zhangyi (F) [Wed, 6 Nov 2019 09:43:52 +0000 (17:43 +0800)]
fs/dcache: move security_d_instantiate() behind attaching dentry to inode
During backport 1e2e547a93a "do d_instantiate/unlock_new_inode
combinations safely", there was a error instantiating sequence of
attaching dentry to inode and calling security_d_instantiate().
Before commit ce23e640133 "->getxattr(): pass dentry and inode as
separate arguments" and b96809173e9 "security_d_instantiate(): move to
the point prior to attaching dentry to inode", security_d_instantiate()
should be called beind __d_instantiate(), otherwise it will trigger
below problem when CONFIG_SECURITY_SMACK on ext4 was enabled because
d_inode(dentry) used by ->getxattr() is NULL before __d_instantiate()
instantiate inode.
It's possible to hit the WARN_ON_ONCE(page_mapped(page)) in
remove_stable_node() when it races with __mmput() and squeezes in
between ksm_exit() and exit_mmap().
WARNING: CPU: 0 PID: 3295 at mm/ksm.c:888 remove_stable_node+0x10c/0x150
The workqueue only exists for the primary PF. For other functions
we hit a WARN_ON in kernel/workqueue.c.
Fixes: 7c236c43b838 ("sfc: Add support for IEEE-1588 PTP") Signed-off-by: Martin Habets <mhabets@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
when configuring act_pedit rules, the number of keys is validated only on
addition of a new entry. This is not sufficient to avoid hitting a WARN()
in the traffic path: for example, it is possible to replace a valid entry
with a new one having 0 extended keys, thus causing splats in dmesg like:
Fix this moving the check on 'nkeys' earlier in tcf_pedit_init(), so that
attempts to install rules having 0 keys are always rejected with -EINVAL.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16:
- Drop change in tcf_pedit_keys_ex_parse()
- netlink doesn't support error messages
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This happens because buffers for the in_vq are allocated when the port is
added but are not released when the port is unplugged.
They are only released when virtconsole is removed (see a7a69ec0d8e4)
To avoid the problem and to be symmetric, we could allocate all the buffers
in init_vqs() as they are released in remove_vqs(), but it sounds like
a waste of memory.
Rather than that, this patch changes add_port() logic to ignore ENOSPC
error in fill_queue(), which means queue has already been filled.
Fixes: a7a69ec0d8e4 ("virtio_console: free buffers after reset") Cc: mst@redhat.com Signed-off-by: Laurent Vivier <lvivier@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
An exiting task might belong to an offline cgroup. In this case an
attempt to grab a cgroup reference from the task can end up with an
infinite loop in hugetlb_cgroup_charge_cgroup(), because neither the
cgroup will become online, neither the task will be migrated to a live
cgroup.
Fix this by switching over to css_tryget(). As css_tryget_online()
can't guarantee that the cgroup won't go offline, in most cases the
check doesn't make sense. In this particular case users of
hugetlb_cgroup_charge_cgroup() are not affected by this change.
A similar problem is described by commit 18fa84a2db0e ("cgroup: Use
css_tryget() instead of css_tryget_online() in task_get_css()").
Link: http://lkml.kernel.org/r/20191106225131.3543616-2-guro@fb.com Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Shakeel Butt <shakeelb@google.com> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
We've encountered a rcu stall in get_mem_cgroup_from_mm():
rcu: INFO: rcu_sched self-detected stall on CPU
rcu: 33-....: (21000 ticks this GP) idle=6c6/1/0x4000000000000002 softirq=35441/35441 fqs=5017
(t=21031 jiffies g=324821 q=95837) NMI backtrace for cpu 33
<...>
RIP: 0010:get_mem_cgroup_from_mm+0x2f/0x90
<...>
__memcg_kmem_charge+0x55/0x140
__alloc_pages_nodemask+0x267/0x320
pipe_write+0x1ad/0x400
new_sync_write+0x127/0x1c0
__kernel_write+0x4f/0xf0
dump_emit+0x91/0xc0
writenote+0xa0/0xc0
elf_core_dump+0x11af/0x1430
do_coredump+0xc65/0xee0
get_signal+0x132/0x7c0
do_signal+0x36/0x640
exit_to_usermode_loop+0x61/0xd0
do_syscall_64+0xd4/0x100
entry_SYSCALL_64_after_hwframe+0x44/0xa9
The problem is caused by an exiting task which is associated with an
offline memcg. We're iterating over and over in the do {} while
(!css_tryget_online()) loop, but obviously the memcg won't become online
and the exiting task won't be migrated to a live memcg.
Let's fix it by switching from css_tryget_online() to css_tryget().
As css_tryget_online() cannot guarantee that the memcg won't go offline,
the check is usually useless, except some rare cases when for example it
determines if something should be presented to a user.
A similar problem is described by commit 18fa84a2db0e ("cgroup: Use
css_tryget() instead of css_tryget_online() in task_get_css()").
Johannes:
: The bug aside, it doesn't matter whether the cgroup is online for the
: callers. It used to matter when offlining needed to evacuate all charges
: from the memcg, and so needed to prevent new ones from showing up, but we
: don't care now.
Link: http://lkml.kernel.org/r/20191106225131.3543616-1-guro@fb.com Signed-off-by: Roman Gushchin <guro@fb.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Shakeel Butt <shakeeb@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutn <mkoutny@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
While output urb's snd_complete_urb() is executing, calling
prepare_outbound_urb() may cause endpoint stopped before
prepare_outbound_urb() returns and result in next urb submitted
to stopped endpoint. usb-audio driver cannot re-use it afterwards as
the urb is still hold by usb stack.
This change checks EP_FLAG_RUNNING flag after prepare_outbound_urb() again
to let snd_complete_urb() know the endpoint already stopped and does not
submit next urb. Below kind of error will be fixed:
[ 213.153103] usb 1-2: timeout: still 1 active urbs on EP #1
[ 213.164121] usb 1-2: cannot submit urb 0, error -16: unknown error
Some Coffee Lake platforms have a skewed HPET timer once the SoCs entered
PC10, which in consequence marks TSC as unstable because HPET is used as
watchdog clocksource for TSC.
Harry Pan tried to work around it in the clocksource watchdog code [1]
thereby creating a circular dependency between HPET and TSC. This also
ignores the fact, that HPET is not only unsuitable as watchdog clocksource
on these systems, it becomes unusable in general.
