- bump version strings, by Simon Wunderlich
- update mailing list URL, by Sven Eckelmann
- fix typos and grammar in documentation, by Sven Eckelmann
- introduce a configurable per interface hop penalty,
by Linus Luessing
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Merge tag 'batadv-next-for-davem-20200630' of git://git.open-mesh.org/linux-merge
Simon Wunderlich says:
====================
This feature/cleanup patchset includes the following patches:
- bump version strings, by Simon Wunderlich
- update mailing list URL, by Sven Eckelmann
- fix typos and grammar in documentation, by Sven Eckelmann
- introduce a configurable per interface hop penalty,
by Linus Luessing
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
It is not very informative to know the DSA master device when a
subordinate network device fails to get its PHY setup. Provide the
device name and capitalize PHY while we are it.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
remove unused but set variable to avoid auto build test WARNING
Signed-off-by: Luo bin <luobin9@huawei.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- Zero out unused characters of FileName field to avoid a complaint from some fsck tool.
- Fix memory leak on error paths.
- Fix unnecessary VOL_DIRTY set when calling rmdir on non-empty directory.
- Call sync_filesystem() for read-only remount(Fix generic/452 test in xfstests)
- Add own fsync() to flush dirty metadata.
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Merge tag 'exfat-for-5.8-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat
Pull exfat fixes from Namjae Jeon:
- Zero out unused characters of FileName field to avoid a complaint
from some fsck tool.
- Fix memory leak on error paths.
- Fix unnecessary VOL_DIRTY set when calling rmdir on non-empty
directory.
- Call sync_filesystem() for read-only remount (Fix generic/452 test in
xfstests)
- Add own fsync() to flush dirty metadata.
* tag 'exfat-for-5.8-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
exfat: flush dirty metadata in fsync
exfat: move setting VOL_DIRTY over exfat_remove_entries()
exfat: call sync_filesystem for read-only remount
exfat: add missing brelse() calls on error paths
exfat: Set the unused characters of FileName field to the value 0000h
Jeff Kirsher says:
====================
1GbE Intel Wired LAN Driver Updates 2020-06-29
This series contains updates to only the igc driver.
Sasha added Energy Efficient Ethernet (EEE) support and Latency Tolerance
Reporting (LTR) support for the igc driver. Added Low Power Idle (LPI)
counters and cleaned up unused TCP segmentation counters. Removed
igc_power_down_link() and call igc_power_down_phy_copper_base()
directly. Removed unneeded copper media check.
Andre cleaned up timestamping by removing un-supported features and
duplicate code for i225. Fixed the timestamp check on the proper flag
instead of the skb for pending transmit timestamps. Refactored
igc_ptp_set_timestamp_mode() to simply the flow.
v2: Removed the log message in patch 1 as suggested by David Miller.
Note: The locking issue Jakub Kicinski saw in patch 5, currently
exists in the current net-next tree, so Andre will resolve the
locking issue in a follow-on patch.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Jason A. Donenfeld says:
====================
support AF_PACKET for layer 3 devices
Hans reported that packets injected by a correct-looking and trivial
libpcap-based program were not being accepted by wireguard. In
investigating that, I noticed that a few devices weren't properly
handling AF_PACKET-injected packets, and so this series introduces a bit
of shared infrastructure to support that.
The basic problem begins with socket(AF_PACKET, SOCK_RAW,
htons(ETH_P_ALL)) sockets. When sendto is called, AF_PACKET examines the
headers of the packet with this logic:
static void packet_parse_headers(struct sk_buff *skb, struct socket *sock)
{
if ((!skb->protocol || skb->protocol == htons(ETH_P_ALL)) &&
sock->type == SOCK_RAW) {
skb_reset_mac_header(skb);
skb->protocol = dev_parse_header_protocol(skb);
}
skb_probe_transport_header(skb);
}
The middle condition there triggers, and we jump to
dev_parse_header_protocol. Note that this is the only caller of
dev_parse_header_protocol in the kernel, and I assume it was designed
for this purpose:
static inline __be16 dev_parse_header_protocol(const struct sk_buff *skb)
{
const struct net_device *dev = skb->dev;
if (!dev->header_ops || !dev->header_ops->parse_protocol)
return 0;
return dev->header_ops->parse_protocol(skb);
}
Since AF_PACKET already knows which netdev the packet is going to, the
dev_parse_header_protocol function can see if that netdev has a way it
prefers to figure out the protocol from the header. This, again, is the
only use of parse_protocol in the kernel. At the moment, it's only used
with ethernet devices, via eth_header_parse_protocol. This makes sense,
as mostly people are used to AF_PACKET-injecting ethernet frames rather
than layer 3 frames. But with nothing in place for layer 3 netdevs, this
function winds up returning 0, and skb->protocol then is set to 0, and
then by the time it hits the netdev's ndo_start_xmit, the driver doesn't
know what to do with it.
