autofs: make dev ioctl version and ismountpoint user accessible
Some of the autofs miscellaneous device ioctls need to be accessable to
user space applications without CAP_SYS_ADMIN to get information about
autofs mounts.
Link: http://lkml.kernel.org/r/150216642517.11652.2338933266137331637.stgit@pluto.themaw.net
Signed-off-by: Ian Kent <raven@themaw.net>
Cc: Colin Walters <walters@redhat.com>
Cc: Ondrej Holy <oholy@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/autofs4/dev-ioctl.c b/fs/autofs4/dev-ioctl.c
index 218a4ec..ea8b3a1 100644
--- a/fs/autofs4/dev-ioctl.c
+++ b/fs/autofs4/dev-ioctl.c
@@ -628,10 +628,6 @@ static int _autofs_dev_ioctl(unsigned int command,
ioctl_fn fn = NULL;
int err = 0;
- /* only root can play with this */
- if (!capable(CAP_SYS_ADMIN))
- return -EPERM;
-
cmd_first = _IOC_NR(AUTOFS_DEV_IOCTL_IOC_FIRST);
cmd = _IOC_NR(command);
@@ -640,6 +636,14 @@ static int _autofs_dev_ioctl(unsigned int command,
return -ENOTTY;
}
+ /* Only root can use ioctls other than AUTOFS_DEV_IOCTL_VERSION_CMD
+ * and AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD
+ */
+ if (cmd != AUTOFS_DEV_IOCTL_VERSION_CMD &&
+ cmd != AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD &&
+ !capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
/* Copy the parameters into kernel space. */
param = copy_dev_ioctl(user);
if (IS_ERR(param))
diff --git a/include/uapi/linux/auto_dev-ioctl.h b/include/uapi/linux/auto_dev-ioctl.h
index 744b3d0..5558db8 100644
--- a/include/uapi/linux/auto_dev-ioctl.h
+++ b/include/uapi/linux/auto_dev-ioctl.h
@@ -16,7 +16,7 @@
#define AUTOFS_DEVICE_NAME "autofs"
#define AUTOFS_DEV_IOCTL_VERSION_MAJOR 1
-#define AUTOFS_DEV_IOCTL_VERSION_MINOR 0
+#define AUTOFS_DEV_IOCTL_VERSION_MINOR 1
#define AUTOFS_DEV_IOCTL_SIZE sizeof(struct autofs_dev_ioctl)