This is a note to let you know that I've just added the patch titled mnt: Implicitly add MNT_NODEV on remount when it was implicitly added by mount to the 3.17-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mnt-implicitly-add-mnt_nodev-on-remount-when-it-was-implicitly-added-by-mount.patch and it can be found in the queue-3.17 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 3e1866410f11356a9fd869beb3e95983dc79c067 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> Date: Wed, 13 Aug 2014 01:33:38 -0700 Subject: mnt: Implicitly add MNT_NODEV on remount when it was implicitly added by mount From: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> commit 3e1866410f11356a9fd869beb3e95983dc79c067 upstream. Now that remount is properly enforcing the rule that you can't remove nodev at least sandstorm.io is breaking when performing a remount. It turns out that there is an easy intuitive solution implicitly add nodev on remount when nodev was implicitly added on mount. Tested-by: Cedric Bosdonnat <cbosdonnat@xxxxxxxx> Tested-by: Richard Weinberger <richard@xxxxxx> Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/namespace.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1957,7 +1957,13 @@ static int do_remount(struct path *path, } if ((mnt->mnt.mnt_flags & MNT_LOCK_NODEV) && !(mnt_flags & MNT_NODEV)) { - return -EPERM; + /* Was the nodev implicitly added in mount? */ + if ((mnt->mnt_ns->user_ns != &init_user_ns) && + !(sb->s_type->fs_flags & FS_USERNS_DEV_MOUNT)) { + mnt_flags |= MNT_NODEV; + } else { + return -EPERM; + } } if ((mnt->mnt.mnt_flags & MNT_LOCK_NOSUID) && !(mnt_flags & MNT_NOSUID)) { Patches currently in stable-queue which might be from ebiederm@xxxxxxxxxxxx are queue-3.17/mnt-update-unprivileged-remount-test.patch queue-3.17/mnt-fix-a-memory-stomp-in-umount.patch queue-3.17/userns-check-euid-no-fsuid-when-establishing-an-unprivileged-uid-mapping.patch queue-3.17/mnt-implicitly-add-mnt_nodev-on-remount-when-it-was-implicitly-added-by-mount.patch queue-3.17/userns-don-t-allow-unprivileged-creation-of-gid-mappings.patch queue-3.17/userns-rename-id_map_mutex-to-userns_state_mutex.patch queue-3.17/userns-add-a-knob-to-disable-setgroups-on-a-per-user-namespace-basis.patch queue-3.17/userns-allow-setting-gid_maps-without-privilege-when-setgroups-is-disabled.patch queue-3.17/userns-don-t-allow-setgroups-until-a-gid-mapping-has-been-setablished.patch queue-3.17/groups-consolidate-the-setgroups-permission-checks.patch queue-3.17/userns-only-allow-the-creator-of-the-userns-unprivileged-mappings.patch queue-3.17/userns-document-what-the-invariant-required-for-safe-unprivileged-mappings.patch queue-3.17/umount-disallow-unprivileged-mount-force.patch queue-3.17/userns-unbreak-the-unprivileged-remount-tests.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html