linux-stable.git/net/dccp, branch linux-4.9.y Linux kernel stable tree dccp: don't duplicate ccid when cloning dccp sock 2021-09-22T09:43:09+00:00 Lin, Zhenpeng zplin@psu.edu 2021-09-08T03:40:59+00:00 40ea36ffa7207456c3f155bbab76754d3f37ce04 commit d9ea761fdd197351890418acd462c51f241014a7 upstream. Commit 2677d2067731 ("dccp: don't free ccid2_hc_tx_sock ...") fixed a UAF but reintroduced CVE-2017-6074. When the sock is cloned, two dccps_hc_tx_ccid will reference to the same ccid. So one can free the ccid object twice from two socks after cloning. This issue was found by "Hadar Manor" as well and assigned with CVE-2020-16119, which was fixed in Ubuntu's kernel. So here I port the patch from Ubuntu to fix it. The patch prevents cloned socks from referencing the same ccid. Fixes: 2677d2067731410 ("dccp: don't free ccid2_hc_tx_sock ...") Signed-off-by: Zhenpeng Lin <zplin@psu.edu> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit d9ea761fdd197351890418acd462c51f241014a7 upstream.

Commit 2677d2067731 ("dccp: don't free ccid2_hc_tx_sock ...") fixed
a UAF but reintroduced CVE-2017-6074.

When the sock is cloned, two dccps_hc_tx_ccid will reference to the
same ccid. So one can free the ccid object twice from two socks after
cloning.

This issue was found by "Hadar Manor" as well and assigned with
CVE-2020-16119, which was fixed in Ubuntu's kernel. So here I port
the patch from Ubuntu to fix it.

The patch prevents cloned socks from referencing the same ccid.

Fixes: 2677d2067731410 ("dccp: don't free ccid2_hc_tx_sock ...")
Signed-off-by: Zhenpeng Lin <zplin@psu.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dccp: add do-while-0 stubs for dccp_pr_debug macros 2021-08-26T12:37:27+00:00 Randy Dunlap rdunlap@infradead.org 2021-08-08T23:04:40+00:00 adc3308f9af34e0a16cbad19dfe000983d4fe93b [ Upstream commit 86aab09a4870bb8346c9579864588c3d7f555299 ] GCC complains about empty macros in an 'if' statement, so convert them to 'do {} while (0)' macros. Fixes these build warnings: net/dccp/output.c: In function 'dccp_xmit_packet': ../net/dccp/output.c:283:71: warning: suggest braces around empty body in an 'if' statement [-Wempty-body] 283 | dccp_pr_debug("transmit_skb() returned err=%d\n", err); net/dccp/ackvec.c: In function 'dccp_ackvec_update_old': ../net/dccp/ackvec.c:163:80: warning: suggest braces around empty body in an 'else' statement [-Wempty-body] 163 | (unsigned long long)seqno, state); Fixes: dc841e30eaea ("dccp: Extend CCID packet dequeueing interface") Fixes: 380240864451 ("dccp ccid-2: Update code for the Ack Vector input/registration routine") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: dccp@vger.kernel.org Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 86aab09a4870bb8346c9579864588c3d7f555299 ]

GCC complains about empty macros in an 'if' statement, so convert
them to 'do {} while (0)' macros.

Fixes these build warnings:

net/dccp/output.c: In function 'dccp_xmit_packet':
../net/dccp/output.c:283:71: warning: suggest braces around empty body in an 'if' statement [-Wempty-body]
  283 |                 dccp_pr_debug("transmit_skb() returned err=%d\n", err);
net/dccp/ackvec.c: In function 'dccp_ackvec_update_old':
../net/dccp/ackvec.c:163:80: warning: suggest braces around empty body in an 'else' statement [-Wempty-body]
  163 |                                               (unsigned long long)seqno, state);

