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467,775 commits

Author SHA1 Message Date
Stephane Eranian
fcd707df87 perf/core: Restore mmap record type correctly
commit d9c1bb2f6a upstream.

On mmap(), perf_events generates a RECORD_MMAP record and then checks
which events are interested in this record. There are currently 2
versions of mmap records: RECORD_MMAP and RECORD_MMAP2. MMAP2 is larger.
The event configuration controls which version the user level tool
accepts.

If the event->attr.mmap2=1 field then MMAP2 record is returned.  The
perf_event_mmap_output() takes care of this. It checks attr->mmap2 and
corrects the record fields before putting it in the sampling buffer of
the event.  At the end the function restores the modified MMAP record
fields.

The problem is that the function restores the size but not the type.
Thus, if a subsequent event only accepts MMAP type, then it would
instead receive an MMAP2 record with a size of MMAP record.

This patch fixes the problem by restoring the record type on exit.

Signed-off-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Fixes: 13d7a2410f ("perf: Add attr->mmap2 attribute to an event")
Link: http://lkml.kernel.org/r/20190307185233.225521-1-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-08-13 12:38:40 +01:00
Georg Ottinger
82bbd92e6f iio: adc: at91: disable adc channel interrupt in timeout case
commit 09c6bdee51 upstream.

Having a brief look at at91_adc_read_raw() it is obvious that in the case
of a timeout the setting of AT91_ADC_CHDR and AT91_ADC_IDR registers is
omitted. If 2 different channels are queried we can end up with a
situation where two interrupts are enabled, but only one interrupt is
cleared in the interrupt handler. Resulting in a interrupt loop and a
system hang.

Signed-off-by: Georg Ottinger <g.ottinger@abatec.at>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-08-13 12:38:40 +01:00
Lars-Peter Clausen
f7803d78f8 iio: Fix scan mask selection
commit 20ea39ef9f upstream.

The trialmask is expected to have all bits set to 0 after allocation.
Currently kmalloc_array() is used which does not zero the memory and so
random bits are set. This results in random channels being enabled when
they shouldn't. Replace kmalloc_array() with kcalloc() which has the same
interface but zeros the memory.

Note the fix is actually required earlier than the below fixes tag, but
will require a manual backport due to move from kmalloc to kmalloc_array.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Fixes commit 057ac1acdf ("iio: Use kmalloc_array() in iio_scan_mask_set()").
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-08-13 12:38:40 +01:00
Markus Elfring
326b6adda0 iio: Use kmalloc_array() in iio_scan_mask_set()
commit 057ac1acdf upstream.

A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "kmalloc_array".

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-08-13 12:38:39 +01:00
Leonard Pollak
b8da660f62 Staging: iio: meter: fixed typo
commit 0a8a29be49 upstream.

This patch fixes an obvious typo, which will cause erroneously returning the Peak
Voltage instead of the Peak Current.

Signed-off-by: Leonard Pollak <leonardp@tr-host.de>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-08-13 12:38:39 +01:00
YueHaibing
056bd2ff27 xfrm: policy: Fix out-of-bound array accesses in __xfrm_policy_unlink
commit b805d78d30 upstream.

UBSAN report this:

UBSAN: Undefined behaviour in net/xfrm/xfrm_policy.c:1289:24
index 6 is out of range for type 'unsigned int [6]'
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.4.162-514.55.6.9.x86_64+ #13
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
 0000000000000000 1466cf39b41b23c9 ffff8801f6b07a58 ffffffff81cb35f4
 0000000041b58ab3 ffffffff83230f9c ffffffff81cb34e0 ffff8801f6b07a80
 ffff8801f6b07a20 1466cf39b41b23c9 ffffffff851706e0 ffff8801f6b07ae8
Call Trace:
 <IRQ>  [<ffffffff81cb35f4>] __dump_stack lib/dump_stack.c:15 [inline]
 <IRQ>  [<ffffffff81cb35f4>] dump_stack+0x114/0x1a0 lib/dump_stack.c:51
 [<ffffffff81d94225>] ubsan_epilogue+0x12/0x8f lib/ubsan.c:164
 [<ffffffff81d954db>] __ubsan_handle_out_of_bounds+0x16e/0x1b2 lib/ubsan.c:382
 [<ffffffff82a25acd>] __xfrm_policy_unlink+0x3dd/0x5b0 net/xfrm/xfrm_policy.c:1289
 [<ffffffff82a2e572>] xfrm_policy_delete+0x52/0xb0 net/xfrm/xfrm_policy.c:1309
 [<ffffffff82a3319b>] xfrm_policy_timer+0x30b/0x590 net/xfrm/xfrm_policy.c:243
 [<ffffffff813d3927>] call_timer_fn+0x237/0x990 kernel/time/timer.c:1144
 [<ffffffff813d8e7e>] __run_timers kernel/time/timer.c:1218 [inline]
 [<ffffffff813d8e7e>] run_timer_softirq+0x6ce/0xb80 kernel/time/timer.c:1401
 [<ffffffff8120d6f9>] __do_softirq+0x299/0xe10 kernel/softirq.c:273
 [<ffffffff8120e676>] invoke_softirq kernel/softirq.c:350 [inline]
 [<ffffffff8120e676>] irq_exit+0x216/0x2c0 kernel/softirq.c:391
 [<ffffffff82c5edab>] exiting_irq arch/x86/include/asm/apic.h:652 [inline]
 [<ffffffff82c5edab>] smp_apic_timer_interrupt+0x8b/0xc0 arch/x86/kernel/apic/apic.c:926
 [<ffffffff82c5c985>] apic_timer_interrupt+0xa5/0xb0 arch/x86/entry/entry_64.S:735
 <EOI>  [<ffffffff81188096>] ? native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:52
 [<ffffffff810834d7>] arch_safe_halt arch/x86/include/asm/paravirt.h:111 [inline]
 [<ffffffff810834d7>] default_idle+0x27/0x430 arch/x86/kernel/process.c:446
 [<ffffffff81085f05>] arch_cpu_idle+0x15/0x20 arch/x86/kernel/process.c:437
 [<ffffffff8132abc3>] default_idle_call+0x53/0x90 kernel/sched/idle.c:92
 [<ffffffff8132b32d>] cpuidle_idle_call kernel/sched/idle.c:156 [inline]
 [<ffffffff8132b32d>] cpu_idle_loop kernel/sched/idle.c:251 [inline]
 [<ffffffff8132b32d>] cpu_startup_entry+0x60d/0x9a0 kernel/sched/idle.c:299
 [<ffffffff8113e119>] start_secondary+0x3c9/0x560 arch/x86/kernel/smpboot.c:245

The issue is triggered as this:

xfrm_add_policy
    -->verify_newpolicy_info  //check the index provided by user with XFRM_POLICY_MAX
			      //In my case, the index is 0x6E6BB6, so it pass the check.
    -->xfrm_policy_construct  //copy the user's policy and set xfrm_policy_timer
    -->xfrm_policy_insert
	--> __xfrm_policy_link //use the orgin dir, in my case is 2
	--> xfrm_gen_index   //generate policy index, there is 0x6E6BB6

then xfrm_policy_timer be fired

xfrm_policy_timer
   --> xfrm_policy_id2dir  //get dir from (policy index & 7), in my case is 6
   --> xfrm_policy_delete
      --> __xfrm_policy_unlink //access policy_count[dir], trigger out of range access

Add xfrm_policy_id2dir check in verify_newpolicy_info, make sure the computed dir is
valid, to fix the issue.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: e682adf021 ("xfrm: Try to honor policy index if it's supplied by user")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-08-13 12:38:38 +01:00
Xin Long
2b8d63b97d ipv6: check sk sk_type and protocol early in ip_mroute_set/getsockopt
commit 99253eb750 upstream.

Commit 5e1859fbcc ("ipv4: ipmr: various fixes and cleanups") fixed
the issue for ipv4 ipmr:

  ip_mroute_setsockopt() & ip_mroute_getsockopt() should not
  access/set raw_sk(sk)->ipmr_table before making sure the socket
  is a raw socket, and protocol is IGMP

The same fix should be done for ipv6 ipmr as well.

This patch can fix the panic caused by overwriting the same offset
as ipmr_table as in raw_sk(sk) when accessing other type's socket
by ip_mroute_setsockopt().

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-08-13 12:38:38 +01:00
Ben Hutchings
8eb43aebcd Linux 3.16.71 v3.16.71 2019-07-23 19:43:18 +01:00
Jann Horn
d5d5bd909a ptrace: Fix ->ptracer_cred handling for PTRACE_TRACEME
commit 6994eefb00 upstream.

Fix two issues:

When called for PTRACE_TRACEME, ptrace_link() would obtain an RCU
reference to the parent's objective credentials, then give that pointer
to get_cred().  However, the object lifetime rules for things like
struct cred do not permit unconditionally turning an RCU reference into
a stable reference.

PTRACE_TRACEME records the parent's credentials as if the parent was
acting as the subject, but that's not the case.  If a malicious
unprivileged child uses PTRACE_TRACEME and the parent is privileged, and
at a later point, the parent process becomes attacker-controlled
(because it drops privileges and calls execve()), the attacker ends up
with control over two processes with a privileged ptrace relationship,
which can be abused to ptrace a suid binary and obtain root privileges.

