[ Upstream commit 00f9fec4 ]

The error print within mlx4_flow_steer_promisc_add() should
be a info print.

Fixes: 592e49dd ('net/mlx4: Implement promiscuous mode with device managed flow-steering')
Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit d7c04b05 ]

When host is under high stress, it is very possible thread
running netdev_wait_allrefs() returns from msleep(250)
10 seconds late.

This leads to these messages in the syslog :

[...] unregister_netdevice: waiting for syz_tun to become free. Usage count = 0

If the device refcount is zero, the wait is over.
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 0fe9f173 ]

Jiri reported that with a kernel built with CONFIG_FIXED_PHY=y,
CONFIG_NET_DSA=m and CONFIG_NET_DSA_LOOP=m, we would not get to a
functional state where the mock-up driver is registered. Turns out that
we are not descending into drivers/net/dsa/ unconditionally, and we
won't be able to link-in dsa_loop_bdinfo.o which does the actual mock-up
mdio device registration.
Reported-by: Jiri Pirko <jiri@resnulli.us>
Fixes: 40013ff2 ("net: dsa: Fix functional dsa-loop dependency on FIXED_PHY")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Tested-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 61fb0d01 ]

At ipv6 route dismantle, fib6_drop_pcpu_from() is responsible
for finding all percpu routes and set their ->from pointer
to NULL, so that fib6_ref can reach its expected value (1).

The problem right now is that other cpus can still catch the
route being deleted, since there is no rcu grace period
between the route deletion and call to fib6_drop_pcpu_from()

This can leak the fib6 and associated resources, since no
notifier will take care of removing the last reference(s).

I decided to add another boolean (fib6_destroying) instead
of reusing/renaming exception_bucket_flushed to ease stable backports,
and properly document the memory barriers used to implement this fix.

This patch has been co-developped with Wei Wang.

Fixes: 93531c67 ("net/ipv6: separate handling of FIB entries from dst based routes")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Wei Wang <weiwan@google.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Martin Lau <kafai@fb.com>
Acked-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 510e2ced ]

When inserting route cache into the exception table, the key is
generated with both src_addr and dest_addr with src addr routing.
However, current logic always assumes the src_addr used to generate the
key is a /128 host address. This is not true in the following scenarios:
1. When the route is a gateway route or does not have next hop.
   (rt6_is_gw_or_nonexthop() == false)
2. When calling ip6_rt_cache_alloc(), saddr is passed in as NULL.
This means, when looking for a route cache in the exception table, we
have to do the lookup twice: first time with the passed in /128 host
address, second time with the src_addr stored in fib6_info.

This solves the pmtu discovery issue reported by Mikael Magnusson where
a route cache with a lower mtu info is created for a gateway route with
src addr. However, the lookup code is not able to find this route cache.

Fixes: 2b760fcf ("ipv6: hook up exception table to store dst cache")
Reported-by: Mikael Magnusson <mikael.kernel@lists.m7n.se>
Bisected-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Wei Wang <weiwan@google.com>
Cc: Martin Lau <kafai@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 1a42010c upstream.

Define the gup_fast_permitted to check against the asce_limit of the
mm attached to the current task, then replace the s390 specific gup
code with the generic implementation in mm/gup.c.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit d1874a0c upstream.

Change the way how pgd_offset, p4d_offset, pud_offset and pmd_offset
walk the page tables. pgd_offset now always calculates the index for
the top-level page table and adds it to the pgd, this is either a
segment table offset for a 2-level setup, a region-3 offset for 3-levels,
region-2 offset for 4-levels, or a region-1 offset for a 5-level setup.
The other three functions p4d_offset, pud_offset and pmd_offset will
only add the respective offset if they dereference the passed pointer.

With the new way of walking the page tables a sequence like this from
mm/gup.c now works:

     pgdp = pgd_offset(current->mm, addr);
     pgd = READ_ONCE(*pgdp);
     p4dp = p4d_offset(&pgd, addr);
     p4d = READ_ONCE(*p4dp);
     pudp = pud_offset(&p4d, addr);
     pud = READ_ONCE(*pudp);
     pmdp = pmd_offset(&pud, addr);
     pmd = READ_ONCE(*pmdp);
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit c4703ce1 upstream.

Users have reported intermittent occurrences of DIMM initialization
failures due to duplicate allocations of address capacity detected in
the labels, or errors of the form below, both have the same root cause.

    nd namespace1.4: failed to track label: 0
    WARNING: CPU: 17 PID: 1381 at drivers/nvdimm/label.c:863

    RIP: 0010:__pmem_label_update+0x56c/0x590 [libnvdimm]
    Call Trace:
     ? nd_pmem_namespace_label_update+0xd6/0x160 [libnvdimm]
     nd_pmem_namespace_label_update+0xd6/0x160 [libnvdimm]
     uuid_store+0x17e/0x190 [libnvdimm]
     kernfs_fop_write+0xf0/0x1a0
     vfs_write+0xb7/0x1b0
     ksys_write+0x57/0xd0
     do_syscall_64+0x60/0x210

Unfortunately those reports were typically with a busy parallel
namespace creation / destruction loop making it difficult to see the
components of the bug. However, Jane provided a simple reproducer using
the work-in-progress sub-section implementation.

When ndctl is reconfiguring a namespace it may take an existing defunct
/ disabled namespace and reconfigure it with a new uuid and other
parameters. Critically namespace_update_uuid() takes existing address
resources and renames them for the new namespace to use / reconfigure as
it sees fit. The bug is that this rename only happens in the resource
tracking tree. Existing labels with the old uuid are not reaped leading
to a scenario where multiple active labels reference the same span of
address range.

Teach namespace_update_uuid() to flag any references to the old uuid for
reaping at the next label update attempt.

Cc: <stable@vger.kernel.org>
Fixes: bf9bccc1 ("libnvdimm: pmem label sets and namespace instantiation")
Link: https://github.com/pmem/ndctl/issues/91Reported-by: Jane Chu <jane.chu@oracle.com>
Reported-by: Jeff Moyer <jmoyer@redhat.com>
Reported-by: Erwin Tsaur <erwin.tsaur@oracle.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 397d2300 upstream.

flush_hash_pages() runs with data translation off, so current
task_struct has to be accesssed using physical address.