This is a problem because drivers very much rely on skb->protocol being
correct, and routinely reject packets where it's incorrect. That's why
having this parsing happen for injected packets is quite important. In
wireguard, ipip, and ipip6, for example, packets from AF_PACKET are just
dropped entirely. For tun devices, it's sort of uglier, with the tun
"packet information" header being passed to userspace containing a bogus
protocol value. Some userspace programs are ill-equipped to deal with
that. (But of course, that doesn't happen with tap devices, which
benefit from the similar shared infrastructure for layer 2 netdevs,
further motiviating this patchset for layer 3 netdevs.)
This patchset addresses the issue by first adding a layer 3 header parse
function, much akin to the existing one for layer 2 packets, and then
adds a shared header_ops structure that, also much akin to the existing
one for layer 2 packets. Then it wires it up to a few immediate places
that stuck out as requiring it, and does a bit of cleanup.
This patchset seems like it's fixing real bugs, so it might be
appropriate for stable. But they're also very old bugs, so if you'd
rather not backport to stable, that'd make sense to me too.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The xfrm interface uses skb->protocol to determine packet type, and
bails out if it's not set. For AF_PACKET injection, we need to support
its call chain of:
packet_sendmsg -> packet_snd -> packet_parse_headers ->
dev_parse_header_protocol -> parse_protocol
Without a valid parse_protocol, this returns zero, and xfrmi rejects the
skb. So, this wires up the ip_tunnel handler for layer 3 packets for
that case.
Reported-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sit uses skb->protocol to determine packet type, and bails out if it's
not set. For AF_PACKET injection, we need to support its call chain of:
packet_sendmsg -> packet_snd -> packet_parse_headers ->
dev_parse_header_protocol -> parse_protocol
Without a valid parse_protocol, this returns zero, and sit rejects the
skb. So, this wires up the ip_tunnel handler for layer 3 packets for
that case.
Reported-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vti uses skb->protocol to determine packet type, and bails out if it's
not set. For AF_PACKET injection, we need to support its call chain of:
packet_sendmsg -> packet_snd -> packet_parse_headers ->
dev_parse_header_protocol -> parse_protocol
Without a valid parse_protocol, this returns zero, and vti rejects the
skb. So, this wires up the ip_tunnel handler for layer 3 packets for
that case.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The tun driver passes up skb->protocol to userspace in the form of PI headers.
For AF_PACKET injection, we need to support its call chain of:
packet_sendmsg -> packet_snd -> packet_parse_headers ->
dev_parse_header_protocol -> parse_protocol
Without a valid parse_protocol, this returns zero, and the tun driver
then gives userspace bogus values that it can't deal with.
Note that this isn't the case with tap, because tap already benefits
from the shared infrastructure for ethernet headers. But with tun,
there's nothing.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that wg_examine_packet_protocol has been added for general
consumption as ip_tunnel_parse_protocol, it's possible to remove
wg_examine_packet_protocol and simply use the new
ip_tunnel_parse_protocol function directly.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
WireGuard uses skb->protocol to determine packet type, and bails out if
it's not set or set to something it's not expecting. For AF_PACKET
injection, we need to support its call chain of:
packet_sendmsg -> packet_snd -> packet_parse_headers ->
dev_parse_header_protocol -> parse_protocol
Without a valid parse_protocol, this returns zero, and wireguard then
rejects the skb. So, this wires up the ip_tunnel handler for layer 3
packets for that case.
