Commit Graph

28 Commits

Author SHA1 Message Date
Kuniyuki Iwashima
5aa57d9f2d af_unix: Don't return OOB skb in manage_oob().
syzbot reported use-after-free in unix_stream_recv_urg(). [0]

The scenario is

  1. send(MSG_OOB)
  2. recv(MSG_OOB)
     -> The consumed OOB remains in recv queue
  3. send(MSG_OOB)
  4. recv()
     -> manage_oob() returns the next skb of the consumed OOB
     -> This is also OOB, but unix_sk(sk)->oob_skb is not cleared
  5. recv(MSG_OOB)
     -> unix_sk(sk)->oob_skb is used but already freed

The recent commit 8594d9b85c ("af_unix: Don't call skb_get() for OOB
skb.") uncovered the issue.

If the OOB skb is consumed and the next skb is peeked in manage_oob(),
we still need to check if the skb is OOB.

Let's do so by falling back to the following checks in manage_oob()
and add the test case in selftest.

Note that we need to add a similar check for SIOCATMARK.

[0]:
BUG: KASAN: slab-use-after-free in unix_stream_read_actor+0xa6/0xb0 net/unix/af_unix.c:2959
Read of size 4 at addr ffff8880326abcc4 by task syz-executor178/5235

CPU: 0 UID: 0 PID: 5235 Comm: syz-executor178 Not tainted 6.11.0-rc5-syzkaller-00742-gfbdaffe41adc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 unix_stream_read_actor+0xa6/0xb0 net/unix/af_unix.c:2959
 unix_stream_recv_urg+0x1df/0x320 net/unix/af_unix.c:2640
 unix_stream_read_generic+0x2456/0x2520 net/unix/af_unix.c:2778
 unix_stream_recvmsg+0x22b/0x2c0 net/unix/af_unix.c:2996
 sock_recvmsg_nosec net/socket.c:1046 [inline]
 sock_recvmsg+0x22f/0x280 net/socket.c:1068
 ____sys_recvmsg+0x1db/0x470 net/socket.c:2816
 ___sys_recvmsg net/socket.c:2858 [inline]
 __sys_recvmsg+0x2f0/0x3e0 net/socket.c:2888
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5360d6b4e9
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 00 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff29b3a458 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007fff29b3a638 RCX: 00007f5360d6b4e9
RDX: 0000000000002001 RSI: 0000000020000640 RDI: 0000000000000003
RBP: 00007f5360dde610 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007fff29b3a628 R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Allocated by task 5235:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:312 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3988 [inline]
 slab_alloc_node mm/slub.c:4037 [inline]
 kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4080
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:667
 alloc_skb include/linux/skbuff.h:1320 [inline]
 alloc_skb_with_frags+0xc3/0x770 net/core/skbuff.c:6528
 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2815
 sock_alloc_send_skb include/net/sock.h:1778 [inline]
 queue_oob+0x108/0x680 net/unix/af_unix.c:2198
 unix_stream_sendmsg+0xd24/0xf80 net/unix/af_unix.c:2351
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:745
 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597
 ___sys_sendmsg net/socket.c:2651 [inline]
 __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2680
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5235:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240
 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2252 [inline]
 slab_free mm/slub.c:4473 [inline]
 kmem_cache_free+0x145/0x350 mm/slub.c:4548
 unix_stream_read_generic+0x1ef6/0x2520 net/unix/af_unix.c:2917
 unix_stream_recvmsg+0x22b/0x2c0 net/unix/af_unix.c:2996
 sock_recvmsg_nosec net/socket.c:1046 [inline]
 sock_recvmsg+0x22f/0x280 net/socket.c:1068
 __sys_recvfrom+0x256/0x3e0 net/socket.c:2255
 __do_sys_recvfrom net/socket.c:2273 [inline]
 __se_sys_recvfrom net/socket.c:2269 [inline]
 __x64_sys_recvfrom+0xde/0x100 net/socket.c:2269
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8880326abc80
 which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 68 bytes inside of
 freed 240-byte region [ffff8880326abc80, ffff8880326abd70)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x326ab
ksm flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xfdffffff(slab)
raw: 00fff00000000000 ffff88801eaee780 ffffea0000b7dc80 dead000000000003