Fixes: f7354cca ("powerpc/32: Remove CURRENT_THREAD_INFO and rename TI_CPU")
Cc: stable@vger.kernel.org # v5.1+
Reported-by: Erhard F. <erhard_f@mailbox.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 72813bfb upstream.

This involves initializing the boot params EFI related fields and the
efi global variable.

Without this fix a PVH dom0 doesn't detect when booted from EFI, and
thus doesn't support accessing any of the EFI related data.
Reported-by: PGNet Dev <pgnet.dev@gmail.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: stable@vger.kernel.org # 4.19+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit c9f804d6 upstream.

Or else xen_domain() returns false despite xen_pvh being set.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: stable@vger.kernel.org # 4.19+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit d2f8ae0e upstream.

syncconfig is responsible for keeping auto.conf up-to-date, so if it
fails for any reason, the build must be terminated immediately.

However, since commit 9390dff6 ("kbuild: invoke syncconfig if
include/config/auto.conf.cmd is missing"), Kbuild continues running
even after syncconfig fails.

You can confirm this by intentionally making syncconfig error out:

#  diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
#  index 08ba146..307b9de 100644
#  --- a/scripts/kconfig/confdata.c
#  +++ b/scripts/kconfig/confdata.c
#  @@ -1023,6 +1023,9 @@ int conf_write_autoconf(int overwrite)
#          FILE *out, *tristate, *out_h;
#          int i;
#
#  +       if (overwrite)
#  +               return 1;
#  +
#          if (!overwrite && is_present(autoconf_name))
#                  return 0;

Then, syncconfig fails, but Make would not stop:

  $ make -s mrproper allyesconfig defconfig
  $ make
  scripts/kconfig/conf  --syncconfig Kconfig

  *** Error during sync of the configuration.

  make[2]: *** [scripts/kconfig/Makefile;69: syncconfig] Error 1
  make[1]: *** [Makefile;557: syncconfig] Error 2
  make: *** [include/config/auto.conf.cmd] Deleting file 'include/config/tristate.conf'
  make: Failed to remake makefile 'include/config/auto.conf'.
    SYSTBL  arch/x86/include/generated/asm/syscalls_32.h
    SYSHDR  arch/x86/include/generated/asm/unistd_32_ia32.h
    SYSHDR  arch/x86/include/generated/asm/unistd_64_x32.h
    SYSTBL  arch/x86/include/generated/asm/syscalls_64.h
  [ continue running ... ]

The reason is in the behavior of a pattern rule with multi-targets.

  %/auto.conf %/auto.conf.cmd %/tristate.conf: $(KCONFIG_CONFIG)
          $(Q)$(MAKE) -f $(srctree)/Makefile syncconfig

GNU Make knows this rule is responsible for making all the three files
simultaneously. As far as examined, auto.conf.cmd is the target in
question when this rule is invoked. It is probably because auto.conf.cmd
is included below the inclusion of auto.conf.

The inclusion of auto.conf is mandatory, while that of auto.conf.cmd
is optional. GNU Make does not care about the failure in the process
of updating optional include files.

I filed this issue (https://savannah.gnu.org/bugs/?56301) in case this
behavior could be improved somehow in future releases of GNU Make.
Anyway, it is quite easy to fix our Makefile.

Given that auto.conf is already a mandatory include file, there is no
reason to stick auto.conf.cmd optional. Make it mandatory as well.

Cc: linux-stable <stable@vger.kernel.org> # 5.0+
Fixes: 9390dff6 ("kbuild: invoke syncconfig if include/config/auto.conf.cmd is missing")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
[commented out diff above to keep patch happy - gregkh]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit b63a9de0 upstream.

Displaying the session id in /proc/fs/cifs/DebugData
is needed in order to correlate Linux client information
with network and server traces for many common support
scenarios.  Turned out to be very important for debugging.
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit ee66e453 upstream.

...now that VMX's preemption timer, i.e. the hv_timer, also adjusts its
programmed time based on lapic_timer_advance_ns.  Without the delay, a
guest can see a timer interrupt arrive before the requested time when
KVM is using the hv_timer to emulate the guest's interrupt.

Fixes: c5ce8235 ("KVM: VMX: Optimize tscdeadline timer latency")
Cc: <stable@vger.kernel.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Reviewed-by: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 11988499 upstream.

KVM allows userspace to violate consistency checks related to the
guest's CPUID model to some degree.  Generally speaking, userspace has
carte blanche when it comes to guest state so long as jamming invalid
state won't negatively affect the host.

Currently this is seems to be a non-issue as most of the interesting
EFER checks are missing, e.g. NX and LME, but those will be added
shortly.  Proactively exempt userspace from the CPUID checks so as not
to break userspace.

Note, the efer_reserved_bits check still applies to userspace writes as
that mask reflects the host's capabilities, e.g. KVM shouldn't allow a
guest to run with NX=1 if it has been disabled in the host.

Fixes: d8017474 ("KVM: SVM: Only allow setting of EFER_SVME when CPUID SVM is set")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 4ddc9204 upstream.

kvm_dirty_bitmap_bytes() will return the size of the dirty bitmap of
the memslot rather than the size of bitmap passed over from the ioctl.
Here for KVM_CLEAR_DIRTY_LOG we should only copy exactly the size of
bitmap that covers kvm_clear_dirty_log.num_pages.
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 2a31b9dbSigned-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit f93f7ede upstream.

The RDPMC-exiting control is dependent on the existence of the RDPMC
instruction itself, i.e. is not tied to the "Architectural Performance
Monitoring" feature.  For all intents and purposes, the control exists
on all CPUs with VMX support since RDPMC also exists on all VCPUs with
VMX supported.  Per Intel's SDM:

  The RDPMC instruction was introduced into the IA-32 Architecture in
  the Pentium Pro processor and the Pentium processor with MMX technology.
  The earlier Pentium processors have performance-monitoring counters, but
  they must be read with the RDMSR instruction.

Because RDPMC-exiting always exists, KVM requires the control and refuses
to load if it's not available.  As a result, hiding the PMU from a guest
breaks nested virtualization if the guest attemts to use KVM.