Fixes: dc841e30eaea ("dccp: Extend CCID packet dequeueing interface")
Fixes: 380240864451 ("dccp ccid-2: Update code for the Ack Vector input/registration routine")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: dccp@vger.kernel.org
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ipv6: weaken the v4mapped source check 2021-04-07T10:05:38+00:00 Jakub Kicinski kuba@kernel.org 2021-03-17T16:55:15+00:00 1c503dd09af14ba9885bc1bf2a2cc0371f1f0ae1 [ Upstream commit dcc32f4f183ab8479041b23a1525d48233df1d43 ] This reverts commit 6af1799aaf3f1bc8defedddfa00df3192445bbf3. Commit 6af1799aaf3f ("ipv6: drop incoming packets having a v4mapped source address") introduced an input check against v4mapped addresses. Use of such addresses on the wire is indeed questionable and not allowed on public Internet. As the commit pointed out https://tools.ietf.org/html/draft-itojun-v6ops-v4mapped-harmful-02 lists potential issues. Unfortunately there are applications which use v4mapped addresses, and breaking them is a clear regression. For example v4mapped addresses (or any semi-valid addresses, really) may be used for uni-direction event streams or packet export. Since the issue which sparked the addition of the check was with TCP and request_socks in particular push the check down to TCPv6 and DCCP. This restores the ability to receive UDPv6 packets with v4mapped address as the source. Keep using the IPSTATS_MIB_INHDRERRORS statistic to minimize the user-visible changes. Fixes: 6af1799aaf3f ("ipv6: drop incoming packets having a v4mapped source address") Reported-by: Sunyi Shao <sunyishao@fb.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit dcc32f4f183ab8479041b23a1525d48233df1d43 ]

This reverts commit 6af1799aaf3f1bc8defedddfa00df3192445bbf3.

Commit 6af1799aaf3f ("ipv6: drop incoming packets having a v4mapped
source address") introduced an input check against v4mapped addresses.
Use of such addresses on the wire is indeed questionable and not
allowed on public Internet. As the commit pointed out

  https://tools.ietf.org/html/draft-itojun-v6ops-v4mapped-harmful-02

lists potential issues.

Unfortunately there are applications which use v4mapped addresses,
and breaking them is a clear regression. For example v4mapped
addresses (or any semi-valid addresses, really) may be used
for uni-direction event streams or packet export.

Since the issue which sparked the addition of the check was with
TCP and request_socks in particular push the check down to TCPv6
and DCCP. This restores the ability to receive UDPv6 packets with
v4mapped address as the source.

Keep using the IPSTATS_MIB_INHDRERRORS statistic to minimize the
user-visible changes.

Fixes: 6af1799aaf3f ("ipv6: drop incoming packets having a v4mapped source address")
Reported-by: Sunyi Shao <sunyishao@fb.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
net: ipv6: add net argument to ip6_dst_lookup_flow 2020-05-20T06:15:30+00:00 Sabrina Dubroca sd@queasysnail.net 2019-12-04T14:35:52+00:00 5cc5fa7a8778da20941e7f78edc87090e34cb515 commit c4e85f73afb6384123e5ef1bba3315b2e3ad031e upstream. This will be used in the conversion of ipv6_stub to ip6_dst_lookup_flow, as some modules currently pass a net argument without a socket to ip6_dst_lookup. This is equivalent to commit 343d60aada5a ("ipv6: change ipv6_stub_impl.ipv6_dst_lookup to take net argument"). Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 4.9: adjust context] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Sasha Levin <sashal@kernel.org> 
commit c4e85f73afb6384123e5ef1bba3315b2e3ad031e upstream.

This will be used in the conversion of ipv6_stub to ip6_dst_lookup_flow,
as some modules currently pass a net argument without a socket to
ip6_dst_lookup. This is equivalent to commit 343d60aada5a ("ipv6: change
ipv6_stub_impl.ipv6_dst_lookup to take net argument").

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
dccp: Fix memleak in __feat_register_sp 2020-01-23T07:19:34+00:00 YueHaibing yuehaibing@huawei.com 2019-04-01T01:35:54+00:00 33cab7a0a84d35908c75c4b46c88769be7902556 commit 1d3ff0950e2b40dc861b1739029649d03f591820 upstream. If dccp_feat_push_change fails, we forget free the mem which is alloced by kmemdup in dccp_feat_clone_sp_val. Reported-by: Hulk Robot <hulkci@huawei.com> Fixes: e8ef967a54f4 ("dccp: Registration routines for changing feature values") Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 1d3ff0950e2b40dc861b1739029649d03f591820 upstream.

