Pull vfs fixes from Al Viro:
"Fix several places that screw up cleanups after failures halfway
through opening a file (one open-coding filp_clone_open() and getting
it wrong, two misusing alloc_file()). That part is -stable fodder from
the 'work.open' branch.
And Christoph's regression fix for uapi breakage in aio series;
include/uapi/linux/aio_abi.h shouldn't be pulling in the kernel
definition of sigset_t, the reason for doing so in the first place had
been bogus - there's no need to expose struct __aio_sigset in
aio_abi.h at all"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
aio: don't expose __aio_sigset in uapi
ocxlflash_getfile(): fix double-iput() on alloc_file() failures
cxl_getfile(): fix double-iput() on alloc_file() failures
drm_mode_create_lease_ioctl(): fix open-coded filp_clone_open()
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Merge tag 'for-4.18-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fix from David Sterba:
"A fix of a corruption regarding fsync and clone, under some very
specific conditions explained in the patch.
The fix is marked for stable 3.16+ so I'd like to get it merged now
given the impact"
* tag 'for-4.18-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix file data corruption after cloning a range and fsync
Like vm_area_dup(), it initializes the anon_vma_chain head, and the
basic mm pointer.
The rest of the fields end up being different for different users,
although the plan is to also initialize the 'vm_ops' field to a dummy
entry.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The vm_area_struct is one of the most fundamental memory management
objects, but the management of it is entirely open-coded evertwhere,
ranging from allocation and freeing (using kmem_cache_[z]alloc and
kmem_cache_free) to initializing all the fields.
We want to unify this in order to end up having some unified
initialization of the vmas, and the first step to this is to at least
have basic allocation functions.
Right now those functions are literally just wrappers around the
kmem_cache_*() calls. This is a purely mechanical conversion:
# new vma:
kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL) -> vm_area_alloc()
# copy old vma
kmem_cache_alloc(vm_area_cachep, GFP_KERNEL) -> vm_area_dup(old)
# free vma
kmem_cache_free(vm_area_cachep, vma) -> vm_area_free(vma)
to the point where the old vma passed in to the vm_area_dup() function
isn't even used yet (because I've left all the old manual initialization
alone).
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In parse_options(), if match_strdup() failed, parse_options() leaves
opts->iocharset in unexpected state (i.e. still pointing the freed
string). And this can be the cause of double free.
To fix, this initialize opts->iocharset always when freeing.
Link: http://lkml.kernel.org/r/8736wp9dzc.fsf@mail.parknet.co.jp
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Reported-by: syzbot+90b8e10515ae88228a92@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When we clone a range into a file we can end up dropping existing
extent maps (or trimming them) and replacing them with new ones if the
range to be cloned overlaps with a range in the destination inode.
When that happens we add the new extent maps to the list of modified
extents in the inode's extent map tree, so that a "fast" fsync (the flag
BTRFS_INODE_NEEDS_FULL_SYNC not set in the inode) will see the extent maps
and log corresponding extent items. However, at the end of range cloning
operation we do truncate all the pages in the affected range (in order to
ensure future reads will not get stale data). Sometimes this truncation
will release the corresponding extent maps besides the pages from the page
cache. If this happens, then a "fast" fsync operation will miss logging
some extent items, because it relies exclusively on the extent maps being
present in the inode's extent tree, leading to data loss/corruption if
the fsync ends up using the same transaction used by the clone operation
(that transaction was not committed in the meanwhile). An extent map is
released through the callback btrfs_invalidatepage(), which gets called by
truncate_inode_pages_range(), and it calls __btrfs_releasepage(). The
later ends up calling try_release_extent_mapping() which will release the
extent map if some conditions are met, like the file size being greater
than 16Mb, gfp flags allow blocking and the range not being locked (which
is the case during the clone operation) nor being the extent map flagged
as pinned (also the case for cloning).