We need to get the underlying dentry of parent; sure, absent the races
it is the parent of underlying dentry, but there's nothing to prevent
losing a timeslice to preemtion in the middle of evaluation of
lower_dentry->d_parent->d_inode, having another process move lower_dentry
around and have its (ex)parent not pinned anymore and freed on memory
pressure. Then we regain CPU and try to fetch ->d_inode from memory
that is freed by that point.
dentry->d_parent *is* stable here - it's an argument of ->lookup() and
we are guaranteed that it won't be moved anywhere until we feed it
to d_add/d_splice_alias. So we safely go that way to get to its
underlying dentry.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[bwh: Backported to 3.16:
- Open-code d_inode()
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
lower_dentry can't go from positive to negative (we have it pinned),
but it *can* go from negative to positive. So fetching ->d_inode
into a local variable, doing a blocking allocation, checking that
now ->d_inode is non-NULL and feeding the value we'd fetched
earlier to a function that won't accept NULL is not a good idea.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[bwh: Backported to 3.16:
- Use ACCESS_ONCE() instead of READ_ONCE()
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
A check of the return value from get_cur_mix_raw() is missing at the
resolution test code in get_min_max_with_quirks(), which may leave the
variable untouched, leading to a random uninitialized value, as
detected by syzkaller fuzzer.
Add the missing return error check for fixing that.
There are two callers of this function and they both unlock the mutex so
this ends up being a double unlock.
Fixes: 44ed167da748 ("drbd: rcu_read_lock() and rcu_dereference() for tconn->net_conf") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
In the current code, we use the atomic_cmpxchg() to serialize the output
of the dump_stack(), but this implementation suffers the thundering herd
problem. We have observed such kind of livelock on a Marvell cn96xx
board(24 cpus) when heavily using the dump_stack() in a kprobe handler.
Actually we can let the competitors to wait for the releasing of the
lock before jumping to atomic_cmpxchg(). This will definitely mitigate
the thundering herd problem. Thanks Linus for the suggestion.
[akpm@linux-foundation.org: fix comment] Link: http://lkml.kernel.org/r/20191030031637.6025-1-haokexin@gmail.com Fixes: b58d977432c8 ("dump_stack: serialize the output from dump_stack()") Signed-off-by: Kevin Hao <haokexin@gmail.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
/proc/pagetypeinfo is a debugging tool to examine internal page
allocator state wrt to fragmentation. It is not very useful for any
other use so normal users really do not need to read this file.
Waiman Long has noticed that reading this file can have negative side
effects because zone->lock is necessary for gathering data and that a)
interferes with the page allocator and its users and b) can lead to hard
lockups on large machines which have very long free_list.
Reduce both issues by simply not exporting the file to regular users.
Link: http://lkml.kernel.org/r/20191025072610.18526-2-mhocko@kernel.org Fixes: 467c996c1e19 ("Print out statistics in relation to fragmentation avoidance to /proc/pagetypeinfo") Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Waiman Long <longman@redhat.com> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Waiman Long <longman@redhat.com> Acked-by: Rafael Aquini <aquini@redhat.com> Acked-by: David Rientjes <rientjes@google.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: David Hildenbrand <david@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Roman Gushchin <guro@fb.com> Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Cc: Jann Horn <jannh@google.com> Cc: Song Liu <songliubraving@fb.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The final sort might get confused when the comparison is done over
bigger numbers than int like for -s time.
Check the following report for longer workloads:
$ perf report -s time -F time,overhead --stdio
Fix hist_entry__sort() to properly return int64_t and not possible cut
int.
Fixes: 043ca389a318 ("perf tools: Use hpp formats to sort final output") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Reviewed-by: Andi Kleen <ak@linux.intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/20191104232711.16055-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When the status register is read without the status IRQ pending, the
chip may not raise the interrupt line for an upcoming status interrupt
and the driver may miss a status interrupt.
It is critical that the BUSOFF status interrupt is forwarded to the
higher layers, since no more interrupts will follow without
intervention.
Thanks to Wolfgang and Joe for bringing up the first idea.
Signed-off-by: Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be> Cc: Wolfgang Grandegger <wg@grandegger.com> Cc: Joe Burmeister <joe.burmeister@devtank.co.uk> Fixes: fa39b54ccf28 ("can: c_can: Get rid of pointless interrupts") Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When decoding a buffer received from PCAN-USB, the first timestamp read in
a packet is a 16-bit coded time base, and the next ones are an 8-bit
offset to this base, regardless of the type of packet read.
This patch corrects a potential loss of synchronization by using a
timestamp index read from the buffer, rather than an index of received
data packets, to determine on the sizeof the timestamp to be read from the
packet being decoded.
Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com> Fixes: 46be265d3388 ("can: usb: PEAK-System Technik PCAN-USB specific part") Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The driver was accessing its driver data after having freed it.
Fixes: 0024d8ad1639 ("can: usb_8dev: Add support for USB2CAN interface from 8 devices") Cc: Bernd Krumboeck <b.krumboeck@gmail.com> Cc: Wolfgang Grandegger <wg@grandegger.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Invoking the following commands on a 32-bit architecture with strict
alignment requirements (such as an ARMv7-based Raspberry Pi) results
in an alignment exception:
# nft add table ip test-ip4
# nft add chain ip test-ip4 output { type filter hook output priority 0; }
# nft add rule ip test-ip4 output quota 1025 bytes
The reason is that nft_quota_do_init() calls atomic64_set() on an
atomic64_t which is only aligned to 32-bit, not 64-bit, because it
succeeds struct nft_expr in memory which only contains a 32-bit pointer.
Fix by aligning the nft_expr private data to 64-bit.
Fixes: 96518518cc41 ("netfilter: add nftables") Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The copy_to_user() function returns the number of bytes remaining to be
copied. In this code, that positive return is checked at the end of the
function and we return zero/success. What we should do instead is
return -EFAULT.
Fixes: a7b4f989a629 ("netfilter: ipset: IP set core support") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
For some reason I missed the case of DCCP passive
flows in my previous patch.
Fixes: a904a0693c18 ("inet: stop leaking jiffies on the wire") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Thiemo Nagel <tnagel@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
For Focusrite Saffire Pro i/o, the lowest 8 bits of register represents
configured source of sampling clock. The next lowest 8 bits represents
whether the configured source is actually detected or not just after
the register is changed for the source.
Current implementation evaluates whole the register to detect configured
source. This results in failure due to the next lowest 8 bits when the
source is connected in advance.
This commit fixes the bug.