While it's not explicitly stated in the RDPMC pseudocode, the VM-Exit
check for RDPMC-exiting follows standard fault vs. VM-Exit prioritization
for privileged instructions, e.g. occurs after the CPL/CR0.PE/CR4.PCE
checks, but before the counter referenced in ECX is checked for validity.

In other words, the original KVM behavior of injecting a #GP was correct,
and the KVM unit test needs to be adjusted accordingly, e.g. eat the #GP
when the unit test guest (L3 in this case) executes RDPMC without
RDPMC-exiting set in the unit test host (L2).

This reverts commit e51bfdb6.

Fixes: e51bfdb6 ("KVM: nVMX: Expose RDPMC-exiting only when guest supports PMU")
Reported-by: David Hill <hilld@binarystorm.net>
Cc: Saar Amar <saaramar@microsoft.com>
Cc: Mihai Carabas <mihai.carabas@oracle.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Liran Alon <liran.alon@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 0d52154b upstream.

When failing from creating cache jbd2_inode_cache, we will destroy the
previously created cache jbd2_handle_cache twice.  This patch fixes
this by moving each cache initialization/destruction to its own
separate, individual function.
Signed-off-by: Chengguang Xu <cgxu519@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 56df90b6 upstream.

Add patch for realtek codec in Lenovo B50-70 that fixes inverted
internal microphone channel.
Device IdeaPad Y410P has the same PCI SSID as Lenovo B50-70,
but first one is about fix the noise and it didn't seem help in a
later kernel version.
So I replaced IdeaPad Y410P device description with B50-70 and apply
inverted microphone fix.

Bugzilla: https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1524215Signed-off-by: Michał Wadowski <wadosm@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit dad3197d upstream.

Dell platform with ALC298.
system enter to runtime suspend. Headphone had noise.
Let Headset Mic not shutup will solve this issue.

[ Fixed minor coding style issues by tiwai ]
Signed-off-by: Kailang Yang <kailang@realtek.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 891afcf2 upstream.

A mistake was made in the identification of the four variants of the
System76 Gazelle (gaze14). This patch corrects the PCI ID of the
17-inch, GTX 1660 Ti variant from 0x8560 to 0x8551. This patch also
adds the correct fixups for the 15-inch and 17-inch GTX 1650 variants
with PCI IDs 0x8560 and 0x8561.

Tests were done on all four variants ensuring full audio capability.

Fixes: 80a5052d ("ALSA: hdea/realtek - Headset fixup for System76 Gazelle (gaze14)")
Signed-off-by: Jeremy Soller <jeremy@system76.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 2c1d0e36 upstream.

Handling of aborted journal is a special code path different from
standard ext4_error() one and it can call panic() as well. Commit
1dc1097f ("ext4: avoid panic during forced reboot") forgot to update
this path so fix that omission.

Fixes: 1dc1097f ("ext4: avoid panic during forced reboot")
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org # 5.1
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 08fc98a4 upstream.

The buffer_head (frames[0].bh) and it's corresping page can be
potentially free'd once brelse() is done inside the for loop
but before the for loop exits in dx_release(). It can be free'd
in another context, when the page cache is flushed via
drop_caches_sysctl_handler(). This results into below data abort
when accessing info->indirect_levels in dx_release().

Unable to handle kernel paging request at virtual address ffffffc17ac3e01e
Call trace:
 dx_release+0x70/0x90
 ext4_htree_fill_tree+0x2d4/0x300
 ext4_readdir+0x244/0x6f8
 iterate_dir+0xbc/0x160
 SyS_getdents64+0x94/0x174
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 57a0da28 upstream.

Unaligned AIO must be serialized because the zeroing of partial blocks
of unaligned AIO can result in data corruption in case it's overlapping
another in flight IO.

Currently we wait for all unwritten extents before we submit unaligned
AIO which protects data in case of unaligned AIO is following overlapping
IO. However if a unaligned AIO is followed by overlapping aligned AIO we
can still end up corrupting data.

To fix this, we must make sure that the unaligned AIO is the only IO in
flight by waiting for unwritten extents conversion not just before the
IO submission, but right after it as well.

This problem can be reproduced by xfstest generic/538
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 592acbf1 upstream.

This commit zeroes out the unused memory region in the buffer_head
corresponding to the extent metablock after writing the extent header
and the corresponding extent node entries.

This is done to prevent random uninitialized data from getting into
the filesystem when the extent block is synced.

This fixes CVE-2019-11833.
Signed-off-by: Sriram Rajagopalan <sriramr@arista.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit f91253a3 upstream.

The Linux kernel will auto-disables all boot consoles whenever it
gets a preferred real console.

Currently on RISC-V systems, if we have a real console which is not
RISCV SBI console then boot consoles (such as earlycon=sbi) are not
auto-disabled when a real console (ttyS0 or ttySIF0) is available.
This results in duplicate prints at boot-time after kernel starts
using real console (i.e. ttyS0 or ttySIF0) if "earlycon=" kernel
parameter was passed by bootloader.

The reason for above issue is that RISCV SBI console always adds
itself as preferred console which is causing other real consoles
to be not used as preferred console.

Ideally "console=" kernel parameter passed by bootloaders should
be the one selecting a preferred real console.

This patch fixes above issue by not forcing RISCV SBI console as
preferred console.

Fixes: afa6b1cc ("tty: New RISC-V SBI console driver")
Cc: stable@vger.kernel.org
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit ec084de9 upstream.

synchronize_rcu() didn't wait for call_rcu() callbacks, so inode wb
switch may not go to the workqueue after synchronize_rcu().  Thus
previous scheduled switches was not finished even flushing the
workqueue, which will cause a NULL pointer dereferenced followed below.

  VFS: Busy inodes after unmount of vdd. Self-destruct in 5 seconds.  Have a nice day...
  BUG: unable to handle kernel NULL pointer dereference at 0000000000000278
    evict+0xb3/0x180
    iput+0x1b0/0x230
    inode_switch_wbs_work_fn+0x3c0/0x6a0
    worker_thread+0x4e/0x490
    ? process_one_work+0x410/0x410
    kthread+0xe6/0x100
    ret_from_fork+0x39/0x50

Replace the synchronize_rcu() call with a rcu_barrier() to wait for all
pending callbacks to finish.  And inc isw_nr_in_flight after call_rcu()
in inode_switch_wbs() to make more sense.