Fix both of these by always recording the credentials of the process
that is requesting the creation of the ptrace relationship:
current_cred() can't change under us, and current is the proper subject
for access control.

This change is theoretically userspace-visible, but I am not aware of
any code that it will actually break.

Fixes: 64b875f7ac ("ptrace: Capture the ptracer's creds not PT_PTRACE_CAP")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-23 19:43:17 +01:00
Ben Hutchings
cf2df8f107 Linux 3.16.70 v3.16.70 2019-07-09 22:04:23 +01:00
Eric Dumazet
188da790e1 netns: provide pure entropy for net_hash_mix()
commit 355b985537 upstream.

net_hash_mix() currently uses kernel address of a struct net,
and is used in many places that could be used to reveal this
address to a patient attacker, thus defeating KASLR, for
the typical case (initial net namespace, &init_net is
not dynamically allocated)

I believe the original implementation tried to avoid spending
too many cycles in this function, but security comes first.

Also provide entropy regardless of CONFIG_NET_NS.

Fixes: 0b4419162a ("netns: introduce the net_hash_mix "salt" for hashes")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Amit Klein <aksecurity@gmail.com>
Reported-by: Benny Pinkas <benny@pinkas.net>
Cc: Pavel Emelyanov <xemul@openvz.org>
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>
2019-07-09 22:04:22 +01:00
Takashi Iwai
a62393d7eb mwifiex: Fix heap overflow in mwifiex_uap_parse_tail_ies()
commit 69ae4f6aac upstream.

A few places in mwifiex_uap_parse_tail_ies() perform memcpy()
unconditionally, which may lead to either buffer overflow or read over
boundary.

This patch addresses the issues by checking the read size and the
destination size at each place more properly.  Along with the fixes,
the patch cleans up the code slightly by introducing a temporary
variable for the token size, and unifies the error path with the
standard goto statement.

Reported-by: huangwen <huangwen@venustech.com.cn>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
[bwh: Backported to 3.16:
 - The tail IEs are parsed in mwifiex_set_mgmt_ies, which looks for two
   specific IEs rather than looping
 - Check IE length against tail length after calling
   cfg80211_find_vendor_ie(), but not after cfg80211_find_ie() since that
   already does it
 - On error, return without calling mwifiex_set_mgmt_beacon_data_ies()
 - Drop inapplicable change to WMM IE handling
 - Adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:22 +01:00
Takashi Iwai
f287d86856 mwifiex: Abort at too short BSS descriptor element
commit 685c9b7750 upstream.

Currently mwifiex_update_bss_desc_with_ie() implicitly assumes that
the source descriptor entries contain the enough size for each type
and performs copying without checking the source size.  This may lead
to read over boundary.

Fix this by putting the source size check in appropriate places.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:21 +01:00
Takashi Iwai
a24ac7326f mwifiex: Fix possible buffer overflows at parsing bss descriptor
commit 13ec7f10b8 upstream.

mwifiex_update_bss_desc_with_ie() calls memcpy() unconditionally in
a couple places without checking the destination size.  Since the
source is given from user-space, this may trigger a heap buffer
overflow.

Fix it by putting the length check before performing memcpy().

This fix addresses CVE-2019-3846.

Reported-by: huangwen <huangwen@venustech.com.cn>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:21 +01:00
Alistair Strachan
1ea04ca97a media: uvcvideo: Fix 'type' check leading to overflow
commit 47bb117911 upstream.

When initially testing the Camera Terminal Descriptor wTerminalType
field (buffer[4]), no mask is used. Later in the function, the MSB is
overloaded to store the descriptor subtype, and so a mask of 0x7fff
is used to check the type.

If a descriptor is specially crafted to set this overloaded bit in the
original wTerminalType field, the initial type check will fail (falling
through, without adjusting the buffer size), but the later type checks
will pass, assuming the buffer has been made suitably large, causing an
overflow.

Avoid this problem by checking for the MSB in the wTerminalType field.
If the bit is set, assume the descriptor is bad, and abort parsing it.

Originally reported here:
https://groups.google.com/forum/#!topic/syzkaller/Ot1fOE6v1d8
A similar (non-compiling) patch was provided at that time.

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Alistair Strachan <astrachan@google.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:20 +01:00
Ben Hutchings
ae24fbd87a binder: Replace "%p" with "%pK" for stable
This was done as part of upstream commits fdfb4a99b6 "8inder:
separate binder allocator structure from binder proc", 19c987241c
"binder: separate out binder_alloc functions", and 7a4408c6bd
"binder: make sure accesses to proc/thread are safe".  However, those
commits made lots of other changes that are not suitable for stable.

Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:20 +01:00
Kirill Smelkov
6d654f9d5d fuse: Add FOPEN_STREAM to use stream_open()
commit bbd84f3365 upstream.

Starting from commit 9c225f2655 ("vfs: atomic f_pos accesses as per
POSIX") files opened even via nonseekable_open gate read and write via lock
and do not allow them to be run simultaneously. This can create read vs
write deadlock if a filesystem is trying to implement a socket-like file
which is intended to be simultaneously used for both read and write from
filesystem client.  See commit 10dce8af34 ("fs: stream_open - opener for
stream-like files so that read and write can run simultaneously without
deadlock") for details and e.g. commit 581d21a2d0 ("xenbus: fix deadlock
on writes to /proc/xen/xenbus") for a similar deadlock example on
/proc/xen/xenbus.

To avoid such deadlock it was tempting to adjust fuse_finish_open to use
stream_open instead of nonseekable_open on just FOPEN_NONSEEKABLE flags,
but grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE,
and in particular GVFS which actually uses offset in its read and write
handlers

	https://codesearch.debian.net/search?q=-%3Enonseekable+%3D
	https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080
	https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346
	https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481

so if we would do such a change it will break a real user.

Add another flag (FOPEN_STREAM) for filesystem servers to indicate that the
opened handler is having stream-like semantics; does not use file position
and thus the kernel is free to issue simultaneous read and write request on
opened file handle.

This patch together with stream_open() should be added to stable kernels
starting from v3.14+. This will allow to patch OSSPD and other FUSE
filesystems that provide stream-like files to return FOPEN_STREAM |
FOPEN_NONSEEKABLE in open handler and this way avoid the deadlock on all
kernel versions. This should work because fuse_finish_open ignores unknown
open flags returned from a filesystem and so passing FOPEN_STREAM to a
kernel that is not aware of this flag cannot hurt. In turn the kernel that
is not aware of FOPEN_STREAM will be < v3.14 where just FOPEN_NONSEEKABLE
is sufficient to implement streams without read vs write deadlock.

Cc: stable@vger.kernel.org # v3.14+
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:19 +01:00
Kirill Smelkov
f337ef0ad9 fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock
commit 10dce8af34 upstream.

[ while porting to 3.16 xenbus conflict was trivially resolved in a way
  that actually fixes /proc/xen/xenbus deadlock introduced in 3.14,
  because original upstream commit 581d21a2d0 to fix xenbus deadlock
  was not included into 3.16 . ]

Commit 9c225f2655 ("vfs: atomic f_pos accesses as per POSIX") added
locking for file.f_pos access and in particular made concurrent read and
write not possible - now both those functions take f_pos lock for the
whole run, and so if e.g. a read is blocked waiting for data, write will
deadlock waiting for that read to complete.

This caused regression for stream-like files where previously read and
write could run simultaneously, but after that patch could not do so
anymore. See e.g. commit 581d21a2d0 ("xenbus: fix deadlock on writes
to /proc/xen/xenbus") which fixes such regression for particular case of
/proc/xen/xenbus.

The patch that added f_pos lock in 2014 did so to guarantee POSIX thread
safety for read/write/lseek and added the locking to file descriptors of
all regular files. In 2014 that thread-safety problem was not new as it
was already discussed earlier in 2006.

However even though 2006'th version of Linus's patch was adding f_pos
locking "only for files that are marked seekable with FMODE_LSEEK (thus
avoiding the stream-like objects like pipes and sockets)", the 2014
version - the one that actually made it into the tree as 9c225f2655 -
is doing so irregardless of whether a file is seekable or not.

See

    https://lore.kernel.org/lkml/53022DB1.4070805@gmail.com/
    https://lwn.net/Articles/180387
    https://lwn.net/Articles/180396

for historic context.

The reason that it did so is, probably, that there are many files that
are marked non-seekable, but e.g. their read implementation actually
depends on knowing current position to correctly handle the read. Some
examples:

	kernel/power/user.c		snapshot_read
	fs/debugfs/file.c		u32_array_read
	fs/fuse/control.c		fuse_conn_waiting_read + ...
	drivers/hwmon/asus_atk0110.c	atk_debugfs_ggrp_read
	arch/s390/hypfs/inode.c		hypfs_read_iter
	...

Despite that, many nonseekable_open users implement read and write with
pure stream semantics - they don't depend on passed ppos at all. And for
those cases where read could wait for something inside, it creates a
situation similar to xenbus - the write could be never made to go until
read is done, and read is waiting for some, potentially external, event,
for potentially unbounded time -> deadlock.