Fixes: 25784ec2d034 ("ALSA: bebob: Add support for Focusrite Saffire/SaffirePro series") Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Link: https://lore.kernel.org/r/20191102150920.20367-1-o-takashi@sakamocchi.jp Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Historically linux tried to stick to RFC 791, 1122, 2003
for IPv4 ID field generation.
RFC 6864 made clear that no matter how hard we try,
we can not ensure unicity of IP ID within maximum
lifetime for all datagrams with a given source
address/destination address/protocol tuple.
Linux uses a per socket inet generator (inet_id), initialized
at connection startup with a XOR of 'jiffies' and other
fields that appear clear on the wire.
Thiemo Nagel pointed that this strategy is a privacy
concern as this provides 16 bits of entropy to fingerprint
devices.
Let's switch to a random starting point, this is just as
good as far as RFC 6864 is concerned and does not leak
anything critical.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Thiemo Nagel <tnagel@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: drop changes in chelsio] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The problem is that we were putting the NUL terminator too far:
buf[sizeof(buf) - 1] = '\0';
If the user input isn't NUL terminated and they haven't initialized the
whole buffer then it leads to an info leak. The NUL terminator should
be:
buf[len - 1] = '\0';
Signed-off-by: Yihui Zeng <yzeng56@asu.edu> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
[heiko.carstens@de.ibm.com: keep semantics of how *lenp and *ppos are handled] Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When a card is disconnected while in use, the system waits until all
opened files are closed then releases the card. This is done via
put_device() of the card device in each device release code.
The recently reported mutex deadlock bug happens in this code path;
snd_timer_close() for the timer device deals with the global
register_mutex and it calls put_device() there. When this timer
device is the last one, the card gets freed and it eventually calls
snd_timer_free(), which has again the protection with the global
register_mutex -- boom.
Basically put_device() call itself is race-free, so a relative simple
workaround is to move this put_device() call out of the mutex. For
achieving that, in this patch, snd_timer_close_locked() got a new
argument to store the card device pointer in return, and each caller
invokes put_device() with the returned object after the mutex unlock.
Reported-and-tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The clean up commit 41672c0c24a6 ("ALSA: timer: Simplify error path in
snd_timer_open()") unified the error handling code paths with the
standard goto, but it introduced a subtle bug: the timer instance is
stored in snd_timer_open() incorrectly even if it returns an error.
This may eventually lead to UAF, as spotted by fuzzer.
The culprit is the snd_timer_open() code checks the
SNDRV_TIMER_IFLG_EXCLUSIVE flag with the common variable timeri.
This variable is supposed to be the newly created instance, but we
(ab-)used it for a temporary check before the actual creation of a
timer instance. After that point, there is another check for the max
number of instances, and it bails out if over the threshold. Before
the refactoring above, it worked fine because the code returned
directly from that point. After the refactoring, however, it jumps to
the unified error path that stores the timeri variable in return --
even if it returns an error. Unfortunately this stored value is kept
in the caller side (snd_timer_user_tselect()) in tu->timeri. This
causes inconsistency later, as if the timer was successfully
assigned.
In this patch, we fix it by not re-using timeri variable but a
temporary variable for testing the exclusive connection, so timeri
remains NULL at that point.
Just a minor refactoring to use the standard goto for error paths in
snd_timer_open() instead of open code. The first mutex_lock() is
moved to the beginning of the function to make the code clearer.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
[bwh: Backported to 3.16 as dependency of commit a39331867335
"ALSA: timer: Fix mutex deadlock at releasing card"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Mesh path nexthop should be a ethernet address, but current validation
checks against 4 byte integers.
Fixes: 2ec600d672e74 ("nl80211/cfg80211: support for mesh, sta dumping") Signed-off-by: Markus Theil <markus.theil@tu-ilmenau.de> Link: https://lore.kernel.org/r/20191029093003.10355-1-markus.theil@tu-ilmenau.de Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This happens because __ceph_remove_cap() may queue a cap release
(__ceph_queue_cap_release) which can be scheduled before that cap is
removed from the inode list with
rb_erase(&cap->ci_node, &ci->i_caps);
And, when this finally happens, the use-after-free will occur.
This can be fixed by removing the cap from the inode list before being
removed from the session list, and thus eliminating the risk of an UAF.
Signed-off-by: Luis Henriques <lhenriques@suse.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Endpoints with a maxpacket length of 0 are probably useless. They
can't transfer any data, and it's not at all unlikely that a UDC will
crash or hang when trying to handle a non-zero-length usb_request for
such an endpoint. Indeed, dummy-hcd gets a divide error when trying
to calculate the remainder of a transfer length by the maxpacket
value, as discovered by the syzbot fuzzer.
Currently the gadget core does not check for endpoints having a
maxpacket value of 0. This patch adds a check to usb_ep_enable(),
preventing such endpoints from being used.
As far as I know, none of the gadget drivers in the kernel tries to
create an endpoint with maxpacket = 0, but until now there has been
nothing to prevent userspace programs under gadgetfs or configfs from
doing it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-and-tested-by: syzbot+8ab8bf161038a8768553@syzkaller.appspotmail.com Acked-by: Felipe Balbi <balbi@kernel.org> Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.1910281052370.1485-100000@iolanthe.rowland.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
sk_page_frag() optimizes skb_frag allocations by using per-task
skb_frag cache when it knows it's the only user. The condition is
determined by seeing whether the socket allocation mask allows
blocking - if the allocation may block, it obviously owns the task's
context and ergo exclusively owns current->task_frag.
Unfortunately, this misses recursion through memory reclaim path.
Please take a look at the following backtrace.
In [0], tcp_send_msg_locked() was using current->page_frag when it
called sk_wmem_schedule(). It already calculated how many bytes can
be fit into current->page_frag. Due to memory pressure,
sk_wmem_schedule() called into memory reclaim path which called into
xfs and then IO issue path. Because the filesystem in question is
backed by nbd, the control goes back into the tcp layer - back into
tcp_sendmsg_locked().
nbd sets sk_allocation to (GFP_NOIO | __GFP_MEMALLOC) which makes
sense - it's in the process of freeing memory and wants to be able to,
e.g., drop clean pages to make forward progress. However, this
confused sk_page_frag() called from [2]. Because it only tests
whether the allocation allows blocking which it does, it now thinks
current->page_frag can be used again although it already was being
used in [0].
After [2] used current->page_frag, the offset would be increased by
the used amount. When the control returns to [0],
current->page_frag's offset is increased and the previously calculated
number of bytes now may overrun the end of allocated memory leading to
silent memory corruptions.
