Commit Graph

352 Commits

Author SHA1 Message Date
Cong Wang
af49338895 net: Implement ->sock_is_readable() for UDP and AF_UNIX
Yucong noticed we can't poll() sockets in sockmap even
when they are the destination sockets of redirections.
This is because we never poll any psock queues in ->poll(),
except for TCP. With ->sock_is_readable() now we can
overwrite >sock_is_readable(), invoke and implement it for
both UDP and AF_UNIX sockets.

Reported-by: Yucong Sun <sunyucong@gmail.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211008203306.37525-4-xiyou.wangcong@gmail.com
2021-10-26 12:29:33 -07:00
Stephen Boyd
0edf0824e0 af_unix: Rename UNIX-DGRAM to UNIX to maintain backwards compatability
Then name of this protocol changed in commit 94531cfcbe ("af_unix: Add
unix_stream_proto for sockmap") because that commit added stream support
to the af_unix protocol. Renaming the existing protocol makes a ChromeOS
protocol test[1] fail now that the name has changed in
/proc/net/protocols from "UNIX" to "UNIX-DGRAM".

Let's put the name back to how it was while keeping the stream protocol
as "UNIX-STREAM" so that the procfs interface doesn't change. This fixes
the test and maintains backwards compatibility in proc.

Cc: Jiang Wang <jiang.wang@bytedance.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Cong Wang <cong.wang@bytedance.com>
Cc: Jakub Sitnicki <jakub@cloudflare.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Dmitry Osipenko <digetx@gmail.com>
Link: https://source.chromium.org/chromiumos/chromiumos/codesearch/+/main:src/platform/tast-tests/src/chromiumos/tast/local/bundles/cros/network/supported_protocols.go;l=50;drc=e8b1c3f94cb40a054f4aa1ef1aff61e75dc38f18 [1]
Fixes: 94531cfcbe ("af_unix: Add unix_stream_proto for sockmap")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-12 11:16:49 +01:00
Jakub Kicinski
7671b026bb Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2021-10-07

We've added 7 non-merge commits during the last 8 day(s) which contain
a total of 8 files changed, 38 insertions(+), 21 deletions(-).

The main changes are:

1) Fix ARM BPF JIT to preserve caller-saved regs for DIV/MOD JIT-internal
   helper call, from Johan Almbladh.

2) Fix integer overflow in BPF stack map element size calculation when
   used with preallocation, from Tatsuhiko Yasumatsu.

3) Fix an AF_UNIX regression due to added BPF sockmap support related
   to shutdown handling, from Jiang Wang.

4) Fix a segfault in libbpf when generating light skeletons from objects
   without BTF, from Kumar Kartikeya Dwivedi.

5) Fix a libbpf memory leak in strset to free the actual struct strset
   itself, from Andrii Nakryiko.

6) Dual-license bpf_insn.h similarly as we did for libbpf and bpftool,
   with ACKs from all contributors, from Luca Boccassi.
====================

Link: https://lore.kernel.org/r/20211007135010.21143-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-07 07:11:33 -07:00
Jiang Wang
d0c6416bd7 unix: Fix an issue in unix_shutdown causing the other end read/write failures
Commit 94531cfcbe ("af_unix: Add unix_stream_proto for sockmap") sets
unix domain socket peer state to TCP_CLOSE in unix_shutdown. This could
happen when the local end is shutdown but the other end is not. Then,
the other end will get read or write failures which is not expected.
Fix the issue by setting the local state to shutdown.

Fixes: 94531cfcbe ("af_unix: Add unix_stream_proto for sockmap")
Reported-by: Casey Schaufler <casey@schaufler-ca.com>
Suggested-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Jiang Wang <jiang.wang@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20211004232530.2377085-1-jiang.wang@bytedance.com
2021-10-06 14:40:21 +02:00
Eric Dumazet
35306eb238 af_unix: fix races in sk_peer_pid and sk_peer_cred accesses
Jann Horn reported that SO_PEERCRED and SO_PEERGROUPS implementations
are racy, as af_unix can concurrently change sk_peer_pid and sk_peer_cred.

In order to fix this issue, this patch adds a new spinlock that needs
to be used whenever these fields are read or written.

Jann also pointed out that l2cap_sock_get_peer_pid_cb() is currently
reading sk->sk_peer_pid which makes no sense, as this field
is only possibly set by AF_UNIX sockets.
We will have to clean this in a separate patch.
This could be done by reverting b48596d1dc "Bluetooth: L2CAP: Add get_peer_pid callback"
or implementing what was truly expected.

Fixes: 109f6e39fa ("af_unix: Allow SO_PEERCRED to work across namespaces.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jann Horn <jannh@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30 14:18:40 +01:00
Kuniyuki Iwashima
f4bd73b5a9 af_unix: Return errno instead of NULL in unix_create1().
unix_create1() returns NULL on error, and the callers assume that it never
fails for reasons other than out of memory.  So, the callers always return
-ENOMEM when unix_create1() fails.

