linux-stable.git/net/bridge, branch v3.16.74 Linux kernel stable tree netfilter: ebtables: CONFIG_COMPAT: reject trailing data after last rule 2019-09-23T20:12:03+00:00 Florian Westphal fw@strlen.de 2019-05-05T16:47:33+00:00 c140ca37d8f979b0ddb721b3fc7d6e16ae1305a8 commit 680f6af5337c98d116e4f127cea7845339dba8da upstream. If userspace provides a rule blob with trailing data after last target, we trigger a splat, then convert ruleset to 64bit format (with trailing data), then pass that to do_replace_finish() which then returns -EINVAL. Erroring out right away avoids the splat plus unneeded translation and error unwind. Fixes: 81e675c227ec ("netfilter: ebtables: add CONFIG_COMPAT support") Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 680f6af5337c98d116e4f127cea7845339dba8da upstream.

If userspace provides a rule blob with trailing data after last target,
we trigger a splat, then convert ruleset to 64bit format (with trailing
data), then pass that to do_replace_finish() which then returns -EINVAL.

Erroring out right away avoids the splat plus unneeded translation and
error unwind.

Fixes: 81e675c227ec ("netfilter: ebtables: add CONFIG_COMPAT support")
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
netfilter: ebtables: CONFIG_COMPAT: drop a bogus WARN_ON 2019-08-13T11:39:13+00:00 Florian Westphal fw@strlen.de 2019-04-14T22:43:00+00:00 de190e903119b4a86e0745efed2e0caee47bf605 commit 7caa56f006e9d712b44f27b32520c66420d5cbc6 upstream. It means userspace gave us a ruleset where there is some other data after the ebtables target but before the beginning of the next rule. Fixes: 81e675c227ec ("netfilter: ebtables: add CONFIG_COMPAT support") Reported-by: syzbot+659574e7bcc7f7eb4df7@syzkaller.appspotmail.com Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 7caa56f006e9d712b44f27b32520c66420d5cbc6 upstream.

It means userspace gave us a ruleset where there is some other
data after the ebtables target but before the beginning of the next rule.

Fixes: 81e675c227ec ("netfilter: ebtables: add CONFIG_COMPAT support")
Reported-by: syzbot+659574e7bcc7f7eb4df7@syzkaller.appspotmail.com
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
net: bridge: multicast: use rcu to access port list from br_multicast_start_querier 2019-08-13T11:39:05+00:00 Nikolay Aleksandrov nikolay@cumulusnetworks.com 2019-04-11T12:08:25+00:00 83a138f5176cc8ca9e1d5c970e86fba926f76fc2 commit c5b493ce192bd7a4e7bd073b5685aad121eeef82 upstream. br_multicast_start_querier() walks over the port list but it can be called from a timer with only multicast_lock held which doesn't protect the port list, so use RCU to walk over it. Fixes: c83b8fab06fc ("bridge: Restart queries when last querier expires") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit c5b493ce192bd7a4e7bd073b5685aad121eeef82 upstream.

br_multicast_start_querier() walks over the port list but it can be
called from a timer with only multicast_lock held which doesn't protect
the port list, so use RCU to walk over it.

Fixes: c83b8fab06fc ("bridge: Restart queries when last querier expires")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
netfilter: bridge: set skb transport_header before entering NF_INET_PRE_ROUTING 2019-08-13T11:38:43+00:00 Xin Long lucien.xin@gmail.com 2019-03-13T08:33:29+00:00 5d17c80f28dc9041b57aaa527057c5ad7b68cc41 commit e166e4fdaced850bee3d5ee12a5740258fb30587 upstream. Since Commit 21d1196a35f5 ("ipv4: set transport header earlier"), skb->transport_header has been always set before entering INET netfilter. This patch is to set skb->transport_header for bridge before entering INET netfilter by bridge-nf-call-iptables. It also fixes an issue that sctp_error() couldn't compute a right csum due to unset skb->transport_header. Fixes: e6d8b64b34aa ("net: sctp: fix and consolidate SCTP checksumming code") Reported-by: Li Shuang <shuali@redhat.com> Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> [bwh: Backported to 3.16: adjust filenames, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit e166e4fdaced850bee3d5ee12a5740258fb30587 upstream.

Since Commit 21d1196a35f5 ("ipv4: set transport header earlier"),
skb->transport_header has been always set before entering INET
netfilter. This patch is to set skb->transport_header for bridge
before entering INET netfilter by bridge-nf-call-iptables.

It also fixes an issue that sctp_error() couldn't compute a right
csum due to unset skb->transport_header.

