[ Upstream commit 2aab4b96900272885bc157f8b236abf1cdc02e08 ]
syzbot reported struct pid leak [1].
Issue is that queue_oob() calls maybe_add_creds() which potentially
holds a reference on a pid.
But skb->destructor is not set (either directly or by calling
unix_scm_to_skb())
This means that subsequent kfree_skb() or consume_skb() would leak
this reference.
In this fix, I chose to fully support scm even for the OOB message.
[1]
BUG: memory leak
unreferenced object 0xffff8881053e7f80 (size 128):
comm "syz-executor242", pid 5066, jiffies 4294946079 (age 13.220s)
hex dump (first 32 bytes):
01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff812ae26a>] alloc_pid+0x6a/0x560 kernel/pid.c:180
[<ffffffff812718df>] copy_process+0x169f/0x26c0 kernel/fork.c:2285
[<ffffffff81272b37>] kernel_clone+0xf7/0x610 kernel/fork.c:2684
[<ffffffff812730cc>] __do_sys_clone+0x7c/0xb0 kernel/fork.c:2825
[<ffffffff849ad699>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff849ad699>] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
[<ffffffff84a0008b>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
Fixes: 314001f0bf92 ("af_unix: Add OOB support")
Reported-by: syzbot+7699d9e5635c10253a27@syzkaller.appspotmail.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Rao Shoaib <rao.shoaib@oracle.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230307164530.771896-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d900f3d20cc3169ce42ec72acc850e662a4d4db2 ]
When the buffer length of the recvmsg system call is 0, we got the
flollowing soft lockup problem:
watchdog: BUG: soft lockup - CPU#3 stuck for 27s! [a.out:6149]
CPU: 3 PID: 6149 Comm: a.out Kdump: loaded Not tainted 6.2.0+ #30
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
RIP: 0010:remove_wait_queue+0xb/0xc0
Code: 5e 41 5f c3 cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 0f 1f 44 00 00 41 57 <41> 56 41 55 41 54 55 48 89 fd 53 48 89 f3 4c 8d 6b 18 4c 8d 73 20
RSP: 0018:ffff88811b5978b8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88811a7d3780 RCX: ffffffffb7a4d768
RDX: dffffc0000000000 RSI: ffff88811b597908 RDI: ffff888115408040
RBP: 1ffff110236b2f1b R08: 0000000000000000 R09: ffff88811a7d37e7
R10: ffffed10234fa6fc R11: 0000000000000001 R12: ffff88811179b800
R13: 0000000000000001 R14: ffff88811a7d38a8 R15: ffff88811a7d37e0
FS: 00007f6fb5398740(0000) GS:ffff888237180000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000000 CR3: 000000010b6ba002 CR4: 0000000000370ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
tcp_msg_wait_data+0x279/0x2f0
tcp_bpf_recvmsg_parser+0x3c6/0x490
inet_recvmsg+0x280/0x290
sock_recvmsg+0xfc/0x120
____sys_recvmsg+0x160/0x3d0
___sys_recvmsg+0xf0/0x180
__sys_recvmsg+0xea/0x1a0
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
The logic in tcp_bpf_recvmsg_parser is as follows:
msg_bytes_ready:
copied = sk_msg_recvmsg(sk, psock, msg, len, flags);
if (!copied) {
wait data;
goto msg_bytes_ready;
}
In this case, "copied" always is 0, the infinite loop occurs.
According to the Linux system call man page, 0 should be returned in this
case. Therefore, in tcp_bpf_recvmsg_parser(), if the length is 0, directly
return. Also modify several other functions with the same problem.