raw: 0000000000000000 00000000800c000c 00000001fdffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 4686, tgid 4686 (udevadm), ts 32357469485, free_ts 28829011109
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1493
 prep_new_page mm/page_alloc.c:1501 [inline]
 get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3439
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4695
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x5f/0x120 mm/slub.c:2321
 allocate_slab+0x5a/0x2f0 mm/slub.c:2484
 new_slab mm/slub.c:2537 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3723
 __slab_alloc+0x58/0xa0 mm/slub.c:3813
 __slab_alloc_node mm/slub.c:3866 [inline]
 slab_alloc_node mm/slub.c:4025 [inline]
 kmem_cache_alloc_node_noprof+0x1fe/0x320 mm/slub.c:4080
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:667
 alloc_skb include/linux/skbuff.h:1320 [inline]
 alloc_uevent_skb+0x74/0x230 lib/kobject_uevent.c:289
 uevent_net_broadcast_untagged lib/kobject_uevent.c:326 [inline]
 kobject_uevent_net_broadcast+0x2fd/0x580 lib/kobject_uevent.c:410
 kobject_uevent_env+0x57d/0x8e0 lib/kobject_uevent.c:608
 kobject_synth_uevent+0x4ef/0xae0 lib/kobject_uevent.c:207
 uevent_store+0x4b/0x70 drivers/base/bus.c:633
 kernfs_fop_write_iter+0x3a1/0x500 fs/kernfs/file.c:334
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0xa72/0xc90 fs/read_write.c:590
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1094 [inline]
 free_unref_page+0xd22/0xea0 mm/page_alloc.c:2612
 kasan_depopulate_vmalloc_pte+0x74/0x90 mm/kasan/shadow.c:408
 apply_to_pte_range mm/memory.c:2797 [inline]
 apply_to_pmd_range mm/memory.c:2841 [inline]
 apply_to_pud_range mm/memory.c:2877 [inline]
 apply_to_p4d_range mm/memory.c:2913 [inline]
 __apply_to_page_range+0x8a8/0xe50 mm/memory.c:2947
 kasan_release_vmalloc+0x9a/0xb0 mm/kasan/shadow.c:525
 purge_vmap_node+0x3e3/0x770 mm/vmalloc.c:2208
 __purge_vmap_area_lazy+0x708/0xae0 mm/vmalloc.c:2290
 _vm_unmap_aliases+0x79d/0x840 mm/vmalloc.c:2885
 change_page_attr_set_clr+0x2fe/0xdb0 arch/x86/mm/pat/set_memory.c:1881
 change_page_attr_set arch/x86/mm/pat/set_memory.c:1922 [inline]
 set_memory_nx+0xf2/0x130 arch/x86/mm/pat/set_memory.c:2110
 free_init_pages arch/x86/mm/init.c:924 [inline]
 free_kernel_image_pages arch/x86/mm/init.c:943 [inline]
 free_initmem+0x79/0x110 arch/x86/mm/init.c:970
 kernel_init+0x31/0x2b0 init/main.c:1476
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Memory state around the buggy address:
 ffff8880326abb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880326abc00: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
>ffff8880326abc80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff8880326abd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
 ffff8880326abd80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb

Fixes: 93c99f21db ("af_unix: Don't stop recv(MSG_DONTWAIT) if consumed OOB skb is at the head.")
Reported-by: syzbot+8811381d455e3e9ec788@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=8811381d455e3e9ec788
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20240905193240.17565-5-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-09 17:14:27 -07:00
Abhinav Jain
6c569b77f0 selftest: af_unix: Fix kselftest compilation warnings
Change expected_buf from (const void *) to (const char *)
in function __recvpair().
This change fixes the below warnings during test compilation:

```
In file included from msg_oob.c:14:
msg_oob.c: In function ‘__recvpair’:

../../kselftest_harness.h:106:40: warning: format ‘%s’ expects argument
of type ‘char *’,but argument 6 has type ‘const void *’ [-Wformat=]

../../kselftest_harness.h:101:17: note: in expansion of macro ‘__TH_LOG’
msg_oob.c:235:17: note: in expansion of macro ‘TH_LOG’

../../kselftest_harness.h:106:40: warning: format ‘%s’ expects argument
of type ‘char *’,but argument 6 has type ‘const void *’ [-Wformat=]

../../kselftest_harness.h:101:17: note: in expansion of macro ‘__TH_LOG’
msg_oob.c:259:25: note: in expansion of macro ‘TH_LOG’
```

