linux_dsm_epyc7002/fs
Eric W. Biederman 5e4a08476b userns: Require CAP_SYS_ADMIN for most uses of setns.
Andy Lutomirski <luto@amacapital.net> found a nasty little bug in
the permissions of setns.  With unprivileged user namespaces it
became possible to create new namespaces without privilege.

However the setns calls were relaxed to only require CAP_SYS_ADMIN in
the user nameapce of the targed namespace.

Which made the following nasty sequence possible.

pid = clone(CLONE_NEWUSER | CLONE_NEWNS);
if (pid == 0) { /* child */
	system("mount --bind /home/me/passwd /etc/passwd");
}
else if (pid != 0) { /* parent */
	char path[PATH_MAX];
	snprintf(path, sizeof(path), "/proc/%u/ns/mnt");
	fd = open(path, O_RDONLY);
	setns(fd, 0);
	system("su -");
}

Prevent this possibility by requiring CAP_SYS_ADMIN
in the current user namespace when joing all but the user namespace.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-12-14 16:12:03 -08:00
..
9p The following changes since commit 4cbe5a555f: 2012-10-12 09:59:23 +09:00
adfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
affs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
afs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
autofs4 userns: Support autofs4 interacing with multiple user namespaces 2012-11-14 22:05:32 -08:00
befs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
bfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
btrfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2012-10-26 09:34:04 -07:00
cachefiles fs: cachefiles: add support for large files in filesystem caching 2012-07-30 17:25:21 -07:00
ceph tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking 2012-10-09 23:33:55 -04:00
cifs Merge branch 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux 2012-10-14 13:39:34 -07:00
coda fs: push rcu_barrier() from deactivate_locked_super() to filesystems 2012-10-02 21:35:55 -04:00
configfs userns: Convert configfs to use kuid and kgid where appropriate 2012-09-18 01:01:37 -07:00
cramfs userns: Convert cramfs to use kuid/kgid where appropriate 2012-09-21 03:13:08 -07:00
debugfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2012-10-02 11:11:09 -07:00
devpts VFS: Pass mount flags to sget() 2012-07-14 16:38:34 +04:00
dlm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2012-10-02 13:38:27 -07:00
ecryptfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
efs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
exofs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-12 10:52:03 +09:00
exportfs switch dentry_open() to struct path, make it grab references itself 2012-07-23 00:01:29 +04:00
ext2 ext2: fix return values on parse_options() failure 2012-10-09 23:23:53 +02:00
ext3 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 2012-10-16 18:12:38 -07:00
ext4 Various bug fixes for ext4. The most serious of them fixes a security 2012-10-23 08:48:26 +03:00
fat fat: drop lock/unlock super 2012-10-09 23:33:38 -04:00
freevxfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
fscache
fuse userns: Support fuse interacting with multiple user namespaces 2012-11-14 22:05:33 -08:00
gfs2 tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking 2012-10-09 23:33:55 -04:00
hfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
hfsplus Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
hostfs Merge branch 'for-linus-37rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml 2012-10-10 11:15:20 +09:00
hpfs hpfs: drop lock/unlock super 2012-10-09 23:33:38 -04:00
hppfs pidns: Use task_active_pid_ns where appropriate 2012-11-19 05:59:09 -08:00
hugetlbfs mm: replace vma prio_tree with an interval tree 2012-10-09 16:22:39 +09:00
isofs tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking 2012-10-09 23:33:55 -04:00
jbd jbd: Fix assertion failure in commit code due to lacking transaction credits 2012-09-12 15:52:03 +02:00
jbd2 The big new feature added this time is supporting online resizing 2012-10-08 06:36:39 +09:00
jffs2 UAPI Disintegration 2012-10-09 2012-10-09 15:04:25 +01:00