Fixes: 1f5be6b3b063 ("udp: Implement udp_bpf_recvmsg() for sockmap")
Fixes: 9825d866ce0d ("af_unix: Implement unix_dgram_bpf_recvmsg()")
Fixes: c5d2177a72a1 ("bpf, sockmap: Fix race in ingress receive verdict with redirect to self")
Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Liu Jian <liujian56@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Cc: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20230303080946.1146638-1-liujian56@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
There is a race resulting in alive SOCK_SEQPACKET socket
may change its state from TCP_ESTABLISHED to TCP_CLOSE:
unix_release_sock(peer) unix_dgram_sendmsg(sk)
sock_orphan(peer)
sock_set_flag(peer, SOCK_DEAD)
sock_alloc_send_pskb()
if !(sk->sk_shutdown & SEND_SHUTDOWN)
OK
if sock_flag(peer, SOCK_DEAD)
sk->sk_state = TCP_CLOSE
sk->sk_shutdown = SHUTDOWN_MASK
After that socket sk remains almost normal: it is able to connect, listen, accept
and recvmsg, while it can't sendmsg.
Since this is the only possibility for alive SOCK_SEQPACKET to change
the state in such way, we should better fix this strange and potentially
danger corner case.
Note, that we will return EPIPE here like this is normally done in sock_alloc_send_pskb().
Originally used ECONNREFUSED looks strange, since it's strange to return
a specific retval in dependence of race in kernel, when user can't affect on this.
Also, move TCP_CLOSE assignment for SOCK_DGRAM sockets under state lock
to fix race with unix_dgram_connect():
unix_dgram_connect(other) unix_dgram_sendmsg(sk)
unix_peer(sk) = NULL
unix_state_unlock(sk)
unix_state_double_lock(sk, other)
sk->sk_state = TCP_ESTABLISHED
unix_peer(sk) = other
unix_state_double_unlock(sk, other)
sk->sk_state = TCP_CLOSED
This patch fixes both of these races.
Fixes: 83301b5367a9 ("af_unix: Set TCP_ESTABLISHED for datagram sockets too")
Signed-off-by: Kirill Tkhai <tkhai@ya.ru>
Link: https://lore.kernel.org/r/135fda25-22d5-837a-782b-ceee50e19844@ya.ru
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
If register unix_stream_proto returns error, unix_dgram_proto needs
be unregistered.
Fixes: 94531cfcbe79 ("af_unix: Add unix_stream_proto for sockmap")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Wei Chen reported a NULL deref in sk_user_ns() [0][1], and Paolo diagnosed
the root cause: in unix_diag_get_exact(), the newly allocated skb does not
have sk. [2]
We must get the user_ns from the NETLINK_CB(in_skb).sk and pass it to
sk_diag_fill().
[0]:
BUG: kernel NULL pointer dereference, address: 0000000000000270
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 12bbce067 P4D 12bbce067 PUD 12bc40067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
CPU: 0 PID: 27942 Comm: syz-executor.0 Not tainted 6.1.0-rc5-next-20221118 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.13.0-48-gd9c812dda519-prebuilt.qemu.org 04/01/2014
RIP: 0010:sk_user_ns include/net/sock.h:920 [inline]
RIP: 0010:sk_diag_dump_uid net/unix/diag.c:119 [inline]
RIP: 0010:sk_diag_fill+0x77d/0x890 net/unix/diag.c:170
Code: 89 ef e8 66 d4 2d fd c7 44 24 40 00 00 00 00 49 8d 7c 24 18 e8
54 d7 2d fd 49 8b 5c 24 18 48 8d bb 70 02 00 00 e8 43 d7 2d fd <48> 8b
9b 70 02 00 00 48 8d 7b 10 e8 33 d7 2d fd 48 8b 5b 10 48 8d
RSP: 0018:ffffc90000d67968 EFLAGS: 00010246
RAX: ffff88812badaa48 RBX: 0000000000000000 RCX: ffffffff840d481d
RDX: 0000000000000465 RSI: 0000000000000000 RDI: 0000000000000270
RBP: ffffc90000d679a8 R08: 0000000000000277 R09: 0000000000000000
R10: 0001ffffffffffff R11: 0001c90000d679a8 R12: ffff88812ac03800
R13: ffff88812c87c400 R14: ffff88812ae42210 R15: ffff888103026940
FS: 00007f08b4e6f700(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000270 CR3: 000000012c58b000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