Fixes: d098d77232 ("selftest: af_unix: Add msg_oob.c.")
Signed-off-by: Abhinav Jain <jain.abhinav177@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20240814080743.1156166-1-jain.abhinav177@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-14 20:38:27 -07:00
Kuniyuki Iwashima
2a79651bf2 selftest: af_unix: Add test case for backtrack after finalising SCC.
syzkaller reported a KMSAN splat in __unix_walk_scc() while backtracking
edge_stack after finalising SCC.

Let's add a test case exercising the path.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Shigeru Yoshida <syoshida@redhat.com>
Link: https://patch.msgid.link/20240702160428.10153-2-syoshida@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-03 19:36:22 -07:00
Kuniyuki Iwashima
91b7186c8d selftest: af_unix: Check SIOCATMARK after every send()/recv() in msg_oob.c.
To catch regression, let's check ioctl(SIOCATMARK) after every
send() and recv() calls.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-27 12:05:01 +02:00
Kuniyuki Iwashima
e400cfa38b af_unix: Fix wrong ioctl(SIOCATMARK) when consumed OOB skb is at the head.
Even if OOB data is recv()ed, ioctl(SIOCATMARK) must return 1 when the
OOB skb is at the head of the receive queue and no new OOB data is queued.

Without fix:

  #  RUN           msg_oob.no_peek.oob ...
  # msg_oob.c:305:oob:Expected answ[0] (0) == oob_head (1)
  # oob: Test terminated by assertion
  #          FAIL  msg_oob.no_peek.oob
  not ok 2 msg_oob.no_peek.oob

With fix:

  #  RUN           msg_oob.no_peek.oob ...
  #            OK  msg_oob.no_peek.oob
  ok 2 msg_oob.no_peek.oob

Fixes: 314001f0bf ("af_unix: Add OOB support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-27 12:05:01 +02:00
Kuniyuki Iwashima
48a9983730 selftest: af_unix: Check EPOLLPRI after every send()/recv() in msg_oob.c
When OOB data is in recvq, we can detect it with epoll by checking
EPOLLPRI.

This patch add checks for EPOLLPRI after every send() and recv() in
all test cases.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-27 12:05:01 +02:00
Kuniyuki Iwashima
d02689e686 selftest: af_unix: Check SIGURG after every send() in msg_oob.c
When data is sent with MSG_OOB, SIGURG is sent to a process if the
receiver socket has set its owner to the process by ioctl(FIOSETOWN)
or fcntl(F_SETOWN).

This patch adds SIGURG check after every send(MSG_OOB) call.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-27 12:05:01 +02:00
Kuniyuki Iwashima
436352e8e5 selftest: af_unix: Add SO_OOBINLINE test cases in msg_oob.c
When SO_OOBINLINE is enabled on a socket, MSG_OOB can be recv()ed
without MSG_OOB flag, and ioctl(SIOCATMARK) will behaves differently.

This patch adds some test cases for SO_OOBINLINE.

Note the new test cases found two bugs in TCP.

  1) After reading OOB data with non-inline mode, we can re-read
     the data by setting SO_OOBINLINE.

  #  RUN           msg_oob.no_peek.inline_oob_ahead_break ...
  # msg_oob.c:146:inline_oob_ahead_break:AF_UNIX :world
  # msg_oob.c:147:inline_oob_ahead_break:TCP     :oworld
  #            OK  msg_oob.no_peek.inline_oob_ahead_break
  ok 14 msg_oob.no_peek.inline_oob_ahead_break

  2) The head OOB data is dropped if SO_OOBINLINE is disabled
     if a new OOB data is queued.