Reported-by: Hans Wippel <ndev@hwipl.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ipip uses skb->protocol to determine packet type, and bails out if it's
not set. For AF_PACKET injection, we need to support its call chain of:
packet_sendmsg -> packet_snd -> packet_parse_headers ->
dev_parse_header_protocol -> parse_protocol
Without a valid parse_protocol, this returns zero, and ipip rejects the
skb. So, this wires up the ip_tunnel handler for layer 3 packets for
that case.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some devices that take straight up layer 3 packets benefit from having a
shared header_ops so that AF_PACKET sockets can inject packets that are
recognized. This shared infrastructure will be used by other drivers
that currently can't inject packets using AF_PACKET. It also exposes the
parser function, as it is useful in standalone form too.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1) Fix hook iteration and default value for inode_copy_up_xattr
from KP Singh <kpsingh@google.com>
2) Fix the key_permission LSM hook function type
from Sami Tolvanen <samitolvanen@google.com>
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Merge tag 'fixes-v5.8-rc3-a' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem fixes from James Morris:
"Two simple fixes for v5.8:
- Fix hook iteration and default value for inode_copy_up_xattr
(KP Singh)
- Fix the key_permission LSM hook function type (Sami Tolvanen)"
* tag 'fixes-v5.8-rc3-a' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
security: Fix hook iteration and default value for inode_copy_up_xattr
security: fix the key_permission LSM hook function type
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Merge tag 'integrity-v5.8-fix-2' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity updates from Mimi Zohar:
"Include PCRs 8 & 9 in per TPM 2.0 bank boot_aggregate calculation.
Prior to Linux 5.8 the SHA1 "boot_aggregate" value was padded with 0's
and extended into the other TPM 2.0 banks.
Included in the Linux 5.8 open window, TPM 2.0 PCR bank specific
"boot_aggregate" values (PCRs 0 - 7) are calculated and extended into the TPM banks.
Distro releases are now shipping grub2 with TPM support, which extend
PCRs 8 & 9. I'd like for PCRs 8 & 9 to be included in the new
"boot_aggregate" calculations.
For backwards compatibility, if the hash is SHA1, these new PCRs are
not included in the boot aggregate"
* tag 'integrity-v5.8-fix-2' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
ima: extend boot_aggregate with kernel measurements
Instead, expose the key via the input framework, as SW_MACHINE_COVER
The chip-detect GPIO is actually detecting if the cover is closed.
Technically it's possible to use the SD card with open cover. The
only downside is risk of battery falling out and user being able
to physically remove the card.
The behaviour of SD card not being available when the device is
open is unexpected and creates more problems than it solves. There
is a high chance, that more people accidentally break their rootfs
by opening the case without physically removing the card.
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Merlijn Wajer <merlijn@wizzup.org>
Link: https://lore.kernel.org/r/20200612125402.18393-3-merlijn@wizzup.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This event code represents the state of a removable cover of a device.
Value 0 means that the cover is open or removed, value 1 means that the
cover is closed.
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Merlijn Wajer <merlijn@wizzup.org>
Link: https://lore.kernel.org/r/20200612125402.18393-2-merlijn@wizzup.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
There is a statement that is indented one level too deeply, fix it
by removing a tab.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move .nr_active update and request assignment into blk_mq_get_driver_tag(),
all are good to do during getting driver tag.
Meantime blk-flush related code is simplified and flush request needn't
to update the request table manually any more.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It is used by blk-mq.c only, so move it to the source file.
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
blk_mq_get_driver_tag() is only used by blk-mq.c and is supposed to
stay in blk-mq.c, so move it and preparing for cleanup code of
get/put driver tag.
Meantime hctx_may_queue() is moved to header file and it is fine
since it is defined as inline always.
No functional change.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
RAPL on SPR behaves similar to Haswell server, except that SPR uses
a fixed energy unit (1 Joule) for the PSYS RAPL domain.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since 5.7, we've been using task_work to trigger async running of
requests in the context of the original task. This generally works
great, but there's a case where if the task is currently blocked
in the kernel waiting on a condition to become true, it won't process
task_work. Even though the task is woken, it just checks whatever
condition it's waiting on, and goes back to sleep if it's still false.
This is a problem if that very condition only becomes true when that
task_work is run. An example of that is the task registering an eventfd
with io_uring, and it's now blocked waiting on an eventfd read. That
read could depend on a completion event, and that completion event
won't get trigged until task_work has been run.
Use the TWA_SIGNAL notification for task_work, so that we ensure that
the task always runs the work when queued.