Fixes: e6d8b64b34aa ("net: sctp: fix and consolidate SCTP checksumming code")
Reported-by: Li Shuang <shuali@redhat.com>
Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
[bwh: Backported to 3.16: adjust filenames, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
net: bridge: Fix ethernet header pointer before check skb forwardable 2019-05-02T20:41:25+00:00 Yunjian Wang wangyunjian@huawei.com 2019-01-17T01:46:41+00:00 037cdae7624824a14f850d6fccd7b082907be72a commit 28c1382fa28f2e2d9d0d6f25ae879b5af2ecbd03 upstream. The skb header should be set to ethernet header before using is_skb_forwardable. Because the ethernet header length has been considered in is_skb_forwardable(including dev->hard_header_len length). To reproduce the issue: 1, add 2 ports on linux bridge br using following commands: $ brctl addbr br $ brctl addif br eth0 $ brctl addif br eth1 2, the MTU of eth0 and eth1 is 1500 3, send a packet(Data 1480, UDP 8, IP 20, Ethernet 14, VLAN 4) from eth0 to eth1 So the expect result is packet larger than 1500 cannot pass through eth0 and eth1. But currently, the packet passes through success, it means eth1's MTU limit doesn't take effect. Fixes: f6367b4660dd ("bridge: use is_skb_forwardable in forward path") Cc: bridge@lists.linux-foundation.org Cc: Nkolay Aleksandrov <nikolay@cumulusnetworks.com> Cc: Roopa Prabhu <roopa@cumulusnetworks.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Yunjian Wang <wangyunjian@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: - br_dev_queue_push_xmit() has to call nf_bridge_maybe_copy_header() before pushing the Ethernet header - adjust context, indentation] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 28c1382fa28f2e2d9d0d6f25ae879b5af2ecbd03 upstream.

The skb header should be set to ethernet header before using
is_skb_forwardable. Because the ethernet header length has been
considered in is_skb_forwardable(including dev->hard_header_len
length).

To reproduce the issue:
1, add 2 ports on linux bridge br using following commands:
$ brctl addbr br
$ brctl addif br eth0
$ brctl addif br eth1
2, the MTU of eth0 and eth1 is 1500
3, send a packet(Data 1480, UDP 8, IP 20, Ethernet 14, VLAN 4)
from eth0 to eth1

So the expect result is packet larger than 1500 cannot pass through
eth0 and eth1. But currently, the packet passes through success, it
means eth1's MTU limit doesn't take effect.