  #  RUN           msg_oob.no_peek.inline_ex_oob_drop ...
  # msg_oob.c:171:inline_ex_oob_drop:AF_UNIX :x
  # msg_oob.c:172:inline_ex_oob_drop:TCP     :y
  # msg_oob.c:146:inline_ex_oob_drop:AF_UNIX :y
  # msg_oob.c:147:inline_ex_oob_drop:TCP     :Resource temporarily unavailable
  #            OK  msg_oob.no_peek.inline_ex_oob_drop
  ok 17 msg_oob.no_peek.inline_ex_oob_drop

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-27 12:05:01 +02:00
Kuniyuki Iwashima
36893ef0b6 af_unix: Don't stop recv() at consumed ex-OOB skb.
Currently, recv() is stopped at a consumed OOB skb even if a new
OOB skb is queued and we can ignore the old OOB skb.

  >>> from socket import *
  >>> c1, c2 = socket(AF_UNIX, SOCK_STREAM)
  >>> c1.send(b'hellowor', MSG_OOB)
  8
  >>> c2.recv(1, MSG_OOB)  # consume OOB data stays at middle of recvq.
  b'r'
  >>> c1.send(b'ld', MSG_OOB)
  2
  >>> c2.recv(10)          # recv() stops at the old consumed OOB
  b'hellowo'               # should be 'hellowol'

manage_oob() should not stop recv() at the old consumed OOB skb if
there is a new OOB data queued.

Note that TCP behaviour is apparently wrong in this test case because
we can recv() the same OOB data twice.

Without fix:

  #  RUN           msg_oob.no_peek.ex_oob_ahead_break ...
  # msg_oob.c:138:ex_oob_ahead_break:AF_UNIX :hellowo
  # msg_oob.c:139:ex_oob_ahead_break:Expected:hellowol
  # msg_oob.c:141:ex_oob_ahead_break:Expected ret[0] (7) == expected_len (8)
  # ex_oob_ahead_break: Test terminated by assertion
  #          FAIL  msg_oob.no_peek.ex_oob_ahead_break
  not ok 11 msg_oob.no_peek.ex_oob_ahead_break

With fix:

  #  RUN           msg_oob.no_peek.ex_oob_ahead_break ...
  # msg_oob.c:146:ex_oob_ahead_break:AF_UNIX :hellowol
  # msg_oob.c:147:ex_oob_ahead_break:TCP     :helloworl
  #            OK  msg_oob.no_peek.ex_oob_ahead_break
  ok 11 msg_oob.no_peek.ex_oob_ahead_break

Fixes: 314001f0bf ("af_unix: Add OOB support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-27 12:05:01 +02:00
Kuniyuki Iwashima
f5ea0768a2 selftest: af_unix: Add non-TCP-compliant test cases in msg_oob.c.
While testing, I found some weird behaviour on the TCP side as well.

For example, TCP drops the preceding OOB data when queueing a new
OOB data if the old OOB data is at the head of recvq.

  #  RUN           msg_oob.no_peek.ex_oob_drop ...
  # msg_oob.c:146:ex_oob_drop:AF_UNIX :x
  # msg_oob.c:147:ex_oob_drop:TCP     :Resource temporarily unavailable
  # msg_oob.c:146:ex_oob_drop:AF_UNIX :y
  # msg_oob.c:147:ex_oob_drop:TCP     :Invalid argument
  #            OK  msg_oob.no_peek.ex_oob_drop
  ok 9 msg_oob.no_peek.ex_oob_drop

  #  RUN           msg_oob.no_peek.ex_oob_drop_2 ...
  # msg_oob.c:146:ex_oob_drop_2:AF_UNIX :x
  # msg_oob.c:147:ex_oob_drop_2:TCP     :Resource temporarily unavailable
  #            OK  msg_oob.no_peek.ex_oob_drop_2
  ok 10 msg_oob.no_peek.ex_oob_drop_2

This patch allows AF_UNIX's MSG_OOB implementation to produce different
results from TCP when operations are guarded with tcp_incompliant{}.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-27 12:05:01 +02:00
Kuniyuki Iwashima
93c99f21db af_unix: Don't stop recv(MSG_DONTWAIT) if consumed OOB skb is at the head.
Let's say a socket send()s "hello" with MSG_OOB and "world" without flags,

  >>> from socket import *
  >>> c1, c2 = socketpair(AF_UNIX)
  >>> c1.send(b'hello', MSG_OOB)
  5
  >>> c1.send(b'world')
  5

and its peer recv()s "hell" and "o".