Cc: stable@vger.kernel.org # v5.7
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Rearrange the allocation of the mm_struct registration to avoid
allocating underneath the i915->mm_lock, so that we avoid tainting the
lock (and in turn many other locks that may be held as i915->mm_lock is
taken, and those locks we may want on the free [shrinker] paths). In
doing so, we convert the lookup to be RCU protected by courtesy of
converting the free-worker to be an rcu_work.
v2: Remember to use hash_rcu variants to protect the list iteration from
concurrent add/del.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200619194038.5088-1-chris@chris-wilson.co.uk
Up until now, if an event is interrupted while it is recorded by an
interrupt, and that interrupt records events, the time of those events will
all be the same. This is because events only record the delta of the time
since the previous event (or beginning of a page), and to handle updating
the time keeping for that of nested events is extremely racy. After years of
thinking about this and several failed attempts, I finally have a solution
to solve this puzzle.
The problem is that you need to atomically calculate the delta and then
update the time stamp you made the delta from, as well as then record it
into the buffer, all this while at any time an interrupt can come in and
do the same thing. This is easy to solve with heavy weight atomics, but that
would be detrimental to the performance of the ring buffer. The current
state of affairs sacrificed the time deltas for nested events for
performance.
The reason for previous failed attempts at solving this puzzle was because I
was trying to completely avoid slow atomic operations like cmpxchg. I final
came to the conclusion to always avoid cmpxchg is not possible, which is why
those previous attempts always failed. But it is possible to pick one path
(the most common case) and avoid cmpxchg in that path, which is the "fast
path". The most common case is that an event will not be interrupted and
have other events added into it. An event can detect if it has
interrupted another event, and for these cases we can make it the slow
path and use the heavy operations like cmpxchg.
One more player was added to the game that made this possible, and that is
the "absolute timestamp" (by Tom Zanussi) that allows us to inject a full 59
bit time stamp. (Of course this breaks if a machine is running for more than
18 years without a reboot!).
There's barrier() placements around for being paranoid, even when they
are not needed because of other atomic functions near by. But those
should not hurt, as if they are not needed, they basically become a nop.
Note, this also makes the race window much smaller, which means there
are less slow paths to slow down the performance.
The basic idea is that there's two main paths taken.
1) Not being interrupted between time stamps and reserving buffer space.
In this case, the time stamps taken are true to the location in the
buffer.
2) Was interrupted by another path between taking time stamps and reserving
buffer space.
The objective is to know what the delta is from the last reserved location
in the buffer.
As it is possible to detect if an event is interrupting another event before
reserving data, space is added to the length to be reserved to inject a full
time stamp along with the event being reserved.
When an event is not interrupted, the write stamp is always the time of the
last event written to the buffer.
In path 1, there's two sub paths we care about:
a) The event did not interrupt another event.
b) The event interrupted another event.
In case a, as the write stamp was read and known to be correct, the delta
between the current time stamp and the write stamp is the delta between the
current event and the previously recorded event.
In case b, extra space was reserved to just put the full time stamp into the
buffer. Which is done, as stated, in this path the time stamp taken is known
to match the location in the buffer.
In path 2, there's also two sub paths we care about:
a) The event was not interrupted by another event since it reserved space
on the buffer and re-reading the write stamp.
b) The event was interrupted by another event.
In case a, the write stamp is that of the last event that interrupted this
event between taking the time stamps and reserving. As no event came in
after re-reading the write stamp, that event is known to be the time of the
event directly before this event and the delta can be the new time stamp and
the write stamp.
In case b, one or more events came in between reserving the event and
re-reading he write stamp. Since this event's buffer reservation is between
other events at this path, there's no way to know what the delta is. But
because an event interrupted this event after it started, its fine to just
give a zero delta, and take the same time stamp as the events that happened
within the event being recorded.
Here's the implementation of the design of this solution:
All this is per cpu, and only needs to worry about nested events (not
parallel events).
The players:
write_tail: The index in the buffer where new events can be written to.
It is incremented via local_add() to reserve space for a new event.
before_stamp: A time stamp set by all events before reserving space.
write_stamp: A time stamp updated by events after it has successfully
reserved space.
