linux-toradex.git/fs/btrfs, branch v4.9.35

crypto: Work around deallocated stack frame reference gcc bug on sparc.

2017-06-24T05:11:17+00:00

commit d41519a69b35b10af7fda867fb9100df24fdf403 upstream.

On sparc, if we have an alloca() like situation, as is the case with
SHASH_DESC_ON_STACK(), we can end up referencing deallocated stack
memory.  The result can be that the value is clobbered if a trap
or interrupt arrives at just the right instruction.

It only occurs if the function ends returning a value from that
alloca() area and that value can be placed into the return value
register using a single instruction.

For example, in lib/libcrc32c.c:crc32c() we end up with a return
sequence like:

        return  %i7+8
         lduw   [%o5+16], %o0   ! MEM[(u32 *)__shash_desc.1_10 + 16B],

%o5 holds the base of the on-stack area allocated for the shash
descriptor.  But the return released the stack frame and the
register window.

So if an intererupt arrives between 'return' and 'lduw', then
the value read at %o5+16 can be corrupted.

Add a data compiler barrier to work around this problem.  This is
exactly what the gcc fix will end up doing as well, and it absolutely
should not change the code generated for other cpus (unless gcc
on them has the same bug :-)

With crucial insight from Eric Sandeen.

Reported-by: Anatoly Pugachev 
Signed-off-by: David S. Miller 
Signed-off-by: Herbert Xu 
Signed-off-by: Greg Kroah-Hartman

btrfs: fix memory leak in update_space_info failure path

2017-06-14T13:06:02+00:00

commit 896533a7da929136d0432713f02a3edffece2826 upstream.

If we fail to add the space_info kobject, we'll leak the memory
for the percpu counter.

Fixes: 6ab0a2029c (btrfs: publish allocation data in sysfs)
Signed-off-by: Jeff Mahoney 
Reviewed-by: Liu Bo 
Signed-off-by: David Sterba 
Signed-off-by: Greg Kroah-Hartman

btrfs: use correct types for page indices in btrfs_page_exists_in_range

2017-06-14T13:06:02+00:00

commit cc2b702c52094b637a351d7491ac5200331d0445 upstream.

Variables start_idx and end_idx are supposed to hold a page index
derived from the file offsets. The int type is not the right one though,
offsets larger than 1 << 44 will get silently trimmed off the high bits.
(1 << 44 is 16TiB)

What can go wrong, if start is below the boundary and end gets trimmed:
- if there's a page after start, we'll find it (radix_tree_gang_lookup_slot)
- the final check "if (page->index <= end_idx)" will unexpectedly fail

The function will return false, ie. "there's no page in the range",
although there is at least one.

btrfs_page_exists_in_range is used to prevent races in:

* in hole punching, where we make sure there are not pages in the
  truncated range, otherwise we'll wait for them to finish and redo
  truncation, but we're going to replace the pages with holes anyway so
  the only problem is the intermediate state

* lock_extent_direct: we want to make sure there are no pages before we
  lock and start DIO, to prevent stale data reads

For practical occurence of the bug, there are several constaints.  The
file must be quite large, the affected range must cross the 16TiB
boundary and the internal state of the file pages and pending operations
must match.  Also, we must not have started any ordered data in the
range, otherwise we don't even reach the buggy function check.

DIO locking tries hard in several places to avoid deadlocks with
buffered IO and avoids waiting for ranges. The worst consequence seems
to be stale data read.

CC: Liu Bo 
Fixes: fc4adbff823f7 ("btrfs: Drop EXTENT_UPTODATE check in hole punching and direct locking")
Reviewed-by: Liu Bo 
Signed-off-by: David Sterba 
Signed-off-by: Greg Kroah-Hartman

fs: add i_blocksize()

2017-06-14T13:06:00+00:00

commit 93407472a21b82f39c955ea7787e5bc7da100642 upstream.

Replace all 1 << inode->i_blkbits and (1 << inode->i_blkbits) in fs
branch.

This patch also fixes multiple checkpatch warnings: WARNING: Prefer
'unsigned int' to bare use of 'unsigned'

Thanks to Andrew Morton for suggesting more appropriate function instead
of macro.

[geliangtang@gmail.com: truncate: use i_blocksize()]
  Link: http://lkml.kernel.org/r/9c8b2cd83c8f5653805d43debde9fa8817e02fc4.1484895804.git.geliangtang@gmail.com
Link: http://lkml.kernel.org/r/1481319905-10126-1-git-send-email-fabf@skynet.be
Signed-off-by: Fabian Frederick 
Signed-off-by: Geliang Tang 
Cc: Alexander Viro 
Cc: Ross Zwisler 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

btrfs: fix btrfs_compat_ioctl failures on non-compat ioctls

2017-02-14T23:25:40+00:00

commit 2a362249187a8d0f6d942d6e1d763d150a296f47 upstream.