Fix it by adding gfpflags_normal_context() which tests sleepable &&
!reclaim and use it to determine whether to use current->task_frag.
v2: Eric didn't like gfp flags being tested twice. Introduce a new
helper gfpflags_normal_context() and combine the two tests.
Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Josef Bacik <josef@toxicpanda.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: Keep testing __GFP_WAIT flag instead of
__GFP_DIRECT_RECLAIM.] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The custom ring-buffer implementation was merged without any locking or
explicit memory barriers, but a spinlock was later added by commit 9d33efd9a791 ("USB: ldusb bugfix").
The lock did not cover the update of the tail index once the entry had
been processed, something which could lead to memory corruption on
weakly ordered architectures or due to compiler optimisations.
Specifically, a completion handler running on another CPU might observe
the incremented tail index and update the entry before ld_usb_read() is
done with it.
It is not allowed to sleep to early in the boot process and this may lead
to kernel issues if the bootloader didn't prepare the slow clock and main
clock.
This results in the following error and dump stack on the AriettaG25:
bad: scheduling from the idle thread!
Ensure it is possible to sleep, else simply have a delay.
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Link: https://lkml.kernel.org/r/20190920153906.20887-1-alexandre.belloni@bootlin.com Fixes: 80eded6ce8bb ("clk: at91: add slow clks driver") Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
[bwh: Backported to 3.16:
- Drop changes in clk_sama5d4_slow_osc_prepare()
- Adjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This saves us writing the IBS control MSR twice when disabling the
event.
I searched revision guides for all families since 10h, and did not
find occurrence of erratum #420, nor anything remotely similar:
so we isolate the secondary MSR write to family 10h only.
Also unconditionally update the count mask for IBS Op implementations
that have read & writeable current count (CurCnt) fields in addition
to the MaxCnt field. These bits were reserved on prior
implementations, and therefore shouldn't have negative impact.
Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: c9574fe0bdb9 ("perf/x86-ibs: Implement workaround for IBS erratum #420") Link: https://lkml.kernel.org/r/20191023150955.30292-2-kim.phillips@amd.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 3.16:
- Don't update the count mask; we don't use or define the CurCnt fields here
- Adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The loop that reads all the IBS MSRs into *buf stopped one MSR short of
reading the IbsOpData register, which contains the RipInvalid status bit.
Fix the offset_max assignment so the MSR gets read, so the RIP invalid
evaluation is based on what the IBS h/w output, instead of what was
left in memory.
Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: d47e8238cd76 ("perf/x86-ibs: Take instruction pointer from ibs sample") Link: https://lkml.kernel.org/r/20191023150955.30292-1-kim.phillips@amd.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fix interrupt storm generated by endpoints when working in FIFO mode.
The TX_COMPLETE interrupt is used only by control endpoints processing.
Do not enable it for other types of endpoints.
Fixes: 914a3f3b3754 ("USB: add atmel_usba_udc driver") Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Properly save and restore all top PLL related configuration registers
during suspend/resume cycle. So far driver only handled EPLL and RPLL
clocks, all other were reset to default values after suspend/resume cycle.
This caused for example lower G3D (MALI Panfrost) performance after system
resume, even if performance governor has been selected.
Reported-by: Reported-by: Marian Mihailescu <mihailescu2m@gmail.com> Fixes: 773424326b51 ("clk: samsung: exynos5420: add more registers to restore list") Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The IFF_BONDING means bonding master or bonding slave device.
->ndo_add_slave() sets IFF_BONDING flag and ->ndo_del_slave() unsets
IFF_BONDING flag.
bond0<--bond1
Both bond0 and bond1 are bonding device and these should keep having
IFF_BONDING flag until they are removed.
But bond1 would lose IFF_BONDING at ->ndo_del_slave() because that routine
do not check whether the slave device is the bonding type or not.
This patch adds the interface type check routine before removing
IFF_BONDING flag.
Test commands:
ip link add bond0 type bond
ip link add bond1 type bond
ip link set bond1 master bond0
ip link set bond1 nomaster
ip link del bond1 type bond
ip link add bond1 type bond
Fixes: 0b680e753724 ("[PATCH] bonding: Add priv_flag to avoid event mishandling") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
BUG: KCSAN: data-race in update_defense_level / update_defense_level
read to 0xffffffff861a6260 of 4 bytes by task 3006 on cpu 1:
update_defense_level+0x621/0xb30 net/netfilter/ipvs/ip_vs_ctl.c:177
defense_work_handler+0x3d/0xd0 net/netfilter/ipvs/ip_vs_ctl.c:225
process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
worker_thread+0xa0/0x800 kernel/workqueue.c:2415
kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352
write to 0xffffffff861a6260 of 4 bytes by task 7333 on cpu 0:
update_defense_level+0xa62/0xb30 net/netfilter/ipvs/ip_vs_ctl.c:205
defense_work_handler+0x3d/0xd0 net/netfilter/ipvs/ip_vs_ctl.c:225
process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
worker_thread+0xa0/0x800 kernel/workqueue.c:2415
kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7333 Comm: kworker/0:5 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events defense_work_handler
Indeed, old_secure_tcp is currently a static variable, while it
needs to be a per netns variable.
Fixes: a0840e2e165a ("IPVS: netns, ip_vs_ctl local vars moved to ipvs struct.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Simon Horman <horms@verge.net.au> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
build_restore_pagemask() will restore the value of register $1/$at when
its restore_scratch argument is non-zero, and aims to do so by filling a
branch delay slot. Commit 0b24cae4d535 ("MIPS: Add missing EHB in mtc0
-> mfc0 sequence.") added an EHB instruction (Execution Hazard Barrier)
prior to restoring $1 from a KScratch register, in order to resolve a
hazard that can result in stale values of the KScratch register being
observed. In particular, P-class CPUs from MIPS with out of order
execution pipelines such as the P5600 & P6600 are affected.
Unfortunately this EHB instruction was inserted in the branch delay slot
causing the MFC0 instruction which performs the restoration to no longer
execute along with the branch. The result is that the $1 register isn't
actually restored, ie. the TLB refill exception handler clobbers it -
which is exactly the problem the EHB is meant to avoid for the P-class
CPUs.
Similarly build_get_pgd_vmalloc() will restore the value of $1/$at when
its mode argument equals refill_scratch, and suffers from the same
problem.
Fix this by in both cases moving the EHB earlier in the emitted code.
There's no reason it needs to immediately precede the MFC0 - it simply
needs to be between the MTC0 & MFC0.