/* Save the current position of write */
[A] w = local_read(write_tail);
barrier();
/* Read both before and write stamps before touching anything */
before = local_read(before_stamp);
after = local_read(write_stamp);
barrier();
/*
* If before and after are the same, then this event is not
* interrupting a time update. If it is, then reserve space for adding
* a full time stamp (this can turn into a time extend which is
* just an extended time delta but fill up the extra space).
*/
if (after != before)
abs = true;
ts = clock();
/* Now update the before_stamp (everyone does this!) */
[B] local_set(before_stamp, ts);
/* Now reserve space on the buffer */
[C] write = local_add_return(len, write_tail);
/* Set tail to be were this event's data is */
tail = write - len;
if (w == tail) {
/* Nothing interrupted this between A and C */
[D] local_set(write_stamp, ts);
barrier();
[E] save_before = local_read(before_stamp);
if (!abs) {
/* This did not interrupt a time update */
delta = ts - after;
} else {
delta = ts; /* The full time stamp will be in use */
}
if (ts != save_before) {
/* slow path - Was interrupted between C and E */
/* The update to write_stamp could have overwritten the update to
* it by the interrupting event, but before and after should be
* the same for all completed top events */
after = local_read(write_stamp);
if (save_before > after)
local_cmpxchg(write_stamp, after, save_before);
}
} else {
/* slow path - Interrupted between A and C */
after = local_read(write_stamp);
temp_ts = clock();
barrier();
[F] if (write == local_read(write_tail) && after < temp_ts) {
/* This was not interrupted since C and F
* The last write_stamp is still valid for the previous event
* in the buffer. */
delta = temp_ts - after;
/* OK to keep this new time stamp */
ts = temp_ts;
} else {
/* Interrupted between C and F
* Well, there's no use to try to know what the time stamp
* is for the previous event. Just set delta to zero and
* be the same time as that event that interrupted us before
* the reservation of the buffer. */
delta = 0;
}
/* No need to use full timestamps here */
abs = 0;
}
Link: https://lkml.kernel.org/r/20200625094454.732790f7@oasis.local.home
Link: https://lore.kernel.org/r/20200627010041.517736087@goodmis.org
Link: http://lkml.kernel.org/r/20200629025258.957440797@goodmis.org
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If a process has the trace_pipe open on a trace_array, the current tracer
for that trace array should not be changed. This was original enforced by a
global lock, but when instances were introduced, it was moved to the
current_trace. But this structure is shared by all instances, and a
trace_pipe is for a single instance. There's no reason that a process that
has trace_pipe open on one instance should prevent another instance from
changing its current tracer. Move the reference counter to the trace_array
instead.
This is marked as "Fixes" but is more of a clean up than a true fix.
Backport if you want, but its not critical.
Fixes: cf6ab6d914 ("tracing: Add ref count to tracer for when they are being read by pipe")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
After the previous cleanup, DEFINE_EVENT_PRINT's definition has no
relationship with DEFINE_EVENT. So After we re-define DEFINE_EVENT, it
is not necessary to define DEFINE_EVENT_PRINT to be empty again.
Link: http://lkml.kernel.org/r/20200612092844.56107-5-richard.weiyang@linux.alibaba.com
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Current definition define DEFINE_EVENT_PRINT to be DEFINE_EVENT.
Actually, at this point DEFINE_EVENT is already an empty macro. Let's
cut the relationship between DEFINE_EVENT_PRINT and DEFINE_EVENT.
Link: http://lkml.kernel.org/r/20200612092844.56107-4-richard.weiyang@linux.alibaba.com
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The definition of DEFINE_EVENT_PRINT is not changed after previous one,
so not necessary to re-define is as the same form.
Link: http://lkml.kernel.org/r/20200612092844.56107-3-richard.weiyang@linux.alibaba.com
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
After un-define DEFINE_EVENT in Stage 2, DEFINE_EVENT is not defined to a
specific form. It is not necessary to un-define it again.
Let's skip this.
Link: http://lkml.kernel.org/r/20200612092844.56107-2-richard.weiyang@linux.alibaba.com
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
So that the target task will exit the wait_event_interruptible-like
loop and call task_work_run() asap.
The patch turns "bool notify" into 0,TWA_RESUME,TWA_SIGNAL enum, the
new TWA_SIGNAL flag implies signal_wake_up(). However, it needs to
avoid the race with recalc_sigpending(), so the patch also adds the
new JOBCTL_TASK_WORK bit included in JOBCTL_PENDING_MASK.