  >>> c2.recv(10)
  b'hell'
  >>> c2.recv(1, MSG_OOB)
  b'o'

Now the consumed OOB skb stays at the head of recvq to return a correct
value for ioctl(SIOCATMARK), which is broken now and fixed by a later
patch.

Then, if peer issues recv() with MSG_DONTWAIT, manage_oob() returns NULL,
so recv() ends up with -EAGAIN.

  >>> c2.setblocking(False)  # This causes -EAGAIN even with available data
  >>> c2.recv(5)
  Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
  BlockingIOError: [Errno 11] Resource temporarily unavailable

However, next recv() will return the following available data, "world".

  >>> c2.recv(5)
  b'world'

When the consumed OOB skb is at the head of the queue, we need to fetch
the next skb to fix the weird behaviour.

Note that the issue does not happen without MSG_DONTWAIT because we can
retry after manage_oob().

This patch also adds a test case that covers the issue.

Without fix:

  #  RUN           msg_oob.no_peek.ex_oob_break ...
  # msg_oob.c:134:ex_oob_break:AF_UNIX :Resource temporarily unavailable
  # msg_oob.c:135:ex_oob_break:Expected:ld
  # msg_oob.c:137:ex_oob_break:Expected ret[0] (-1) == expected_len (2)
  # ex_oob_break: Test terminated by assertion
  #          FAIL  msg_oob.no_peek.ex_oob_break
  not ok 8 msg_oob.no_peek.ex_oob_break

With fix:

  #  RUN           msg_oob.no_peek.ex_oob_break ...
  #            OK  msg_oob.no_peek.ex_oob_break
  ok 8 msg_oob.no_peek.ex_oob_break

Fixes: 314001f0bf ("af_unix: Add OOB support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-27 12:05:01 +02:00
Kuniyuki Iwashima
b94038d841 af_unix: Stop recv(MSG_PEEK) at consumed OOB skb.
After consuming OOB data, recv() reading the preceding data must break at
the OOB skb regardless of MSG_PEEK.

Currently, MSG_PEEK does not stop recv() for AF_UNIX, and the behaviour is
not compliant with TCP.

  >>> from socket import *
  >>> c1, c2 = socketpair(AF_UNIX)
  >>> c1.send(b'hello', MSG_OOB)
  5
  >>> c1.send(b'world')
  5
  >>> c2.recv(1, MSG_OOB)
  b'o'
  >>> c2.recv(9, MSG_PEEK)  # This should return b'hell'
  b'hellworld'              # even with enough buffer.

Let's fix it by returning NULL for consumed skb and unlinking it only if
MSG_PEEK is not specified.

This patch also adds test cases that add recv(MSG_PEEK) before each recv().

Without fix:

  #  RUN           msg_oob.peek.oob_ahead_break ...
  # msg_oob.c:134:oob_ahead_break:AF_UNIX :hellworld
  # msg_oob.c:135:oob_ahead_break:Expected:hell
  # msg_oob.c:137:oob_ahead_break:Expected ret[0] (9) == expected_len (4)
  # oob_ahead_break: Test terminated by assertion
  #          FAIL  msg_oob.peek.oob_ahead_break
  not ok 13 msg_oob.peek.oob_ahead_break

With fix:

  #  RUN           msg_oob.peek.oob_ahead_break ...
  #            OK  msg_oob.peek.oob_ahead_break
  ok 13 msg_oob.peek.oob_ahead_break

Fixes: 314001f0bf ("af_unix: Add OOB support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-27 12:05:00 +02:00
Kuniyuki Iwashima
d098d77232 selftest: af_unix: Add msg_oob.c.
AF_UNIX's MSG_OOB functionality lacked thorough testing, and we found
some bizarre behaviour.