Fixes: f6367b4660dd ("bridge: use is_skb_forwardable in forward path")
Cc: bridge@lists.linux-foundation.org
Cc: Nkolay Aleksandrov <nikolay@cumulusnetworks.com>
Cc: Roopa Prabhu <roopa@cumulusnetworks.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16:
 - br_dev_queue_push_xmit() has to call nf_bridge_maybe_copy_header()
   before pushing the Ethernet header
 - adjust context, indentation]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
netfilter: ebtables: handle string from userspace with care 2018-10-21T07:46:12+00:00 Paolo Abeni pabeni@redhat.com 2018-04-27T08:45:31+00:00 9257151618971b19a555c8f7dc767a6ef7198221 commit 94c752f99954797da583a84c4907ff19e92550a4 upstream. strlcpy() can't be safely used on a user-space provided string, as it can try to read beyond the buffer's end, if the latter is not NULL terminated. Leveraging the above, syzbot has been able to trigger the following splat: BUG: KASAN: stack-out-of-bounds in strlcpy include/linux/string.h:300 [inline] BUG: KASAN: stack-out-of-bounds in compat_mtw_from_user net/bridge/netfilter/ebtables.c:1957 [inline] BUG: KASAN: stack-out-of-bounds in ebt_size_mwt net/bridge/netfilter/ebtables.c:2059 [inline] BUG: KASAN: stack-out-of-bounds in size_entry_mwt net/bridge/netfilter/ebtables.c:2155 [inline] BUG: KASAN: stack-out-of-bounds in compat_copy_entries+0x96c/0x14a0 net/bridge/netfilter/ebtables.c:2194 Write of size 33 at addr ffff8801b0abf888 by task syz-executor0/4504 CPU: 0 PID: 4504 Comm: syz-executor0 Not tainted 4.17.0-rc2+ #40 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 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 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267 memcpy+0x37/0x50 mm/kasan/kasan.c:303 strlcpy include/linux/string.h:300 [inline] compat_mtw_from_user net/bridge/netfilter/ebtables.c:1957 [inline] ebt_size_mwt net/bridge/netfilter/ebtables.c:2059 [inline] size_entry_mwt net/bridge/netfilter/ebtables.c:2155 [inline] compat_copy_entries+0x96c/0x14a0 net/bridge/netfilter/ebtables.c:2194 compat_do_replace+0x483/0x900 net/bridge/netfilter/ebtables.c:2285 compat_do_ebt_set_ctl+0x2ac/0x324 net/bridge/netfilter/ebtables.c:2367 compat_nf_sockopt net/netfilter/nf_sockopt.c:144 [inline] compat_nf_setsockopt+0x9b/0x140 net/netfilter/nf_sockopt.c:156 compat_ip_setsockopt+0xff/0x140 net/ipv4/ip_sockglue.c:1279 inet_csk_compat_setsockopt+0x97/0x120 net/ipv4/inet_connection_sock.c:1041 compat_tcp_setsockopt+0x49/0x80 net/ipv4/tcp.c:2901 compat_sock_common_setsockopt+0xb4/0x150 net/core/sock.c:3050 __compat_sys_setsockopt+0x1ab/0x7c0 net/compat.c:403 __do_compat_sys_setsockopt net/compat.c:416 [inline] __se_compat_sys_setsockopt net/compat.c:413 [inline] __ia32_compat_sys_setsockopt+0xbd/0x150 net/compat.c:413 do_syscall_32_irqs_on arch/x86/entry/common.c:323 [inline] do_fast_syscall_32+0x345/0xf9b arch/x86/entry/common.c:394 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7fb3cb9 RSP: 002b:00000000fff0c26c EFLAGS: 00000282 ORIG_RAX: 000000000000016e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000000 RDX: 0000000000000080 RSI: 0000000020000300 RDI: 00000000000005f4 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 The buggy address belongs to the page: page:ffffea0006c2afc0 count:0 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0x2fffc0000000000() raw: 02fffc0000000000 0000000000000000 0000000000000000 00000000ffffffff raw: 0000000000000000 ffffea0006c20101 0000000000000000 0000000000000000 page dumped because: kasan: bad access detected Fix the issue replacing the unsafe function with strscpy() and taking care of possible errors. Fixes: 81e675c227ec ("netfilter: ebtables: add CONFIG_COMPAT support") Reported-and-tested-by: syzbot+4e42a04e0bc33cb6c087@syzkaller.appspotmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 94c752f99954797da583a84c4907ff19e92550a4 upstream.

strlcpy() can't be safely used on a user-space provided string,
as it can try to read beyond the buffer's end, if the latter is
not NULL terminated.

Leveraging the above, syzbot has been able to trigger the following
splat:

BUG: KASAN: stack-out-of-bounds in strlcpy include/linux/string.h:300
[inline]
BUG: KASAN: stack-out-of-bounds in compat_mtw_from_user
net/bridge/netfilter/ebtables.c:1957 [inline]
BUG: KASAN: stack-out-of-bounds in ebt_size_mwt
net/bridge/netfilter/ebtables.c:2059 [inline]
BUG: KASAN: stack-out-of-bounds in size_entry_mwt
net/bridge/netfilter/ebtables.c:2155 [inline]
BUG: KASAN: stack-out-of-bounds in compat_copy_entries+0x96c/0x14a0
net/bridge/netfilter/ebtables.c:2194
Write of size 33 at addr ffff8801b0abf888 by task syz-executor0/4504