unix_diag_get_exact net/unix/diag.c:285 [inline]
unix_diag_handler_dump+0x3f9/0x500 net/unix/diag.c:317
__sock_diag_cmd net/core/sock_diag.c:235 [inline]
sock_diag_rcv_msg+0x237/0x250 net/core/sock_diag.c:266
netlink_rcv_skb+0x13e/0x250 net/netlink/af_netlink.c:2564
sock_diag_rcv+0x24/0x40 net/core/sock_diag.c:277
netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
netlink_unicast+0x5e9/0x6b0 net/netlink/af_netlink.c:1356
netlink_sendmsg+0x739/0x860 net/netlink/af_netlink.c:1932
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg net/socket.c:734 [inline]
____sys_sendmsg+0x38f/0x500 net/socket.c:2476
___sys_sendmsg net/socket.c:2530 [inline]
__sys_sendmsg+0x197/0x230 net/socket.c:2559
__do_sys_sendmsg net/socket.c:2568 [inline]
__se_sys_sendmsg net/socket.c:2566 [inline]
__x64_sys_sendmsg+0x42/0x50 net/socket.c:2566
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x4697f9
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f08b4e6ec48 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000077bf80 RCX: 00000000004697f9
RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003
RBP: 00000000004d29e9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000077bf80
R13: 0000000000000000 R14: 000000000077bf80 R15: 00007ffdb36bc6c0
</TASK>
Modules linked in:
CR2: 0000000000000270
[1]: https://lore.kernel.org/netdev/CAO4mrfdvyjFpokhNsiwZiP-wpdSD0AStcJwfKcKQdAALQ9_2Qw@mail.gmail.com/
[2]: https://lore.kernel.org/netdev/e04315e7c90d9a75613f3993c2baf2d344eef7eb.camel@redhat.com/
Fixes: cae9910e7344 ("net: Add UNIX_DIAG_UID to Netlink UNIX socket diagnostics.")
Reported-by: syzbot <syzkaller@googlegroups.com>
Reported-by: Wei Chen <harperchen1110@gmail.com>
Diagnosed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
sockmap replaces ->sk_prot with its own callbacks, we should remove
SOCK_SUPPORT_ZC as the new proto doesn't support msghdr::ubuf_info.
Cc: <stable@vger.kernel.org> # 6.0
Reported-by: Jakub Kicinski <kuba@kernel.org>
Fixes: e993ffe3da4bc ("net: flag sockets supporting msghdr originated zerocopy")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pull more random number generator updates from Jason Donenfeld:
"This time with some large scale treewide cleanups.
The intent of this pull is to clean up the way callers fetch random
integers. The current rules for doing this right are:
- If you want a secure or an insecure random u64, use get_random_u64()
- If you want a secure or an insecure random u32, use get_random_u32()
The old function prandom_u32() has been deprecated for a while
now and is just a wrapper around get_random_u32(). Same for
get_random_int().
- If you want a secure or an insecure random u16, use get_random_u16()
- If you want a secure or an insecure random u8, use get_random_u8()
- If you want secure or insecure random bytes, use get_random_bytes().
The old function prandom_bytes() has been deprecated for a while
now and has long been a wrapper around get_random_bytes()
- If you want a non-uniform random u32, u16, or u8 bounded by a
certain open interval maximum, use prandom_u32_max()
I say "non-uniform", because it doesn't do any rejection sampling
or divisions. Hence, it stays within the prandom_*() namespace, not
the get_random_*() namespace.
I'm currently investigating a "uniform" function for 6.2. We'll see
what comes of that.
By applying these rules uniformly, we get several benefits:
- By using prandom_u32_max() with an upper-bound that the compiler
can prove at compile-time is ≤65536 or ≤256, internally
get_random_u16() or get_random_u8() is used, which wastes fewer
batched random bytes, and hence has higher throughput.