Besides xenbus, there are 14 such places in the kernel that I've found
with semantic patch (see below):

	drivers/xen/evtchn.c:667:8-24: ERROR: evtchn_fops: .read() can deadlock .write()
	drivers/isdn/capi/capi.c:963:8-24: ERROR: capi_fops: .read() can deadlock .write()
	drivers/input/evdev.c:527:1-17: ERROR: evdev_fops: .read() can deadlock .write()
	drivers/char/pcmcia/cm4000_cs.c:1685:7-23: ERROR: cm4000_fops: .read() can deadlock .write()
	net/rfkill/core.c:1146:8-24: ERROR: rfkill_fops: .read() can deadlock .write()
	drivers/s390/char/fs3270.c:488:1-17: ERROR: fs3270_fops: .read() can deadlock .write()
	drivers/usb/misc/ldusb.c:310:1-17: ERROR: ld_usb_fops: .read() can deadlock .write()
	drivers/hid/uhid.c:635:1-17: ERROR: uhid_fops: .read() can deadlock .write()
	net/batman-adv/icmp_socket.c:80:1-17: ERROR: batadv_fops: .read() can deadlock .write()
	drivers/media/rc/lirc_dev.c:198:1-17: ERROR: lirc_fops: .read() can deadlock .write()
	drivers/leds/uleds.c:77:1-17: ERROR: uleds_fops: .read() can deadlock .write()
	drivers/input/misc/uinput.c:400:1-17: ERROR: uinput_fops: .read() can deadlock .write()
	drivers/infiniband/core/user_mad.c:985:7-23: ERROR: umad_fops: .read() can deadlock .write()
	drivers/gnss/core.c:45:1-17: ERROR: gnss_fops: .read() can deadlock .write()

In addition to the cases above another regression caused by f_pos
locking is that now FUSE filesystems that implement open with
FOPEN_NONSEEKABLE flag, can no longer implement bidirectional
stream-like files - for the same reason as above e.g. read can deadlock
write locking on file.f_pos in the kernel.

FUSE's FOPEN_NONSEEKABLE was added in 2008 in a7c1b990f7 ("fuse:
implement nonseekable open") to support OSSPD. OSSPD implements /dev/dsp
in userspace with FOPEN_NONSEEKABLE flag, with corresponding read and
write routines not depending on current position at all, and with both
read and write being potentially blocking operations:

See

    https://github.com/libfuse/osspd
    https://lwn.net/Articles/308445

    14a9cff0/osspd.c (L1406)
    14a9cff0/osspd.c (L1438-L1477)
    14a9cff0/osspd.c (L1479-L1510)

Corresponding libfuse example/test also describes FOPEN_NONSEEKABLE as
"somewhat pipe-like files ..." with read handler not using offset.
However that test implements only read without write and cannot exercise
the deadlock scenario:

    https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L124-L131
    https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L146-L163
    https://github.com/libfuse/libfuse/blob/fuse-3.4.2-3-ga1bff7d/example/poll.c#L209-L216

I've actually hit the read vs write deadlock for real while implementing
my FUSE filesystem where there is /head/watch file, for which open
creates separate bidirectional socket-like stream in between filesystem
and its user with both read and write being later performed
simultaneously. And there it is semantically not easy to split the
stream into two separate read-only and write-only channels:

    f13aa600/wcfs/wcfs.go (L88-169)

Let's fix this regression. The plan is:

1. We can't change nonseekable_open to include &~FMODE_ATOMIC_POS -
   doing so would break many in-kernel nonseekable_open users which
   actually use ppos in read/write handlers.

2. Add stream_open() to kernel to open stream-like non-seekable file
   descriptors. Read and write on such file descriptors would never use
   nor change ppos. And with that property on stream-like files read and
   write will be running without taking f_pos lock - i.e. read and write
   could be running simultaneously.

3. With semantic patch search and convert to stream_open all in-kernel
   nonseekable_open users for which read and write actually do not
   depend on ppos and where there is no other methods in file_operations
   which assume @offset access.

4. Add FOPEN_STREAM to fs/fuse/ and open in-kernel file-descriptors via
   steam_open if that bit is present in filesystem open reply.

   It was tempting to change fs/fuse/ open handler to use stream_open
   instead of nonseekable_open on just FOPEN_NONSEEKABLE flags, but
   grepping through Debian codesearch shows users of FOPEN_NONSEEKABLE,
   and in particular GVFS which actually uses offset in its read and
   write handlers

	https://codesearch.debian.net/search?q=-%3Enonseekable+%3D
	https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1080
	https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1247-1346
	https://gitlab.gnome.org/GNOME/gvfs/blob/1.40.0-6-gcbc54396/client/gvfsfusedaemon.c#L1399-1481

   so if we would do such a change it will break a real user.

5. Add stream_open and FOPEN_STREAM handling to stable kernels starting
   from v3.14+ (the kernel where 9c225f2655 first appeared).

   This will allow to patch OSSPD and other FUSE filesystems that
   provide stream-like files to return FOPEN_STREAM | FOPEN_NONSEEKABLE
   in their open handler and this way avoid the deadlock on all kernel
   versions. This should work because fs/fuse/ ignores unknown open
   flags returned from a filesystem and so passing FOPEN_STREAM to a
   kernel that is not aware of this flag cannot hurt. In turn the kernel
   that is not aware of FOPEN_STREAM will be < v3.14 where just
   FOPEN_NONSEEKABLE is sufficient to implement streams without read vs
   write deadlock.

This patch adds stream_open, converts /proc/xen/xenbus to it and adds
semantic patch to automatically locate in-kernel places that are either
required to be converted due to read vs write deadlock, or that are just
safe to be converted because read and write do not use ppos and there
are no other funky methods in file_operations.

Regarding semantic patch I've verified each generated change manually -
that it is correct to convert - and each other nonseekable_open instance
left - that it is either not correct to convert there, or that it is not
converted due to current stream_open.cocci limitations.

The script also does not convert files that should be valid to convert,
but that currently have .llseek = noop_llseek or generic_file_llseek for
unknown reason despite file being opened with nonseekable_open (e.g.
drivers/input/mousedev.c)

Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yongzhi Pan <panyongzhi@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Tejun Heo <tj@kernel.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Nikolaus Rath <Nikolaus@rath.org>
Cc: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ backport to 3.16: actually fixed deadlock on /proc/xen/xenbus as 581d21a2d0 was not backported to 3.16 ]
Signed-off-by: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:19 +01:00
Eric Dumazet
edb0a012ad tcp: refine memory limit test in tcp_fragment()
commit b6653b3629 upstream.

tcp_fragment() might be called for skbs in the write queue.

Memory limits might have been exceeded because tcp_sendmsg() only
checks limits at full skb (64KB) boundaries.

Therefore, we need to make sure tcp_fragment() wont punish applications
that might have setup very low SO_SNDBUF values.

Fixes: f070ef2ac6 ("tcp: tcp_fragment() should apply sane memory limits")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Christoph Paasch <cpaasch@apple.com>
Tested-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:18 +01:00
Xin Long
fd59cd035b pptp: dst_release sk_dst_cache in pptp_sock_destruct
commit 9417d81f4f upstream.

sk_setup_caps() is called to set sk->sk_dst_cache in pptp_connect,
so we have to dst_release(sk->sk_dst_cache) in pptp_sock_destruct,
otherwise, the dst refcnt will leak.

It can be reproduced by this syz log:

  r1 = socket$pptp(0x18, 0x1, 0x2)
  bind$pptp(r1, &(0x7f0000000100)={0x18, 0x2, {0x0, @local}}, 0x1e)
  connect$pptp(r1, &(0x7f0000000000)={0x18, 0x2, {0x3, @remote}}, 0x1e)

Consecutive dmesg warnings will occur:

  unregister_netdevice: waiting for lo to become free. Usage count = 1

v1->v2:
  - use rcu_dereference_protected() instead of rcu_dereference_check(),
    as suggested by Eric.

Fixes: 00959ade36 ("PPTP: PPP over IPv4 (Point-to-Point Tunneling Protocol)")
Reported-by: Xiumei Mu <xmu@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:18 +01:00
Eric Dumazet
0e96f139f6 l2tp: fix infoleak in l2tp_ip6_recvmsg()
commit 163d1c3d6f upstream.