However, it also returns NULL when the number of af_unix sockets exceeds
twice the limit controlled by sysctl: fs.file-max.  In this case, the
callers should return -ENFILE like alloc_empty_file().

This patch changes unix_create1() to return the correct error value instead
of NULL on error.

Out of curiosity, the assumption has been wrong since 1999 due to this
change introduced in 2.2.4 [0].

  diff -u --recursive --new-file v2.2.3/linux/net/unix/af_unix.c linux/net/unix/af_unix.c
  --- v2.2.3/linux/net/unix/af_unix.c	Tue Jan 19 11:32:53 1999
  +++ linux/net/unix/af_unix.c	Sun Mar 21 07:22:00 1999
  @@ -388,6 +413,9 @@
   {
   	struct sock *sk;

  +	if (atomic_read(&unix_nr_socks) >= 2*max_files)
  +		return NULL;
  +
   	MOD_INC_USE_COUNT;
   	sk = sk_alloc(PF_UNIX, GFP_KERNEL, 1);
   	if (!sk) {

[0]: https://cdn.kernel.org/pub/linux/kernel/v2.2/patch-2.2.4.gz

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-28 13:22:57 +01:00
Eric Dumazet
04f08eb44b net/af_unix: fix a data-race in unix_dgram_poll
syzbot reported another data-race in af_unix [1]

Lets change __skb_insert() to use WRITE_ONCE() when changing
skb head qlen.

Also, change unix_dgram_poll() to use lockless version
of unix_recvq_full()

It is verry possible we can switch all/most unix_recvq_full()
to the lockless version, this will be done in a future kernel version.

[1] HEAD commit: 8596e589b7

BUG: KCSAN: data-race in skb_queue_tail / unix_dgram_poll

write to 0xffff88814eeb24e0 of 4 bytes by task 25815 on cpu 0:
 __skb_insert include/linux/skbuff.h:1938 [inline]
 __skb_queue_before include/linux/skbuff.h:2043 [inline]
 __skb_queue_tail include/linux/skbuff.h:2076 [inline]
 skb_queue_tail+0x80/0xa0 net/core/skbuff.c:3264
 unix_dgram_sendmsg+0xff2/0x1600 net/unix/af_unix.c:1850
 sock_sendmsg_nosec net/socket.c:703 [inline]
 sock_sendmsg net/socket.c:723 [inline]
 ____sys_sendmsg+0x360/0x4d0 net/socket.c:2392
 ___sys_sendmsg net/socket.c:2446 [inline]
 __sys_sendmmsg+0x315/0x4b0 net/socket.c:2532
 __do_sys_sendmmsg net/socket.c:2561 [inline]
 __se_sys_sendmmsg net/socket.c:2558 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2558
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88814eeb24e0 of 4 bytes by task 25834 on cpu 1:
 skb_queue_len include/linux/skbuff.h:1869 [inline]
 unix_recvq_full net/unix/af_unix.c:194 [inline]
 unix_dgram_poll+0x2bc/0x3e0 net/unix/af_unix.c:2777
 sock_poll+0x23e/0x260 net/socket.c:1288
 vfs_poll include/linux/poll.h:90 [inline]
 ep_item_poll fs/eventpoll.c:846 [inline]
 ep_send_events fs/eventpoll.c:1683 [inline]
 ep_poll fs/eventpoll.c:1798 [inline]
 do_epoll_wait+0x6ad/0xf00 fs/eventpoll.c:2226
 __do_sys_epoll_wait fs/eventpoll.c:2238 [inline]
 __se_sys_epoll_wait fs/eventpoll.c:2233 [inline]
 __x64_sys_epoll_wait+0xf6/0x120 fs/eventpoll.c:2233
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000001b -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 25834 Comm: syz-executor.1 Tainted: G        W         5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: 86b18aaa2b ("skbuff: fix a data race in skb_queue_len()")
Cc: Qian Cai <cai@lca.pw>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-09 10:57:52 +01:00
Eric Dumazet
dc56ad7028 af_unix: fix potential NULL deref in unix_dgram_connect()
syzbot was able to trigger NULL deref in unix_dgram_connect() [1]

This happens in

	if (unix_peer(sk))
		sk->sk_state = other->sk_state = TCP_ESTABLISHED; // crash because @other is NULL

Because locks have been dropped, unix_peer() might be non NULL,
while @other is NULL (AF_UNSPEC case)

We need to move code around, so that we no longer access
unix_peer() and sk_state while locks have been released.