The following example, turned into a test for fstests, reproduces the
issue:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ xfs_io -f -c "pwrite -S 0x18 9000K 6908K" /mnt/foo
$ xfs_io -f -c "pwrite -S 0x20 2572K 156K" /mnt/bar
$ xfs_io -c "fsync" /mnt/bar
# reflink destination offset corresponds to the size of file bar,
# 2728Kb minus 4Kb.
$ xfs_io -c ""reflink ${SCRATCH_MNT}/foo 0 2724K 15908K" /mnt/bar
$ xfs_io -c "fsync" /mnt/bar
$ md5sum /mnt/bar
95a95813a8c2abc9aa75a6c2914a077e /mnt/bar
<power fail>
$ mount /dev/sdb /mnt
$ md5sum /mnt/bar
207fd8d0b161be8a84b945f0df8d5f8d /mnt/bar
# digest should be 95a95813a8c2abc9aa75a6c2914a077e like before the
# power failure
In the above example, the destination offset of the clone operation
corresponds to the size of the "bar" file minus 4Kb. So during the clone
operation, the extent map covering the range from 2572Kb to 2728Kb gets
trimmed so that it ends at offset 2724Kb, and a new extent map covering
the range from 2724Kb to 11724Kb is created. So at the end of the clone
operation when we ask to truncate the pages in the range from 2724Kb to
2724Kb + 15908Kb, the page invalidation callback ends up removing the new
extent map (through try_release_extent_mapping()) when the page at offset
2724Kb is passed to that callback.
Fix this by setting the bit BTRFS_INODE_NEEDS_FULL_SYNC whenever an extent
map is removed at try_release_extent_mapping(), forcing the next fsync to
search for modified extents in the fs/subvolume tree instead of relying on
the presence of extent maps in memory. This way we can continue doing a
"fast" fsync if the destination range of a clone operation does not
overlap with an existing range or if any of the criteria necessary to
remove an extent map at try_release_extent_mapping() is not met (file
size not bigger then 16Mb or gfp flags do not allow blocking).
CC: stable@vger.kernel.org # 3.16+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
glibc uses a different defintion of sigset_t than the kernel does,
and the current version would pull in both. To fix this just do not
expose the type at all - this somewhat mirrors pselect() where we
do not even have a type for the magic sigmask argument, but just
use pointer arithmetics.
Fixes: 7a074e96 ("aio: implement io_pgetevents")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Adrian Reber <adrian@lisas.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In commit ac0b4145d6 ("btrfs: scrub: Don't use inode pages for device
replace") we removed the branch of copy_nocow_pages() to avoid
corruption for compressed nodatasum extents.
However above commit only solves the problem in scrub_extent(), if
during scrub_pages() we failed to read some pages,
sctx->no_io_error_seen will be non-zero and we go to fixup function
scrub_handle_errored_block().
In scrub_handle_errored_block(), for sctx without csum (no matter if
we're doing replace or scrub) we go to scrub_fixup_nodatasum() routine,
which does the similar thing with copy_nocow_pages(), but does it
without the extra check in copy_nocow_pages() routine.
So for test cases like btrfs/100, where we emulate read errors during
replace/scrub, we could corrupt compressed extent data again.
This patch will fix it just by avoiding any "optimization" for
nodatasum, just falls back to the normal fixup routine by try read from
any good copy.
This also solves WARN_ON() or dead lock caused by lame backref iteration
in scrub_fixup_nodatasum() routine.
The deadlock or WARN_ON() won't be triggered before commit ac0b4145d6
("btrfs: scrub: Don't use inode pages for device replace") since
copy_nocow_pages() have better locking and extra check for data extent,
and it's already doing the fixup work by try to read data from any good
copy, so it won't go scrub_fixup_nodatasum() anyway.
This patch disables the faulty code and will be removed completely in a
followup patch.
Fixes: ac0b4145d6 ("btrfs: scrub: Don't use inode pages for device replace")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
ReiserFS prepares log messages into a 1024-byte buffer with no bounds
checks. Long messages, such as the "unknown mount option" warning when
userspace passes a crafted mount options string, overflow this buffer.
This causes KASAN to report a global-out-of-bounds write.
Fix it by truncating messages to the buffer size.
Link: http://lkml.kernel.org/r/20180707203621.30922-1-ebiggers3@gmail.com
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot+b890b3335a4d8c608963@syzkaller.appspotmail.com
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The current code does not make sure to page align bss before calling
vm_brk(), and this can lead to a VM_BUG_ON() in __mm_populate() due to
the requested lenght not being correctly aligned.
Let us make sure to align it properly.
Kees: only applicable to CONFIG_USELIB kernels: 32-bit and configured
for libc5.
Link: http://lkml.kernel.org/r/20180705145539.9627-1-osalvador@techadventures.net
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Reported-by: syzbot+5dcb560fe12aa5091c06@syzkaller.appspotmail.com
Tested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The autofs subsystem does not check that the "path" parameter is present
for all cases where it is required when it is passed in via the "param"
struct.