This bug only affects Cavium Octeon systems which use
build_fast_tlb_refill_handler().
Signed-off-by: Paul Burton <paulburton@kernel.org> Fixes: 0b24cae4d535 ("MIPS: Add missing EHB in mtc0 -> mfc0 sequence.") Cc: Dmitry Korotin <dkorotin@wavecomp.com> Cc: linux-mips@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The vectors span more than one byte, so mark them as arrays.
Fixes the following build error when building when using GCC 8.3:
In file included from ./include/linux/string.h:19,
from ./include/linux/bitmap.h:9,
from ./include/linux/cpumask.h:12,
from ./arch/mips/include/asm/processor.h:15,
from ./arch/mips/include/asm/thread_info.h:16,
from ./include/linux/thread_info.h:38,
from ./include/asm-generic/preempt.h:5,
from ./arch/mips/include/generated/asm/preempt.h:1,
from ./include/linux/preempt.h:81,
from ./include/linux/spinlock.h:51,
from ./include/linux/mmzone.h:8,
from ./include/linux/bootmem.h:8,
from arch/mips/bcm63xx/prom.c:10:
arch/mips/bcm63xx/prom.c: In function 'prom_init':
./arch/mips/include/asm/string.h:162:11: error: '__builtin_memcpy' forming offset [2, 32] is out of the bounds [0, 1] of object 'bmips_smp_movevec' with type 'char' [-Werror=array-bounds]
__ret = __builtin_memcpy((dst), (src), __len); \
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/mips/bcm63xx/prom.c:97:3: note: in expansion of macro 'memcpy'
memcpy((void *)0xa0000200, &bmips_smp_movevec, 0x20);
^~~~~~
In file included from arch/mips/bcm63xx/prom.c:14:
./arch/mips/include/asm/bmips.h:80:13: note: 'bmips_smp_movevec' declared here
extern char bmips_smp_movevec;
Fixes: 18a1eef92dcd ("MIPS: BMIPS: Introduce bmips.h") Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Paul Burton <paulburton@kernel.org> Cc: linux-mips@vger.kernel.org Cc: Ralf Baechle <ralf@linux-mips.org> Cc: James Hogan <jhogan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When our call to get the external clock fails, we forget to clean up
the enabled internal clock correctly. Enable the clock after we have
obtained all our resources.
Fixes: 84aac6c79bfd ("ASoC: kirkwood: fix loss of external clock at probe time") Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Link: https://lore.kernel.org/r/E1iNGyK-0004oF-6A@rmk-PC.armlinux.org.uk Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If writeback cache is enabled, then writes might get reordered with
chmod/chown/utimes. The problem with this is that performing the write in
the fuse daemon might itself change some of these attributes. In such case
the following sequence of operations will result in file ending up with the
wrong mode, for example:
int fd = open ("suid", O_WRONLY|O_CREAT|O_EXCL);
write (fd, "1", 1);
fchown (fd, 0, 0);
fchmod (fd, 04755);
close (fd);
This patch fixes this by flushing pending writes before performing
chown/chmod/utimes.
Reported-by: Giuseppe Scrivano <gscrivan@redhat.com> Tested-by: Giuseppe Scrivano <gscrivan@redhat.com> Fixes: 4d99ff8f12eb ("fuse: Turn writeback cache on") Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
A customer reports that after a devloss, an ADISC failure is logged. It
turns out the ADISC flag is set even the user explicitly set lpfc_use_adisc
= 0.
[Sat Dec 22 22:55:58 2018] lpfc 0000:82:00.0: 2:(0):0203 Devloss timeout on WWPN 50:01:43:80:12:8e:40:20 NPort x05df00 Data: x82000000 x8 xa
[Sat Dec 22 23:08:20 2018] lpfc 0000:82:00.0: 2:(0):2755 ADISC failure DID:05DF00 Status:x9/x70000
[mkp: fixed Hannes' email]
Fixes: 92d7f7b0cde3 ("[SCSI] lpfc: NPIV: add NPIV support on top of SLI-3") Cc: Dick Kennedy <dick.kennedy@broadcom.com> Cc: James Smart <james.smart@broadcom.com> Link: https://lore.kernel.org/r/20191022072112.132268-1-dwagner@suse.de Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: James Smart <james.smart@broadcom.com> Signed-off-by: Daniel Wagner <dwagner@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
8-letter strings representing ARC perf events are stores in two
32-bit registers as ASCII characters like that: "IJMP", "IALL", "IJMPTAK" etc.
And the same order of bytes in the word is used regardless CPU endianness.
Which means in case of big-endian CPU core we need to swap bytes to get
the same order as if it was on little-endian CPU.
Otherwise we're seeing the following error message on boot:
------------------------->8----------------------
ARC perf : 8 counters (32 bits), 40 conditions, [overflow IRQ support]
sysfs: cannot create duplicate filename '/devices/arc_pct/events/pmji'
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.2.18 #3
Stack Trace:
arc_unwind_core+0xd4/0xfc
dump_stack+0x64/0x80
sysfs_warn_dup+0x46/0x58
sysfs_add_file_mode_ns+0xb2/0x168
create_files+0x70/0x2a0
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at kernel/events/core.c:12144 perf_event_sysfs_init+0x70/0xa0
Failed to register pmu: arc_pct, reason -17
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.2.18 #3
Stack Trace:
arc_unwind_core+0xd4/0xfc
dump_stack+0x64/0x80
__warn+0x9c/0xd4
warn_slowpath_fmt+0x22/0x2c
perf_event_sysfs_init+0x70/0xa0
---[ end trace a75fb9a9837bd1ec ]---
------------------------->8----------------------
What happens here we're trying to register more than one raw perf event
with the same name "PMJI". Why? Because ARC perf events are 4 to 8 letters
and encoded into two 32-bit words. In this particular case we deal with 2
events:
* "IJMP____" which counts all jump & branch instructions
* "IJMPC___" which counts only conditional jumps & branches
Those strings are split in two 32-bit words this way "IJMP" + "____" &
"IJMP" + "C___" correspondingly. Now if we read them swapped due to CPU core
being big-endian then we read "PMJI" + "____" & "PMJI" + "___C".
And since we interpret read array of ASCII letters as a null-terminated string
on big-endian CPU we end up with 2 events of the same name "PMJI".