[1]
general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
CPU: 0 PID: 10341 Comm: syz-executor239 Not tainted 5.14.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:unix_dgram_connect+0x32a/0xc60 net/unix/af_unix.c:1226
Code: 00 00 45 31 ed 49 83 bc 24 f8 05 00 00 00 74 69 e8 eb 5b a6 f9 48 8d 7d 12 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 e0 07 00 00
RSP: 0018:ffffc9000a89fcd8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000004 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff87cf4ef5 RDI: 0000000000000012
RBP: 0000000000000000 R08: 0000000000000000 R09: ffff88802e1917c3
R10: ffffffff87cf4eba R11: 0000000000000001 R12: ffff88802e191740
R13: 0000000000000000 R14: ffff88802e191d38 R15: ffff88802e1917c0
FS:  00007f3eb0052700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004787d0 CR3: 0000000029c0a000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __sys_connect_file+0x155/0x1a0 net/socket.c:1890
 __sys_connect+0x161/0x190 net/socket.c:1907
 __do_sys_connect net/socket.c:1917 [inline]
 __se_sys_connect net/socket.c:1914 [inline]
 __x64_sys_connect+0x6f/0xb0 net/socket.c:1914
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x446a89
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 a1 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3eb0052208 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 00000000004cc4d8 RCX: 0000000000446a89
RDX: 000000000000006e RSI: 0000000020000180 RDI: 0000000000000003
RBP: 00000000004cc4d0 R08: 00007f3eb0052700 R09: 0000000000000000
R10: 00007f3eb0052700 R11: 0000000000000246 R12: 00000000004cc4dc
R13: 00007ffd791e79cf R14: 00007f3eb0052300 R15: 0000000000022000
Modules linked in:
---[ end trace 4eb809357514968c ]---
RIP: 0010:unix_dgram_connect+0x32a/0xc60 net/unix/af_unix.c:1226
Code: 00 00 45 31 ed 49 83 bc 24 f8 05 00 00 00 74 69 e8 eb 5b a6 f9 48 8d 7d 12 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 48 89 fa 83 e2 07 38 d0 7f 08 84 c0 0f 85 e0 07 00 00
RSP: 0018:ffffc9000a89fcd8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000004 RCX: 0000000000000000
RDX: 0000000000000002 RSI: ffffffff87cf4ef5 RDI: 0000000000000012
RBP: 0000000000000000 R08: 0000000000000000 R09: ffff88802e1917c3
R10: ffffffff87cf4eba R11: 0000000000000001 R12: ffff88802e191740
R13: 0000000000000000 R14: ffff88802e191d38 R15: ffff88802e1917c0
FS:  00007f3eb0052700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd791fe960 CR3: 0000000029c0a000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Fixes: 83301b5367 ("af_unix: Set TCP_ESTABLISHED for datagram sockets too")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Cong Wang <cong.wang@bytedance.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-31 11:31:52 +01:00
Jakub Kicinski
19a31d7921 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
bpf-next 2021-08-31

We've added 116 non-merge commits during the last 17 day(s) which contain
a total of 126 files changed, 6813 insertions(+), 4027 deletions(-).

The main changes are:

1) Add opaque bpf_cookie to perf link which the program can read out again,
   to be used in libbpf-based USDT library, from Andrii Nakryiko.

2) Add bpf_task_pt_regs() helper to access userspace pt_regs, from Daniel Xu.

3) Add support for UNIX stream type sockets for BPF sockmap, from Jiang Wang.

4) Allow BPF TCP congestion control progs to call bpf_setsockopt() e.g. to switch
   to another congestion control algorithm during init, from Martin KaFai Lau.

5) Extend BPF iterator support for UNIX domain sockets, from Kuniyuki Iwashima.

6) Allow bpf_{set,get}sockopt() calls from setsockopt progs, from Prankur Gupta.

7) Add bpf_get_netns_cookie() helper for BPF_PROG_TYPE_{SOCK_OPS,CGROUP_SOCKOPT}
   progs, from Xu Liu and Stanislav Fomichev.

8) Support for __weak typed ksyms in libbpf, from Hao Luo.

9) Shrink struct cgroup_bpf by 504 bytes through refactoring, from Dave Marchevsky.

10) Fix a smatch complaint in verifier's narrow load handling, from Andrey Ignatov.

11) Fix BPF interpreter's tail call count limit, from Daniel Borkmann.

12) Big batch of improvements to BPF selftests, from Magnus Karlsson, Li Zhijian,
    Yucong Sun, Yonghong Song, Ilya Leoshkevich, Jussi Maki, Ilya Leoshkevich, others.

