This is needed to prevent sk_user_data being overwritten.
The check is done under the callback lock. This should prevent
a socket from being attached twice to a KCM mux. It also prevents
a socket from being attached for other use cases of sk_user_data
as long as the other cases set sk_user_data under the lock.
Followup work is needed to unify all the use cases of sk_user_data
to use the same locking.
Reported-by: syzbot+114b15f2be420a8886c3@syzkaller.appspotmail.com
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Signed-off-by: Tom Herbert <tom@quantonium.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
TCP sockets for IPv4 and IPv6 that are not listeners or in closed
stated are allowed to be attached to a KCM mux.
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Reported-by: syzbot+8865eaff7f9acd593945@syzkaller.appspotmail.com
Signed-off-by: Tom Herbert <tom@quantonium.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This changes calling conventions (and simplifies the hell out
the callers). New rules: once struct socket had been passed
to sock_alloc_file(), it's been consumed either by struct file
or by sock_release() done by sock_alloc_file(). Either way
the caller should not do sock_release() after that point.
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
1) it's fput() or sock_release(), not both
2) don't do fd_install() until the last failure exit.
3) not a bug per se, but... don't attach socket to struct file
until it's set up.
Take reserving descriptor into the caller, move fd_install() to the
caller, sanitize failure exits and calling conventions.
Cc: stable@vger.kernel.org # v4.6+
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Files removed in 'net-next' had their license header updated
in 'net'. We take the remove from 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
IS_ERR() already implies unlikely(), so it can be omitted.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
syzkaller had no problem to trigger a deadlock, attaching a KCM socket
to another one (or itself). (original syzkaller report was a very
confusing lockdep splat during a sendmsg())
It seems KCM claims to only support TCP, but no enforcement is done,
so we might need to add additional checks.
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Tom Herbert <tom@quantonium.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Generalize strparser from more than just being used in conjunction
with read_sock. strparser will also be used in the send path with
zero proxy. The primary change is to create strp_process function
that performs the critical processing on skbs. The documentation
is also updated to reflect the new uses.
Signed-off-by: Tom Herbert <tom@quantonium.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
struct kcm_clone only contains fd, and kcm_clone() only
writes this struct, so there is no need to copy it from user.
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is no reason to continue after a copy_from_user()
failure.
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix up affected files that include this signal functionality via sched.h.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In commit 98e3862ca2 ("kcm: fix 0-length case for kcm_sendmsg()")
I tried to avoid skb allocation for 0-length case, but missed
a check for NULL pointer in the non EOR case.
Fixes: 98e3862ca2 ("kcm: fix 0-length case for kcm_sendmsg()")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Dmitry reported a kernel warning:
WARNING: CPU: 3 PID: 2936 at net/kcm/kcmsock.c:627
kcm_write_msgs+0x12e3/0x1b90 net/kcm/kcmsock.c:627
CPU: 3 PID: 2936 Comm: a.out Not tainted 4.10.0-rc6+ #209
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:15 [inline]
dump_stack+0x2ee/0x3ef lib/dump_stack.c:51
panic+0x1fb/0x412 kernel/panic.c:179
__warn+0x1c4/0x1e0 kernel/panic.c:539
warn_slowpath_null+0x2c/0x40 kernel/panic.c:582
kcm_write_msgs+0x12e3/0x1b90 net/kcm/kcmsock.c:627
kcm_sendmsg+0x163a/0x2200 net/kcm/kcmsock.c:1029
sock_sendmsg_nosec net/socket.c:635 [inline]
sock_sendmsg+0xca/0x110 net/socket.c:645
sock_write_iter+0x326/0x600 net/socket.c:848
new_sync_write fs/read_write.c:499 [inline]
__vfs_write+0x483/0x740 fs/read_write.c:512
vfs_write+0x187/0x530 fs/read_write.c:560
SYSC_write fs/read_write.c:607 [inline]
SyS_write+0xfb/0x230 fs/read_write.c:599
entry_SYSCALL_64_fastpath+0x1f/0xc2
when calling syscall(__NR_write, sock2, 0x208aaf27ul, 0x0ul) on a KCM
seqpacket socket. It appears that kcm_sendmsg() does not handle len==0
case correctly, which causes an empty skb is allocated and queued.
Fix this by skipping the skb allocation for len==0 case.
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull VFS splice updates from Al Viro:
"There's a bunch of branches this cycle, both mine and from other folks
and I'd rather send pull requests separately.
This one is the conversion of ->splice_read() to ITER_PIPE iov_iter
(and introduction of such). Gets rid of a lot of code in fs/splice.c
and elsewhere; there will be followups, but these are for the next
cycle... Some pipe/splice-related cleanups from Miklos in the same
branch as well"
* 'work.splice_read' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
pipe: fix comment in pipe_buf_operations
pipe: add pipe_buf_steal() helper
pipe: add pipe_buf_confirm() helper
pipe: add pipe_buf_release() helper
pipe: add pipe_buf_get() helper
relay: simplify relay_file_read()
switch default_file_splice_read() to use of pipe-backed iov_iter
switch generic_file_splice_read() to use of ->read_iter()
new iov_iter flavour: pipe-backed
fuse_dev_splice_read(): switch to add_to_pipe()
skb_splice_bits(): get rid of callback
new helper: add_to_pipe()
splice: lift pipe_lock out of splice_to_pipe()
splice: switch get_iovec_page_array() to iov_iter
splice_to_pipe(): don't open-code wakeup_pipe_readers()
consistent treatment of EFAULT on O_DIRECT read/write
since pipe_lock is the outermost now, we don't need to drop/regain
socket locks around the call of splice_to_pipe() from skb_splice_bits(),
which kills the need to have a socket-specific callback; we can just
call splice_to_pipe() and be done with that.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Conflicts:
drivers/net/ethernet/mediatek/mtk_eth_soc.c
drivers/net/ethernet/qlogic/qed/qed_dcbx.c
drivers/net/phy/Kconfig
All conflicts were cases of overlapping commits.