If dccp_feat_push_change fails, we forget free the mem
which is alloced by kmemdup in dccp_feat_clone_sp_val.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: e8ef967a54f4 ("dccp: Registration routines for changing feature values")
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
inet: stop leaking jiffies on the wire 2019-11-10T10:23:29+00:00 Eric Dumazet edumazet@google.com 2019-11-01T17:32:19+00:00 a67a32da603cba284c0ed96878e19acf00263373 [ Upstream commit a904a0693c189691eeee64f6c6b188bd7dc244e9 ] Historically linux tried to stick to RFC 791, 1122, 2003 for IPv4 ID field generation. RFC 6864 made clear that no matter how hard we try, we can not ensure unicity of IP ID within maximum lifetime for all datagrams with a given source address/destination address/protocol tuple. Linux uses a per socket inet generator (inet_id), initialized at connection startup with a XOR of 'jiffies' and other fields that appear clear on the wire. Thiemo Nagel pointed that this strategy is a privacy concern as this provides 16 bits of entropy to fingerprint devices. Let's switch to a random starting point, this is just as good as far as RFC 6864 is concerned and does not leak anything critical. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Thiemo Nagel <tnagel@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit a904a0693c189691eeee64f6c6b188bd7dc244e9 ]

Historically linux tried to stick to RFC 791, 1122, 2003
for IPv4 ID field generation.

RFC 6864 made clear that no matter how hard we try,
we can not ensure unicity of IP ID within maximum
lifetime for all datagrams with a given source
address/destination address/protocol tuple.

Linux uses a per socket inet generator (inet_id), initialized
at connection startup with a XOR of 'jiffies' and other
fields that appear clear on the wire.

Thiemo Nagel pointed that this strategy is a privacy
concern as this provides 16 bits of entropy to fingerprint
devices.

Let's switch to a random starting point, this is just as
good as far as RFC 6864 is concerned and does not leak
anything critical.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Thiemo Nagel <tnagel@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dccp: do not leak jiffies on the wire 2019-11-10T10:23:22+00:00 Eric Dumazet edumazet@google.com 2019-11-04T15:57:55+00:00 afd9a802e235b31ddd491fe1efba3df0d410d127 [ Upstream commit 3d1e5039f5f87a8731202ceca08764ee7cb010d3 ] For some reason I missed the case of DCCP passive flows in my previous patch. Fixes: a904a0693c18 ("inet: stop leaking jiffies on the wire") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Thiemo Nagel <tnagel@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 3d1e5039f5f87a8731202ceca08764ee7cb010d3 ]

For some reason I missed the case of DCCP passive
flows in my previous patch.

Fixes: a904a0693c18 ("inet: stop leaking jiffies on the wire")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Thiemo Nagel <tnagel@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dccp: do not use ipv6 header for ipv4 flow 2019-04-03T04:24:14+00:00 Eric Dumazet edumazet@google.com 2019-03-19T12:46:18+00:00 dc8390f9de1455cb96287c6c3cc4e133f103c58c [ Upstream commit e0aa67709f89d08c8d8e5bdd9e0b649df61d0090 ] When a dual stack dccp listener accepts an ipv4 flow, it should not attempt to use an ipv6 header or inet6_iif() helper. Fixes: 3df80d9320bc ("[DCCP]: Introduce DCCPv6") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit e0aa67709f89d08c8d8e5bdd9e0b649df61d0090 ]

When a dual stack dccp listener accepts an ipv4 flow,
it should not attempt to use an ipv6 header or
inet6_iif() helper.

Fixes: 3df80d9320bc ("[DCCP]: Introduce DCCPv6")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tcp/dccp: drop SYN packets if accept queue is full 2019-03-27T05:13:04+00:00 Eric Dumazet edumazet@google.com 2016-10-26T16:27:57+00:00 dfe4f69f8ee06f8a95877cf8fb98795e8ac65eca commit 5ea8ea2cb7f1d0db15762c9b0bb9e7330425a071 upstream. Per listen(fd, backlog) rules, there is really no point accepting a SYN, sending a SYNACK, and dropping the following ACK packet if accept queue is full, because application is not draining accept queue fast enough. This behavior is fooling TCP clients that believe they established a flow, while there is nothing at server side. They might then send about 10 MSS (if using IW10) that will be dropped anyway while server is under stress. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 5ea8ea2cb7f1d0db15762c9b0bb9e7330425a071 upstream.

Per listen(fd, backlog) rules, there is really no point accepting a SYN,
sending a SYNACK, and dropping the following ACK packet if accept queue
is full, because application is not draining accept queue fast enough.