13) Another big batch to revamp XDP samples in order to give them consistent look
    and feel, from Kumar Kartikeya Dwivedi.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (116 commits)
  MAINTAINERS: Remove self from powerpc BPF JIT
  selftests/bpf: Fix potential unreleased lock
  samples: bpf: Fix uninitialized variable in xdp_redirect_cpu
  selftests/bpf: Reduce more flakyness in sockmap_listen
  bpf: Fix bpf-next builds without CONFIG_BPF_EVENTS
  bpf: selftests: Add dctcp fallback test
  bpf: selftests: Add connect_to_fd_opts to network_helpers
  bpf: selftests: Add sk_state to bpf_tcp_helpers.h
  bpf: tcp: Allow bpf-tcp-cc to call bpf_(get|set)sockopt
  selftests: xsk: Preface options with opt
  selftests: xsk: Make enums lower case
  selftests: xsk: Generate packets from specification
  selftests: xsk: Generate packet directly in umem
  selftests: xsk: Simplify cleanup of ifobjects
  selftests: xsk: Decrease sending speed
  selftests: xsk: Validate tx stats on tx thread
  selftests: xsk: Simplify packet validation in xsk tests
  selftests: xsk: Rename worker_* functions that are not thread entry points
  selftests: xsk: Disassociate umem size with packets sent
  selftests: xsk: Remove end-of-test packet
  ...
====================

Link: https://lore.kernel.org/r/20210830225618.11634-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-30 16:42:47 -07:00
Jiang Wang
d359902d5c af_unix: Fix NULL pointer bug in unix_shutdown
Commit 94531cfcbe ("af_unix: Add unix_stream_proto for sockmap")
introduced a bug for af_unix SEQPACKET type. In unix_shutdown, the
unhash function will call prot->unhash(), which is NULL for SEQPACKET.
And kernel will panic. On ARM32, it will show following messages: (it
likely affects x86 too).

Fix the bug by checking the prot->unhash is NULL or not first.

Kernel log:
<--- cut here ---
 Unable to handle kernel NULL pointer dereference at virtual address
00000000
 pgd = 2fba1ffb
 *pgd=00000000
 Internal error: Oops: 80000005 [#1] PREEMPT SMP THUMB2
 Modules linked in:
 CPU: 1 PID: 1999 Comm: falkon Tainted: G        W
5.14.0-rc5-01175-g94531cfcbe79-dirty #9240
 Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
 PC is at 0x0
 LR is at unix_shutdown+0x81/0x1a8
 pc : [<00000000>]    lr : [<c08f3311>]    psr: 600f0013
 sp : e45aff70  ip : e463a3c0  fp : beb54f04
 r10: 00000125  r9 : e45ae000  r8 : c4a56664
 r7 : 00000001  r6 : c4a56464  r5 : 00000001  r4 : c4a56400
 r3 : 00000000  r2 : c5a6b180  r1 : 00000000  r0 : c4a56400
 Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
 Control: 50c5387d  Table: 05aa804a  DAC: 00000051
 Register r0 information: slab PING start c4a56400 pointer offset 0
 Register r1 information: NULL pointer
 Register r2 information: slab task_struct start c5a6b180 pointer offset 0
 Register r3 information: NULL pointer
 Register r4 information: slab PING start c4a56400 pointer offset 0
 Register r5 information: non-paged memory
 Register r6 information: slab PING start c4a56400 pointer offset 100
 Register r7 information: non-paged memory
 Register r8 information: slab PING start c4a56400 pointer offset 612
 Register r9 information: non-slab/vmalloc memory
 Register r10 information: non-paged memory
 Register r11 information: non-paged memory
 Register r12 information: slab filp start e463a3c0 pointer offset 0
 Process falkon (pid: 1999, stack limit = 0x9ec48895)
 Stack: (0xe45aff70 to 0xe45b0000)
 ff60:                                     e45ae000 c5f26a00 00000000 00000125
 ff80: c0100264 c07f7fa3 beb54f04 fffffff7 00000001 e6f3fc0e b5e5e9ec beb54ec4
 ffa0: b5da0ccc c010024b b5e5e9ec beb54ec4 0000000f 00000000 00000000 beb54ebc
 ffc0: b5e5e9ec beb54ec4 b5da0ccc 00000125 beb54f58 00785238 beb5529c beb54f04
 ffe0: b5da1e24 beb54eac b301385c b62b6ee8 600f0030 0000000f 00000000 00000000
 [<c08f3311>] (unix_shutdown) from [<c07f7fa3>] (__sys_shutdown+0x2f/0x50)
 [<c07f7fa3>] (__sys_shutdown) from [<c010024b>]
(__sys_trace_return+0x1/0x16)
 Exception stack(0xe45affa8 to 0xe45afff0)

Fixes: 94531cfcbe ("af_unix: Add unix_stream_proto for sockmap")
Reported-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Jiang Wang <jiang.wang@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Link: https://lore.kernel.org/bpf/20210821180738.1151155-1-jiang.wang@bytedance.com
2021-08-23 14:56:01 +02:00
Jiang Wang
94531cfcbe af_unix: Add unix_stream_proto for sockmap
Previously, sockmap for AF_UNIX protocol only supports
dgram type. This patch add unix stream type support, which
is similar to unix_dgram_proto. To support sockmap, dgram
and stream cannot share the same unix_proto anymore, because
they have different implementations, such as unhash for stream
type (which will remove closed or disconnected sockets from the map),
so rename unix_proto to unix_dgram_proto and add a new
unix_stream_proto.