Back in 2013 Hannes took care of most of such leaks in commit
bceaa90240 ("inet: prevent leakage of uninitialized memory to user in recv syscalls")

But the bug in l2tp_ip6_recvmsg() has not been fixed.

syzbot report :

BUG: KMSAN: kernel-infoleak in _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32
CPU: 1 PID: 10996 Comm: syz-executor362 Not tainted 5.0.0+ #11
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:600
 kmsan_internal_check_memory+0x9f4/0xb10 mm/kmsan/kmsan.c:694
 kmsan_copy_to_user+0xab/0xc0 mm/kmsan/kmsan_hooks.c:601
 _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32
 copy_to_user include/linux/uaccess.h:174 [inline]
 move_addr_to_user+0x311/0x570 net/socket.c:227
 ___sys_recvmsg+0xb65/0x1310 net/socket.c:2283
 do_recvmmsg+0x646/0x10c0 net/socket.c:2390
 __sys_recvmmsg net/socket.c:2469 [inline]
 __do_sys_recvmmsg net/socket.c:2492 [inline]
 __se_sys_recvmmsg+0x1d1/0x350 net/socket.c:2485
 __x64_sys_recvmmsg+0x62/0x80 net/socket.c:2485
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x445819
Code: e8 6c b6 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 2b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f64453eddb8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00000000006dac28 RCX: 0000000000445819
RDX: 0000000000000005 RSI: 0000000020002f80 RDI: 0000000000000003
RBP: 00000000006dac20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dac2c
R13: 00007ffeba8f87af R14: 00007f64453ee9c0 R15: 20c49ba5e353f7cf

Local variable description: ----addr@___sys_recvmsg
Variable was created at:
 ___sys_recvmsg+0xf6/0x1310 net/socket.c:2244
 do_recvmmsg+0x646/0x10c0 net/socket.c:2390

Bytes 0-31 of 32 are uninitialized
Memory access of size 32 starts at ffff8880ae62fbb0
Data copied to user address 0000000020000000

Fixes: a32e0eec70 ("l2tp: introduce L2TPv3 IP encapsulation support for IPv6")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.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>
2019-07-09 22:04:18 +01:00
Jack Morgenstein
c28e2bce64 net/mlx4_core: Fix qp mtt size calculation
commit 8511a653e9 upstream.

Calculation of qp mtt size (in function mlx4_RST2INIT_wrapper)
ultimately depends on function roundup_pow_of_two.

If the amount of memory required by the QP is less than one page,
roundup_pow_of_two is called with argument zero.  In this case, the
roundup_pow_of_two result is undefined.

Calling roundup_pow_of_two with a zero argument resulted in the
following stack trace:

UBSAN: Undefined behaviour in ./include/linux/log2.h:61:13
shift exponent 64 is too large for 64-bit type 'long unsigned int'
CPU: 4 PID: 26939 Comm: rping Tainted: G OE 4.19.0-rc1
Hardware name: Supermicro X9DR3-F/X9DR3-F, BIOS 3.2a 07/09/2015
Call Trace:
dump_stack+0x9a/0xeb
ubsan_epilogue+0x9/0x7c
__ubsan_handle_shift_out_of_bounds+0x254/0x29d
? __ubsan_handle_load_invalid_value+0x180/0x180
? debug_show_all_locks+0x310/0x310
? sched_clock+0x5/0x10
? sched_clock+0x5/0x10
? sched_clock_cpu+0x18/0x260
? find_held_lock+0x35/0x1e0
? mlx4_RST2INIT_QP_wrapper+0xfb1/0x1440 [mlx4_core]
mlx4_RST2INIT_QP_wrapper+0xfb1/0x1440 [mlx4_core]

Fix this by explicitly testing for zero, and returning one if the
argument is zero (assuming that the next higher power of 2 in this case
should be one).

Fixes: c82e9aa0a8 ("mlx4_core: resource tracking for HCA resources used by guests")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:17 +01:00
Jack Morgenstein
7a437ebe1c net/mlx4_core: Fix locking in SRIOV mode when switching between events and polling
commit c07d27927f upstream.

In procedures mlx4_cmd_use_events() and mlx4_cmd_use_polling(), we need to
guarantee that there are no FW commands in progress on the comm channel
(for VFs) or wrapped FW commands (on the PF) when SRIOV is active.

We do this by also taking the slave_cmd_mutex when SRIOV is active.

This is especially important when switching from event to polling, since we
free the command-context array during the switch.  If there are FW commands
in progress (e.g., waiting for a completion event), the completion event
handler will access freed memory.

Since the decision to use comm_wait or comm_poll is taken before grabbing
the event_sem/poll_sem in mlx4_comm_cmd_wait/poll, we must take the
slave_cmd_mutex as well (to guarantee that the decision to use events or
polling and the call to the appropriate cmd function are atomic).

Fixes: a7e1f04905 ("net/mlx4_core: Fix deadlock when switching between polling and event fw commands")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:17 +01:00
Kangjie Lu
1e70758c7e net: sh_eth: fix a missing check of of_get_phy_mode
commit 035a14e71f upstream.

of_get_phy_mode may fail and return a negative error code;
the fix checks the return value of of_get_phy_mode and
returns NULL of it fails.

Fixes: b356e978e9 ("sh_eth: add device tree support")
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Reviewed-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:17 +01:00
Aditya Pakki
0e355850c6 md: Fix failed allocation of md_register_thread
commit e406f12dde upstream.

mddev->sync_thread can be set to NULL on kzalloc failure downstream.
The patch checks for such a scenario and frees allocated resources.

Committer node:

Added similar fix to raid5.c, as suggested by Guoqing.

Acked-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:16 +01:00
Xiao Ni
6831d2d436 It's wrong to add len to sector_nr in raid10 reshape twice
commit b761dcf121 upstream.

In reshape_request it already adds len to sector_nr already. It's wrong to add len to
sector_nr again after adding pages to bio. If there is bad block it can't copy one chunk
at a time, it needs to goto read_more. Now the sector_nr is wrong. It can cause data
corruption.

Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:16 +01:00
Zev Weiss
7a8c67f3ff kernel/sysctl.c: add missing range check in do_proc_dointvec_minmax_conv
commit 8cf7630b29 upstream.

This bug has apparently existed since the introduction of this function
in the pre-git era (4500e91754d3 in Thomas Gleixner's history.git,
"[NET]: Add proc_dointvec_userhz_jiffies, use it for proper handling of
neighbour sysctls.").

As a minimal fix we can simply duplicate the corresponding check in
do_proc_dointvec_conv().

Link: http://lkml.kernel.org/r/20190207123426.9202-3-zev@bewilderbeest.net
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Luis Chamberlain <mcgrof@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>
2019-07-09 22:04:16 +01:00
Eric Dumazet
415f08eb36 gro_cells: make sure device is up in gro_cells_receive()
commit 2a5ff07a0e upstream.

We keep receiving syzbot reports [1] that show that tunnels do not play
the rcu/IFF_UP rules properly.

At device dismantle phase, gro_cells_destroy() will be called
only after a full rcu grace period is observed after IFF_UP
has been cleared.

This means that IFF_UP needs to be tested before queueing packets
into netif_rx() or gro_cells.

This patch implements the test in gro_cells_receive() because
too many callers do not seem to bother enough.

[1]
BUG: unable to handle kernel paging request at fffff4ca0b9ffffe
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 21 Comm: kworker/u4:1 Not tainted 5.0.0+ #97
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
RIP: 0010:__skb_unlink include/linux/skbuff.h:1929 [inline]
RIP: 0010:__skb_dequeue include/linux/skbuff.h:1945 [inline]
RIP: 0010:__skb_queue_purge include/linux/skbuff.h:2656 [inline]
RIP: 0010:gro_cells_destroy net/core/gro_cells.c:89 [inline]
RIP: 0010:gro_cells_destroy+0x19d/0x360 net/core/gro_cells.c:78
Code: 03 42 80 3c 20 00 0f 85 53 01 00 00 48 8d 7a 08 49 8b 47 08 49 c7 07 00 00 00 00 48 89 f9 49 c7 47 08 00 00 00 00 48 c1 e9 03 <42> 80 3c 21 00 0f 85 10 01 00 00 48 89 c1 48 89 42 08 48 c1 e9 03
RSP: 0018:ffff8880aa3f79a8 EFLAGS: 00010a02
RAX: 00ffffffffffffe8 RBX: ffffe8ffffc64b70 RCX: 1ffff8ca0b9ffffe
RDX: ffffc6505cffffe8 RSI: ffffffff858410ca RDI: ffffc6505cfffff0
RBP: ffff8880aa3f7a08 R08: ffff8880aa3e8580 R09: fffffbfff1263645
R10: fffffbfff1263644 R11: ffffffff8931b223 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffe8ffffc64b80 R15: ffffe8ffffc64b75
kobject: 'loop2' (000000004bd7d84a): kobject_uevent_env
FS:  0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffff4ca0b9ffffe CR3: 0000000094941000 CR4: 00000000001406f0
Call Trace:
kobject: 'loop2' (000000004bd7d84a): fill_kobj_path: path = '/devices/virtual/block/loop2'
 ip_tunnel_dev_free+0x19/0x60 net/ipv4/ip_tunnel.c:1010
 netdev_run_todo+0x51c/0x7d0 net/core/dev.c:8970
 rtnl_unlock+0xe/0x10 net/core/rtnetlink.c:116
 ip_tunnel_delete_nets+0x423/0x5f0 net/ipv4/ip_tunnel.c:1124
 vti_exit_batch_net+0x23/0x30 net/ipv4/ip_vti.c:495
 ops_exit_list.isra.0+0x105/0x160 net/core/net_namespace.c:156
 cleanup_net+0x3fb/0x960 net/core/net_namespace.c:551
 process_one_work+0x98e/0x1790 kernel/workqueue.c:2173
 worker_thread+0x98/0xe40 kernel/workqueue.c:2319
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Modules linked in:
CR2: fffff4ca0b9ffffe
   [ end trace 513fc9c1338d1cb3 ]
RIP: 0010:__skb_unlink include/linux/skbuff.h:1929 [inline]
RIP: 0010:__skb_dequeue include/linux/skbuff.h:1945 [inline]
RIP: 0010:__skb_queue_purge include/linux/skbuff.h:2656 [inline]
RIP: 0010:gro_cells_destroy net/core/gro_cells.c:89 [inline]
RIP: 0010:gro_cells_destroy+0x19d/0x360 net/core/gro_cells.c:78
Code: 03 42 80 3c 20 00 0f 85 53 01 00 00 48 8d 7a 08 49 8b 47 08 49 c7 07 00 00 00 00 48 89 f9 49 c7 47 08 00 00 00 00 48 c1 e9 03 <42> 80 3c 21 00 0f 85 10 01 00 00 48 89 c1 48 89 42 08 48 c1 e9 03
RSP: 0018:ffff8880aa3f79a8 EFLAGS: 00010a02
RAX: 00ffffffffffffe8 RBX: ffffe8ffffc64b70 RCX: 1ffff8ca0b9ffffe
RDX: ffffc6505cffffe8 RSI: ffffffff858410ca RDI: ffffc6505cfffff0
RBP: ffff8880aa3f7a08 R08: ffff8880aa3e8580 R09: fffffbfff1263645
R10: fffffbfff1263644 R11: ffffffff8931b223 R12: dffffc0000000000
kobject: 'loop3' (00000000e4ee57a6): kobject_uevent_env
R13: 0000000000000000 R14: ffffe8ffffc64b80 R15: ffffe8ffffc64b75
FS:  0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffff4ca0b9ffffe CR3: 0000000094941000 CR4: 00000000001406f0

