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Eric Dumazet 979f93f1e1 net_sched: ematch: reject invalid TCF_EM_SIMPLE
[ Upstream commit 55cd9f67f1 ]

It is possible for malicious userspace to set TCF_EM_SIMPLE bit
even for matches that should not have this bit set.

This can fool two places using tcf_em_is_simple()

1) tcf_em_tree_destroy() -> memory leak of em->data
   if ops->destroy() is NULL

2) tcf_em_tree_dump() wrongly report/leak 4 low-order bytes
   of a kernel pointer.

BUG: memory leak
unreferenced object 0xffff888121850a40 (size 32):
  comm "syz-executor927", pid 7193, jiffies 4294941655 (age 19.840s)
  hex dump (first 32 bytes):
    00 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000f67036ea>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline]
    [<00000000f67036ea>] slab_post_alloc_hook mm/slab.h:586 [inline]
    [<00000000f67036ea>] slab_alloc mm/slab.c:3320 [inline]
    [<00000000f67036ea>] __do_kmalloc mm/slab.c:3654 [inline]
    [<00000000f67036ea>] __kmalloc_track_caller+0x165/0x300 mm/slab.c:3671
    [<00000000fab0cc8e>] kmemdup+0x27/0x60 mm/util.c:127
    [<00000000d9992e0a>] kmemdup include/linux/string.h:453 [inline]
    [<00000000d9992e0a>] em_nbyte_change+0x5b/0x90 net/sched/em_nbyte.c:32
    [<000000007e04f711>] tcf_em_validate net/sched/ematch.c:241 [inline]
    [<000000007e04f711>] tcf_em_tree_validate net/sched/ematch.c:359 [inline]
    [<000000007e04f711>] tcf_em_tree_validate+0x332/0x46f net/sched/ematch.c:300
    [<000000007a769204>] basic_set_parms net/sched/cls_basic.c:157 [inline]
    [<000000007a769204>] basic_change+0x1d7/0x5f0 net/sched/cls_basic.c:219
    [<00000000e57a5997>] tc_new_tfilter+0x566/0xf70 net/sched/cls_api.c:2104
    [<0000000074b68559>] rtnetlink_rcv_msg+0x3b2/0x4b0 net/core/rtnetlink.c:5415
    [<00000000b7fe53fb>] netlink_rcv_skb+0x61/0x170 net/netlink/af_netlink.c:2477
    [<00000000e83a40d0>] rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5442
    [<00000000d62ba933>] netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
    [<00000000d62ba933>] netlink_unicast+0x223/0x310 net/netlink/af_netlink.c:1328
    [<0000000088070f72>] netlink_sendmsg+0x2c0/0x570 net/netlink/af_netlink.c:1917
    [<00000000f70b15ea>] sock_sendmsg_nosec net/socket.c:639 [inline]
    [<00000000f70b15ea>] sock_sendmsg+0x54/0x70 net/socket.c:659
    [<00000000ef95a9be>] ____sys_sendmsg+0x2d0/0x300 net/socket.c:2330
    [<00000000b650f1ab>] ___sys_sendmsg+0x8a/0xd0 net/socket.c:2384
    [<0000000055bfa74a>] __sys_sendmsg+0x80/0xf0 net/socket.c:2417
    [<000000002abac183>] __do_sys_sendmsg net/socket.c:2426 [inline]
    [<000000002abac183>] __se_sys_sendmsg net/socket.c:2424 [inline]
    [<000000002abac183>] __x64_sys_sendmsg+0x23/0x30 net/socket.c:2424

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot+03c4738ed29d5d366ddf@syzkaller.appspotmail.com
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-01 09:37:05 +00:00
arch mm/memory_hotplug: shrink zones when offlining memory 2020-01-29 16:43:27 +01:00
block block: don't use bio->bi_vcnt to figure out segment number 2020-01-27 14:50:23 +01:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto crypto: tgr192 - fix unaligned memory access 2020-01-27 14:50:13 +01:00
Documentation Documentation: Document arm64 kpti control 2020-01-29 16:43:19 +01:00
drivers zd1211rw: fix storage endpoint lookup 2020-02-01 09:37:05 +00:00
firmware Fix built-in early-load Intel microcode alignment 2020-01-23 08:21:29 +01:00
fs cifs: Fix memory allocation in __smb2_handle_cancelled_cmd() 2020-02-01 09:37:04 +00:00
include USB: serial: ir-usb: fix link-speed handling 2020-02-01 09:37:01 +00:00
init fork: fix some -Wmissing-prototypes warnings 2019-12-05 09:21:04 +01:00
ipc ipc/mqueue.c: only perform resource calculation if user valid 2019-08-06 19:06:52 +02:00
kernel mm/memory_hotplug: shrink zones when offlining memory 2020-01-29 16:43:27 +01:00
lib Partially revert "kfifo: fix kfifo_alloc() and kfifo_init()" 2020-01-27 14:51:08 +01:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm mm/memory_hotplug: shrink zones when offlining memory 2020-01-29 16:43:27 +01:00
net net_sched: ematch: reject invalid TCF_EM_SIMPLE 2020-02-01 09:37:05 +00:00
samples samples/bpf: Fix broken xdp_rxq_info due to map order assumptions 2020-01-27 14:51:22 +01:00
scripts ARM: 8950/1: ftrace/recordmcount: filter relocation types 2020-01-29 16:43:19 +01:00
security keys: Timestamp new keys 2020-01-27 14:50:23 +01:00
sound ASoC: sun4i-i2s: RX and TX counter registers are swapped 2020-01-27 14:51:05 +01:00
tools tools: bpftool: fix format strings and arguments for jsonw_printf() 2020-01-27 14:51:05 +01:00
usr kbuild: clean compressed initramfs image 2019-10-07 18:57:16 +02:00
virt KVM: arm/arm64: vgic: Don't rely on the wrong pending table 2019-12-13 08:52:45 +01:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS USB: rio500: Remove Rio 500 kernel driver 2019-10-17 13:44:47 -07:00
Makefile Linux 4.19.100 2020-01-29 16:43:27 +01:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

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

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

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.