Also implement stream related sockmap functions.
And add dgram key words to those dgram specific functions.

Signed-off-by: Jiang Wang <jiang.wang@bytedance.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Cong Wang <cong.wang@bytedance.com>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210816190327.2739291-3-jiang.wang@bytedance.com
2021-08-16 18:43:39 -07:00
Jiang Wang
77462de14a af_unix: Add read_sock for stream socket types
To support sockmap for af_unix stream type, implement
read_sock, which is similar to the read_sock for unix
dgram sockets.

Signed-off-by: Jiang Wang <jiang.wang@bytedance.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Cong Wang <cong.wang@bytedance.com>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210816190327.2739291-2-jiang.wang@bytedance.com
2021-08-16 18:42:31 -07:00
Rao Shoaib
19eed72107 af_unix: check socket state when queuing OOB
edumazet@google.com pointed out that queue_oob
does not check socket state after acquiring
the lock. He also pointed to an incorrect usage
of kfree_skb and an unnecessary setting of skb
length. This patch addresses those issue.

Signed-off-by: Rao Shoaib <Rao.Shoaib@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-16 11:12:37 +01:00
Kuniyuki Iwashima
2c860a43dd bpf: af_unix: Implement BPF iterator for UNIX domain socket.
This patch implements the BPF iterator for the UNIX domain socket.

Currently, the batch optimisation introduced for the TCP iterator in the
commit 04c7820b77 ("bpf: tcp: Bpf iter batching and lock_sock") is not
used for the UNIX domain socket.  It will require replacing the big lock
for the hash table with small locks for each hash list not to block other
processes.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210814015718.42704-2-kuniyu@amazon.co.jp
2021-08-15 00:13:32 -07:00
Rao Shoaib
876c14ad01 af_unix: fix holding spinlock in oob handling
syzkaller found that OOB code was holding spinlock
while calling a function in which it could sleep.

Reported-by: syzbot+8760ca6c1ee783ac4abd@syzkaller.appspotmail.com
Fixes: 314001f0bf ("af_unix: Add OOB support")
Signed-off-by: Rao Shoaib <rao.shoaib@oracle.com>
Link: https://lore.kernel.org/r/20210811220652.567434-1-Rao.Shoaib@oracle.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-13 10:31:22 -07:00
Rao Shoaib
314001f0bf af_unix: Add OOB support
This patch adds OOB support for AF_UNIX sockets.
The semantics is same as TCP.

The last byte of a message with the OOB flag is
treated as the OOB byte. The byte is separated into
a skb and a pointer to the skb is stored in unix_sock.
The pointer is used to enforce OOB semantics.

Signed-off-by: Rao Shoaib <rao.shoaib@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04 09:55:52 +01:00
Jakub Kicinski
d2e11fd2b7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicting commits, all resolutions pretty trivial:

drivers/bus/mhi/pci_generic.c
  5c2c853159 ("bus: mhi: pci-generic: configurable network interface MRU")
  56f6f4c4eb ("bus: mhi: pci_generic: Apply no-op for wake using sideband wake boolean")

drivers/nfc/s3fwrn5/firmware.c
  a0302ff590 ("nfc: s3fwrn5: remove unnecessary label")
  46573e3ab0 ("nfc: s3fwrn5: fix undefined parameter values in dev_err()")
  801e541c79 ("nfc: s3fwrn5: fix undefined parameter values in dev_err()")

MAINTAINERS
  7d901a1e87 ("net: phy: add Maxlinear GPY115/21x/24x driver")
  8a7b46fa79 ("MAINTAINERS: add Yasushi SHOJI as reviewer for the Microchip CAN BUS Analyzer Tool driver")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-31 09:14:46 -07:00
Miklos Szeredi
cbcf01128d af_unix: fix garbage collect vs MSG_PEEK
unix_gc() assumes that candidate sockets can never gain an external
reference (i.e.  be installed into an fd) while the unix_gc_lock is
held.  Except for MSG_PEEK this is guaranteed by modifying inflight
count under the unix_gc_lock.

MSG_PEEK does not touch any variable protected by unix_gc_lock (file
count is not), yet it needs to be serialized with garbage collection.
Do this by locking/unlocking unix_gc_lock:

 1) increment file count

 2) lock/unlock barrier to make sure incremented file count is visible
    to garbage collection

 3) install file into fd

This is a lock barrier (unlike smp_mb()) that ensures that garbage
collection is run completely before or completely after the barrier.

Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-28 10:18:00 -07:00
Cong Wang
9825d866ce af_unix: Implement unix_dgram_bpf_recvmsg()
We have to implement unix_dgram_bpf_recvmsg() to replace the
original ->recvmsg() to retrieve skmsg from ingress_msg.

AF_UNIX is again special here because the lack of
sk_prot->recvmsg(). I simply add a special case inside
unix_dgram_recvmsg() to call sk->sk_prot->recvmsg() directly.

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210704190252.11866-8-xiyou.wangcong@gmail.com
2021-07-15 18:17:50 -07:00
Cong Wang
c63829182c af_unix: Implement ->psock_update_sk_prot()
Now we can implement unix_bpf_update_proto() to update
sk_prot, especially prot->close().

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210704190252.11866-7-xiyou.wangcong@gmail.com
2021-07-15 18:17:50 -07:00
Cong Wang
c7272e15f0 af_unix: Add a dummy ->close() for sockmap
Unlike af_inet, unix_proto is very different, it does not even
have a ->close(). We have to add a dummy implementation to
satisfy sockmap. Normally it is just a nop, it is introduced only
for sockmap to replace it.

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210704190252.11866-6-xiyou.wangcong@gmail.com
2021-07-15 18:17:50 -07:00
Cong Wang
83301b5367 af_unix: Set TCP_ESTABLISHED for datagram sockets too
Currently only unix stream socket sets TCP_ESTABLISHED,
datagram socket can set this too when they connect to its
peer socket. At least __ip4_datagram_connect() does the same.

This will be used to determine whether an AF_UNIX datagram
socket can be redirected to in sockmap.

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210704190252.11866-5-xiyou.wangcong@gmail.com
2021-07-15 18:17:50 -07:00
Cong Wang
29df44fa52 af_unix: Implement ->read_sock() for sockmap
Implement ->read_sock() for AF_UNIX datagram socket, it is
pretty much similar to udp_read_sock().

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210704190252.11866-4-xiyou.wangcong@gmail.com
2021-07-15 18:17:50 -07:00
Alexander Aring
e3ae2365ef net: sock: introduce sk_error_report
This patch introduces a function wrapper to call the sk_error_report
callback. That will prepare to add additional handling whenever
sk_error_report is called, for example to trace socket errors.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29 11:28:21 -07:00
Al Viro
be752283a2 __unix_find_socket_byname(): don't pass hash and type separately
We only care about exclusive or of those, so pass that directly.
Makes life simpler for callers as well...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 12:28:49 -07:00
Al Viro
c0c3b8d380 unix_bind_bsd(): unlink if we fail after successful mknod
We can do that more or less safely, since the parent is
held locked all along.  Yes, somebody might observe the
object via dcache, only to have it disappear afterwards,
but there's really no good way to prevent that.  It won't
race with other bind(2) or attempts to move the sucker
elsewhere, or put something else in its place - locked
parent prevents that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 12:28:49 -07:00
Al Viro
56c1731b28 unix_bind_bsd(): move done_path_create() call after dealing with ->bindlock
Final preparations for doing unlink on failure past the successful
mknod.  We can't hold ->bindlock over ->mknod() or ->unlink(), since
either might do sb_start_write() (e.g. on overlayfs).  However, we
can do it while holding filesystem and VFS locks - doing
	kern_path_create()
	vfs_mknod()
	grab ->bindlock
	if u->addr had been set
		drop ->bindlock
		done_path_create
		return -EINVAL
	else
		assign the address to socket
		drop ->bindlock
		done_path_create
		return 0
would be deadlock-free.  Here we massage unix_bind_bsd() to that
form.  We are still doing equivalent transformations.

Next commit will *not* be an equivalent transformation - it will
add a call of vfs_unlink() before done_path_create() in "alread bound"
case.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 12:28:49 -07:00
Al Viro
71e6be6f7d fold unix_mknod() into unix_bind_bsd()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 12:28:49 -07:00
Al Viro
fa42d910a3 unix_bind(): take BSD and abstract address cases into new helpers
unix_bind_bsd() and unix_bind_abstract() respectively.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 12:28:49 -07:00
Al Viro
aee5151705 unix_bind(): separate BSD and abstract cases
We do get some duplication that way, but it's minor compared to
parts that are different.  What we get is an ability to change
locking in BSD case without making failure exits very hard to
follow.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 12:28:49 -07:00
Al Viro
c34d458251 unix_bind(): allocate addr earlier
makes it easier to massage; we do pay for that by extra work
(kmalloc+memcpy+kfree) in some error cases, but those are not
on the hot paths anyway.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 12:28:49 -07:00
Al Viro
185ab886d3 af_unix: take address assignment/hash insertion into a new helper
Duplicated logics in all bind variants (autobind, bind-to-path,
bind-to-abstract) gets taken into a common helper.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-21 12:28:49 -07:00
Jakub Kicinski
adc2e56ebe Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Trivial conflicts in net/can/isotp.c and
tools/testing/selftests/net/mptcp/mptcp_connect.sh