TODO: once this patch is merged we need to change all current users
of task_work_add(notify = true) to use TWA_RESUME.
Cc: stable@vger.kernel.org # v5.7
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The lkml.org, spinics.net, and gmane.org archives are not very reliable
and, in some cases, not even easily accessible. Replace links to them with
links to lore.kernel.org, the archives hosted by kernel.org.
I found the gmane items via the Wayback Machine archive at
https://web.archive.org/.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Replace http:// links with https:// links. This reduces the likelihood of
man-in-the-middle attacks when developers open these links.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
[bhelgaas: also update samsung.com links, drop sourceforge link]
Link: https://lore.kernel.org/r/20200627103050.71712-1-grandmaster@al2klimov.de
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Iterating over BPF links attached to network namespace in pre_exit hook is
not safe, even if there is just one. Once link gets auto-detached, that is
its back-pointer to net object is set to NULL, the link can be released and
freed without waiting on netns_bpf_mutex, effectively causing the list
element we are operating on to be freed.
This leads to use-after-free when trying to access the next element on the
list, as reported by KASAN. Bug can be triggered by destroying a network
namespace, while also releasing a link attached to this network namespace.
| ==================================================================
| BUG: KASAN: use-after-free in netns_bpf_pernet_pre_exit+0xd9/0x130
| Read of size 8 at addr ffff888119e0d778 by task kworker/u8:2/177
|
| CPU: 3 PID: 177 Comm: kworker/u8:2 Not tainted 5.8.0-rc1-00197-ga0c04c9d1008-dirty #776
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014
| Workqueue: netns cleanup_net
| Call Trace:
| dump_stack+0x9e/0xe0
| print_address_description.constprop.0+0x3a/0x60
| ? netns_bpf_pernet_pre_exit+0xd9/0x130
| kasan_report.cold+0x1f/0x40
| ? netns_bpf_pernet_pre_exit+0xd9/0x130
| netns_bpf_pernet_pre_exit+0xd9/0x130
| cleanup_net+0x30b/0x5b0
| ? unregister_pernet_device+0x50/0x50
| ? rcu_read_lock_bh_held+0xb0/0xb0
| ? _raw_spin_unlock_irq+0x24/0x50
| process_one_work+0x4d1/0xa10
| ? lock_release+0x3e0/0x3e0
| ? pwq_dec_nr_in_flight+0x110/0x110
| ? rwlock_bug.part.0+0x60/0x60
| worker_thread+0x7a/0x5c0
| ? process_one_work+0xa10/0xa10
| kthread+0x1e3/0x240
| ? kthread_create_on_node+0xd0/0xd0
| ret_from_fork+0x1f/0x30
|
| Allocated by task 280:
| save_stack+0x1b/0x40
| __kasan_kmalloc.constprop.0+0xc2/0xd0
| netns_bpf_link_create+0xfe/0x650
| __do_sys_bpf+0x153a/0x2a50
| do_syscall_64+0x59/0x300
| entry_SYSCALL_64_after_hwframe+0x44/0xa9
|
| Freed by task 198:
| save_stack+0x1b/0x40
| __kasan_slab_free+0x12f/0x180
| kfree+0xed/0x350
| process_one_work+0x4d1/0xa10
| worker_thread+0x7a/0x5c0
| kthread+0x1e3/0x240
| ret_from_fork+0x1f/0x30
|
| The buggy address belongs to the object at ffff888119e0d700
| which belongs to the cache kmalloc-192 of size 192
| The buggy address is located 120 bytes inside of
| 192-byte region [ffff888119e0d700, ffff888119e0d7c0)
| The buggy address belongs to the page:
| page:ffffea0004678340 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0
| flags: 0x2fffe0000000200(slab)
| raw: 02fffe0000000200 ffffea00045ba8c0 0000000600000006 ffff88811a80ea80
| raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
| page dumped because: kasan: bad access detected
|
| Memory state around the buggy address:
| ffff888119e0d600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
| ffff888119e0d680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
| >ffff888119e0d700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
| ^
| ffff888119e0d780: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
| ffff888119e0d800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
| ==================================================================
Remove the "fast-path" for releasing a link that got auto-detached by a
dying network namespace to fix it. This way as long as link is on the list
and netns_bpf mutex is held, we have a guarantee that link memory can be
accessed.