jfs jfs: Fix FITRIM argument handling 2012-10-17 09:18:38 -05:00
lockd LOCKD: Clear ln->nsm_clnt only when ln->nsm_users is zero 2012-10-24 10:46:22 -04:00
logfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
minix Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
ncpfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
nfs NFSv4: Fix the return value for nfs_callback_start_svc 2012-10-16 13:14:42 -04:00
nfs_common
nfsd UAPI Disintegration 2012-10-09 2012-10-09 18:35:22 -04:00
nilfs2 mm: kill vma flag VM_CAN_NONLINEAR 2012-10-09 16:22:17 +09:00
nls nls: fix (and rename) mac NLS table files and config options 2012-06-01 19:51:22 -07:00
notify switch simple cases of fget_light to fdget 2012-09-26 22:20:08 -04:00
ntfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
ocfs2 mm: kill vma flag VM_CAN_NONLINEAR 2012-10-09 16:22:17 +09:00
omfs omfs: convert to use beXX_add_cpu() 2012-10-06 03:05:31 +09:00
openpromfs fs: push rcu_barrier() from deactivate_locked_super() to filesystems 2012-10-02 21:35:55 -04:00
proc proc: Usable inode numbers for the namespace file descriptors. 2012-11-20 04:19:49 -08:00
pstore pstore: Avoid recursive spinlocks in the oops_in_progress case 2012-09-20 17:04:50 -07:00
qnx4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
qnx6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
quota Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 2012-10-16 18:12:38 -07:00
ramfs don't pass nameidata to ->create() 2012-07-14 16:34:47 +04:00
reiserfs tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking 2012-10-09 23:33:55 -04:00
romfs fs: push rcu_barrier() from deactivate_locked_super() to filesystems 2012-10-02 21:35:55 -04:00
squashfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
sysfs userns: Allow unprivilged mounts of proc and sysfs 2012-11-20 04:19:18 -08:00
sysv sysv: drop lock/unlock super 2012-10-09 23:33:39 -04:00
ubifs mm: kill vma flag VM_CAN_NONLINEAR 2012-10-09 16:22:17 +09:00
udf Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 2012-10-04 09:14:01 -07:00
ufs ufs: drop lock/unlock super 2012-10-09 23:33:39 -04:00
xfs tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking 2012-10-09 23:33:55 -04:00
aio.c aio: now fput() is OK from interrupt context; get rid of manual delayed __fput() 2012-07-22 23:57:59 +04:00
anon_inodes.c
attr.c userns: Allow chown and setgid preservation 2012-11-20 04:17:24 -08:00
bad_inode.c don't pass nameidata to ->create() 2012-07-14 16:34:47 +04:00
binfmt_aout.c coredump: pass siginfo_t* to do_coredump() and below, not merely signr 2012-10-06 03:05:16 +09:00
binfmt_elf_fdpic.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2012-10-10 12:02:25 +09:00
binfmt_elf.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal 2012-10-10 12:02:25 +09:00
binfmt_em86.c
binfmt_flat.c coredump: pass siginfo_t* to do_coredump() and below, not merely signr 2012-10-06 03:05:16 +09:00
binfmt_misc.c vfs: Rename end_writeback() to clear_inode() 2012-05-06 13:43:41 +08:00
binfmt_script.c
binfmt_som.c VM: add "vm_mmap()" helper function 2012-04-20 17:29:13 -07:00
bio-integrity.c block: Ues bi_pool for bio_integrity_alloc() 2012-09-09 10:35:38 +02:00
bio.c block: makes bio_split support bio without data 2012-09-28 10:38:48 +02:00
block_dev.c Lock splice_read and splice_write functions 2012-10-28 10:59:37 -07:00
buffer.c The big new feature added this time is supporting online resizing 2012-10-08 06:36:39 +09:00
char_dev.c char_dev: pin parent kobject 2012-10-22 08:50:37 +03:00
compat_binfmt_elf.c coredump: extend core dump note section to contain file names of mapped files 2012-10-06 03:05:17 +09:00
compat_ioctl.c fs/compat_ioctl.c: VIDEO_SET_SPU_PALETTE missing error check 2012-10-25 14:37:53 -07:00
compat.c vfs: define struct filename and have getname() return it 2012-10-12 20:14:55 -04:00
coredump.c fix a leak in replace_fd() users 2012-10-16 13:36:50 -04:00
coredump.h coredump: update coredump-related headers 2012-10-06 03:05:15 +09:00