In particular it isn't checked for the AUTOFS_DEV_IOCTL_OPENMOUNT_CMD
ioctl command.
To solve it, modify validate_dev_ioctl(function to check that a path has
been provided for ioctl commands that require it.
Link: http://lkml.kernel.org/r/153060031527.26631.18306637892746301555.stgit@pluto.themaw.net
Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com>
Signed-off-by: Ian Kent <raven@themaw.net>
Reported-by: syzbot+60c837b428dc84e83a93@syzkaller.appspotmail.com
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Thomas reports:
"While looking around in /proc on my v4.14.52 system I noticed that all
processes got a lot of "Locked" memory in /proc/*/smaps. A lot more
memory than a regular user can usually lock with mlock().
Commit 493b0e9d94 (in v4.14-rc1) seems to have changed the behavior
of "Locked".
Before that commit the code was like this. Notice the VM_LOCKED check.
(vma->vm_flags & VM_LOCKED) ?
(unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
After that commit Locked is now the same as Pss:
(unsigned long)(mss->pss >> (10 + PSS_SHIFT)));
This looks like a mistake."
Indeed, the commit has added mss->pss_locked with the correct value that
depends on VM_LOCKED, but forgot to actually use it. Fix it.
Link: http://lkml.kernel.org/r/ebf6c7fb-fec3-6a26-544f-710ed193c154@suse.cz
Fixes: 493b0e9d94 ("mm: add /proc/pid/smaps_rollup")
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Thomas Lindroth <thomas.lindroth@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Daniel Colascione <dancol@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
btrfs_cmp_data_free() puts cmp's src_pages and dst_pages, but leaves
their page address intact. Now, if you hit "goto again" in
btrfs_extent_same_range() and hit some error in
btrfs_cmp_data_prepare(), you'll try to unlock/put already put pages.
This is simple fix to reset the address to avoid use-after-free.
Fixes: 67b07bd4be ("Btrfs: reuse cmp workspace in EXTENT_SAME ioctl")
Signed-off-by: Naohiro Aota <naota@elisp.net>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit 542c5908ab ("btrfs: replace uuid_mutex by
device_list_mutex in btrfs_open_devices") switched to device_list_mutex
as we need that for the device list traversal, but we also need
uuid_mutex to protect access to fs_devices::opened to be consistent with
other users of that.
Fixes: 542c5908ab ("btrfs: replace uuid_mutex by device_list_mutex in btrfs_open_devices")
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Failure of ->open() should *not* be followed by fput(). Fixed by
using filp_clone_open(), which gets the cleanups right.
Cc: stable@vger.kernel.org
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
maliciously crafted file system image can result in a kernel OOPS or
hang. At least one fix addresses an inline data bug could be
triggered by userspace without the need of a crafted file system
(although it does require that the inline data feature be enabled).
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 bugfixes from Ted Ts'o:
"Bug fixes for ext4; most of which relate to vulnerabilities where a
maliciously crafted file system image can result in a kernel OOPS or
hang.
At least one fix addresses an inline data bug could be triggered by
userspace without the need of a crafted file system (although it does
require that the inline data feature be enabled)"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: check superblock mapped prior to committing
ext4: add more mount time checks of the superblock
ext4: add more inode number paranoia checks
ext4: avoid running out of journal credits when appending to an inline file
jbd2: don't mark block as modified if the handle is out of credits
ext4: never move the system.data xattr out of the inode body
ext4: clear i_data in ext4_inode_info when removing inline data
ext4: include the illegal physical block in the bad map ext4_error msg
ext4: verify the depth of extent tree in ext4_find_extent()
ext4: only look at the bg_flags field if it is valid
ext4: make sure bitmaps and the inode table don't overlap with bg descriptors
ext4: always check block group bounds in ext4_init_block_bitmap()
ext4: always verify the magic number in xattr blocks
ext4: add corruption check in ext4_xattr_set_entry()
ext4: add warn_on_error mount option
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Merge tag '4.18-rc3-smb3fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Five smb3/cifs fixes for stable (including for some leaks and memory
overwrites) and also a few fixes for recent regressions in packet
signing.
