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Eric Dumazet c85df6eb6e net/packet: refine check for priv area size
[ Upstream commit eb73190f4f ]

syzbot was able to trick af_packet again [1]

Various commits tried to address the problem in the past,
but failed to take into account V3 header size.

[1]

tpacket_rcv: packet too big, clamped from 72 to 4294967224. macoff=96
BUG: KASAN: use-after-free in prb_run_all_ft_ops net/packet/af_packet.c:1016 [inline]
BUG: KASAN: use-after-free in prb_fill_curr_block.isra.59+0x4e5/0x5c0 net/packet/af_packet.c:1039
Write of size 2 at addr ffff8801cb62000e by task kworker/1:2/2106

CPU: 1 PID: 2106 Comm: kworker/1:2 Not tainted 4.17.0-rc7+ #77
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1b9/0x294 lib/dump_stack.c:113
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
 __asan_report_store2_noabort+0x17/0x20 mm/kasan/report.c:436
 prb_run_all_ft_ops net/packet/af_packet.c:1016 [inline]
 prb_fill_curr_block.isra.59+0x4e5/0x5c0 net/packet/af_packet.c:1039
 __packet_lookup_frame_in_block net/packet/af_packet.c:1094 [inline]
 packet_current_rx_frame net/packet/af_packet.c:1117 [inline]
 tpacket_rcv+0x1866/0x3340 net/packet/af_packet.c:2282
 dev_queue_xmit_nit+0x891/0xb90 net/core/dev.c:2018
 xmit_one net/core/dev.c:3049 [inline]
 dev_hard_start_xmit+0x16b/0xc10 net/core/dev.c:3069
 __dev_queue_xmit+0x2724/0x34c0 net/core/dev.c:3584
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3617
 neigh_resolve_output+0x679/0xad0 net/core/neighbour.c:1358
 neigh_output include/net/neighbour.h:482 [inline]
 ip6_finish_output2+0xc9c/0x2810 net/ipv6/ip6_output.c:120
 ip6_finish_output+0x5fe/0xbc0 net/ipv6/ip6_output.c:154
 NF_HOOK_COND include/linux/netfilter.h:277 [inline]
 ip6_output+0x227/0x9b0 net/ipv6/ip6_output.c:171
 dst_output include/net/dst.h:444 [inline]
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ndisc_send_skb+0x100d/0x1570 net/ipv6/ndisc.c:491
 ndisc_send_ns+0x3c1/0x8d0 net/ipv6/ndisc.c:633
 addrconf_dad_work+0xbef/0x1340 net/ipv6/addrconf.c:4033
 process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145
 worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279
 kthread+0x345/0x410 kernel/kthread.c:240
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412

The buggy address belongs to the page:
page:ffffea00072d8800 count:0 mapcount:-127 mapping:0000000000000000 index:0xffff8801cb620e80
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 ffff8801cb620e80 00000000ffffff80
raw: ffffea00072e3820 ffffea0007132d20 0000000000000002 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801cb61ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801cb61ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801cb620000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                      ^
 ffff8801cb620080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8801cb620100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

Fixes: 2b6867c2ce ("net/packet: fix overflow in check for priv area size")
Fixes: dc808110bb ("packet: handle too big packets for PACKET_V3")
Fixes: f6fb8f100b ("af-packet: TPACKET_V3 flexible buffer implementation.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-11 22:49:20 +02:00
arch powerpc/mm/slice: Fix hugepage allocation at hint address on 8xx 2018-06-05 11:42:00 +02:00
block block: display the correct diskname for bio 2018-05-30 07:52:09 +02:00
certs License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
crypto PKCS#7: fix direct verification of SignerInfo signature 2018-05-30 07:52:01 +02:00
Documentation netdev-FAQ: clarify DaveM's position for stable backports 2018-06-11 22:49:19 +02:00
drivers isdn: eicon: fix a missing-check bug 2018-06-11 22:49:19 +02:00
firmware License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fs btrfs: define SUPER_FLAG_METADUMP_V2 2018-06-11 22:49:18 +02:00
include ipv6: omit traffic class when calculating flow hash 2018-06-11 22:49:19 +02:00
init kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK 2018-02-22 15:42:23 +01:00
ipc ipc/shm: fix shmat() nil address after round-down when remapping 2018-05-30 07:51:49 +02:00
kernel tracing: Make the snapshot trigger work with instances 2018-06-05 11:41:56 +02:00
lib lib/test_kmod.c: fix limit check on number of test devices created 2018-05-30 07:52:14 +02:00
mm mmap: relax file size limit for regular files 2018-06-11 22:49:18 +02:00
net net/packet: refine check for priv area size 2018-06-11 22:49:20 +02:00
samples samples/bpf: Partially fixes the bpf.o build 2018-04-26 11:02:12 +02:00
scripts kconfig: Avoid format overflow warning from GCC 8.1 2018-06-11 22:49:18 +02:00
security selinux: KASAN: slab-out-of-bounds in xattr_getsecurity 2018-06-05 11:41:56 +02:00
sound ASoC: Intel: sst: remove redundant variable dma_dev_name 2018-06-05 11:41:57 +02:00
tools objtool: Fix "noreturn" detection for recursive sibling calls 2018-06-05 11:41:55 +02:00
usr initramfs: fix initramfs rebuilds w/ compression after disabling 2017-11-03 07:39:19 -07:00
virt KVM: arm/arm64: vgic: Add missing irq_lock to vgic_mmio_read_pending 2018-05-30 07:52:15 +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: rpm-pkg: keep spec file until make mrproper 2018-02-13 10:19:46 +01:00
.mailmap .mailmap: Add Maciej W. Rozycki's Imagination e-mail address 2017-11-10 12:16:15 -08:00
COPYING
CREDITS MAINTAINERS: update TPM driver infrastructure changes 2017-11-09 17:58:40 -08:00
Kbuild License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
MAINTAINERS dt-bindings: Document mti,mips-cpc binding 2018-03-15 10:54:35 +01:00
Makefile Linux 4.14.48 2018-06-05 11:42:00 +02:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

Linux kernel
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Please read the Documentation/process/changes.rst file, as it contains the
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