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
According to MS-CIFS specification MID 0xFFFF should not be used by the
CIFS client, but we actually do. Besides, this has proven to cause races
leading to oops between SendReceive2/cifs_demultiplex_thread. On SMB1,
MID is a 2 byte value easy to reach in CurrentMid which may conflict with
an oplock break notification request coming from server
Signed-off-by: Roberto Bergantinos Corpas <rbergant@redhat.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If packet corruption failed we jump to finish_segs and return
NET_XMIT_SUCCESS. Seeing success will make the parent qdisc
increment its backlog, that's incorrect - we need to return
NET_XMIT_DROP.
Fixes: 6071bd1aa13e ("netem: Segment GSO packets on enqueue") Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
xenvif_connect_data() calls module_put() in case of error. This is
wrong as there is no related module_get().
Remove the superfluous module_put().
Fixes: 279f438e36c0a7 ("xen-netback: Don't destroy the netdev until the vif is shut down") Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Paul Durrant <paul@xen.org> Reviewed-by: Wei Liu <wei.liu@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fix broken read implementation, which could be used to trigger slab info
leaks.
The driver failed to check if the custom ring buffer was still empty
when waking up after having waited for more data. This would happen on
every interrupt-in completion, even if no data had been added to the
ring buffer (e.g. on disconnect events).
Due to missing sanity checks and uninitialised (kmalloced) ring-buffer
entries, this meant that huge slab info leaks could easily be triggered.
Note that the empty-buffer check after wakeup is enough to fix the info
leak on disconnect, but let's clear the buffer on allocation and add a
sanity check to read() to prevent further leaks.
Fixes: 2824bd250f0b ("[PATCH] USB: add ldusb driver") Reported-by: syzbot+6fe95b826644f7f12b0b@syzkaller.appspotmail.com Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20191018151955.25135-2-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The EPHY integrated into the 40nm Set-Top Box devices can falsely
detect energy when connected to a disabled peer interface. When the
peer interface is enabled the EPHY will detect and report the link
as active, but on occasion may get into a state where it is not
able to exchange data with the connected GENET MAC. This issue has
not been observed when the link parameters are auto-negotiated;
however, it has been observed with a manually configured link.
It has been empirically determined that issuing a soft reset to the
EPHY when energy is detected prevents it from getting into this bad
state.
Fixes: 1c1008c793fa ("net: bcmgenet: add main driver file") Signed-off-by: Doug Berger <opendmb@gmail.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The internal 40nm EPHYs use a "Workaround for putting the PHY in
IDDQ mode." These PHYs require a soft reset to restore functionality
after they are powered back up.
This commit defines the soft_reset function to use genphy_soft_reset
during phy_init_hw to accommodate this.
Fixes: 6e2d85ec0559 ("net: phy: Stop with excessive soft reset") Signed-off-by: Doug Berger <opendmb@gmail.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16:
- Delete trailing backslash; there is a single entry for 40 nm PHYs
and not a macro definition
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
We have a test case like block/001 in blktests, which will create a scsi
device by loading scsi_debug module and then try to delete the device by
sysfs interface. At the same time, it may remove the scsi_debug module.
And getting a invalid paging request BUG_ON as following:
During deleting scsi target, the scsi_debug module have been removed. Then,
sdebug_driver_template belonged to the module cannot be accessd, resulting
in scsi_proc_hostdir_rm() BUG_ON.
To fix the bug, we add scsi_device_get() in sdev_store_delete() to try to
increase refcount of module, avoiding the module been removed.
Link: https://lore.kernel.org/r/20191015130556.18061-1-yuyufen@huawei.com Signed-off-by: Yufen Yu <yuyufen@huawei.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
We were checking for the full fsync flag in the inode before locking the
inode, which is racy, since at that that time it might not be set but
after we acquire the inode lock some other task set it. One case where
this can happen is on a system low on memory and some concurrent task
failed to allocate an extent map and therefore set the full sync flag on
the inode, to force the next fsync to work in full mode.
A consequence of missing the full fsync flag set is hitting the problems
fixed by commit 0c713cbab620 ("Btrfs: fix race between ranged fsync and
writeback of adjacent ranges"), BUG_ON() when dropping extents from a log
tree, hitting assertion failures at tree-log.c:copy_items() or all sorts
of weird inconsistencies after replaying a log due to file extents items
representing ranges that overlap.
So just move the check such that it's done after locking the inode and
before starting writeback again.
Fixes: 0c713cbab620 ("Btrfs: fix race between ranged fsync and writeback of adjacent ranges") Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
[bwh: Backported to 3.16:
- Keep the "len" variable since we pass it to btrfs_wait_ordered_range()
in two different places here
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fix races between closing a port and opening or closing another port on
the same device which could lead to a failure to start or stop the
shared interrupt URB. The latter could potentially cause a
use-after-free or worse in the completion handler on driver unbind.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
tc_ctl_action() has the ability to loop forever if tcf_action_add()
returns -EAGAIN.
This special case has been done in case a module needed to be loaded,
but it turns out that tcf_add_notify() could also return -EAGAIN
if the socket sk_rcvbuf limit is hit.
We need to separate the two cases, and only loop for the module
loading case.
While we are at it, add a limit of 10 attempts since unbounded
loops are always scary.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot+cf0adbb9c28c8866c788@syzkaller.appspotmail.com Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
There is an arbitrary difference between the system resume and
runtime resume code paths for PCI devices regarding the delay to
apply when switching the devices from D3cold to D0.
Namely, pci_restore_standard_config() used in the runtime resume
code path calls pci_set_power_state() which in turn invokes
__pci_start_power_transition() to power up the device through the
platform firmware and that function applies the transition delay
(as per PCI Express Base Specification Revision 2.0, Section 6.6.1).
However, pci_pm_default_resume_early() used in the system resume
code path calls pci_power_up() which doesn't apply the delay at
all and that causes issues to occur during resume from
suspend-to-idle on some systems where the delay is required.
Since there is no reason for that difference to exist, modify
pci_power_up() to follow pci_set_power_state() more closely and
invoke __pci_start_power_transition() from there to call the
platform firmware to power up the device (in case that's necessary).
A recent commit addressing a runtime PM use-count regression, introduced
a use-after-free by not making sure we held a reference to the struct
usb_interface for the lifetime of the driver data.
Fixes: 9a31535859bf ("USB: usblp: fix runtime PM after driver unbind") Reported-by: syzbot+cd24df4d075c319ebfc5@syzkaller.appspotmail.com Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20191015175522.18490-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
It seems that the right variable to use in this case is *i*, instead of
*n*, otherwise there is an undefined behavior when right shifiting by more
than 31 bits when multiplying n by 8; notice that *n* can take values
equal or greater than 4 (4, 8, 16, ...).