Link: http://lkml.kernel.org/r/20190429024108.54150-1-jiufei.xue@linux.alibaba.comSigned-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com>
Acked-by: Tejun Heo <tj@kernel.org>
Suggested-by: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 60fce36a upstream.

syzbot reported the following error from a tree with a head commit of
baf76f0c ("slip: make slhc_free() silently accept an error pointer")

  BUG: unable to handle kernel paging request at ffffea0003348000
  #PF error: [normal kernel read fault]
  PGD 12c3f9067 P4D 12c3f9067 PUD 12c3f8067 PMD 0
  Oops: 0000 [#1] PREEMPT SMP KASAN
  CPU: 1 PID: 28916 Comm: syz-executor.2 Not tainted 5.1.0-rc6+ #89
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
  RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:314 [inline]
  RIP: 0010:PageCompound include/linux/page-flags.h:186 [inline]
  RIP: 0010:isolate_freepages_block+0x1c0/0xd40 mm/compaction.c:579
  Code: 01 d8 ff 4d 85 ed 0f 84 ef 07 00 00 e8 29 00 d8 ff 4c 89 e0 83 85 38 ff
  ff ff 01 48 c1 e8 03 42 80 3c 38 00 0f 85 31 0a 00 00 <4d> 8b 2c 24 31 ff 49
  c1 ed 10 41 83 e5 01 44 89 ee e8 3a 01 d8 ff
  RSP: 0018:ffff88802b31eab8 EFLAGS: 00010246
  RAX: 1ffffd4000669000 RBX: 00000000000cd200 RCX: ffffc9000a235000
  RDX: 000000000001ca5e RSI: ffffffff81988cc7 RDI: 0000000000000001
  RBP: ffff88802b31ebd8 R08: ffff88805af700c0 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000000 R12: ffffea0003348000
  R13: 0000000000000000 R14: ffff88802b31f030 R15: dffffc0000000000
  FS:  00007f61648dc700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: ffffea0003348000 CR3: 0000000037c64000 CR4: 00000000001426e0
  Call Trace:
   fast_isolate_around mm/compaction.c:1243 [inline]
   fast_isolate_freepages mm/compaction.c:1418 [inline]
   isolate_freepages mm/compaction.c:1438 [inline]
   compaction_alloc+0x1aee/0x22e0 mm/compaction.c:1550

There is no reproducer and it is difficult to hit -- 1 crash every few
days.  The issue is very similar to the fix in commit 6b0868c8
("mm/compaction.c: correct zone boundary handling when resetting pageblock
skip hints").  When isolating free pages around a target pageblock, the
boundary handling is off by one and can stray into the next pageblock.
Triggering the syzbot error requires that the end of pageblock is section
or zone aligned, and that the next section is unpopulated.

A more subtle consequence of the bug is that pageblocks were being
improperly used as migration targets which potentially hurts fragmentation
avoidance in the long-term one page at a time.

A debugging patch revealed that it's definitely possible to stray outside
of a pageblock which is not intended.  While syzbot cannot be used to
verify this patch, it was confirmed that the debugging warning no longer
triggers with this patch applied.  It has also been confirmed that the THP
allocation stress tests are not degraded by this patch.

Link: http://lkml.kernel.org/r/20190510182124.GI18914@techsingularity.net
Fixes: e332f741 ("mm, compaction: be selective about what pageblocks to clear skip hints")
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Reported-by: syzbot+d84c80f9fe26a0f7a734@syzkaller.appspotmail.com
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org> # v5.1+
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 0672d22a upstream.

Commit 6d4cd041 ("net: phy: at803x: disable delay only for RGMII mode")
exposed an issue on imx DTS files using AR8031/AR8035 PHYs.

The end result is that the boards can no longer obtain an IP address
via UDHCP, for example.

Quoting Andrew Lunn:

"The problem here is, all the DTs were broken since day 0. However,
because the PHY driver was also broken, nobody noticed and it
worked. Now that the PHY driver has been fixed, all the bugs in the
DTs now become an issue"

To fix this problem, the phy-mode property needs to be "rgmii-id",  which
has the following meaning as per
Documentation/devicetree/bindings/net/ethernet.txt:

"RGMII with internal RX and TX delays provided by the PHY, the MAC should
not add the RX or TX delays in this case)"

Tested on imx6-sabresd, imx6sx-sdb and imx7d-pico boards with
successfully restored networking.

Based on the initial submission from Steve Twiss for the
imx6qdl-sabresd.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Tested-by: Baruch Siach <baruch@tkos.co.il>
Tested-by: Soeren Moch <smoch@web.de>
Tested-by: Steve Twiss <stwiss.opensource@diasemi.com>
Tested-by: Adam Thomson <Adam.Thomson@diasemi.com>
Signed-off-by: Steve Twiss <stwiss.opensource@diasemi.com>
Tested-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Cc: "George G. Davis" <george_davis@mentor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 55be8658 upstream.

According to ipmi spec, block number is a number that is incremented,
starting with 0, for each new block of message data returned using the
middle transaction.

Here, the 'blocknum' is data[0] which always starts from zero(0) and
'ssif_info->multi_pos' starts from 1.
So, we need to add +1 to blocknum while comparing with multi_pos.

Fixes: 7d6380cd ("ipmi:ssif: Fix handling of multi-part return messages").
Reported-by: Kiran Kolukuluru <kirank@ami.com>
Signed-off-by: Kamlakant Patel <kamlakantp@marvell.com>
Message-Id: <1556106615-18722-1-git-send-email-kamlakantp@marvell.com>
[Also added a debug log if the block numbers don't match.]
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Cc: stable@vger.kernel.org # 4.4
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit d7323638 upstream.

This is required for SSIF to work.

There was no way to know if the interface being added was SI
or SSIF from the platform data, but that was required so the
i2c-addr is only added for SSIF interfaces.  So add a field
for that.