Additional testing at the recent SMB3 test event, and some good work
by Paulo and others spotted the issues fixed here. In addition to my
xfstest runs on these, Aurelien and Stefano did additional test runs
to verify this set"
* tag '4.18-rc3-smb3fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: Fix stack out-of-bounds in smb{2,3}_create_lease_buf()
cifs: Fix infinite loop when using hard mount option
cifs: Fix slab-out-of-bounds in send_set_info() on SMB2 ACE setting
cifs: Fix memory leak in smb2_set_ea()
cifs: fix SMB1 breakage
cifs: Fix validation of signed data in smb2
cifs: Fix validation of signed data in smb3+
cifs: Fix use after free of a mid_q_entry
sgid directories have special semantics, making newly created files in
the directory belong to the group of the directory, and newly created
subdirectories will also become sgid. This is historically used for
group-shared directories.
But group directories writable by non-group members should not imply
that such non-group members can magically join the group, so make sure
to clear the sgid bit on non-directories for non-members (but remember
that sgid without group execute means "mandatory locking", just to
confuse things even more).
Reported-by: Jann Horn <jannh@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For every request we send, whether it is SMB1 or SMB2+, we attempt to
reconnect tcon (cifs_reconnect_tcon or smb2_reconnect) before carrying
out the request.
So, while server->tcpStatus != CifsNeedReconnect, we wait for the
reconnection to succeed on wait_event_interruptible_timeout(). If it
returns, that means that either the condition was evaluated to true, or
timeout elapsed, or it was interrupted by a signal.
Since we're not handling the case where the process woke up due to a
received signal (-ERESTARTSYS), the next call to
wait_event_interruptible_timeout() will _always_ fail and we end up
looping forever inside either cifs_reconnect_tcon() or smb2_reconnect().
Here's an example of how to trigger that:
$ mount.cifs //foo/share /mnt/test -o
username=foo,password=foo,vers=1.0,hard
(break connection to server before executing bellow cmd)
$ stat -f /mnt/test & sleep 140
[1] 2511
$ ps -aux -q 2511
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 2511 0.0 0.0 12892 1008 pts/0 S 12:24 0:00 stat -f
/mnt/test
$ kill -9 2511
(wait for a while; process is stuck in the kernel)
$ ps -aux -q 2511
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 2511 83.2 0.0 12892 1008 pts/0 R 12:24 30:01 stat -f
/mnt/test
By using 'hard' mount point means that cifs.ko will keep retrying
indefinitely, however we must allow the process to be killed otherwise
it would hang the system.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Cc: stable@vger.kernel.org
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This patch fixes a memory leak when doing a setxattr(2) in SMB2+.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
SMB1 mounting broke in commit 35e2cc1ba7
("cifs: Use correct packet length in SMB2_TRANSFORM header")
Fix it and also rename smb2_rqst_len to smb_rqst_len
to make it less unobvious that the function is also called from
CIFS/SMB1
Good job by Paulo reviewing and cleaning up Ronnie's original patch.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
Fixes: c713c8770f ("cifs: push rfc1002 generation down the stack")
We failed to validate signed data returned by the server because
__cifs_calc_signature() now expects to sign the actual data in iov but
we were also passing down the rfc1002 length.
Fix smb3_calc_signature() to calculate signature of rfc1002 length prior
to passing only the actual data iov[1-N] to __cifs_calc_signature(). In
addition, there are a few cases where no rfc1002 length is passed so we
make sure there's one (iov_len == 4).
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Fixes: c713c8770f ("cifs: push rfc1002 generation down the stack")
We failed to validate signed data returned by the server because
__cifs_calc_signature() now expects to sign the actual data in iov but
we were also passing down the rfc1002 length.
Fix smb3_calc_signature() to calculate signature of rfc1002 length prior
to passing only the actual data iov[1-N] to __cifs_calc_signature(). In
addition, there are a few cases where no rfc1002 length is passed so we
make sure there's one (iov_len == 4).
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
With protocol version 2.0 mounts we have seen crashes with corrupt mid
entries. Either the server->pending_mid_q list becomes corrupt with a
cyclic reference in one element or a mid object fetched by the
demultiplexer thread becomes overwritten during use.
Code review identified a race between the demultiplexer thread and the
request issuing thread. The demultiplexer thread seems to be written
with the assumption that it is the sole user of the mid object until
it calls the mid callback which either wakes the issuer task or
deletes the mid.
This assumption is not true because the issuer task can be woken up
earlier by a signal. If the demultiplexer thread has proceeded as far
as setting the mid_state to MID_RESPONSE_RECEIVED then the issuer
thread will happily end up calling cifs_delete_mid while the
demultiplexer thread still is using the mid object.