Also, notice that under the current conditions (bl = 3), we are skiping
the handling of bytes 3, 7, 31... So, fix this by updating this logic
and limit *bl* up to 4 instead of up to 3.
This fix is based on function udc_stuff_fifo().
Addresses-Coverity-ID: 1454834 ("Bad bit shift operation") Fixes: 24a28e428351 ("USB: gadget driver for LPC32xx") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Link: https://lore.kernel.org/r/20191014191830.GA10721@embeddedor Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If disconnect() races with release() after a process has been
interrupted, release() could end up returning early and the driver would
fail to free its driver data.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20191010125835.27031-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If disconnect() races with release() after a process has been
interrupted, release() could end up returning early and the driver would
fail to free its driver data.
In the future, we're going to want to extend the ceph_reply_info_extra
for create replies. Currently though, the kernel code doesn't accept an
extra blob that is larger than the expected data.
Change the code to skip over any unrecognized fields at the end of the
extra blob, rather than returning -EIO.
Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Custom outs*/ins* implementations are long gone from the xtensa port,
remove matching EXPORT_SYMBOLs.
This fixes the following build warnings issued by modpost since commit 15bfc2348d54 ("modpost: check for static EXPORT_SYMBOL* functions"):
WARNING: "insb" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "insw" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "insl" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "outsb" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "outsw" [vmlinux] is a static EXPORT_SYMBOL
WARNING: "outsl" [vmlinux] is a static EXPORT_SYMBOL
Fixes: d38efc1f150f ("xtensa: adopt generic io routines") Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
A long time ago we fixed a similar deadlock in show_slab_objects() [1].
However, it is apparently due to the commits like 01fb58bcba63 ("slab:
remove synchronous synchronize_sched() from memcg cache deactivation
path") and 03afc0e25f7f ("slab: get_online_mems for
kmem_cache_{create,destroy,shrink}"), this kind of deadlock is back by
just reading files in /sys/kernel/slab which will generate a lockdep
splat below.
Since the "mem_hotplug_lock" here is only to obtain a stable online node
mask while racing with NUMA node hotplug, in the worst case, the results
may me miscalculated while doing NUMA node hotplug, but they shall be
corrected by later reads of the same files.
WARNING: possible circular locking dependency detected
------------------------------------------------------
cat/5224 is trying to acquire lock: ffff900012ac3120 (mem_hotplug_lock.rw_sem){++++}, at:
show_slab_objects+0x94/0x3a8
but task is already holding lock: b8ff009693eee398 (kn->count#45){++++}, at: kernfs_seq_start+0x44/0xf0
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
I think it is important to mention that this doesn't expose the
show_slab_objects to use-after-free. There is only a single path that
might really race here and that is the slab hotplug notifier callback
__kmem_cache_shrink (via slab_mem_going_offline_callback) but that path
doesn't really destroy kmem_cache_node data structures.
Sven noticed that calling ioremap() and iounmap() multiple times leads
to a vmap memory leak:
vmap allocation for size 4198400 failed:
use vmalloc=<size> to increase size
It seems we missed calling vunmap() in iounmap().
Signed-off-by: Helge Deller <deller@gmx.de> Noticed-by: Sven Schnelle <svens@stackframe.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Each slave interface of an B.A.T.M.A.N. IV virtual interface has an OGM
packet buffer which is initialized using data from netdevice notifier and
other rtnetlink related hooks. It is sent regularly via various slave
interfaces of the batadv virtual interface and in this process also
modified (realloced) to integrate additional state information via TVLV
containers.
It must be avoided that the worker item is executed without a common lock
with the netdevice notifier/rtnetlink helpers. Otherwise it can either
happen that half modified/freed data is sent out or functions modifying the
OGM buffer try to access already freed memory regions.
Reported-by: syzbot+0cc629f19ccb8534935b@syzkaller.appspotmail.com Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
[bwh: Backported to 3.16:
- Don't add status check in batadv_iv_ogm_schedule()
- Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Directly return error values. No need to use a return variable.
Signed-off-by: Markus Pargmann <mpa@pengutronix.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
[bwh: Backported to 3.16 as dependency of commit 40e220b4218b
"batman-adv: Avoid free/alloc race when handling OGM buffer"] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
As instances may have different tracers available, we need to look at the
trace_array descriptor that shows the list of the available tracers for the
instance. But there's a race between opening the file and an admin
deleting the instance. The trace_array_get() needs to be called before
accessing the trace_array.
Fixes: 607e2ea167e56 ("tracing: Set up infrastructure to allow tracers for instances") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The driver was using its struct usb_interface pointer as an inverted
disconnected flag, but was setting it to NULL without making sure all
code paths that used it were done with it.
Before commit ef61eb43ada6 ("USB: yurex: Fix protection fault after
device removal") this included the interrupt-in completion handler, but
there are further accesses in dev_err and dev_dbg statements in
yurex_write() and the driver-data destructor (sic!).
Fix this by unconditionally stopping also the control URB at disconnect
and by using a dedicated disconnected flag.
Note that we need to take a reference to the struct usb_interface to
avoid a use-after-free in the destructor whenever the device was
disconnected while the character device was still open.
The driver was accessing its struct usb_interface from its release()
callback without holding a reference. This would lead to a
use-after-free whenever debugging was enabled and the device was
disconnected while its character device was open.
Fixes: 549e83500b80 ("USB: iowarrior: Convert local dbg macro to dev_dbg") Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20191009104846.5925-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The driver was accessing its struct usb_device in its release()
callback without holding a reference. This would lead to a
use-after-free whenever the device was disconnected while the character
device was still open.
The driver was using its struct usb_interface pointer as an inverted
disconnected flag, but was setting it to NULL before making sure all
completion handlers had run. This could lead to a NULL-pointer
dereference in a number of dev_dbg, dev_warn and dev_err statements in
the completion handlers which relies on said pointer.
Fix this by unconditionally stopping all I/O and preventing
resubmissions by poisoning the interrupt URBs at disconnect and using a
dedicated disconnected flag.
This also makes sure that all I/O has completed by the time the
disconnect callback returns.
Fixes: 2824bd250f0b ("[PATCH] USB: add ldusb driver") Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20191009153848.8664-4-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The driver was accessing its struct usb_device in its release()
callback without holding a reference. This would lead to a
use-after-free whenever the device was disconnected while the character
device was still open.