This behavior is fooling TCP clients that believe they established a
flow, while there is nothing at server side. They might then send about
10 MSS (if using IW10) that will be dropped anyway while server is under
stress.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dccp: fool proof ccid_hc_[rt]x_parse_options() 2019-02-12T18:44:59+00:00 Eric Dumazet edumazet@google.com 2019-01-30T19:39:41+00:00 2dd6c1155d5c018b98686571e4a45b41d501dfca [ Upstream commit 9b1f19d810e92d6cdc68455fbc22d9f961a58ce1 ] Similarly to commit 276bdb82dedb ("dccp: check ccid before dereferencing") it is wise to test for a NULL ccid. kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.0.0-rc3+ #37 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:ccid_hc_tx_parse_options net/dccp/ccid.h:205 [inline] RIP: 0010:dccp_parse_options+0x8d9/0x12b0 net/dccp/options.c:233 Code: c5 0f b6 75 b3 80 38 00 0f 85 d6 08 00 00 48 b9 00 00 00 00 00 fc ff df 48 8b 45 b8 4c 8b b8 f8 07 00 00 4c 89 f8 48 c1 e8 03 <80> 3c 08 00 0f 85 95 08 00 00 48 b8 00 00 00 00 00 fc ff df 4d 8b kobject: 'loop5' (0000000080f78fc1): kobject_uevent_env RSP: 0018:ffff8880a94df0b8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff8880858ac723 RCX: dffffc0000000000 RDX: 0000000000000100 RSI: 0000000000000007 RDI: 0000000000000001 RBP: ffff8880a94df140 R08: 0000000000000001 R09: ffff888061b83a80 R10: ffffed100c370752 R11: ffff888061b83a97 R12: 0000000000000026 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0defa33518 CR3: 000000008db5e000 CR4: 00000000001406e0 kobject: 'loop5' (0000000080f78fc1): fill_kobj_path: path = '/devices/virtual/block/loop5' DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: dccp_rcv_state_process+0x2b6/0x1af6 net/dccp/input.c:654 dccp_v4_do_rcv+0x100/0x190 net/dccp/ipv4.c:688 sk_backlog_rcv include/net/sock.h:936 [inline] __sk_receive_skb+0x3a9/0xea0 net/core/sock.c:473 dccp_v4_rcv+0x10cb/0x1f80 net/dccp/ipv4.c:880 ip_protocol_deliver_rcu+0xb6/0xa20 net/ipv4/ip_input.c:208 ip_local_deliver_finish+0x23b/0x390 net/ipv4/ip_input.c:234 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ip_local_deliver+0x1f0/0x740 net/ipv4/ip_input.c:255 dst_input include/net/dst.h:450 [inline] ip_rcv_finish+0x1f4/0x2f0 net/ipv4/ip_input.c:414 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ip_rcv+0xed/0x620 net/ipv4/ip_input.c:524 __netif_receive_skb_one_core+0x160/0x210 net/core/dev.c:4973 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083 process_backlog+0x206/0x750 net/core/dev.c:5923 napi_poll net/core/dev.c:6346 [inline] net_rx_action+0x76d/0x1930 net/core/dev.c:6412 __do_softirq+0x30b/0xb11 kernel/softirq.c:292 run_ksoftirqd kernel/softirq.c:654 [inline] run_ksoftirqd+0x8e/0x110 kernel/softirq.c:646 smpboot_thread_fn+0x6ab/0xa10 kernel/smpboot.c:164 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Modules linked in: ---[ end trace 58a0ba03bea2c376 ]--- RIP: 0010:ccid_hc_tx_parse_options net/dccp/ccid.h:205 [inline] RIP: 0010:dccp_parse_options+0x8d9/0x12b0 net/dccp/options.c:233 Code: c5 0f b6 75 b3 80 38 00 0f 85 d6 08 00 00 48 b9 00 00 00 00 00 fc ff df 48 8b 45 b8 4c 8b b8 f8 07 00 00 4c 89 f8 48 c1 e8 03 <80> 3c 08 00 0f 85 95 08 00 00 48 b8 00 00 00 00 00 fc ff df 4d 8b RSP: 0018:ffff8880a94df0b8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff8880858ac723 RCX: dffffc0000000000 RDX: 0000000000000100 RSI: 0000000000000007 RDI: 0000000000000001 RBP: ffff8880a94df140 R08: 0000000000000001 R09: ffff888061b83a80 R10: ffffed100c370752 R11: ffff888061b83a97 R12: 0000000000000026 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0defa33518 CR3: 0000000009871000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 9b1f19d810e92d6cdc68455fbc22d9f961a58ce1 ]

Similarly to commit 276bdb82dedb ("dccp: check ccid before dereferencing")
it is wise to test for a NULL ccid.