CPU: 0 PID: 4504 Comm: syz-executor0 Not tainted 4.17.0-rc2+ #40
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
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
  check_memory_region_inline mm/kasan/kasan.c:260 [inline]
  check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
  memcpy+0x37/0x50 mm/kasan/kasan.c:303
  strlcpy include/linux/string.h:300 [inline]
  compat_mtw_from_user net/bridge/netfilter/ebtables.c:1957 [inline]
  ebt_size_mwt net/bridge/netfilter/ebtables.c:2059 [inline]
  size_entry_mwt net/bridge/netfilter/ebtables.c:2155 [inline]
  compat_copy_entries+0x96c/0x14a0 net/bridge/netfilter/ebtables.c:2194
  compat_do_replace+0x483/0x900 net/bridge/netfilter/ebtables.c:2285
  compat_do_ebt_set_ctl+0x2ac/0x324 net/bridge/netfilter/ebtables.c:2367
  compat_nf_sockopt net/netfilter/nf_sockopt.c:144 [inline]
  compat_nf_setsockopt+0x9b/0x140 net/netfilter/nf_sockopt.c:156
  compat_ip_setsockopt+0xff/0x140 net/ipv4/ip_sockglue.c:1279
  inet_csk_compat_setsockopt+0x97/0x120 net/ipv4/inet_connection_sock.c:1041
  compat_tcp_setsockopt+0x49/0x80 net/ipv4/tcp.c:2901
  compat_sock_common_setsockopt+0xb4/0x150 net/core/sock.c:3050
  __compat_sys_setsockopt+0x1ab/0x7c0 net/compat.c:403
  __do_compat_sys_setsockopt net/compat.c:416 [inline]
  __se_compat_sys_setsockopt net/compat.c:413 [inline]
  __ia32_compat_sys_setsockopt+0xbd/0x150 net/compat.c:413
  do_syscall_32_irqs_on arch/x86/entry/common.c:323 [inline]
  do_fast_syscall_32+0x345/0xf9b arch/x86/entry/common.c:394
  entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7fb3cb9
RSP: 002b:00000000fff0c26c EFLAGS: 00000282 ORIG_RAX: 000000000000016e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000080 RSI: 0000000020000300 RDI: 00000000000005f4
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea0006c2afc0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 ffffea0006c20101 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Fix the issue replacing the unsafe function with strscpy() and
taking care of possible errors.

Fixes: 81e675c227ec ("netfilter: ebtables: add CONFIG_COMPAT support")
Reported-and-tested-by: syzbot+4e42a04e0bc33cb6c087@syzkaller.appspotmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
netfilter: bridge: ebt_among: add more missing match size checks 2018-06-16T21:22:37+00:00 Florian Westphal fw@strlen.de 2018-03-09T13:27:31+00:00 491de848db8e7a3484e03b854d7e27ad5d8d6442 commit c8d70a700a5b486bfa8e5a7d33d805389f6e59f9 upstream. ebt_among is special, it has a dynamic match size and is exempt from the central size checks. commit c4585a2823edf ("bridge: ebt_among: add missing match size checks") added validation for pool size, but missed fact that the macros ebt_among_wh_src/dst can already return out-of-bound result because they do not check value of wh_src/dst_ofs (an offset) vs. the size of the match that userspace gave to us. v2: check that offset has correct alignment. Paolo Abeni points out that we should also check that src/dst wormhash arrays do not overlap, and src + length lines up with start of dst (or vice versa). v3: compact wormhash_sizes_valid() part NB: Fixes tag is intentionally wrong, this bug exists from day one when match was added for 2.6 kernel. Tag is there so stable maintainers will notice this one too. Tested with same rules from the earlier patch. Fixes: c4585a2823edf ("bridge: ebt_among: add missing match size checks") Reported-by: <syzbot+bdabab6f1983a03fc009@syzkaller.appspotmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit c8d70a700a5b486bfa8e5a7d33d805389f6e59f9 upstream.

ebt_among is special, it has a dynamic match size and is exempt
from the central size checks.

commit c4585a2823edf ("bridge: ebt_among: add missing match size checks")
added validation for pool size, but missed fact that the macros
ebt_among_wh_src/dst can already return out-of-bound result because
they do not check value of wh_src/dst_ofs (an offset) vs. the size
of the match that userspace gave to us.

v2:
check that offset has correct alignment.
Paolo Abeni points out that we should also check that src/dst
wormhash arrays do not overlap, and src + length lines up with
start of dst (or vice versa).
v3: compact wormhash_sizes_valid() part

NB: Fixes tag is intentionally wrong, this bug exists from day
one when match was added for 2.6 kernel. Tag is there so stable
maintainers will notice this one too.

Tested with same rules from the earlier patch.

Fixes: c4585a2823edf ("bridge: ebt_among: add missing match size checks")
Reported-by: <syzbot+bdabab6f1983a03fc009@syzkaller.appspotmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
netfilter: bridge: ebt_among: add missing match size checks 2018-06-16T21:22:37+00:00 Florian Westphal fw@strlen.de 2018-02-19T02:01:45+00:00 90ee942faa9d07b3d9b92f92d83948295c390600 commit c4585a2823edf4d1326da44d1524ecbfda26bb37 upstream. ebt_among is special, it has a dynamic match size and is exempt from the central size checks. Therefore it must check that the size of the match structure provided from userspace is sane by making sure em->match_size is at least the minimum size of the expected structure. The module has such a check, but its only done after accessing a structure that might be out of bounds. tested with: ebtables -A INPUT ... \ --among-dst fe:fe:fe:fe:fe:fe --among-dst fe:fe:fe:fe:fe:fe --among-src fe:fe:fe:fe:ff:f,fe:fe:fe:fe:fe:fb,fe:fe:fe:fe:fc:fd,fe:fe:fe:fe:fe:fd,fe:fe:fe:fe:fe:fe --among-src fe:fe:fe:fe:ff:f,fe:fe:fe:fe:fe:fa,fe:fe:fe:fe:fe:fd,fe:fe:fe:fe:fe:fe,fe:fe:fe:fe:fe:fe Reported-by: <syzbot+fe0b19af568972814355@syzkaller.appspotmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit c4585a2823edf4d1326da44d1524ecbfda26bb37 upstream.