Also rework the logic a bit so that ipmi-type is not set
for SSIF interfaces, as it is not necessary for that.

Fixes: 3cd83bac ("ipmi: Consolidate the adding of platform devices")
Reported-by: Kamlakant Patel <kamlakantp@marvell.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Cc: stable@vger.kernel.org # 5.1
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 1bee2add upstream.

In journal_reclaim() ja->cur_idx of each cache will be update to
reclaim available journal buckets. Variable 'int n' is used to count how
many cache is successfully reclaimed, then n is set to c->journal.key
by SET_KEY_PTRS(). Later in journal_write_unlocked(), a for_each_cache()
loop will write the jset data onto each cache.

The problem is, if all jouranl buckets on each cache is full, the
following code in journal_reclaim(),

529 for_each_cache(ca, c, iter) {
530       struct journal_device *ja = &ca->journal;
531       unsigned int next = (ja->cur_idx + 1) % ca->sb.njournal_buckets;
532
533       /* No space available on this device */
534       if (next == ja->discard_idx)
535               continue;
536
537       ja->cur_idx = next;
538       k->ptr[n++] = MAKE_PTR(0,
539                         bucket_to_sector(c, ca->sb.d[ja->cur_idx]),
540                         ca->sb.nr_this_dev);
541 }
542
543 bkey_init(k);
544 SET_KEY_PTRS(k, n);

If there is no available bucket to reclaim, the if() condition at line
534 will always true, and n remains 0. Then at line 544, SET_KEY_PTRS()
will set KEY_PTRS field of c->journal.key to 0.

Setting KEY_PTRS field of c->journal.key to 0 is wrong. Because in
journal_write_unlocked() the journal data is written in following loop,

649	for (i = 0; i < KEY_PTRS(k); i++) {
650-671		submit journal data to cache device
672	}

If KEY_PTRS field is set to 0 in jouranl_reclaim(), the journal data
won't be written to cache device here. If system crahed or rebooted
before bkeys of the lost journal entries written into btree nodes, data
corruption will be reported during bcache reload after rebooting the
system.

Indeed there is only one cache in a cache set, there is no need to set
KEY_PTRS field in journal_reclaim() at all. But in order to keep the
for_each_cache() logic consistent for now, this patch fixes the above
problem by not setting 0 KEY_PTRS of journal key, if there is no bucket
available to reclaim.
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit a4b732a2 upstream.

There is a race between cache device register and cache set unregister.
For an already registered cache device, register_bcache will call
bch_is_open to iterate through all cachesets and check every cache
there. The race occurs if cache_set_free executes at the same time and
clears the caches right before ca is dereferenced in bch_is_open_cache.
To close the race, let's make sure the clean up work is protected by
the bch_register_lock as well.

This issue can be reproduced as follows,
while true; do echo /dev/XXX> /sys/fs/bcache/register ; done&
while true; do echo 1> /sys/block/XXX/bcache/set/unregister ; done &

and results in the following oops,

[  +0.000053] BUG: unable to handle kernel NULL pointer dereference at 0000000000000998
[  +0.000457] #PF error: [normal kernel read fault]
[  +0.000464] PGD 800000003ca9d067 P4D 800000003ca9d067 PUD 3ca9c067 PMD 0
[  +0.000388] Oops: 0000 [#1] SMP PTI
[  +0.000269] CPU: 1 PID: 3266 Comm: bash Not tainted 5.0.0+ #6
[  +0.000346] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.fc28 04/01/2014
[  +0.000472] RIP: 0010:register_bcache+0x1829/0x1990 [bcache]
[  +0.000344] Code: b0 48 83 e8 50 48 81 fa e0 e1 10 c0 0f 84 a9 00 00 00 48 89 c6 48 89 ca 0f b7 ba 54 04 00 00 4c 8b 82 60 0c 00 00 85 ff 74 2f <49> 3b a8 98 09 00 00 74 4e 44 8d 47 ff 31 ff 49 c1 e0 03 eb 0d
[  +0.000839] RSP: 0018:ffff92ee804cbd88 EFLAGS: 00010202
[  +0.000328] RAX: ffffffffc010e190 RBX: ffff918b5c6b5000 RCX: ffff918b7d8e0000
[  +0.000399] RDX: ffff918b7d8e0000 RSI: ffffffffc010e190 RDI: 0000000000000001
[  +0.000398] RBP: ffff918b7d318340 R08: 0000000000000000 R09: ffffffffb9bd2d7a
[  +0.000385] R10: ffff918b7eb253c0 R11: ffffb95980f51200 R12: ffffffffc010e1a0
[  +0.000411] R13: fffffffffffffff2 R14: 000000000000000b R15: ffff918b7e232620
[  +0.000384] FS:  00007f955bec2740(0000) GS:ffff918b7eb00000(0000) knlGS:0000000000000000
[  +0.000420] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  +0.000801] CR2: 0000000000000998 CR3: 000000003cad6000 CR4: 00000000001406e0
[  +0.000837] Call Trace:
[  +0.000682]  ? _cond_resched+0x10/0x20
[  +0.000691]  ? __kmalloc+0x131/0x1b0
[  +0.000710]  kernfs_fop_write+0xfa/0x170
[  +0.000733]  __vfs_write+0x2e/0x190
[  +0.000688]  ? inode_security+0x10/0x30
[  +0.000698]  ? selinux_file_permission+0xd2/0x120
[  +0.000752]  ? security_file_permission+0x2b/0x100
[  +0.000753]  vfs_write+0xa8/0x1a0
[  +0.000676]  ksys_write+0x4d/0xb0
[  +0.000699]  do_syscall_64+0x3a/0xf0
[  +0.000692]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 62d54f3a upstream.

Send operates on read only trees and expects them to never change while it
is using them. This is part of its initial design, and this expection is
due to two different reasons:

1) When it was introduced, no operations were allowed to modifiy read-only
   subvolumes/snapshots (including defrag for example).

2) It keeps send from having an impact on other filesystem operations.
   Namely send does not need to keep locks on the trees nor needs to hold on
   to transaction handles and delay transaction commits. This ends up being
   a consequence of the former reason.