The driver was using its struct usb_interface pointer as an inverted
disconnected flag and was setting it to NULL before making sure all
completion handlers had run. This could lead to NULL-pointer
dereferences in the dev_err() statements in the completion handlers
which relies on said pointer.
Fix this by using a dedicated disconnected flag.
Note that this is also addresses a NULL-pointer dereference at release()
and a struct usb_interface reference leak introduced by a recent runtime
PM fix, which depends on and should have been submitted together with
this patch.
When the system has high memory pressure, the page containing the
instruction may be paged out. Using probe_kernel_address() means that
if the page is swapped out, the resulting page fault will not be
handled because page faults are disabled by this function.
Use get_user() to read the instruction instead.
Reported-by: Jing Xiangfeng <jingxiangfeng@huawei.com> Fixes: b255188f90e2 ("ARM: fix scheduling while atomic warning in alignment handling code") Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If the quota/period ratio was changed during this scaling due to
precision loss, it will cause inconsistency between parent and child
task groups.
See below example:
A userspace container manager (kubelet) does three operations:
1) Create a parent cgroup, set quota to 1,000us and period to 10,000us.
2) Create a few children cgroups.
3) Set quota to 1,000us and period to 10,000us on a child cgroup.
These operations are expected to succeed. However, if the scaling of
147/128 happens before step 3, quota and period of the parent cgroup
will be changed:
Mark inode for force revalidation if LOOKUP_REVAL flag is set.
This tells the client to actually send a QueryInfo request to
the server to obtain the latest metadata in case a directory
or a file were changed remotely. Only do that if the client
doesn't have a lease for the file to avoid unneeded round
trips to the server.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
[bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Currently the client indicates that a dentry is stale when inode
numbers or type types between a local inode and a remote file
don't match. If this is the case attributes is not being copied
from remote to local, so, it is already known that the local copy
has stale metadata. That's why the inode needs to be marked for
revalidation in order to tell the VFS to lookup the dentry again
before openning a file. This prevents unexpected stale errors
to be returned to the user space when openning a file.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Commit 7196ac113a4f ("Fix to check Unique id and FileType when client
refer file directly.") checks whether the uniqueid of an inode has
changed when getting the inode info, but only when using the UNIX
extensions. Add a similar check for SMB2+, since this can be done
without an extra network roundtrip.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When you refer file directly on cifs client,
(e.g. ls -li <filename>, cd <dir>, stat <filename>)
the function return old inode number and filetype from old inode cache,
though server has different inode number or filetype.
When server is Windows, cifs client has same problem.
When Server is Windows
, This patch fixes bug in different filetype,
but does not fix bug in different inode number.
Because QUERY_PATH_INFO response by Windows does not include inode number(Index Number) .
BUG INFO
https://bugzilla.kernel.org/show_bug.cgi?id=90021
https://bugzilla.kernel.org/show_bug.cgi?id=90031
Reported-by: Nakajima Akira <nakajima.akira@nttcom.co.jp> Signed-off-by: Nakajima Akira <nakajima.akira@nttcom.co.jp> Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The bug is that llc_sap_state_process() always takes an extra reference
to the skb, but sometimes neither llc_sap_next_state() nor
llc_sap_state_process() itself drops this reference.
Fix it by changing llc_sap_next_state() to never consume a reference to
the skb, rather than sometimes do so and sometimes not. Then remove the
extra skb_get() and kfree_skb() from llc_sap_state_process().
Reported-by: syzbot+6bf095f9becf5efef645@syzkaller.appspotmail.com Reported-by: syzbot+31c16aa4202dace3812e@syzkaller.appspotmail.com Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Calling 'panic()' on a kernel with CONFIG_PREEMPT=y can leave the
calling CPU in an infinite loop, but with interrupts and preemption
enabled. From this state, userspace can continue to be scheduled,
despite the system being "dead" as far as the kernel is concerned.
This is easily reproducible on arm64 when booting with "nosmp" on the
command line; a couple of shell scripts print out a periodic "Ping"
message whilst another triggers a crash by writing to
/proc/sysrq-trigger:
Currently if the client identifies problems when processing
metadata returned in CREATE response, the open handle is being
leaked. This causes multiple problems like a file missing a lease
break by that client which causes high latencies to other clients
accessing the file. Another side-effect of this is that the file
can't be deleted.
Fix this by closing the file after the client hits an error after
the file was opened and the open descriptor wasn't returned to
the user space. Also convert -ESTALE to -EOPENSTALE to allow
the VFS to revalidate a dentry and retry the open.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 30cc4587659e ("NFC: Move LLCP code to the NFC top level diirectory") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 758cc43c6d73 ("[PKT_SCHED]: Fix dsmark to apply changes consistent") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Since commit c09551c6ff7f ("net: ipv4: use a dedicated counter
for icmp_v4 redirect packets") we use 'n_redirects' to account
for redirect packets, but we still use 'rate_tokens' to compute
the redirect packets exponential backoff.
If the device sent to the relevant peer any ICMP error packet
after sending a redirect, it will also update 'rate_token' according
to the leaking bucket schema; typically 'rate_token' will raise
above BITS_PER_LONG and the redirect packets backoff algorithm
will produce undefined behavior.
Fix the issue using 'n_redirects' to compute the exponential backoff
in ip_rt_send_redirect().
Note that we still clear rate_tokens after a redirect silence period,
to avoid changing an established behaviour.
The root cause predates git history; before the mentioned commit in
the critical scenario, the kernel stopped sending redirects, after
the mentioned commit the behavior more randomic.
Reported-by: Xiumei Mu <xmu@redhat.com> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Fixes: c09551c6ff7f ("net: ipv4: use a dedicated counter for icmp_v4 redirect packets") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
According to the algorithm described in the comment block at the
beginning of ip_rt_send_redirect, the host should try to send
'ip_rt_redirect_number' ICMP redirect packets with an exponential
backoff and then stop sending them at all assuming that the destination
ignores redirects.
If the device has previously sent some ICMP error packets that are
rate-limited (e.g TTL expired) and continues to receive traffic,
the redirect packets will never be transmitted. This happens since
peer->rate_tokens will be typically greater than 'ip_rt_redirect_number'
and so it will never be reset even if the redirect silence timeout
(ip_rt_redirect_silence) has elapsed without receiving any packet
requiring redirects.
Fix it by using a dedicated counter for the number of ICMP redirect
packets that has been sent by the host
I have not been able to identify a given commit that introduced the
issue since ip_rt_send_redirect implements the same rate-limiting
algorithm from commit 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: adjust context, indentation] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
projects / linux-stable / log