *dest, const char *fstype,
unsigned long flags, const void *data, const char *rootfs);
int mount_proc_if_needed(const char *rootfs);
int lxc_mount_proc_if_needed(const char *rootfs);
int open_devnull(void);
int set_stdfds(int fd);
int null_stdfds(void);