Fixes: c9e6bc644e ("net: add gro_cells infrastructure")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16:
 - Adjust filename, context
 - Return type is void]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:15 +01:00
Eric Dumazet
b856c17659 vxlan: test dev->flags & IFF_UP before calling gro_cells_receive()
commit 59cbf56fcd upstream.

Same reasons than the ones explained in commit 4179cb5a4c
("vxlan: test dev->flags & IFF_UP before calling netif_rx()")

netif_rx() or gro_cells_receive() must be called under a strict contract.

At device dismantle phase, core networking clears IFF_UP
and flush_all_backlogs() is called after rcu grace period
to make sure no incoming packet might be in a cpu backlog
and still referencing the device.

A similar protocol is used for gro_cells infrastructure, as
gro_cells_destroy() will be called only after a full rcu
grace period is observed after IFF_UP has been cleared.

Most drivers call netif_rx() from their interrupt handler,
and since the interrupts are disabled at device dismantle,
netif_rx() does not have to check dev->flags & IFF_UP

Virtual drivers do not have this guarantee, and must
therefore make the check themselves.

Otherwise we risk use-after-free and/or crashes.

Fixes: d342894c5d ("vxlan: virtual extensible lan")
Signed-off-by: Eric Dumazet <edumazet@google.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>
2019-07-09 22:04:15 +01:00
Xin Long
0bab330e75 route: set the deleted fnhe fnhe_daddr to 0 in ip_del_fnhe to fix a race
commit ee60ad219f upstream.

The race occurs in __mkroute_output() when 2 threads lookup a dst:

  CPU A                 CPU B
  find_exception()
                        find_exception() [fnhe expires]
                        ip_del_fnhe() [fnhe is deleted]
  rt_bind_exception()

In rt_bind_exception() it will bind a deleted fnhe with the new dst, and
this dst will get no chance to be freed. It causes a dev defcnt leak and
consecutive dmesg warnings:

  unregister_netdevice: waiting for ethX to become free. Usage count = 1

Especially thanks Jon to identify the issue.

This patch fixes it by setting fnhe_daddr to 0 in ip_del_fnhe() to stop
binding the deleted fnhe with a new dst when checking fnhe's fnhe_daddr
and daddr in rt_bind_exception().

It works as both ip_del_fnhe() and rt_bind_exception() are protected by
fnhe_lock and the fhne is freed by kfree_rcu().

Fixes: deed49df73 ("route: check and remove route cache when we get route")
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:15 +01:00
Dan Carpenter
c6811c2317 xen, cpu_hotplug: Prevent an out of bounds access
commit 201676095d upstream.

The "cpu" variable comes from the sscanf() so Smatch marks it as
untrusted data.  We can't pass a higher value than "nr_cpu_ids" to
cpu_possible() or it results in an out of bounds access.

Fixes: d68d82afd4 ("xen: implement CPU hotplugging")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:14 +01:00
Stanislaw Gruszka
c70d1929aa lib/div64.c: off by one in shift
commit cdc94a3749 upstream.

fls counts bits starting from 1 to 32 (returns 0 for zero argument).  If
we add 1 we shift right one bit more and loose precision from divisor,
what cause function incorect results with some numbers.

Corrected code was tested in user-space, see bugzilla:
   https://bugzilla.kernel.org/show_bug.cgi?id=202391

Link: http://lkml.kernel.org/r/1548686944-11891-1-git-send-email-sgruszka@redhat.com
Fixes: 658716d19f ("div64_u64(): improve precision on 32bit platforms")
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Reported-by: Siarhei Volkau <lis8215@gmail.com>
Tested-by: Siarhei Volkau <lis8215@gmail.com>
Acked-by: Oleg Nesterov <oleg@redhat.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>
2019-07-09 22:04:14 +01:00
Arnd Bergmann
d7ee7a3fcf cpufreq: pxa2xx: remove incorrect __init annotation
commit 9505b98ccd upstream.

pxa_cpufreq_init_voltages() is marked __init but usually inlined into
the non-__init pxa_cpufreq_init() function. When building with clang,
it can stay as a standalone function in a discarded section, and produce
this warning:

WARNING: vmlinux.o(.text+0x616a00): Section mismatch in reference from the function pxa_cpufreq_init() to the function .init.text:pxa_cpufreq_init_voltages()
The function pxa_cpufreq_init() references
the function __init pxa_cpufreq_init_voltages().
This is often because pxa_cpufreq_init lacks a __init
annotation or the annotation of pxa_cpufreq_init_voltages is wrong.

Fixes: 50e77fcd79 ("ARM: pxa: remove __init from cpufreq_driver->init()")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:14 +01:00
Eric Dumazet
bc736b1a34 net/hsr: fix possible crash in add_timer()
commit 1e027960ed upstream.

syzbot found another add_timer() issue, this time in net/hsr [1]

Let's use mod_timer() which is safe.

[1]
kernel BUG at kernel/time/timer.c:1136!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 15909 Comm: syz-executor.3 Not tainted 5.0.0+ #97
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
kobject: 'loop2' (00000000f5629718): kobject_uevent_env
RIP: 0010:add_timer kernel/time/timer.c:1136 [inline]
RIP: 0010:add_timer+0x654/0xbe0 kernel/time/timer.c:1134
Code: 0f 94 c5 31 ff 44 89 ee e8 09 61 0f 00 45 84 ed 0f 84 77 fd ff ff e8 bb 5f 0f 00 e8 07 10 a0 ff e9 68 fd ff ff e8 ac 5f 0f 00 <0f> 0b e8 a5 5f 0f 00 0f 0b e8 9e 5f 0f 00 4c 89 b5 58 ff ff ff e9
RSP: 0018:ffff8880656eeca0 EFLAGS: 00010246
kobject: 'loop2' (00000000f5629718): fill_kobj_path: path = '/devices/virtual/block/loop2'
RAX: 0000000000040000 RBX: 1ffff1100caddd9a RCX: ffffc9000c436000
RDX: 0000000000040000 RSI: ffffffff816056c4 RDI: ffff88806a2f6cc8
RBP: ffff8880656eed58 R08: ffff888067f4a300 R09: ffff888067f4abc8
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88806a2f6cc0
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880656eed30
FS:  00007fc2019bf700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000738000 CR3: 0000000067e8e000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 hsr_check_announce net/hsr/hsr_device.c:99 [inline]
 hsr_check_carrier_and_operstate+0x567/0x6f0 net/hsr/hsr_device.c:120
 hsr_netdev_notify+0x297/0xa00 net/hsr/hsr_main.c:51
 notifier_call_chain+0xc7/0x240 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1739
 call_netdevice_notifiers_extack net/core/dev.c:1751 [inline]
 call_netdevice_notifiers net/core/dev.c:1765 [inline]
 dev_open net/core/dev.c:1436 [inline]
 dev_open+0x143/0x160 net/core/dev.c:1424
 team_port_add drivers/net/team/team.c:1203 [inline]
 team_add_slave+0xa07/0x15d0 drivers/net/team/team.c:1933
 do_set_master net/core/rtnetlink.c:2358 [inline]
 do_set_master+0x1d4/0x230 net/core/rtnetlink.c:2332
 do_setlink+0x966/0x3510 net/core/rtnetlink.c:2493
 rtnl_setlink+0x271/0x3b0 net/core/rtnetlink.c:2747
 rtnetlink_rcv_msg+0x465/0xb00 net/core/rtnetlink.c:5192
 netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2485
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5210
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1925
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:632
 sock_write_iter+0x27c/0x3e0 net/socket.c:923
 call_write_iter include/linux/fs.h:1869 [inline]
 do_iter_readv_writev+0x5e0/0x8e0 fs/read_write.c:680
 do_iter_write fs/read_write.c:956 [inline]
 do_iter_write+0x184/0x610 fs/read_write.c:937
 vfs_writev+0x1b3/0x2f0 fs/read_write.c:1001
 do_writev+0xf6/0x290 fs/read_write.c:1036
 __do_sys_writev fs/read_write.c:1109 [inline]
 __se_sys_writev fs/read_write.c:1106 [inline]
 __x64_sys_writev+0x75/0xb0 fs/read_write.c:1106
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457f29
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fc2019bec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457f29
RDX: 0000000000000001 RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc2019bf6d4
R13: 00000000004c4a60 R14: 00000000004dd218 R15: 00000000ffffffff

Fixes: f421436a59 ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Arvid Brodin <arvid.brodin@alten.se>
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>
2019-07-09 22:04:13 +01:00
Felipe Franciosi
15ae3ceed0 scsi: virtio_scsi: don't send sc payload with tmfs
commit 3722e6a521 upstream.