An alternative way to fix this issue would be to safely iterate over the
list of links and ensure there is no access to link object after detaching
it. But, at the moment, optimizing synchronization overhead on link release
without a workload in mind seems like an overkill.
Fixes: ab53cad90e ("bpf, netns: Keep a list of attached bpf_link's")
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200630164541.1329993-1-jakub@cloudflare.com
A few small driver specific fixes, nothing particularly dramatic.
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Merge tag 'asoc-fix-v5.8-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Fixes for v5.8
A few small driver specific fixes, nothing particularly dramatic.
Commit f0bd62b640 ("ALSA: usb-audio: Improve frames size computation")
introduced a regression for devices which have playback endpoints with
bInterval > 1. Fix this by taking ep->datainterval into account.
Note that frame and fps are actually mean packet and packets per second
in the code introduces by the mentioned commit. This will be fixed in a
follow-up patch.
Fixes: f0bd62b640 ("ALSA: usb-audio: Improve frames size computation")
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=208353
Signed-off-by: Alexander Tsoy <alexander@tsoy.me>
Link: https://lore.kernel.org/r/20200629025934.154288-1-alexander@tsoy.me
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Lorenz Bauer says:
====================
Both sockmap and flow_dissector ingnore various arguments passed to
BPF_PROG_ATTACH and BPF_PROG_DETACH. We can fix the attach case by
checking that the unused arguments are zero. I considered requiring
target_fd to be -1 instead of 0, but this leads to a lot of churn
in selftests. There is also precedent in that bpf_iter already
expects 0 for a similar field. I think that we can come up with a
work around for fd 0 should we need to in the future.
The detach case is more problematic: both cgroups and lirc2 verify
that attach_bpf_fd matches the currently attached program. This
way you need access to the program fd to be able to remove it.
Neither sockmap nor flow_dissector do this. flow_dissector even
has a check for CAP_NET_ADMIN because of this. The patch set
addresses this by implementing the desired behaviour.
There is a possibility for user space breakage: any callers that
don't provide the correct fd will fail with ENOENT. For sockmap
the risk is low: even the selftests assume that sockmap works
the way I described. For flow_dissector the story is less
straightforward, and the selftests use a variety of arguments.
I've includes fixes tags for the oldest commits that allow an easy
backport, however the behaviour dates back to when sockmap and
flow_dissector were introduced. What is the best way to handle these?
This set is based on top of Jakub's work "bpf, netns: Prepare
for multi-prog attachment" available at
https://lore.kernel.org/bpf/87k0zwmhtb.fsf@cloudflare.com/T/
Since v1:
- Adjust selftests
- Implement detach behaviour
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Calling bpf_prog_detach is incorrect, since it takes target_fd as
its argument. The intention here is to pass it as attach_bpf_fd,
so use bpf_prog_detach2 and pass zero for target_fd.
Fixes: 06716e04a0 ("selftests/bpf: Extend test_flow_dissector to cover link creation")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-7-lmb@cloudflare.com
Pass 0 as target_fd when attaching and detaching flow dissector.
Additionally, pass the expected program when detaching.
Fixes: 1f043f87bb ("selftests/bpf: Add tests for attaching bpf_link to netns")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-6-lmb@cloudflare.com
The sockmap code currently ignores the value of attach_bpf_fd when
detaching a program. This is contrary to the usual behaviour of
checking that attach_bpf_fd represents the currently attached
program.
Ensure that attach_bpf_fd is indeed the currently attached
program. It turns out that all sockmap selftests already do this,
which indicates that this is unlikely to cause breakage.
Fixes: 604326b41a ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-5-lmb@cloudflare.com
Using BPF_PROG_ATTACH on a sockmap program currently understands no
flags or replace_bpf_fd, but accepts any value. Return EINVAL instead.
Fixes: 604326b41a ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-4-lmb@cloudflare.com
Using BPF_PROG_DETACH on a flow dissector program supports neither
attach_flags nor attach_bpf_fd. Yet no value is enforced for them.
Enforce that attach_flags are zero, and require the current program
to be passed via attach_bpf_fd. This allows us to remove the check
for CAP_SYS_ADMIN, since userspace can now no longer remove
arbitrary flow dissector programs.