ebt_among is special, it has a dynamic match size and is exempt
from the central size checks.

Therefore it must check that the size of the match structure
provided from userspace is sane by making sure em->match_size
is at least the minimum size of the expected structure.

The module has such a check, but its only done after accessing
a structure that might be out of bounds.

tested with: ebtables -A INPUT ... \
--among-dst fe:fe:fe:fe:fe:fe
--among-dst fe:fe:fe:fe:fe:fe --among-src fe:fe:fe:fe:ff:f,fe:fe:fe:fe:fe:fb,fe:fe:fe:fe:fc:fd,fe:fe:fe:fe:fe:fd,fe:fe:fe:fe:fe:fe
--among-src fe:fe:fe:fe:ff:f,fe:fe:fe:fe:fe:fa,fe:fe:fe:fe:fe:fd,fe:fe:fe:fe:fe:fe,fe:fe:fe:fe:fe:fe

Reported-by: <syzbot+fe0b19af568972814355@syzkaller.appspotmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
bridge: check brport attr show in brport_show 2018-06-16T21:22:13+00:00 Xin Long lucien.xin@gmail.com 2018-02-12T09:15:40+00:00 8f069d6a9b383380970bcb0b75282686904499eb commit 1b12580af1d0677c3c3a19e35bfe5d59b03f737f upstream. Now br_sysfs_if file flush doesn't have attr show. To read it will cause kernel panic after users chmod u+r this file. Xiong found this issue when running the commands: ip link add br0 type bridge ip link add type veth ip link set veth0 master br0 chmod u+r /sys/devices/virtual/net/veth0/brport/flush timeout 3 cat /sys/devices/virtual/net/veth0/brport/flush kernel crashed with NULL a pointer dereference call trace. This patch is to fix it by return -EINVAL when brport_attr->show is null, just the same as the check for brport_attr->store in brport_store(). Fixes: 9cf637473c85 ("bridge: add sysfs hook to flush forwarding table") Reported-by: Xiong Zhou <xzhou@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 1b12580af1d0677c3c3a19e35bfe5d59b03f737f upstream.

Now br_sysfs_if file flush doesn't have attr show. To read it will
cause kernel panic after users chmod u+r this file.

Xiong found this issue when running the commands:

  ip link add br0 type bridge
  ip link add type veth
  ip link set veth0 master br0
  chmod u+r /sys/devices/virtual/net/veth0/brport/flush
  timeout 3 cat /sys/devices/virtual/net/veth0/brport/flush

kernel crashed with NULL a pointer dereference call trace.

This patch is to fix it by return -EINVAL when brport_attr->show
is null, just the same as the check for brport_attr->store in
brport_store().

Fixes: 9cf637473c85 ("bridge: add sysfs hook to flush forwarding table")
Reported-by: Xiong Zhou <xzhou@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
netfilter: ebtables: fix erroneous reject of last rule 2018-06-16T21:21:30+00:00 Florian Westphal fw@strlen.de 2018-03-08T11:54:19+00:00 68edcec690a62dfc46c4061dab83c08573427e6b commit 932909d9b28d27e807ff8eecb68c7748f6701628 upstream. The last rule in the blob has next_entry offset that is same as total size. This made "ebtables32 -A OUTPUT -d de:ad:be:ef:01:02" fail on 64 bit kernel. Fixes: b71812168571fa ("netfilter: ebtables: CONFIG_COMPAT: don't trust userland offsets") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 932909d9b28d27e807ff8eecb68c7748f6701628 upstream.

The last rule in the blob has next_entry offset that is same as total size.
This made "ebtables32 -A OUTPUT -d de:ad:be:ef:01:02" fail on 64 bit kernel.

Fixes: b71812168571fa ("netfilter: ebtables: CONFIG_COMPAT: don't trust userland offsets")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>