Commit 4c63c2454ef incorrectly assumed that returning -ENOIOCTLCMD would
cause the native ioctl to be called.  The ->compat_ioctl callback is
expected to handle all ioctls, not just compat variants.  As a result,
when using 32-bit userspace on 64-bit kernels, everything except those
three ioctls would return -ENOTTY.

Fixes: 4c63c2454ef ("btrfs: bugfix: handle FS_IOC32_{GETFLAGS,SETFLAGS,GETVERSION} in btrfs_ioctl")
Signed-off-by: Jeff Mahoney 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba 
Signed-off-by: Greg Kroah-Hartman

Btrfs: remove ->{get, set}_acl() from btrfs_dir_ro_inode_operations

2017-02-01T07:33:06+00:00

commit 57b59ed2e5b91e958843609c7884794e29e6c4cb upstream.

Subvolume directory inodes can't have ACLs.

Signed-off-by: Omar Sandoval 
Reviewed-by: David Sterba 
Signed-off-by: Chris Mason 
Signed-off-by: Greg Kroah-Hartman

Btrfs: disable xattr operations on subvolume directories

2017-02-01T07:33:06+00:00

commit 1fdf41941b8010691679638f8d0c8d08cfee7726 upstream.

When you snapshot a subvolume containing a subvolume, you get a
placeholder directory where the subvolume would be. These directory
inodes have ->i_ops set to btrfs_dir_ro_inode_operations. Previously,
these i_ops didn't include the xattr operation callbacks. The conversion
to xattr_handlers missed this case, leading to bogus attempts to set
xattrs on these inodes. This manifested itself as failures when running
delayed inodes.

To fix this, clear IOP_XATTR in ->i_opflags on these inodes.

Fixes: 6c6ef9f26e59 ("xattr: Stop calling {get,set,remove}xattr inode operations")
Cc: Andreas Gruenbacher 
Reported-by: Chris Murphy 
Tested-by: Chris Murphy 
Signed-off-by: Omar Sandoval 
Reviewed-by: David Sterba 
Signed-off-by: Chris Mason 
Signed-off-by: Greg Kroah-Hartman

Btrfs: remove old tree_root case in btrfs_read_locked_inode()

2017-02-01T07:33:06+00:00

commit 67ade058ef2c65a3e56878af9c293ec76722a2e5 upstream.

As Jeff explained in c2951f32d36c ("btrfs: remove old tree_root dirent
processing in btrfs_real_readdir()"), supporting this old format is no
longer necessary since the Btrfs magic number has been updated since we
changed to the current format. There are other places where we still
handle this old format, but since this is part of a fix that is going to
stable, I'm only removing this one for now.

Signed-off-by: Omar Sandoval 
Reviewed-by: David Sterba 
Signed-off-by: Chris Mason 
Signed-off-by: Greg Kroah-Hartman

btrfs: fix error handling when run_delayed_extent_op fails

2017-01-19T19:18:05+00:00

commit aa7c8da35d1905d80e840d075f07d26ec90144b5 upstream.

In __btrfs_run_delayed_refs, the error path when run_delayed_extent_op
fails sets locked_ref->processing = 0 but doesn't re-increment
delayed_refs->num_heads_ready.  As a result, we end up triggering
the WARN_ON in btrfs_select_ref_head.

Fixes: d7df2c796d7 (Btrfs: attach delayed ref updates to delayed ref heads)
Reported-by: Jon Nelson 
Signed-off-by: Jeff Mahoney 
Reviewed-by: Liu Bo 
Signed-off-by: David Sterba 
Signed-off-by: Greg Kroah-Hartman

btrfs: fix locking when we put back a delayed ref that's too new

2017-01-19T19:18:05+00:00

commit d0280996437081dd12ed1e982ac8aeaa62835ec4 upstream.

In __btrfs_run_delayed_refs, when we put back a delayed ref that's too
new, we have already dropped the lock on locked_ref when we set
->processing = 0.

This patch keeps the lock to cover that assignment.

Fixes: d7df2c796d7 (Btrfs: attach delayed ref updates to delayed ref heads)
Signed-off-by: Jeff Mahoney 
Reviewed-by: Liu Bo 
Signed-off-by: David Sterba 
Signed-off-by: Greg Kroah-Hartman