- By using prandom_u32_max() instead of %, when the upper-bound is
not a constant, division is still avoided, because
prandom_u32_max() uses a faster multiplication-based trick instead.
- By using get_random_u16() or get_random_u8() in cases where the
return value is intended to indeed be a u16 or a u8, we waste fewer
batched random bytes, and hence have higher throughput.
This series was originally done by hand while I was on an airplane
without Internet. Later, Kees and I worked on retroactively figuring
out what could be done with Coccinelle and what had to be done
manually, and then we split things up based on that.
So while this touches a lot of files, the actual amount of code that's
hand fiddled is comfortably small"
* tag 'random-6.1-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random:
prandom: remove unused functions
treewide: use get_random_bytes() when possible
treewide: use get_random_u32() when possible
treewide: use get_random_{u8,u16}() when possible, part 2
treewide: use get_random_{u8,u16}() when possible, part 1
treewide: use prandom_u32_max() when possible, part 2
treewide: use prandom_u32_max() when possible, part 1
Pull more io_uring updates from Jens Axboe:
"A collection of fixes that ended up either being later than the
initial pull, or dependent on multiple branches (6.0-late being one of
them) and hence deferred purposely. This contains:
- Cleanup fixes for the single submitter late 6.0 change, which we
pushed to 6.1 to keep the 6.0 changes small (Dylan, Pavel)
- Fix for IORING_OP_CONNECT not handling -EINPROGRESS correctly (me)
- Ensure that the zc sendmsg variant gets audited correctly (me)
- Regression fix from this merge window where kiocb_end_write()
doesn't always gets called, which can cause issues with fs freezing
(me)
- Registered files SCM handling fix (Pavel)
- Regression fix for big sqe dumping in fdinfo (Pavel)
- Registered buffers accounting fix (Pavel)
- Remove leftover notification structures, we killed them off late in
6.0 (Pavel)
- Minor optimizations (Pavel)
- Cosmetic variable shadowing fix (Stefan)"
* tag 'io_uring-6.1-2022-10-13' of git://git.kernel.dk/linux:
io_uring/rw: ensure kiocb_end_write() is always called
io_uring: fix fdinfo sqe offsets calculation
io_uring: local variable rw shadows outer variable in io_write
io_uring/opdef: remove 'audit_skip' from SENDMSG_ZC
io_uring: optimise locking for local tw with submit_wait
io_uring: remove redundant memory barrier in io_req_local_work_add
io_uring/net: handle -EINPROGRESS correct for IORING_OP_CONNECT
io_uring: remove notif leftovers
io_uring: correct pinned_vm accounting
io_uring/af_unix: defer registered files gc to io_uring release
io_uring: limit registration w/ SINGLE_ISSUER
io_uring: remove io_register_submitter
io_uring: simplify __io_uring_add_tctx_node
Instead of putting io_uring's registered files in unix_gc() we want it
to be done by io_uring itself. The trick here is to consider io_uring
registered files for cycle detection but not actually putting them down.
Because io_uring can't register other ring instances, this will remove
all refs to the ring file triggering the ->release path and clean up
with io_ring_ctx_free().
Cc: stable@vger.kernel.org
Fixes: 6b06314c47e1 ("io_uring: add file set registration")
Reported-and-tested-by: David Bouman <dbouman03@gmail.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
[axboe: add kerneldoc comment to skb, fold in skb leak fix]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The prandom_u32() function has been a deprecated inline wrapper around get_random_u32() for several releases now, and compiles down to the exact same code. Replace the deprecated wrapper with a direct call to the real function. The same also applies to get_random_int(), which is just a wrapper around get_random_u32(). This was done as a basic find and replace. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> # for sch_cake Acked-by: Chuck Lever <chuck.lever@oracle.com> # for nfsd Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # for thunderbolt Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Acked-by: Helge Deller <deller@gmx.de> # for parisc Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>