The virtio scsi spec defines struct virtio_scsi_ctrl_tmf as a set of
device-readable records and a single device-writable response entry:

    struct virtio_scsi_ctrl_tmf
    {
        // Device-readable part
        le32 type;
        le32 subtype;
        u8 lun[8];
        le64 id;
        // Device-writable part
        u8 response;
    }

The above should be organised as two descriptor entries (or potentially
more if using VIRTIO_F_ANY_LAYOUT), but without any extra data after "le64
id" or after "u8 response".

The Linux driver doesn't respect that, with virtscsi_abort() and
virtscsi_device_reset() setting cmd->sc before calling virtscsi_tmf().  It
results in the original scsi command payload (or writable buffers) added to
the tmf.

This fixes the problem by leaving cmd->sc zeroed out, which makes
virtscsi_kick_cmd() add the tmf to the control vq without any payload.

Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:13 +01:00
Halil Pasic
a707bc57cd s390/virtio: handle find on invalid queue gracefully
commit 3438b2c039 upstream.

A queue with a capacity of zero is clearly not a valid virtio queue.
Some emulators report zero queue size if queried with an invalid queue
index. Instead of crashing in this case let us just return -ENOENT. To
make that work properly, let us fix the notifier cleanup logic as well.

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:13 +01:00
Daniel Jordan
ff9465feaf mm, swap: bounds check swap_info array accesses to avoid NULL derefs
commit c10d38cc8d upstream.

Dan Carpenter reports a potential NULL dereference in
get_swap_page_of_type:

  Smatch complains that the NULL checks on "si" aren't consistent.  This
  seems like a real bug because we have not ensured that the type is
  valid and so "si" can be NULL.

Add the missing check for NULL, taking care to use a read barrier to
ensure CPU1 observes CPU0's updates in the correct order:

     CPU0                           CPU1
     alloc_swap_info()              if (type >= nr_swapfiles)
       swap_info[type] = p              /* handle invalid entry */
       smp_wmb()                    smp_rmb()
       ++nr_swapfiles               p = swap_info[type]

Without smp_rmb, CPU1 might observe CPU0's write to nr_swapfiles before
CPU0's write to swap_info[type] and read NULL from swap_info[type].

Ying Huang noticed other places in swapfile.c don't order these reads
properly.  Introduce swap_type_to_swap_info to encourage correct usage.

Use READ_ONCE and WRITE_ONCE to follow the Linux Kernel Memory Model
(see tools/memory-model/Documentation/explanation.txt).

This ordering need not be enforced in places where swap_lock is held
(e.g.  si_swapinfo) because swap_lock serializes updates to nr_swapfiles
and the swap_info array.

Link: http://lkml.kernel.org/r/20190131024410.29859-1-daniel.m.jordan@oracle.com
Fixes: ec8acf20af ("swap: add per-partition lock for swapfile")
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Suggested-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Tejun Heo <tj@kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[bwh: Backported to 3.16:
 - Add swp_swap_info(), as done in upstream commit 0bcac06f27
   "mm, swap: skip swapcache for swapin of synchronous device"
 - Use ACCESS_ONCE() instead of {READ,WRITE}_ONCE()
 - Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:13 +01:00
Hugh Dickins
24c6b38285 mm: fix potential data race in SyS_swapon
commit 6f179af88f upstream.

While running KernelThreadSanitizer (ktsan) on upstream kernel with
trinity, we got a few reports from SyS_swapon, here is one of them:

Read of size 8 by thread T307 (K7621):
 [<     inlined    >] SyS_swapon+0x3c0/0x1850 SYSC_swapon mm/swapfile.c:2395
 [<ffffffff812242c0>] SyS_swapon+0x3c0/0x1850 mm/swapfile.c:2345
 [<ffffffff81e97c8a>] ia32_do_call+0x1b/0x25

Looks like the swap_lock should be taken when iterating through the
swap_info array on lines 2392 - 2401: q->swap_file may be reset to
NULL by another thread before it is dereferenced for f_mapping.

But why is that iteration needed at all?  Doesn't the claim_swapfile()
which follows do all that is needed to check for a duplicate entry -
FMODE_EXCL on a bdev, testing IS_SWAPFILE under i_mutex on a regfile?

Well, not quite: bd_may_claim() allows the same "holder" to claim the
bdev again, so we do need to use a different holder than "sys_swapon";
and we should not replace appropriate -EBUSY by inappropriate -EINVAL.

Index i was reused in a cpu loop further down: renamed cpu there.

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:12 +01:00
Roman Penyaev
c2bf7c6315 mm/vmalloc: fix size check for remap_vmalloc_range_partial()
commit 401592d2e0 upstream.

When VM_NO_GUARD is not set area->size includes adjacent guard page,
thus for correct size checking get_vm_area_size() should be used, but
not area->size.

This fixes possible kernel oops when userspace tries to mmap an area on
1 page bigger than was allocated by vmalloc_user() call: the size check
inside remap_vmalloc_range_partial() accounts non-existing guard page
also, so check successfully passes but vmalloc_to_page() returns NULL
(guard page does not physically exist).

The following code pattern example should trigger an oops:

  static int oops_mmap(struct file *file, struct vm_area_struct *vma)
  {
        void *mem;

        mem = vmalloc_user(4096);
        BUG_ON(!mem);
        /* Do not care about mem leak */

        return remap_vmalloc_range(vma, mem, 0);
  }

And userspace simply mmaps size + PAGE_SIZE:

  mmap(NULL, 8192, PROT_WRITE|PROT_READ, MAP_PRIVATE, fd, 0);

Possible candidates for oops which do not have any explicit size
checks:

   *** drivers/media/usb/stkwebcam/stk-webcam.c:
   v4l_stk_mmap[789]   ret = remap_vmalloc_range(vma, sbuf->buffer, 0);

Or the following one:

   *** drivers/video/fbdev/core/fbmem.c
   static int
   fb_mmap(struct file *file, struct vm_area_struct * vma)
        ...
        res = fb->fb_mmap(info, vma);

Where fb_mmap callback calls remap_vmalloc_range() directly without any
explicit checks:

   *** drivers/video/fbdev/vfb.c
   static int vfb_mmap(struct fb_info *info,
             struct vm_area_struct *vma)
   {
       return remap_vmalloc_range(vma, (void *)info->fix.smem_start, vma->vm_pgoff);
   }

Link: http://lkml.kernel.org/r/20190103145954.16942-2-rpenyaev@suse.de
Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Joe Perches <joe@perches.com>
Cc: "Luis R. Rodriguez" <mcgrof@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>
2019-07-09 22:04:12 +01:00
Pavel Shilovsky
edef98ab18 CIFS: Fix read after write for files with read caching
commit 6dfbd84684 upstream.

When we have a READ lease for a file and have just issued a write
operation to the server we need to purge the cache and set oplock/lease
level to NONE to avoid reading stale data. Currently we do that
only if a write operation succedeed thus not covering cases when
a request was sent to the server but a negative error code was
returned later for some other reasons (e.g. -EIOCBQUEUED or -EINTR).
Fix this by turning off caching regardless of the error code being
returned.

The patches fixes generic tests 075 and 112 from the xfs-tests.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:12 +01:00
NeilBrown
70fc1659eb nfsd: fix memory corruption caused by readdir
commit b602345da6 upstream.

If the result of an NFSv3 readdir{,plus} request results in the
"offset" on one entry having to be split across 2 pages, and is sized
so that the next directory entry doesn't fit in the requested size,
then memory corruption can happen.

When encode_entry() is called after encoding the last entry that fits,
it notices that ->offset and ->offset1 are set, and so stores the
offset value in the two pages as required.  It clears ->offset1 but
*does not* clear ->offset.

Normally this omission doesn't matter as encode_entry_baggage() will
be called, and will set ->offset to a suitable value (not on a page
boundary).
But in the case where cd->buflen < elen and nfserr_toosmall is
returned, ->offset is not reset.