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.0.0-rc3+ #37
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:ccid_hc_tx_parse_options net/dccp/ccid.h:205 [inline]
RIP: 0010:dccp_parse_options+0x8d9/0x12b0 net/dccp/options.c:233
Code: c5 0f b6 75 b3 80 38 00 0f 85 d6 08 00 00 48 b9 00 00 00 00 00 fc ff df 48 8b 45 b8 4c 8b b8 f8 07 00 00 4c 89 f8 48 c1 e8 03 <80> 3c 08 00 0f 85 95 08 00 00 48 b8 00 00 00 00 00 fc ff df 4d 8b
kobject: 'loop5' (0000000080f78fc1): kobject_uevent_env
RSP: 0018:ffff8880a94df0b8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8880858ac723 RCX: dffffc0000000000
RDX: 0000000000000100 RSI: 0000000000000007 RDI: 0000000000000001
RBP: ffff8880a94df140 R08: 0000000000000001 R09: ffff888061b83a80
R10: ffffed100c370752 R11: ffff888061b83a97 R12: 0000000000000026
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0defa33518 CR3: 000000008db5e000 CR4: 00000000001406e0
kobject: 'loop5' (0000000080f78fc1): fill_kobj_path: path = '/devices/virtual/block/loop5'
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 dccp_rcv_state_process+0x2b6/0x1af6 net/dccp/input.c:654
 dccp_v4_do_rcv+0x100/0x190 net/dccp/ipv4.c:688
 sk_backlog_rcv include/net/sock.h:936 [inline]
 __sk_receive_skb+0x3a9/0xea0 net/core/sock.c:473
 dccp_v4_rcv+0x10cb/0x1f80 net/dccp/ipv4.c:880
 ip_protocol_deliver_rcu+0xb6/0xa20 net/ipv4/ip_input.c:208
 ip_local_deliver_finish+0x23b/0x390 net/ipv4/ip_input.c:234
 NF_HOOK include/linux/netfilter.h:289 [inline]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 ip_local_deliver+0x1f0/0x740 net/ipv4/ip_input.c:255
 dst_input include/net/dst.h:450 [inline]
 ip_rcv_finish+0x1f4/0x2f0 net/ipv4/ip_input.c:414
 NF_HOOK include/linux/netfilter.h:289 [inline]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 ip_rcv+0xed/0x620 net/ipv4/ip_input.c:524
 __netif_receive_skb_one_core+0x160/0x210 net/core/dev.c:4973
 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083
 process_backlog+0x206/0x750 net/core/dev.c:5923
 napi_poll net/core/dev.c:6346 [inline]
 net_rx_action+0x76d/0x1930 net/core/dev.c:6412
 __do_softirq+0x30b/0xb11 kernel/softirq.c:292
 run_ksoftirqd kernel/softirq.c:654 [inline]
 run_ksoftirqd+0x8e/0x110 kernel/softirq.c:646
 smpboot_thread_fn+0x6ab/0xa10 kernel/smpboot.c:164
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Modules linked in:
---[ end trace 58a0ba03bea2c376 ]---
RIP: 0010:ccid_hc_tx_parse_options net/dccp/ccid.h:205 [inline]
RIP: 0010:dccp_parse_options+0x8d9/0x12b0 net/dccp/options.c:233
Code: c5 0f b6 75 b3 80 38 00 0f 85 d6 08 00 00 48 b9 00 00 00 00 00 fc ff df 48 8b 45 b8 4c 8b b8 f8 07 00 00 4c 89 f8 48 c1 e8 03 <80> 3c 08 00 0f 85 95 08 00 00 48 b8 00 00 00 00 00 fc ff df 4d 8b
RSP: 0018:ffff8880a94df0b8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8880858ac723 RCX: dffffc0000000000
RDX: 0000000000000100 RSI: 0000000000000007 RDI: 0000000000000001
RBP: ffff8880a94df140 R08: 0000000000000001 R09: ffff888061b83a80
R10: ffffed100c370752 R11: ffff888061b83a97 R12: 0000000000000026
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0defa33518 CR3: 0000000009871000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>