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Alexey Kodanev 4e14bf4236 macvlan: fix use-after-free in macvlan_common_newlink()
The following use-after-free was reported by KASan when running
LTP macvtap01 test on 4.16-rc2:

[10642.528443] BUG: KASAN: use-after-free in
               macvlan_common_newlink+0x12ef/0x14a0 [macvlan]
[10642.626607] Read of size 8 at addr ffff880ba49f2100 by task ip/18450
...
[10642.963873] Call Trace:
[10642.994352]  dump_stack+0x5c/0x7c
[10643.035325]  print_address_description+0x75/0x290
[10643.092938]  kasan_report+0x28d/0x390
[10643.137971]  ? macvlan_common_newlink+0x12ef/0x14a0 [macvlan]
[10643.207963]  macvlan_common_newlink+0x12ef/0x14a0 [macvlan]
[10643.275978]  macvtap_newlink+0x171/0x260 [macvtap]
[10643.334532]  rtnl_newlink+0xd4f/0x1300
...
[10646.256176] Allocated by task 18450:
[10646.299964]  kasan_kmalloc+0xa6/0xd0
[10646.343746]  kmem_cache_alloc_trace+0xf1/0x210
[10646.397826]  macvlan_common_newlink+0x6de/0x14a0 [macvlan]
[10646.464386]  macvtap_newlink+0x171/0x260 [macvtap]
[10646.522728]  rtnl_newlink+0xd4f/0x1300
...
[10647.022028] Freed by task 18450:
[10647.061549]  __kasan_slab_free+0x138/0x180
[10647.111468]  kfree+0x9e/0x1c0
[10647.147869]  macvlan_port_destroy+0x3db/0x650 [macvlan]
[10647.211411]  rollback_registered_many+0x5b9/0xb10
[10647.268715]  rollback_registered+0xd9/0x190
[10647.319675]  register_netdevice+0x8eb/0xc70
[10647.370635]  macvlan_common_newlink+0xe58/0x14a0 [macvlan]
[10647.437195]  macvtap_newlink+0x171/0x260 [macvtap]

Commit d02fd6e7d2 ("macvlan: Fix one possible double free") handles
the case when register_netdevice() invokes ndo_uninit() on error and
as a result free the port. But 'macvlan_port_get_rtnl(dev))' check
(returns dev->rx_handler_data), which was added by this commit in order
to prevent double free, is not quite correct:

* for macvlan it always returns NULL because 'lowerdev' is the one that
  was used to register rx handler (port) in macvlan_port_create() as
  well as to unregister it in macvlan_port_destroy().
* for macvtap it always returns a valid pointer because macvtap registers
  its own rx handler before macvlan_common_newlink().

Fixes: d02fd6e7d2 ("macvlan: Fix one possible double free")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-23 10:48:10 -05:00
arch Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-02-18 12:56:41 -08:00
block blk: optimization for classic polling 2018-02-13 09:12:04 -07:00
certs License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2018-02-12 08:57:21 -08:00
Documentation Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-02-19 11:58:19 -08:00
drivers macvlan: fix use-after-free in macvlan_common_newlink() 2018-02-23 10:48:10 -05:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs for-4.16-rc1-tag 2018-02-16 09:26:18 -08:00
include Various fixes across the tree, the shortlog basically says it all: 2018-02-22 15:17:01 -05:00
init membarrier: Provide core serializing command, *_SYNC_CORE 2018-02-05 21:35:03 +01:00
ipc vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2018-02-21 15:37:37 -05:00
lib dma-direct: comment the dma_direct_free calling convention 2018-02-12 15:59:07 +00:00
LICENSES LICENSES: Add MPL-1.1 license 2018-01-06 10:59:44 -07:00
mm mm: hide a #warning for COMPILE_TEST 2018-02-16 09:41:36 -08:00
net rxrpc: Fix send in rxrpc_send_data_packet() 2018-02-22 15:37:47 -05:00
samples sample/bpf: fix erspan metadata 2018-02-06 11:32:49 -05:00
scripts Kbuild updates for v4.16 (2nd) 2018-02-09 19:32:41 -08:00
security vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
sound ALSA: hda/realtek: PCI quirk for Fujitsu U7x7 2018-02-14 12:02:26 +01:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2018-02-21 15:37:37 -05:00
usr initramfs: fix initramfs rebuilds w/ compression after disabling 2017-11-03 07:39:19 -07:00
virt vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore .gitignore: ignore ASN.1 auto generated files 2018-02-14 21:05:38 +01:00
.mailmap mailmap: update Mark Yao's email address 2018-01-04 16:45:09 -08:00
COPYING
CREDITS MAINTAINERS: update TPM driver infrastructure changes 2017-11-09 17:58:40 -08:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
MAINTAINERS Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-02-14 17:02:15 -08:00
Makefile Linux 4.16-rc2 2018-02-18 17:29:42 -08:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.