However the deduplication feature was introduced later (on September 2013,
while send was introduced in July 2012) and it allowed for deduplication
with destination files that belong to read-only trees (subvolumes and
snapshots).

That means that having a send operation (either full or incremental) running
in parallel with a deduplication that has the destination inode in one of
the trees used by the send operation, can result in tree nodes and leaves
getting freed and reused while send is using them. This problem is similar
to the problem solved for the root nodes getting freed and reused when a
snapshot is made against one tree that is currenly being used by a send
operation, fixed in commits [1] and [2]. These commits explain in detail
how the problem happens and the explanation is valid for any node or leaf
that is not the root of a tree as well. This problem was also discussed
and explained recently in a thread [3].

The problem is very easy to reproduce when using send with large trees
(snapshots) and just a few concurrent deduplication operations that target
files in the trees used by send. A stress test case is being sent for
fstests that triggers the issue easily. The most common error to hit is
the send ioctl return -EIO with the following messages in dmesg/syslog:

 [1631617.204075] BTRFS error (device sdc): did not find backref in send_root. inode=63292, offset=0, disk_byte=5228134400 found extent=5228134400
 [1631633.251754] BTRFS error (device sdc): parent transid verify failed on 32243712 wanted 24 found 27

The first one is very easy to hit while the second one happens much less
frequently, except for very large trees (in that test case, snapshots
with 100000 files having large xattrs to get deep and wide trees).
Less frequently, at least one BUG_ON can be hit:

 [1631742.130080] ------------[ cut here ]------------
 [1631742.130625] kernel BUG at fs/btrfs/ctree.c:1806!
 [1631742.131188] invalid opcode: 0000 [#6] SMP DEBUG_PAGEALLOC PTI
 [1631742.131726] CPU: 1 PID: 13394 Comm: btrfs Tainted: G    B D W         5.0.0-rc8-btrfs-next-45 #1
 [1631742.132265] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
 [1631742.133399] RIP: 0010:read_node_slot+0x122/0x130 [btrfs]
 (...)
 [1631742.135061] RSP: 0018:ffffb530021ebaa0 EFLAGS: 00010246
 [1631742.135615] RAX: ffff93ac8912e000 RBX: 000000000000009d RCX: 0000000000000002
 [1631742.136173] RDX: 000000000000009d RSI: ffff93ac564b0d08 RDI: ffff93ad5b48c000
 [1631742.136759] RBP: ffffb530021ebb7d R08: 0000000000000001 R09: ffffb530021ebb7d
 [1631742.137324] R10: ffffb530021eba70 R11: 0000000000000000 R12: ffff93ac87d0a708
 [1631742.137900] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
 [1631742.138455] FS:  00007f4cdb1528c0(0000) GS:ffff93ad76a80000(0000) knlGS:0000000000000000
 [1631742.139010] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [1631742.139568] CR2: 00007f5acb3d0420 CR3: 000000012be3e006 CR4: 00000000003606e0
 [1631742.140131] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 [1631742.140719] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 [1631742.141272] Call Trace:
 [1631742.141826]  ? do_raw_spin_unlock+0x49/0xc0
 [1631742.142390]  tree_advance+0x173/0x1d0 [btrfs]
 [1631742.142948]  btrfs_compare_trees+0x268/0x690 [btrfs]
 [1631742.143533]  ? process_extent+0x1070/0x1070 [btrfs]
 [1631742.144088]  btrfs_ioctl_send+0x1037/0x1270 [btrfs]
 [1631742.144645]  _btrfs_ioctl_send+0x80/0x110 [btrfs]
 [1631742.145161]  ? trace_sched_stick_numa+0xe0/0xe0
 [1631742.145685]  btrfs_ioctl+0x13fe/0x3120 [btrfs]
 [1631742.146179]  ? account_entity_enqueue+0xd3/0x100
 [1631742.146662]  ? reweight_entity+0x154/0x1a0
 [1631742.147135]  ? update_curr+0x20/0x2a0
 [1631742.147593]  ? check_preempt_wakeup+0x103/0x250
 [1631742.148053]  ? do_vfs_ioctl+0xa2/0x6f0
 [1631742.148510]  ? btrfs_ioctl_get_supported_features+0x30/0x30 [btrfs]
 [1631742.148942]  do_vfs_ioctl+0xa2/0x6f0
 [1631742.149361]  ? __fget+0x113/0x200
 [1631742.149767]  ksys_ioctl+0x70/0x80
 [1631742.150159]  __x64_sys_ioctl+0x16/0x20
 [1631742.150543]  do_syscall_64+0x60/0x1b0
 [1631742.150931]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 [1631742.151326] RIP: 0033:0x7f4cd9f5add7
 (...)
 [1631742.152509] RSP: 002b:00007ffe91017708 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
 [1631742.152892] RAX: ffffffffffffffda RBX: 0000000000000105 RCX: 00007f4cd9f5add7
 [1631742.153268] RDX: 00007ffe91017790 RSI: 0000000040489426 RDI: 0000000000000007
 [1631742.153633] RBP: 0000000000000007 R08: 00007f4cd9e79700 R09: 00007f4cd9e79700
 [1631742.153999] R10: 00007f4cd9e799d0 R11: 0000000000000202 R12: 0000000000000003
 [1631742.154365] R13: 0000555dfae53020 R14: 0000000000000000 R15: 0000000000000001
 (...)
 [1631742.156696] ---[ end trace 5dac9f96dcc3fd6b ]---

That BUG_ON happens because while send is using a node, that node is COWed
by a concurrent deduplication, gets freed and gets reused as a leaf (because
a transaction commit happened in between), so when it attempts to read a
slot from the extent buffer, at ctree.c:read_node_slot(), the extent buffer
contents were wiped out and it now matches a leaf (which can even belong to
some other tree now), hitting the BUG_ON(level == 0).

Fix this concurrency issue by not allowing send and deduplication to run
in parallel if both operate on the same readonly trees, returning EAGAIN
to user space and logging an exlicit warning in dmesg/syslog.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=be6821f82c3cc36e026f5afd10249988852b35ea
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6f2f0b394b54e2b159ef969a0b5274e9bbf82ff2
[3] https://lore.kernel.org/linux-btrfs/CAL3q7H7iqSEEyFaEtpRZw3cp613y+4k2Q8b4W7mweR3tZA05bQ@mail.gmail.com/

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit bfc61c36 upstream.