Inserting a delay in the cifs demultiplexer thread widens the race
window and makes reproduction of the race very easy:
if (server->large_buf)
buf = server->bigbuf;
+ usleep_range(500, 4000);
server->lstrp = jiffies;
To resolve this I think the proper solution involves putting a
reference count on the mid object. This patch makes sure that the
demultiplexer thread holds a reference until it has finished
processing the transaction.
Cc: stable@vger.kernel.org
Signed-off-by: Lars Persson <larper@axis.com>
Acked-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
It turns out that systemd has a bug: it wants to load the autofs module
early because of some initialization ordering with udev, and it doesn't
do that correctly. Everywhere else it does the proper "look up module
name" that does the proper alias resolution, but in that early code, it
just uses a hardcoded "autofs4" for the module name.
The result of that is that as of commit a2225d931f ("autofs: remove
left-over autofs4 stubs"), you get
systemd[1]: Failed to insert module 'autofs4': No such file or directory
in the system logs, and a lack of module loading. All this despite the
fact that we had very clearly marked 'autofs4' as an alias for this
module.
What's so ridiculous about this is that literally everything else does
the module alias handling correctly, including really old versions of
systemd (that just used 'modprobe' to do this), and even all the other
systemd module loading code.
Only that special systemd early module load code is broken, hardcoding
the module names for not just 'autofs4', but also "ipv6", "unix",
"ip_tables" and "virtio_rng". Very annoying.
Instead of creating an _additional_ separate compatibility 'autofs4'
module, just rely on the fact that everybody else gets this right, and
just call the module 'autofs4' for compatibility reasons, with 'autofs'
as the alias name.
That will allow the systemd people to fix their bugs, adding the proper
alias handling, and maybe even fix the name of the module to be just
"autofs" (so that they can _test_ the alias handling). And eventually,
we can revert this silly compatibility hack.
See also
https://github.com/systemd/systemd/issues/9501https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=902946
for the systemd bug reports upstream and in the Debian bug tracker
respectively.
Fixes: a2225d931f ("autofs: remove left-over autofs4 stubs")
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Reported-by: Michael Biebl <biebl@debian.org>
Cc: Ian Kent <raven@themaw.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use huge_ptep_get() to translate huge ptes to normal ptes so we can
check them with the huge_pte_* functions. Otherwise some architectures
will check the wrong values and will not wait for userspace to bring in
the memory.
Link: http://lkml.kernel.org/r/20180626132421.78084-1-frankja@linux.ibm.com
Fixes: 369cd2121b ("userfaultfd: hugetlbfs: userfaultfd_huge_must_wait for hugepmd ranges")
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch attempts to close a hole leading to a BUG seen with hot
removals during writes [1].
A block device (NVME namespace in this test case) is formatted to EXT4
without partitions. It's mounted and write I/O is run to a file, then
the device is hot removed from the slot. The superblock attempts to be
written to the drive which is no longer present.
The typical chain of events leading to the BUG:
ext4_commit_super()
__sync_dirty_buffer()
submit_bh()
submit_bh_wbc()
BUG_ON(!buffer_mapped(bh));
This fix checks for the superblock's buffer head being mapped prior to
syncing.
[1] https://www.spinics.net/lists/linux-ext4/msg56527.html
Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
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Merge tag 'for-4.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"We have a few regression fixes for qgroup rescan status tracking and
the vm_fault_t conversion that mixed up the error values"
* tag 'for-4.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix mount failure when qgroup rescan is in progress
Btrfs: fix regression in btrfs_page_mkwrite() from vm_fault_t conversion
btrfs: quota: Set rescan progress to (u64)-1 if we hit last leaf
Pull vfs fix from Al Viro:
"Followup to procfs-seq_file series this window"
This fixes a memory leak by making sure that proc seq files release any
private data on close. The 'proc_seq_open' has to be properly paired
with 'proc_seq_release' that releases the extra private data.
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
proc: add proc_seq_release
The poll() changes were not well thought out, and completely
unexplained. They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.
Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead. That gets rid of one of the new indirections.
But that doesn't fix the new complexity that is completely unwarranted
for the regular case. The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.
[ This revert is a revert of about 30 different commits, not reverted
individually because that would just be unnecessarily messy - Linus ]
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a power failure happens while the qgroup rescan kthread is running,
the next mount operation will always fail. This is because of a recent
regression that makes qgroup_rescan_init() incorrectly return -EINVAL
when we are mounting the filesystem (through btrfs_read_qgroup_config()).