The new selftest validates every MSG_OOB operation against TCP as a
reference implementation.

This patch adds only a few tests with basic send() and recv() that
do not fail.

The following patches will add more test cases for SO_OOBINLINE, SIGURG,
EPOLLPRI, and SIOCATMARK.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-27 12:05:00 +02:00
Kuniyuki Iwashima
7d139181a8 selftest: af_unix: Remove test_unix_oob.c.
test_unix_oob.c does not fully cover AF_UNIX's MSG_OOB functionality,
thus there are discrepancies between TCP behaviour.

Also, the test uses fork() to create message producer, and it's not
easy to understand and add more test cases.

Let's remove test_unix_oob.c and rewrite a new test.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-27 12:05:00 +02:00
Kuniyuki Iwashima
11b006d689 selftest: af_unix: Add Kconfig file.
diag_uid selftest failed on NIPA where the received nlmsg_type is
NLMSG_ERROR [0] because CONFIG_UNIX_DIAG is not set [1] by default
and sock_diag_lock_handler() failed to load the module.

  # # Starting 2 tests from 2 test cases.
  # #  RUN           diag_uid.uid.1 ...
  # # diag_uid.c:159:1:Expected nlh->nlmsg_type (2) == SOCK_DIAG_BY_FAMILY (20)
  # # 1: Test terminated by assertion
  # #          FAIL  diag_uid.uid.1
  # not ok 1 diag_uid.uid.1

Let's add all AF_UNIX Kconfig to the config file under af_unix dir
so that NIPA consumes it.

Fixes: ac011361bd ("af_unix: Add test for sock_diag and UDIAG_SHOW_UID.")
Link: https://netdev-3.bots.linux.dev/vmksft-net/results/644841/104-diag-uid/stdout [0]
Link: https://netdev-3.bots.linux.dev/vmksft-net/results/644841/config [1]
Reported-by: Jakub Kicinski <kuba@kernel.org>
Closes: https://lore.kernel.org/netdev/20240617073033.0cbb829d@kernel.org/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-21 14:26:11 +01:00
Kuniyuki Iwashima
e060e433e5 selftest: af_unix: Make SCM_RIGHTS into OOB data.
scm_rights.c covers various test cases for inflight file descriptors
and garbage collector for AF_UNIX sockets.

Currently, SCM_RIGHTS messages are sent with 3-bytes string, and it's
not good for MSG_OOB cases, as SCM_RIGTS cmsg goes with the first 2-bytes,
which is non-OOB data.

Let's send SCM_RIGHTS messages with 1-byte character to pack SCM_RIGHTS
into OOB data.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-21 13:42:08 +02:00
Kuniyuki Iwashima
2aa0cff26e selftest: af_unix: Test GC for SCM_RIGHTS.
This patch adds test cases to verify the new GC.

We run each test for the following cases:

  * SOCK_DGRAM
  * SOCK_STREAM without embryo socket
  * SOCK_STREAM without embryo socket + MSG_OOB
  * SOCK_STREAM with embryo sockets
  * SOCK_STREAM with embryo sockets + MSG_OOB

Before and after running each test case, we ensure that there is
no AF_UNIX socket left in the netns by reading /proc/net/protocols.

We cannot use /proc/net/unix and UNIX_DIAG because the embryo socket
does not show up there.

Each test creates multiple sockets in an array.  We pass sockets in
the even index using the peer sockets in the odd index.

So, send_fd(0, 1) actually sends fd[0] to fd[2] via fd[0 + 1].

