linux/drivers/block
Eric W. Biederman 38bf195398 connector/userns: replace netlink uses of cap_raised() with capable()
In 2009 Philip Reiser notied that a few users of netlink connector
interface needed a capability check and added the idiom
cap_raised(nsp->eff_cap, CAP_SYS_ADMIN) to a few of them, on the premise
that netlink was asynchronous.

In 2011 Patrick McHardy noticed we were being silly because netlink is
synchronous and removed eff_cap from the netlink_skb_params and changed
the idiom to cap_raised(current_cap(), CAP_SYS_ADMIN).

Looking at those spots with a fresh eye we should be calling
capable(CAP_SYS_ADMIN).  The only reason I can see for not calling capable
is that it once appeared we were not in the same task as the caller which
would have made calling capable() impossible.

In the initial user_namespace the only difference between between
cap_raised(current_cap(), CAP_SYS_ADMIN) and capable(CAP_SYS_ADMIN) are a
few sanity checks and the fact that capable(CAP_SYS_ADMIN) sets
PF_SUPERPRIV if we use the capability.

Since we are going to be using root privilege setting PF_SUPERPRIV seems
the right thing to do.

The motivation for this that patch is that in a child user namespace
cap_raised(current_cap(),...) tests your capabilities with respect to that
child user namespace not capabilities in the initial user namespace and
thus will allow processes that should be unprivielged to use the kernel
services that are only protected with cap_raised(current_cap(),..).

To fix possible user_namespace issues and to just clean up the code
replace cap_raised(current_cap(), CAP_SYS_ADMIN) with
capable(CAP_SYS_ADMIN).

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Acked-by: Andrew G. Morgan <morgan@kernel.org>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Cc: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-10 23:21:39 -04:00
..
aoe switch device_get_devnode() and ->devnode() to umode_t * 2012-01-03 22:54:55 -05:00
drbd connector/userns: replace netlink uses of cap_raised() with capable() 2012-05-10 23:21:39 -04:00
mtip32xx block: mtip32xx: remove HOTPLUG_PCI_PCIE dependancy 2012-04-12 08:47:05 +02:00
paride paride/pcd: fix bool verbose module parameter. 2012-01-13 09:32:26 +10:30
xen-blkback xen/blkback: Fix warning error. 2012-04-18 15:54:08 -04:00
amiflop.c fs: move code out of buffer.c 2012-01-03 22:54:07 -05:00
ataflop.c
brd.c block: remove the second argument of k[un]map_atomic() 2012-03-20 21:48:16 +08:00
cciss_cmd.h
cciss_scsi.c cciss: Fix scsi tape io with more than 255 scatter gather elements 2012-03-22 21:40:09 +01:00
cciss_scsi.h
cciss.c block: add and use scsi_blk_cmd_ioctl 2012-01-14 15:07:24 -08:00
cciss.h
cpqarray.c
cpqarray.h
cryptoloop.c
DAC960.c drivers/block/DAC960: fix -Wuninitialized warning 2012-03-02 10:48:35 +01:00
DAC960.h
floppy.c x86: Remove the ancient and deprecated disable_hlt() and enable_hlt() facility 2012-03-30 08:50:27 +02:00
hd.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
ida_cmd.h
ida_ioctl.h
Kconfig usb/ub: deprecate & schedule for removal the "Low Performance USB Block" driver 2012-03-16 13:30:10 -07:00
loop.c block: remove the second argument of k[un]map_atomic() 2012-03-20 21:48:16 +08:00
Makefile Merge git://git.infradead.org/users/willy/linux-nvme 2012-01-18 12:34:09 -08:00
mg_disk.c
nbd.c Merge branch 'akpm' (Andrew's patch-bomb) 2012-03-28 17:19:28 -07:00
nvme.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2012-03-20 21:12:50 -07:00
osdblk.c
pktcdvd.c block: remove the second argument of k[un]map_atomic() 2012-03-20 21:48:16 +08:00
ps3disk.c
ps3vram.c
rbd_types.h rbd: small changes 2012-03-22 10:47:50 -05:00
rbd.c rbd: move snap_rwsem to the device, rename to header_rwsem 2012-03-22 10:47:52 -05:00
smart1,2.h
sunvdc.c powerpc+sparc/vio: Modernize driver registration 2012-03-28 11:33:24 +11:00
swim3.c block/swim3: Locking fixes 2011-12-12 12:42:12 +01:00
swim_asm.S
swim.c
sx8.c block, sx8: fix pointer math issue getting fw version 2012-03-03 19:44:39 +01:00
ub.c usb/ub: deprecate & schedule for removal the "Low Performance USB Block" driver 2012-03-16 13:30:10 -07:00
umem.c
umem.h
virtio_blk.c virtio: fixes on top of 3.4-rc2 2012-04-16 18:34:12 -07:00
xd.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
xd.h
xen-blkfront.c Merge branch 'for-3.4/drivers' of git://git.kernel.dk/linux-block 2012-04-13 18:45:13 -07:00
xsysace.c block: xsysace: Don't use NO_IRQ 2012-01-05 08:34:29 +01:00
z2ram.c