dcache.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
dcookies.c
direct-io.c block: move down direct IO plugging 2012-08-09 15:23:09 +02:00
drop_caches.c
eventfd.c eventfd: change int to __u64 in eventfd_signal() 2012-05-31 17:49:32 -07:00
eventpoll.c epoll: support for disabling items, and a self-test app 2012-10-06 03:05:00 +09:00
exec.c userns: Ignore suid and sgid on binaries if the uid or gid can not be mapped 2012-11-19 05:59:23 -08:00
fcntl.c Fix F_DUPFD_CLOEXEC breakage 2012-10-09 15:52:31 +09:00
fhandle.c switch simple cases of fget_light to fdget 2012-09-26 22:20:08 -04:00
fifo.c fifo: Do not restart open() if it already found a partner 2012-07-16 08:33:14 -07:00
file_table.c lglock: add DEFINE_STATIC_LGLOCK() 2012-10-10 01:15:44 -04:00
file.c dup3: Return an error when oldfd == newfd. 2012-10-09 23:33:38 -04:00
filesystems.c vfs: define struct filename and have getname() return it 2012-10-12 20:14:55 -04:00
fs_struct.c get rid of ->mnt_longterm 2012-07-14 16:32:47 +04:00
fs-writeback.c Merge branch 'writeback-for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux 2012-10-12 10:46:03 +09:00
generic_acl.c userns: Pass a userns parameter into posix_acl_to_xattr and posix_acl_from_xattr 2012-09-18 01:01:35 -07:00
inode.c mm: replace vma prio_tree with an interval tree 2012-10-09 16:22:39 +09:00
internal.h vfs: make path_openat take a struct filename pointer 2012-10-12 20:15:09 -04:00
ioctl.c switch simple cases of fget_light to fdget 2012-09-26 22:20:08 -04:00
ioprio.c Merge branch 'for-3.5/core' of git://git.kernel.dk/linux-block 2012-05-30 08:52:42 -07:00
Kconfig
Kconfig.binfmt coredump: make core dump functionality optional 2012-10-06 03:05:15 +09:00
libfs.c vfs: fix kerneldoc for generic_fh_to_parent() 2012-09-05 10:59:30 +02:00
locks.c UAPI Disintegration 2012-10-09 2012-10-09 18:35:22 -04:00
Makefile coredump: make core dump functionality optional 2012-10-06 03:05:15 +09:00
mbcache.c
mount.h proc: Usable inode numbers for the namespace file descriptors. 2012-11-20 04:19:49 -08:00
mpage.c
namei.c VFS: don't do protected {sym,hard}links by default 2012-10-26 10:05:07 -07:00
namespace.c userns: Require CAP_SYS_ADMIN for most uses of setns. 2012-12-14 16:12:03 -08:00
no-block.c
open.c vfs: Allow chroot if you have CAP_SYS_CHROOT in your user namespace 2012-11-19 05:59:17 -08:00
pipe.c pipe(2) - race-free error recovery 2012-09-26 21:08:52 -04:00
pnode.c VFS: Make clone_mnt()/copy_tree()/collect_mounts() return errors 2012-07-14 16:37:27 +04:00
pnode.h vfs: Only support slave subtrees across different user namespaces 2012-11-19 05:59:20 -08:00
posix_acl.c userns: Convert vfs posix_acl support to use kuids and kgids 2012-09-18 01:01:35 -07:00
proc_namespace.c get rid of magic in proc_namespace.c 2012-07-14 16:32:48 +04:00
read_write.c compat: fs: Generic compat_sys_sendfile implementation 2012-10-02 21:35:55 -04:00
read_write.h compat: fs: Generic compat_sys_sendfile implementation 2012-10-02 21:35:55 -04:00
readdir.c switch simple cases of fget_light to fdget 2012-09-26 22:20:08 -04:00
select.c switch simple cases of fget_light to fdget 2012-09-26 22:20:08 -04:00
seq_file.c userns: Make seq_file's user namespace accessible 2012-08-14 21:47:55 -07:00
signalfd.c switch simple cases of fget_light to fdget 2012-09-26 22:20:08 -04:00
splice.c switch simple cases of fget_light to fdget 2012-09-26 22:20:08 -04:00
stack.c
stat.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-10-02 20:25:04 -07:00
statfs.c switch simple cases of fget_light to fdget 2012-09-26 22:20:08 -04:00
super.c vfs: drop lock/unlock super 2012-10-09 23:33:39 -04:00
sync.c switch simple cases of fget_light to fdget 2012-09-26 22:20:08 -04:00
timerfd.c switch simple cases of fget_light to fdget 2012-09-26 22:20:08 -04:00
utimes.c switch simple cases of fget_light to fdget 2012-09-26 22:20:08 -04:00
xattr_acl.c userns: Fix posix_acl_file_xattr_userns gid conversion 2012-10-12 13:16:48 -07:00
xattr.c fs, xattr: fix bug when removing a name not in xattr list 2012-10-18 12:35:58 -07:00