  Test 1 : A <-> A
  Test 2 : A <-> B
  Test 3 : A -> B -> C <- D
           ^.___|___.'    ^
                `---------'

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240325202425.60930-16-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-03-29 08:28:46 -07:00
Willem de Bruijn
59fef379d4 selftests/net: unix: fix unused variable compiler warning
Remove an unused variable.

    diag_uid.c:151:24:
    error: unused variable 'udr'
    [-Werror,-Wunused-variable]

Fixes: ac011361bd ("af_unix: Add test for sock_diag and UDIAG_SHOW_UID.")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20231124171645.1011043-4-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-11-27 18:12:07 -08:00
zhujun2
3c4fe89878 selftests: net: remove unused variables
These variables are never referenced in the code, just remove them

Signed-off-by: zhujun2 <zhujun2@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-10-16 09:20:08 +01:00
Alexander Mikhalitsyn
ec80f48825 selftests: net: add SCM_PIDFD / SO_PEERPIDFD test
Basic test to check consistency between:
- SCM_CREDENTIALS and SCM_PIDFD
- SO_PEERCRED and SO_PEERPIDFD

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: David Ahern <dsahern@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Kuniyuki Iwashima <kuniyu@amazon.com>
Cc: linux-kernel@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-06-12 10:45:50 +01:00
Mirsad Goran Todorovac
7d6ceeb187 af_unix: selftest: Fix the size of the parameter to connect()
Adjust size parameter in connect() to match the type of the parameter, to
fix "No such file or directory" error in selftests/net/af_unix/
test_oob_unix.c:127.

The existing code happens to work provided that the autogenerated pathname
is shorter than sizeof (struct sockaddr), which is why it hasn't been
noticed earlier.

Visible from the trace excerpt:

bind(3, {sa_family=AF_UNIX, sun_path="unix_oob_453059"}, 110) = 0
clone(child_stack=NULL, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x7fa6a6577a10) = 453060
[pid <child>] connect(6, {sa_family=AF_UNIX, sun_path="unix_oob_45305"}, 16) = -1 ENOENT (No such file or directory)

BUG: The filename is trimmed to sizeof (struct sockaddr).

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Cc: Florian Westphal <fw@strlen.de>
Reviewed-by: Florian Westphal <fw@strlen.de>
Fixes: 314001f0bf ("af_unix: Add OOB support")
Signed-off-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-09 08:16:13 +00:00
Kuniyuki Iwashima
ac011361bd af_unix: Add test for sock_diag and UDIAG_SHOW_UID.
The test prog dumps a single AF_UNIX socket's UID with and without
unshare(CLONE_NEWUSER) and checks if it matches the result of getuid().

Without the preceding patch, the test prog is killed by a NULL deref
in sk_diag_dump_uid().

  # ./diag_uid
  TAP version 13
  1..2
  # Starting 2 tests from 3 test cases.
  #  RUN           diag_uid.uid.1 ...
  BUG: kernel NULL pointer dereference, address: 0000000000000270
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 105212067 P4D 105212067 PUD 1051fe067 PMD 0
  Oops: 0000 [#1] PREEMPT SMP NOPTI
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.amzn2022.0.1 04/01/2014
  RIP: 0010:sk_diag_fill (./include/net/sock.h:920 net/unix/diag.c:119 net/unix/diag.c:170)
  ...
  # 1: Test terminated unexpectedly by signal 9
  #          FAIL  diag_uid.uid.1
  not ok 1 diag_uid.uid.1
  #  RUN           diag_uid.uid_unshare.1 ...
  # 1: Test terminated by timeout
  #          FAIL  diag_uid.uid_unshare.1
  not ok 2 diag_uid.uid_unshare.1
  # FAILED: 0 / 2 tests passed.
  # Totals: pass:0 fail:2 xfail:0 xpass:0 skip:0 error:0

With the patch, the test succeeds.

  # ./diag_uid
  TAP version 13
  1..2
  # Starting 2 tests from 3 test cases.
  #  RUN           diag_uid.uid.1 ...
  #            OK  diag_uid.uid.1
  ok 1 diag_uid.uid.1
  #  RUN           diag_uid.uid_unshare.1 ...
  #            OK  diag_uid.uid_unshare.1
  ok 2 diag_uid.uid_unshare.1
  # PASSED: 2 / 2 tests passed.
  # Totals: pass:2 fail:0 xfail:0 xpass:0 skip:0 error:0