Fixes: b27f7bb590 ("flow_dissector: Move out netns_bpf prog callbacks")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-3-lmb@cloudflare.com
Using BPF_PROG_ATTACH on a flow dissector program supports neither
target_fd, attach_flags or replace_bpf_fd but accepts any value.
Enforce that all of them are zero. This is fine for replace_bpf_fd
since its presence is indicated by BPF_F_REPLACE. It's more
problematic for target_fd, since zero is a valid fd. Should we
want to use the flag later on we'd have to add an exception for
fd 0. The alternative is to force a value like -1. This requires
more changes to tests. There is also precedent for using 0,
since bpf_iter uses this for target_fd as well.
Fixes: b27f7bb590 ("flow_dissector: Move out netns_bpf prog callbacks")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-2-lmb@cloudflare.com
Jakub Sitnicki says:
====================
This patch set prepares ground for link-based multi-prog attachment for
future netns attach types, with BPF_SK_LOOKUP attach type in mind [0].
Two changes are needed in order to attach and run a series of BPF programs:
1) an bpf_prog_array of programs to run (patch #2), and
2) a list of attached links to keep track of attachments (patch #3).
Nothing changes for BPF flow_dissector. Just as before only one program can
be attached to netns.
In v3 I've simplified patch #2 that introduces bpf_prog_array to take
advantage of the fact that it will hold at most one program for now.
In particular, I'm no longer using bpf_prog_array_copy. It turned out to be
less suitable for link operations than I thought as it fails to append the
same BPF program.
bpf_prog_array_replace_item is also gone, because we know we always want to
replace the first element in prog_array.
Naturally the code that handles bpf_prog_array will need change once
more when there is a program type that allows multi-prog attachment. But I
feel it will be better to do it gradually and present it together with
tests that actually exercise multi-prog code paths.
[0] https://lore.kernel.org/bpf/20200511185218.1422406-1-jakub@cloudflare.com/
v2 -> v3:
- Don't check if run_array is null in link update callback. (Martin)
- Allow updating the link with the same BPF program. (Andrii)
- Add patch #4 with a test for the above case.
- Kill bpf_prog_array_replace_item. Access the run_array directly.
- Switch from bpf_prog_array_copy() to bpf_prog_array_alloc(1, ...).
- Replace rcu_deref_protected & RCU_INIT_POINTER with rcu_replace_pointer.
- Drop Andrii's Ack from patch #2. Code changed.
v1 -> v2:
- Show with a (void) cast that bpf_prog_array_replace_item() return value
is ignored on purpose. (Andrii)
- Explain why bpf-cgroup cannot replace programs in bpf_prog_array based
on bpf_prog pointer comparison in patch #2 description. (Andrii)
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This case, while not particularly useful, is worth covering because we
expect the operation to succeed as opposed when re-attaching the same
program directly with PROG_ATTACH.
While at it, update the tests summary that fell out of sync when tests
extended to cover links.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200625141357.910330-5-jakub@cloudflare.com
To support multi-prog link-based attachments for new netns attach types, we
need to keep track of more than one bpf_link per attach type. Hence,
convert net->bpf.links into a list, that currently can be either empty or
have just one item.
Instead of reusing bpf_prog_list from bpf-cgroup, we link together
bpf_netns_link's themselves. This makes list management simpler as we don't
have to allocate, initialize, and later release list elements. We can do
this because multi-prog attachment will be available only for bpf_link, and
we don't need to build a list of programs attached directly and indirectly
via links.
No functional changes intended.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200625141357.910330-4-jakub@cloudflare.com
Prepare for having multi-prog attachments for new netns attach types by
storing programs to run in a bpf_prog_array, which is well suited for
iterating over programs and running them in sequence.
After this change bpf(PROG_QUERY) may block to allocate memory in
bpf_prog_array_copy_to_user() for collected program IDs. This forces a
change in how we protect access to the attached program in the query
callback. Because bpf_prog_array_copy_to_user() can sleep, we switch from
an RCU read lock to holding a mutex that serializes updaters.
Because we allow only one BPF flow_dissector program to be attached to
netns at all times, the bpf_prog_array pointed by net->bpf.run_array is
always either detached (null) or one element long.
No functional changes intended.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200625141357.910330-3-jakub@cloudflare.com