Signed-off-by: David S. Miller <davem@davemloft.net>
Dmitry reported a double free on kcm socket, which could
be easily reproduced by:
#include <unistd.h>
#include <sys/syscall.h>
int main()
{
int fd = syscall(SYS_socket, 0x29ul, 0x5ul, 0x0ul, 0, 0, 0);
syscall(SYS_ioctl, fd, 0x89e2ul, 0x20a98000ul, 0, 0, 0);
return 0;
}
This is because on the error path, after we install
the new socket file, we call sock_release() to clean
up the socket, which leaves the fd pointing to a freed
socket. Fix this by calling sys_close() on that fd
directly.
Fixes: ab7ac4eb98 ("kcm: Kernel Connection Multiplexor module")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
kcm and strparser need to work with any type of stream socket not just
TCP. Eliminate references to TCP and call generic proto_ops functions of
read_sock and peek_len. Also in strp_init check if the socket support
the proto_ops read_sock and peek_len.
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Lock the lower socket in kcm_unattach. Release during call to strp_done
since that function cancels the RX timers and work queue with sync.
Also added some status information in psock reporting.
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adapt KCM to use the stream parser. This mostly involves removing
the RX handling and setting up the strparser using the interface.
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The check for a -ve error is redundant, remove it and just
immediately return the return value from the call to
seq_open_net.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since bpf_prog_get() and program type check is used in a couple of places,
refactor this into a small helper function that we can make use of. Since
the non RO prog->aux part is not used in performance critical paths and a
program destruction via RCU is rather very unlikley when doing the put, we
shouldn't have an issue just doing the bpf_prog_get() + prog->type != type
check, but actually not taking the ref at all (due to being in fdget() /
fdput() section of the bpf fd) is even cleaner and makes the diff smaller
as well, so just go for that. Callsites are changed to make use of the new
helper where possible.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Every open of /proc/net/kcm leaks 16 bytes of memory as is reported by
kmemleak:
unreferenced object 0xffff88059c0e3458 (size 192):
comm "cat", pid 1401, jiffies 4294935742 (age 310.720s)
hex dump (first 32 bytes):
28 45 71 96 05 88 ff ff 00 10 00 00 00 00 00 00 (Eq.............
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff8156a2de>] kmem_cache_alloc_trace+0x16e/0x230
[<ffffffff8162a479>] seq_open+0x79/0x1d0
[<ffffffffa0578510>] kcm_seq_open+0x0/0x30 [kcm]
[<ffffffff8162a479>] seq_open+0x79/0x1d0
[<ffffffff8162a8cf>] __seq_open_private+0x2f/0xa0
[<ffffffff81712548>] seq_open_net+0x38/0xa0
...
It is caused by a missing free in the ->release path. So fix it by
providing seq_release_net as the ->release method.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Fixes: cd6e111bf5 (kcm: Add statistics and proc interfaces)
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Tom Herbert <tom@herbertland.com>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
skb_splice_bits() returns int, kcm_splice_read() returns ssize_t,
both are signed.
We may need another patch to make them all ssize_t, but that
deserves a separated patch.
Fixes: 91687355b9 ("kcm: Splice support")
Reported-by: David Binderman <linuxdev.baldrick@gmail.com>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds receive timeout for message assembly on the attached TCP
sockets. The timeout is set when a new messages is started and the whole
message has not been received by TCP (not in the receive queue). If the
completely message is subsequently received the timer is cancelled, if the
timer expires the RX side is aborted.
The timeout value is taken from the socket timeout (SO_RCVTIMEO) that is
set on a TCP socket (i.e. set by get sockopt before attaching a TCP socket
to KCM.
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Message assembly is performed on the TCP socket. This is logically
equivalent of an application that performs a peek on the socket to find
out how much memory is needed for a receive buffer. The receive socket
buffer also provides the maximum message size which is checked.
The receive algorithm is something like:
1) Receive the first skbuf for a message (or skbufs if multiple are
needed to determine message length).
2) Check the message length against the number of bytes in the TCP
receive queue (tcp_inq()).
- If all the bytes of the message are in the queue (incluing the
skbuf received), then proceed with message assembly (it should
complete with the tcp_read_sock)
- Else, mark the psock with the number of bytes needed to
complete the message.
3) In TCP data ready function, if the psock indicates that we are
waiting for the rest of the bytes of a messages, check the number
of queued bytes against that.
- If there are still not enough bytes for the message, just
return
- Else, clear the waiting bytes and proceed to receive the
skbufs. The message should now be received in one
tcp_read_sock
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement kcm_sendpage. Set in sendpage to kcm_sendpage in both
dgram and seqpacket ops.
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement kcm_splice_read. This is supported only for seqpacket.
Add kcm_seqpacket_ops and set splice read to kcm_splice_read.
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds various counters for KCM. These include counters for
messages and bytes received or sent, as well as counters for number of
attached/unattached TCP sockets and other error or edge events.
The statistics are exposed via a proc interface. /proc/net/kcm provides
statistics per KCM socket and per psock (attached TCP sockets).
/proc/net/kcm_stats provides aggregate statistics.
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This module implements the Kernel Connection Multiplexor.
Kernel Connection Multiplexor (KCM) is a facility that provides a
message based interface over TCP for generic application protocols.
With KCM an application can efficiently send and receive application
protocol messages over TCP using datagram sockets.
For more information see the included Documentation/networking/kcm.txt
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tom Herbert