This means that nfsd3proc_readdirplus will see ->offset with a value 4
bytes before the end of a page, and ->offset1 set to NULL.
It will try to write 8bytes to ->offset.
If we are lucky, the next page will be read-only, and the system will
  BUG: unable to handle kernel paging request at...

If we are unlucky, some innocent page will have the first 4 bytes
corrupted.

nfsd3proc_readdir() doesn't even check for ->offset1, it just blindly
writes 8 bytes to the offset wherever it is.

Fix this by clearing ->offset after it is used, and copying the
->offset handling code from nfsd3_proc_readdirplus into
nfsd3_proc_readdir.

(Note that the commit hash in the Fixes tag is from the 'history'
 tree - this bug predates git).

Fixes: 0b1d57cf7654 ("[PATCH] kNFSd: Fix nfs3 dentry encoding")
Fixes-URL: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=0b1d57cf7654
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:11 +01:00
Pavel Shilovsky
588fe29cf5 CIFS: Do not reset lease state to NONE on lease break
commit 7b9b9edb49 upstream.

Currently on lease break the client sets a caching level twice:
when oplock is detected and when oplock is processed. While the
1st attempt sets the level to the value provided by the server,
the 2nd one resets the level to None unconditionally.
This happens because the oplock/lease processing code was changed
to avoid races between page cache flushes and oplock breaks.
The commit c11f1df500 ("cifs: Wait for writebacks to complete
before attempting write.") fixed the races for oplocks but didn't
apply the same changes for leases resulting in overwriting the
server granted value to None. Fix this by properly processing
lease breaks.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
[bwh: Backported to 3.16: drop change in smb311_operations]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:11 +01:00
Ido Schimmel
98afbb3781 ip6mr: Do not call __IP6_INC_STATS() from preemptible context
commit 87c11f1ddb upstream.

Similar to commit 44f49dd8b5 ("ipmr: fix possible race resulting from
improper usage of IP_INC_STATS_BH() in preemptible context."), we cannot
assume preemption is disabled when incrementing the counter and
accessing a per-CPU variable.

Preemption can be enabled when we add a route in process context that
corresponds to packets stored in the unresolved queue, which are then
forwarded using this route [1].

Fix this by using IP6_INC_STATS() which takes care of disabling
preemption on architectures where it is needed.

[1]
[  157.451447] BUG: using __this_cpu_add() in preemptible [00000000] code: smcrouted/2314
[  157.460409] caller is ip6mr_forward2+0x73e/0x10e0
[  157.460434] CPU: 3 PID: 2314 Comm: smcrouted Not tainted 5.0.0-rc7-custom-03635-g22f2712113f1 #1336
[  157.460449] Hardware name: Mellanox Technologies Ltd. MSN2100-CB2FO/SA001017, BIOS 5.6.5 06/07/2016
[  157.460461] Call Trace:
[  157.460486]  dump_stack+0xf9/0x1be
[  157.460553]  check_preemption_disabled+0x1d6/0x200
[  157.460576]  ip6mr_forward2+0x73e/0x10e0
[  157.460705]  ip6_mr_forward+0x9a0/0x1510
[  157.460771]  ip6mr_mfc_add+0x16b3/0x1e00
[  157.461155]  ip6_mroute_setsockopt+0x3cb/0x13c0
[  157.461384]  do_ipv6_setsockopt.isra.8+0x348/0x4060
[  157.462013]  ipv6_setsockopt+0x90/0x110
[  157.462036]  rawv6_setsockopt+0x4a/0x120
[  157.462058]  __sys_setsockopt+0x16b/0x340
[  157.462198]  __x64_sys_setsockopt+0xbf/0x160
[  157.462220]  do_syscall_64+0x14d/0x610
[  157.462349]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: 0912ea38de ("[IPV6] MROUTE: Add stats in multicast routing module method ip6_mr_forward().")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-by: Amit Cohen <amitc@mellanox.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>
2019-07-09 22:04:11 +01:00
YueHaibing
3c169c57e6 net-sysfs: Fix mem leak in netdev_register_kobject
commit 895a5e96db upstream.

syzkaller report this:
BUG: memory leak
unreferenced object 0xffff88837a71a500 (size 256):
  comm "syz-executor.2", pid 9770, jiffies 4297825125 (age 17.843s)
  hex dump (first 32 bytes):
    00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00  .....N..........
    ff ff ff ff ff ff ff ff 20 c0 ef 86 ff ff ff ff  ........ .......
  backtrace:
    [<00000000db12624b>] netdev_register_kobject+0x124/0x2e0 net/core/net-sysfs.c:1751
    [<00000000dc49a994>] register_netdevice+0xcc1/0x1270 net/core/dev.c:8516
    [<00000000e5f3fea0>] tun_set_iff drivers/net/tun.c:2649 [inline]
    [<00000000e5f3fea0>] __tun_chr_ioctl+0x2218/0x3d20 drivers/net/tun.c:2883
    [<000000001b8ac127>] vfs_ioctl fs/ioctl.c:46 [inline]
    [<000000001b8ac127>] do_vfs_ioctl+0x1a5/0x10e0 fs/ioctl.c:690
    [<0000000079b269f8>] ksys_ioctl+0x89/0xa0 fs/ioctl.c:705
    [<00000000de649beb>] __do_sys_ioctl fs/ioctl.c:712 [inline]
    [<00000000de649beb>] __se_sys_ioctl fs/ioctl.c:710 [inline]
    [<00000000de649beb>] __x64_sys_ioctl+0x74/0xb0 fs/ioctl.c:710
    [<000000007ebded1e>] do_syscall_64+0xc8/0x580 arch/x86/entry/common.c:290
    [<00000000db315d36>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
    [<00000000115be9bb>] 0xffffffffffffffff

It should call kset_unregister to free 'dev->queues_kset'
in error path of register_queue_kobjects, otherwise will cause a mem leak.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: 1d24eb4815 ("xps: Transmit Packet Steering")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.16: net_device pointer is called "net", confusingly]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:10 +01:00
Christophe Leroy
66c4b551dc powerpc/32: Clear on-stack exception marker upon exception return
commit 9580b71b5a upstream.

Clear the on-stack STACK_FRAME_REGS_MARKER on exception exit in order
to avoid confusing stacktrace like the one below.

  Call Trace:
  [c0e9dca0] [c01c42a0] print_address_description+0x64/0x2bc (unreliable)
  [c0e9dcd0] [c01c4684] kasan_report+0xfc/0x180
  [c0e9dd10] [c0895130] memchr+0x24/0x74
  [c0e9dd30] [c00a9e38] msg_print_text+0x124/0x574
  [c0e9dde0] [c00ab710] console_unlock+0x114/0x4f8
  [c0e9de40] [c00adc60] vprintk_emit+0x188/0x1c4
  --- interrupt: c0e9df00 at 0x400f330
      LR = init_stack+0x1f00/0x2000
  [c0e9de80] [c00ae3c4] printk+0xa8/0xcc (unreliable)
  [c0e9df20] [c0c27e44] early_irq_init+0x38/0x108
  [c0e9df50] [c0c15434] start_kernel+0x310/0x488
  [c0e9dff0] [00003484] 0x3484

With this patch the trace becomes:

  Call Trace:
  [c0e9dca0] [c01c42c0] print_address_description+0x64/0x2bc (unreliable)
  [c0e9dcd0] [c01c46a4] kasan_report+0xfc/0x180
  [c0e9dd10] [c0895150] memchr+0x24/0x74
  [c0e9dd30] [c00a9e58] msg_print_text+0x124/0x574
  [c0e9dde0] [c00ab730] console_unlock+0x114/0x4f8
  [c0e9de40] [c00adc80] vprintk_emit+0x188/0x1c4
  [c0e9de80] [c00ae3e4] printk+0xa8/0xcc
  [c0e9df20] [c0c27e44] early_irq_init+0x38/0x108
  [c0e9df50] [c0c15434] start_kernel+0x310/0x488
  [c0e9dff0] [00003484] 0x3484

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:10 +01:00
Hou Tao
8463eed58e 9p: use inode->i_lock to protect i_size_write() under 32-bit
commit 5e3cc1ee14 upstream.