scaled_ppm_to_ppb() was moved from drivers/ptp/ptp_clock.c
to include/linux/ptp_clock_kernel.h in -next so re-apply
the fix there.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-06-18 19:47:02 -07:00
Eric Dumazet
a494bd642d net/af_unix: fix a data-race in unix_dgram_sendmsg / unix_release_sock
While unix_may_send(sk, osk) is called while osk is locked, it appears
unix_release_sock() can overwrite unix_peer() after this lock has been
released, making KCSAN unhappy.

Changing unix_release_sock() to access/change unix_peer()
before lock is released should fix this issue.

BUG: KCSAN: data-race in unix_dgram_sendmsg / unix_release_sock

write to 0xffff88810465a338 of 8 bytes by task 20852 on cpu 1:
 unix_release_sock+0x4ed/0x6e0 net/unix/af_unix.c:558
 unix_release+0x2f/0x50 net/unix/af_unix.c:859
 __sock_release net/socket.c:599 [inline]
 sock_close+0x6c/0x150 net/socket.c:1258
 __fput+0x25b/0x4e0 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0xae/0x130 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x156/0x190 kernel/entry/common.c:209
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:302
 do_syscall_64+0x56/0x90 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88810465a338 of 8 bytes by task 20888 on cpu 0:
 unix_may_send net/unix/af_unix.c:189 [inline]
 unix_dgram_sendmsg+0x923/0x1610 net/unix/af_unix.c:1712
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 ____sys_sendmsg+0x360/0x4d0 net/socket.c:2350
 ___sys_sendmsg net/socket.c:2404 [inline]
 __sys_sendmmsg+0x315/0x4b0 net/socket.c:2490
 __do_sys_sendmmsg net/socket.c:2519 [inline]
 __se_sys_sendmmsg net/socket.c:2516 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2516
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0xffff888167905400 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 20888 Comm: syz-executor.0 Not tainted 5.13.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-16 12:51:55 -07:00
gushengxian
4e03d073af af_unix: remove the repeated word "and"
Remove the repeated word "and".

Signed-off-by: gushengxian <gushengxian@yulong.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-10 13:46:38 -07:00
Christian Brauner
7c02cf73d0
af_unix: handle idmapped mounts
When binding a non-abstract AF_UNIX socket it will gain a representation
in the filesystem. Enable the socket infrastructure to handle idmapped
mounts by passing down the user namespace of the mount the socket will
be created from. If the initial user namespace is passed nothing changes
so non-idmapped mounts will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-18-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:18 +01:00
Christian Brauner
6521f89170
namei: prepare for idmapped mounts
The various vfs_*() helpers are called by filesystems or by the vfs
itself to perform core operations such as create, link, mkdir, mknod, rename,
rmdir, tmpfile and unlink. Enable them to handle idmapped mounts. If the
inode is accessed through an idmapped mount map it into the
mount's user namespace and pass it down. Afterwards the checks and
operations are identical to non-idmapped mounts. If the initial user
namespace is passed nothing changes so non-idmapped mounts will see
identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-15-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:18 +01:00
Christian Brauner
02f92b3868
fs: add file and path permissions helpers
Add two simple helpers to check permissions on a file and path
respectively and convert over some callers. It simplifies quite a few
codepaths and also reduces the churn in later patches quite a bit.
Christoph also correctly points out that this makes codepaths (e.g.
ioctls) way easier to follow that would otherwise have to do more
complex argument passing than necessary.

Link: https://lore.kernel.org/r/20210121131959.646623-4-christian.brauner@ubuntu.com
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2021-01-24 14:27:16 +01:00
Or Cohen
c9bf52a173 net/af_unix: Remove unused old_pid variable
Commit 109f6e39fa ("af_unix: Allow SO_PEERCRED
to work across namespaces.") introduced the old_pid variable
in unix_listen, but it's never used.
Remove the declaration and the call to put_pid.

Signed-off-by: Or Cohen <orcohen@paloaltonetworks.com>
Link: https://lore.kernel.org/r/20201011153527.18628-1-orcohen@paloaltonetworks.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-13 17:21:46 -07:00
Jing Xiangfeng
c8c33b80f4 net: unix: remove redundant assignment to variable 'err'
After commit 37ab4fa784 ("net: unix: allow bind to fail on mutex lock"),
the assignment to err is redundant. So remove it.