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-12-01 10:32:20 +01:00
Kuniyuki Iwashima
f12b86c0d6 selftests: net: af_unix: Fix a build error of unix_connect.c.
This patch fixes a build error reported in the link. [0]

  unix_connect.c: In function ‘unix_connect_test’:
  unix_connect.c:115:55: error: expected identifier before ‘(’ token
   #define offsetof(type, member) ((size_t)&((type *)0)->(member))
                                                       ^
  unix_connect.c:128:12: note: in expansion of macro ‘offsetof’
    addrlen = offsetof(struct sockaddr_un, sun_path) + variant->len;
              ^~~~~~~~

We can fix this by removing () around member, but checkpatch will complain
about it, and the root cause of the build failure is that I followed the
warning and fixed this in the v2 -> v3 change of the blamed commit. [1]

  CHECK: Macro argument 'member' may be better as '(member)' to avoid precedence issues
  #33: FILE: tools/testing/selftests/net/af_unix/unix_connect.c:115:
  +#define offsetof(type, member) ((size_t)&((type *)0)->member)

To avoid this warning, let's use offsetof() defined in stddef.h instead.

[0]: https://lore.kernel.org/linux-mm/202207182205.FrkMeDZT-lkp@intel.com/
[1]: https://lore.kernel.org/netdev/20220702154818.66761-1-kuniyu@amazon.com/

Fixes: e95ab1d852 ("selftests: net: af_unix: Test connect() with different netns.")
Reported-by: kernel test robot <lkp@intel.com>
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20220720005750.16600-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-20 21:02:15 -07:00
Kuniyuki Iwashima
e95ab1d852 selftests: net: af_unix: Test connect() with different netns.
This patch add a test that checks connect()ivity between two sockets:

    unnamed socket -> bound socket
                      * SOCK_STREAM or SOCK_DGRAM
                      * pathname or abstract
                      * same or different netns

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-07-05 11:34:58 +02:00
Kuniyuki Iwashima
d9a232d435 af_unix: Support POLLPRI for OOB.
The commit 314001f0bf ("af_unix: Add OOB support") introduced OOB for
AF_UNIX, but it lacks some changes for POLLPRI.  Let's add the missing
piece.

In the selftest, normal datagrams are sent followed by OOB data, so this
commit replaces `POLLIN | POLLPRI` with just `POLLPRI` in the first test
case.

Fixes: 314001f0bf ("af_unix: Add OOB support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-18 13:30:52 +00:00
Shuah Khan
e30cd812df selftests: net: af_unix: Fix makefile to use TEST_GEN_PROGS
Makefile uses TEST_PROGS instead of TEST_GEN_PROGS to define
executables. TEST_PROGS is for shell scripts that need to be
installed and run by the common lib.mk framework. The common
framework doesn't touch TEST_PROGS when it does build and clean.

As a result "make kselftest-clean" and "make clean" fail to remove
executables. Run and install work because the common framework runs
and installs TEST_PROGS. Build works because the Makefile defines
"all" rule which is unnecessary if TEST_GEN_PROGS is used.

Use TEST_GEN_PROGS so the common framework can handle build/run/
install/clean properly.

Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-19 13:22:18 +01:00
Shuah Khan
48514a2233 selftests: net: af_unix: Fix incorrect args in test result msg
Fix the args to fprintf(). Splitting the message ends up passing
incorrect arg for "sigurg %d" and an extra arg overall. The test
result message ends up incorrect.

test_unix_oob.c: In function ‘main’:
test_unix_oob.c:274:43: warning: format ‘%d’ expects argument of type ‘int’, but argument 3 has type ‘char *’ [-Wformat=]
  274 |   fprintf(stderr, "Test 3 failed, sigurg %d len %d OOB %c ",
      |                                          ~^
      |                                           |
      |                                           int
      |                                          %s
  275 |   "atmark %d\n", signal_recvd, len, oob, atmark);
      |   ~~~~~~~~~~~~~
      |   |
      |   char *
test_unix_oob.c:274:19: warning: too many arguments for format [-Wformat-extra-args]
  274 |   fprintf(stderr, "Test 3 failed, sigurg %d len %d OOB %c ",

Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-19 13:15:19 +01:00
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