Use inode->i_lock to protect i_size_write(), else i_size_read() in
generic_fillattr() may loop infinitely in read_seqcount_begin() when
multiple processes invoke v9fs_vfs_getattr() or v9fs_vfs_getattr_dotl()
simultaneously under 32-bit SMP environment, and a soft lockup will be
triggered as show below:

  watchdog: BUG: soft lockup - CPU#5 stuck for 22s! [stat:2217]
  Modules linked in:
  CPU: 5 PID: 2217 Comm: stat Not tainted 5.0.0-rc1-00005-g7f702faf5a9e #4
  Hardware name: Generic DT based system
  PC is at generic_fillattr+0x104/0x108
  LR is at 0xec497f00
  pc : [<802b8898>]    lr : [<ec497f00>]    psr: 200c0013
  sp : ec497e20  ip : ed608030  fp : ec497e3c
  r10: 00000000  r9 : ec497f00  r8 : ed608030
  r7 : ec497ebc  r6 : ec497f00  r5 : ee5c1550  r4 : ee005780
  r3 : 0000052d  r2 : 00000000  r1 : ec497f00  r0 : ed608030
  Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
  Control: 10c5387d  Table: ac48006a  DAC: 00000051
  CPU: 5 PID: 2217 Comm: stat Not tainted 5.0.0-rc1-00005-g7f702faf5a9e #4
  Hardware name: Generic DT based system
  Backtrace:
  [<8010d974>] (dump_backtrace) from [<8010dc88>] (show_stack+0x20/0x24)
  [<8010dc68>] (show_stack) from [<80a1d194>] (dump_stack+0xb0/0xdc)
  [<80a1d0e4>] (dump_stack) from [<80109f34>] (show_regs+0x1c/0x20)
  [<80109f18>] (show_regs) from [<801d0a80>] (watchdog_timer_fn+0x280/0x2f8)
  [<801d0800>] (watchdog_timer_fn) from [<80198658>] (__hrtimer_run_queues+0x18c/0x380)
  [<801984cc>] (__hrtimer_run_queues) from [<80198e60>] (hrtimer_run_queues+0xb8/0xf0)
  [<80198da8>] (hrtimer_run_queues) from [<801973e8>] (run_local_timers+0x28/0x64)
  [<801973c0>] (run_local_timers) from [<80197460>] (update_process_times+0x3c/0x6c)
  [<80197424>] (update_process_times) from [<801ab2b8>] (tick_nohz_handler+0xe0/0x1bc)
  [<801ab1d8>] (tick_nohz_handler) from [<80843050>] (arch_timer_handler_virt+0x38/0x48)
  [<80843018>] (arch_timer_handler_virt) from [<80180a64>] (handle_percpu_devid_irq+0x8c/0x240)
  [<801809d8>] (handle_percpu_devid_irq) from [<8017ac20>] (generic_handle_irq+0x34/0x44)
  [<8017abec>] (generic_handle_irq) from [<8017b344>] (__handle_domain_irq+0x6c/0xc4)
  [<8017b2d8>] (__handle_domain_irq) from [<801022e0>] (gic_handle_irq+0x4c/0x88)
  [<80102294>] (gic_handle_irq) from [<80101a30>] (__irq_svc+0x70/0x98)
  [<802b8794>] (generic_fillattr) from [<8056b284>] (v9fs_vfs_getattr_dotl+0x74/0xa4)
  [<8056b210>] (v9fs_vfs_getattr_dotl) from [<802b8904>] (vfs_getattr_nosec+0x68/0x7c)
  [<802b889c>] (vfs_getattr_nosec) from [<802b895c>] (vfs_getattr+0x44/0x48)
  [<802b8918>] (vfs_getattr) from [<802b8a74>] (vfs_statx+0x9c/0xec)
  [<802b89d8>] (vfs_statx) from [<802b9428>] (sys_lstat64+0x48/0x78)
  [<802b93e0>] (sys_lstat64) from [<80101000>] (ret_fast_syscall+0x0/0x28)

[dominique.martinet@cea.fr: updated comment to not refer to a function
in another subsystem]
Link: http://lkml.kernel.org/r/20190124063514.8571-2-houtao1@huawei.com
Fixes: 7549ae3e81 ("9p: Use the i_size_[read, write]() macros instead of using inode->i_size directly.")
Reported-by: Xing Gaopeng <xingaopeng@huawei.com>
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:10 +01:00
Trond Myklebust
30771a3b62 NFSv4.1: Reinitialise sequence results before retransmitting a request
commit c1dffe0bf7 upstream.

If we have to retransmit a request, we should ensure that we reinitialise
the sequence results structure, since in the event of a signal
we need to treat the request as if it had not been sent.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:09 +01:00
Tony Jones
5b4f9ccfd4 tools lib traceevent: Fix buffer overflow in arg_eval
commit 7c5b019e3a upstream.

Fix buffer overflow observed when running perf test.

The overflow is when trying to evaluate "1ULL << (64 - 1)" which is
resulting in -9223372036854775808 which overflows the 20 character
buffer.

If is possible this bug has been reported before but I still don't see
any fix checked in:

See: https://www.spinics.net/lists/linux-perf-users/msg07714.html

Reported-by: Michael Sartain <mikesart@fastmail.com>
Reported-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Tony Jones <tonyj@suse.de>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Fixes: f7d82350e5 ("tools/events: Add files to create libtraceevent.a")
Link: http://lkml.kernel.org/r/20190228015532.8941-1-tonyj@suse.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:09 +01:00
Filipe Manana
3078ec66dc Btrfs: fix corruption reading shared and compressed extents after hole punching
commit 8e92821878 upstream.

In the past we had data corruption when reading compressed extents that
are shared within the same file and they are consecutive, this got fixed
by commit 005efedf2c ("Btrfs: fix read corruption of compressed and
shared extents") and by commit 808f80b467 ("Btrfs: update fix for read
corruption of compressed and shared extents"). However there was a case
that was missing in those fixes, which is when the shared and compressed
extents are referenced with a non-zero offset. The following shell script
creates a reproducer for this issue:

  #!/bin/bash

  mkfs.btrfs -f /dev/sdc &> /dev/null
  mount -o compress /dev/sdc /mnt/sdc

  # Create a file with 3 consecutive compressed extents, each has an
  # uncompressed size of 128Kb and a compressed size of 4Kb.
  for ((i = 1; i <= 3; i++)); do
      head -c 4096 /dev/zero
      for ((j = 1; j <= 31; j++)); do
          head -c 4096 /dev/zero | tr '\0' "\377"
      done
  done > /mnt/sdc/foobar
  sync

  echo "Digest after file creation:   $(md5sum /mnt/sdc/foobar)"

  # Clone the first extent into offsets 128K and 256K.
  xfs_io -c "reflink /mnt/sdc/foobar 0 128K 128K" /mnt/sdc/foobar
  xfs_io -c "reflink /mnt/sdc/foobar 0 256K 128K" /mnt/sdc/foobar
  sync

  echo "Digest after cloning:         $(md5sum /mnt/sdc/foobar)"

  # Punch holes into the regions that are already full of zeroes.
  xfs_io -c "fpunch 0 4K" /mnt/sdc/foobar
  xfs_io -c "fpunch 128K 4K" /mnt/sdc/foobar
  xfs_io -c "fpunch 256K 4K" /mnt/sdc/foobar
  sync

  echo "Digest after hole punching:   $(md5sum /mnt/sdc/foobar)"

  echo "Dropping page cache..."
  sysctl -q vm.drop_caches=1
  echo "Digest after hole punching:   $(md5sum /mnt/sdc/foobar)"

  umount /dev/sdc

When running the script we get the following output:

  Digest after file creation:   5a0888d80d7ab1fd31c229f83a3bbcc8  /mnt/sdc/foobar
  linked 131072/131072 bytes at offset 131072
  128 KiB, 1 ops; 0.0033 sec (36.960 MiB/sec and 295.6830 ops/sec)
  linked 131072/131072 bytes at offset 262144
  128 KiB, 1 ops; 0.0015 sec (78.567 MiB/sec and 628.5355 ops/sec)
  Digest after cloning:         5a0888d80d7ab1fd31c229f83a3bbcc8  /mnt/sdc/foobar
  Digest after hole punching:   5a0888d80d7ab1fd31c229f83a3bbcc8  /mnt/sdc/foobar
  Dropping page cache...
  Digest after hole punching:   fba694ae8664ed0c2e9ff8937e7f1484  /mnt/sdc/foobar

This happens because after reading all the pages of the extent in the
range from 128K to 256K for example, we read the hole at offset 256K
and then when reading the page at offset 260K we don't submit the
existing bio, which is responsible for filling all the page in the
range 128K to 256K only, therefore adding the pages from range 260K
to 384K to the existing bio and submitting it after iterating over the
entire range. Once the bio completes, the uncompressed data fills only
the pages in the range 128K to 256K because there's no more data read
from disk, leaving the pages in the range 260K to 384K unfilled. It is
just a slightly different variant of what was solved by commit
005efedf2c ("Btrfs: fix read corruption of compressed and shared
extents").

Fix this by forcing a bio submit, during readpages(), whenever we find a
compressed extent map for a page that is different from the extent map
for the previous page or has a different starting offset (in case it's
the same compressed extent), instead of the extent map's original start
offset.

A test case for fstests follows soon.

Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Fixes: 808f80b467 ("Btrfs: update fix for read corruption of compressed and shared extents")
Fixes: 005efedf2c ("Btrfs: fix read corruption of compressed and shared extents")
Tested-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:09 +01:00
Jordan Niethe
195f8ed183 powerpc/powernv: Make opal log only readable by root
commit 7b62f9bd22 upstream.

Currently the opal log is globally readable. It is kernel policy to
limit the visibility of physical addresses / kernel pointers to root.
Given this and the fact the opal log may contain this information it
would be better to limit the readability to root.

Fixes: bfc36894a4 ("powerpc/powernv: Add OPAL message log interface")
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Reviewed-by: Stewart Smith <stewart@linux.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:04:08 +01:00