When finding out which inodes have references on a particular extent, done
by backref.c:iterate_extent_inodes(), from the BTRFS_IOC_LOGICAL_INO (both
v1 and v2) ioctl and from scrub we use the transaction join API to grab a
reference on the currently running transaction, since in order to give
accurate results we need to inspect the delayed references of the currently
running transaction.

However, if there is currently no running transaction, the join operation
will create a new transaction. This is inefficient as the transaction will
eventually be committed, doing unnecessary IO and introducing a potential
point of failure that will lead to a transaction abort due to -ENOSPC, as
recently reported [1].

That's because the join, creates the transaction but does not reserve any
space, so when attempting to update the root item of the root passed to
btrfs_join_transaction(), during the transaction commit, we can end up
failling with -ENOSPC. Users of a join operation are supposed to actually
do some filesystem changes and reserve space by some means, which is not
the case of iterate_extent_inodes(), it is a read-only operation for all
contextes from which it is called.

The reported [1] -ENOSPC failure stack trace is the following:

 heisenberg kernel: ------------[ cut here ]------------
 heisenberg kernel: BTRFS: Transaction aborted (error -28)
 heisenberg kernel: WARNING: CPU: 0 PID: 7137 at fs/btrfs/root-tree.c:136 btrfs_update_root+0x22b/0x320 [btrfs]
(...)
 heisenberg kernel: CPU: 0 PID: 7137 Comm: btrfs-transacti Not tainted 4.19.0-4-amd64 #1 Debian 4.19.28-2
 heisenberg kernel: Hardware name: FUJITSU LIFEBOOK U757/FJNB2A5, BIOS Version 1.21 03/19/2018
 heisenberg kernel: RIP: 0010:btrfs_update_root+0x22b/0x320 [btrfs]
(...)
 heisenberg kernel: RSP: 0018:ffffb5448828bd40 EFLAGS: 00010286
 heisenberg kernel: RAX: 0000000000000000 RBX: ffff8ed56bccef50 RCX: 0000000000000006
 heisenberg kernel: RDX: 0000000000000007 RSI: 0000000000000092 RDI: ffff8ed6bda166a0
 heisenberg kernel: RBP: 00000000ffffffe4 R08: 00000000000003df R09: 0000000000000007
 heisenberg kernel: R10: 0000000000000000 R11: 0000000000000001 R12: ffff8ed63396a078
 heisenberg kernel: R13: ffff8ed092d7c800 R14: ffff8ed64f5db028 R15: ffff8ed6bd03d068
 heisenberg kernel: FS:  0000000000000000(0000) GS:ffff8ed6bda00000(0000) knlGS:0000000000000000
 heisenberg kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 heisenberg kernel: CR2: 00007f46f75f8000 CR3: 0000000310a0a002 CR4: 00000000003606f0
 heisenberg kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 heisenberg kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 heisenberg kernel: Call Trace:
 heisenberg kernel:  commit_fs_roots+0x166/0x1d0 [btrfs]
 heisenberg kernel:  ? _cond_resched+0x15/0x30
 heisenberg kernel:  ? btrfs_run_delayed_refs+0xac/0x180 [btrfs]
 heisenberg kernel:  btrfs_commit_transaction+0x2bd/0x870 [btrfs]
 heisenberg kernel:  ? start_transaction+0x9d/0x3f0 [btrfs]
 heisenberg kernel:  transaction_kthread+0x147/0x180 [btrfs]
 heisenberg kernel:  ? btrfs_cleanup_transaction+0x530/0x530 [btrfs]
 heisenberg kernel:  kthread+0x112/0x130
 heisenberg kernel:  ? kthread_bind+0x30/0x30
 heisenberg kernel:  ret_from_fork+0x35/0x40
 heisenberg kernel: ---[ end trace 05de912e30e012d9 ]---

So fix that by using the attach API, which does not create a transaction
when there is currently no running transaction.

[1] https://lore.kernel.org/linux-btrfs/b2a668d7124f1d3e410367f587926f622b3f03a4.camel@scientia.net/Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 03628cdb upstream.

During fiemap, for regular extents (non inline) we need to check if they
are shared and if they are, set the shared bit. Checking if an extent is
shared requires checking the delayed references of the currently running
transaction, since some reference might have not yet hit the extent tree
and be only in the in-memory delayed references.

However we were using a transaction join for this, which creates a new
transaction when there is no transaction currently running. That means
that two more potential failures can happen: creating the transaction and
committing it. Further, if no write activity is currently happening in the
system, and fiemap calls keep being done, we end up creating and
committing transactions that do nothing.

In some extreme cases this can result in the commit of the transaction
created by fiemap to fail with ENOSPC when updating the root item of a
subvolume tree because a join does not reserve any space, leading to a
trace like the following:

 heisenberg kernel: ------------[ cut here ]------------
 heisenberg kernel: BTRFS: Transaction aborted (error -28)
 heisenberg kernel: WARNING: CPU: 0 PID: 7137 at fs/btrfs/root-tree.c:136 btrfs_update_root+0x22b/0x320 [btrfs]
(...)
 heisenberg kernel: CPU: 0 PID: 7137 Comm: btrfs-transacti Not tainted 4.19.0-4-amd64 #1 Debian 4.19.28-2
 heisenberg kernel: Hardware name: FUJITSU LIFEBOOK U757/FJNB2A5, BIOS Version 1.21 03/19/2018
 heisenberg kernel: RIP: 0010:btrfs_update_root+0x22b/0x320 [btrfs]
(...)
 heisenberg kernel: RSP: 0018:ffffb5448828bd40 EFLAGS: 00010286
 heisenberg kernel: RAX: 0000000000000000 RBX: ffff8ed56bccef50 RCX: 0000000000000006
 heisenberg kernel: RDX: 0000000000000007 RSI: 0000000000000092 RDI: ffff8ed6bda166a0
 heisenberg kernel: RBP: 00000000ffffffe4 R08: 00000000000003df R09: 0000000000000007
 heisenberg kernel: R10: 0000000000000000 R11: 0000000000000001 R12: ffff8ed63396a078
 heisenberg kernel: R13: ffff8ed092d7c800 R14: ffff8ed64f5db028 R15: ffff8ed6bd03d068
 heisenberg kernel: FS:  0000000000000000(0000) GS:ffff8ed6bda00000(0000) knlGS:0000000000000000
 heisenberg kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 heisenberg kernel: CR2: 00007f46f75f8000 CR3: 0000000310a0a002 CR4: 00000000003606f0
 heisenberg kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 heisenberg kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 heisenberg kernel: Call Trace:
 heisenberg kernel:  commit_fs_roots+0x166/0x1d0 [btrfs]
 heisenberg kernel:  ? _cond_resched+0x15/0x30
 heisenberg kernel:  ? btrfs_run_delayed_refs+0xac/0x180 [btrfs]
 heisenberg kernel:  btrfs_commit_transaction+0x2bd/0x870 [btrfs]
 heisenberg kernel:  ? start_transaction+0x9d/0x3f0 [btrfs]
 heisenberg kernel:  transaction_kthread+0x147/0x180 [btrfs]
 heisenberg kernel:  ? btrfs_cleanup_transaction+0x530/0x530 [btrfs]
 heisenberg kernel:  kthread+0x112/0x130
 heisenberg kernel:  ? kthread_bind+0x30/0x30
 heisenberg kernel:  ret_from_fork+0x35/0x40
 heisenberg kernel: ---[ end trace 05de912e30e012d9 ]---

Since fiemap (and btrfs_check_shared()) is a read-only operation, do not do
a transaction join to avoid the overhead of creating a new transaction (if
there is currently no running transaction) and introducing a potential
point of failure when the new transaction gets committed, instead use a
transaction attach to grab a handle for the currently running transaction
if any.
Reported-by: Christoph Anton Mitterer <calestyo@scientia.net>
Link: https://lore.kernel.org/linux-btrfs/b2a668d7124f1d3e410367f587926f622b3f03a4.camel@scientia.net/
Fixes: afce772e ("btrfs: fix check_shared for fiemap ioctl")
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 9f89d5de upstream.

When we set a subvolume to read-only mode we do not flush dellaloc for any
of its inodes (except if the filesystem is mounted with -o flushoncommit),
since it does not affect correctness for any subsequent operations - except
for a future send operation. The send operation will not be able to see the
delalloc data since the respective file extent items, inode item updates,
backreferences, etc, have not hit yet the subvolume and extent trees.

Effectively this means data loss, since the send stream will not contain
any data from existing delalloc. Another problem from this is that if the
writeback starts and finishes while the send operation is in progress, we
have the subvolume tree being being modified concurrently which can result
in send failing unexpectedly with EIO or hitting runtime errors, assertion
failures or hitting BUG_ONs, etc.

Simple reproducer:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ btrfs subvolume create /mnt/sv
  $ xfs_io -f -c "pwrite -S 0xea 0 108K" /mnt/sv/foo

  $ btrfs property set /mnt/sv ro true
  $ btrfs send -f /tmp/send.stream /mnt/sv

  $ od -t x1 -A d /mnt/sv/foo
  0000000 ea ea ea ea ea ea ea ea ea ea ea ea ea ea ea ea
  *
  0110592

  $ umount /mnt
  $ mkfs.btrfs -f /dev/sdc
  $ mount /dev/sdc /mnt

  $ btrfs receive -f /tmp/send.stream /mnt
  $ echo $?
  0
  $ od -t x1 -A d /mnt/sv/foo
  0000000
  # ---> empty file

Since this a problem that affects send only, fix it in send by flushing
dellaloc for all the roots used by the send operation before send starts
to process the commit roots.

This is a problem that affects send since it was introduced (commit
31db9f7c ("Btrfs: introduce BTRFS_IOC_SEND for btrfs send/receive"))
but backporting it to older kernels has some dependencies:

- For kernels between 3.19 and 4.20, it depends on commit 3cd24c69
  ("btrfs: use tagged writepage to mitigate livelock of snapshot") because
  the function btrfs_start_delalloc_snapshot() does not exist before that
  commit. So one has to either pick that commit or replace the calls to
  btrfs_start_delalloc_snapshot() in this patch with calls to
  btrfs_start_delalloc_inodes().

- For kernels older than 3.19 it also requires commit e5fa8f86
  ("Btrfs: ensure send always works on roots without orphans") because
  it depends on the function ensure_commit_roots_uptodate() which that
  commits introduced.

- No dependencies for 5.0+ kernels.

A test case for fstests follows soon.

CC: stable@vger.kernel.org # 3.19+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit c2d1b3aa upstream.

Up until now trimming the freespace was done irrespective of what the
arguments of the FITRIM ioctl were. For example fstrim's -o/-l arguments
will be entirely ignored. Fix it by correctly handling those paramter.
This requires breaking if the found freespace extent is after the end of
the passed range as well as completing trim after trimming
fstrim_range::len bytes.

Fixes: 499f377f ("btrfs: iterate over unused chunk space in FITRIM")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 537f38f0 upstream.

If a an eb fails to be read for whatever reason - it's corrupted on disk
and parent transid/key validations fail or IO for eb pages fail then
this buffer must be removed from the buffer cache. Currently the code
calls free_extent_buffer if an error occurs. Unfortunately this doesn't
achieve the desired behavior since btrfs_find_create_tree_block returns
with eb->refs == 2.

On the other hand free_extent_buffer will only decrement the refs once
leaving it added to the buffer cache radix tree.  This enables later
code to look up the buffer from the cache and utilize it potentially
leading to a crash.

The correct way to free the buffer is call free_extent_buffer_stale.
This function will correctly call atomic_dec explicitly for the buffer
and subsequently call release_extent_buffer which will decrement the
final reference thus correctly remove the invalid buffer from buffer
cache. This change affects only newly allocated buffers since they have
eb->refs == 2.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=202755Reported-by: Jungyeon <jungyeon@gatech.edu>
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>