Signed-off-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-21 14:51:37 -07:00
Gustavo A. R. Silva
df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Christoph Hellwig
a44d9e7210 net: make ->{get,set}sockopt in proto_ops optional
Just check for a NULL method instead of wiring up
sock_no_{get,set}sockopt.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-19 18:16:41 -07:00
Paolo Abeni
e427cad6ee net: datagram: drop 'destructor' argument from several helpers
The only users for such argument are the UDP protocol and the UNIX
socket family. We can safely reclaim the accounted memory directly
from the UDP code and, after the previous patch, we can do scm
stats accounting outside the datagram helpers.

Overall this cleans up a bit some datagram-related helpers, and
avoids an indirect call per packet in the UDP receive path.

v1 -> v2:
 - call scm_stat_del() only when not peeking - Kirill
 - fix build issue with CONFIG_INET_ESPINTCP

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-28 12:12:53 -08:00
Paolo Abeni
7782040b95 unix: uses an atomic type for scm files accounting
So the scm_stat_{add,del} helper can be invoked with no
additional lock held.

This clean-up the code a bit and will make the next
patch easier.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-28 12:12:53 -08:00
David S. Miller
9f6e055907 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
The mptcp conflict was overlapping additions.

The SMC conflict was an additional and removal happening at the same
time.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-27 18:31:39 -08:00
David S. Miller
5c05a164d4 unix: It's CONFIG_PROC_FS not CONFIG_PROCFS
Fixes: 3a12500ed5 ("unix: define and set show_fdinfo only if procfs is enabled")
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-27 11:52:35 -08:00
Tobias Klauser
3a12500ed5 unix: define and set show_fdinfo only if procfs is enabled
Follow the pattern used with other *_show_fdinfo functions and only
define unix_show_fdinfo and set it in proto_ops if CONFIG_PROCFS
is set.

Fixes: 3c32da19a8 ("unix: Show number of pending scm files of receive queue in fdinfo")
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-27 11:11:57 -08:00
Jules Irenge
48851e9e80 af_unix: Add missing annotation for unix_wait_for_peer()
Sparse reports a warning unix_wait_for_peer()

warning: context imbalance in unix_wait_for_peer() - unexpected unlock

The root cause is the missing annotation at unix_wait_for_peer()
Add the missing annotation __releases(&unix_sk(other)->lock)

Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-24 13:26:49 -08:00
Qian Cai
86b18aaa2b skbuff: fix a data race in skb_queue_len()
sk_buff.qlen can be accessed concurrently as noticed by KCSAN,

 BUG: KCSAN: data-race in __skb_try_recv_from_queue / unix_dgram_sendmsg

 read to 0xffff8a1b1d8a81c0 of 4 bytes by task 5371 on cpu 96:
  unix_dgram_sendmsg+0x9a9/0xb70 include/linux/skbuff.h:1821
				 net/unix/af_unix.c:1761
  ____sys_sendmsg+0x33e/0x370
  ___sys_sendmsg+0xa6/0xf0
  __sys_sendmsg+0x69/0xf0
  __x64_sys_sendmsg+0x51/0x70
  do_syscall_64+0x91/0xb47
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

 write to 0xffff8a1b1d8a81c0 of 4 bytes by task 1 on cpu 99:
  __skb_try_recv_from_queue+0x327/0x410 include/linux/skbuff.h:2029
  __skb_try_recv_datagram+0xbe/0x220
  unix_dgram_recvmsg+0xee/0x850
  ____sys_recvmsg+0x1fb/0x210
  ___sys_recvmsg+0xa2/0xf0
  __sys_recvmsg+0x66/0xf0
  __x64_sys_recvmsg+0x51/0x70
  do_syscall_64+0x91/0xb47
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Since only the read is operating as lockless, it could introduce a logic
bug in unix_recvq_full() due to the load tearing. Fix it by adding
a lockless variant of skb_queue_len() and unix_recvq_full() where
READ_ONCE() is on the read while WRITE_ONCE() is on the write similar to
the commit d7d16a8935 ("net: add skb_queue_empty_lockless()").

Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-06 13:59:10 +01:00
David S. Miller
4f2c17e0f3 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next
Steffen Klassert says:

====================
pull request (net-next): ipsec-next 2020-01-21

1) Add support for TCP encapsulation of IKE and ESP messages,
   as defined by RFC 8229. Patchset from Sabrina Dubroca.

Please note that there is a merge conflict in:

net/unix/af_unix.c

between commit:

3c32da19a8 ("unix: Show number of pending scm files of receive queue in fdinfo")

from the net-next tree and commit:

b50b0580d2 ("net: add queue argument to __skb_wait_for_more_packets and __skb_{,try_}recv_datagram")

from the ipsec-next tree.

The conflict can be solved as done in linux-next.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-21 12:18:20 +01:00