This causes the -EINVAL error to be returned regardless of any qgroup
flags being set instead of returning the error only when neither of
the flags BTRFS_QGROUP_STATUS_FLAG_RESCAN nor BTRFS_QGROUP_STATUS_FLAG_ON
are set.
A test case for fstests follows up soon.
Fixes: 9593bf4967 ("btrfs: qgroup: show more meaningful qgroup_rescan_init error message")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The vm_fault_t conversion commit introduced a ret2 variable for tracking
the integer return values from internal btrfs functions. It was
sometimes returning VM_FAULT_LOCKED for pages that were actually invalid
and had been removed from the radix. Something like this:
ret2 = btrfs_delalloc_reserve_space() // returns zero on success
lock_page(page)
if (page->mapping != inode->i_mapping)
goto out_unlock;
...
out_unlock:
if (!ret2) {
...
return VM_FAULT_LOCKED;
}
This ends up triggering this WARNING in btrfs_destroy_inode()
WARN_ON(BTRFS_I(inode)->block_rsv.size);
xfstests generic/095 was able to reliably reproduce the errors.
Since out_unlock: is only used for errors, this fix moves it below the
if (!ret2) check we use to return VM_FAULT_LOCKED for success.
Fixes: a528a24150 (btrfs: change return type of btrfs_page_mkwrite to vm_fault_t)
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit ff3d27a048 ("btrfs: qgroup: Finish rescan when hit the last leaf
of extent tree") added a new exit for rescan finish.
However after finishing quota rescan, we set
fs_info->qgroup_rescan_progress to (u64)-1 before we exit through the
original exit path.
While we missed that assignment of (u64)-1 in the new exit path.
The end result is, the quota status item doesn't have the same value.
(-1 vs the last bytenr + 1)
Although it doesn't affect quota accounting, it's still better to keep
the original behavior.
Reported-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Fixes: ff3d27a048 ("btrfs: qgroup: Finish rescan when hit the last leaf of extent tree")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
kmemleak reported some memory leak on reading proc files. After adding
some debug lines, find that proc_seq_fops is using seq_release as
release handler, which won't handle the free of 'private' field of
seq_file, while in fact the open handler proc_seq_open could create
the private data with __seq_open_private when state_size is greater
than zero. So after reading files created with proc_create_seq_private,
such as /proc/timer_list and /proc/vmallocinfo, the private mem of a
seq_file is not freed. Fix it by adding the paired proc_seq_release
as the default release handler of proc_seq_ops instead of seq_release.
Fixes: 44414d82cf ("proc: introduce proc_create_seq_private")
Reviewed-by: Christoph Hellwig <hch@lst.de>
CC: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
- More metadata validation strengthening to prevent crashes.
- Fix extent offset overflow problem when insert_range on a 512b block fs
- Fix some off-by-one errors in the realtime fsmap code
- Fix some math errors in the default resblks calculation when free space
is low
- Fix a problem where stale page contents are exposed via mmap read
after a zero_range at eof
- Fix accounting problems with per-ag reservations causing statfs
reports to vary incorrectly
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Merge tag 'xfs-4.18-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fixes from Darrick Wong:
"Here are some patches for 4.18 to fix regressions, accounting
problems, overflow problems, and to strengthen metadata validation to
prevent corruption.
This series has been run through a full xfstests run over the weekend
and through a quick xfstests run against this morning's master, with
no major failures reported.
Changes since last update:
- more metadata validation strengthening to prevent crashes.
- fix extent offset overflow problem when insert_range on a 512b
block fs
- fix some off-by-one errors in the realtime fsmap code
- fix some math errors in the default resblks calculation when free
space is low
- fix a problem where stale page contents are exposed via mmap read
after a zero_range at eof
- fix accounting problems with per-ag reservations causing statfs
reports to vary incorrectly"
* tag 'xfs-4.18-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: fix fdblocks accounting w/ RMAPBT per-AG reservation
xfs: ensure post-EOF zeroing happens after zeroing part of a file
xfs: fix off-by-one error in xfs_rtalloc_query_range
xfs: fix uninitialized field in rtbitmap fsmap backend
xfs: recheck reflink state after grabbing ILOCK_SHARED for a write
xfs: don't allow insert-range to shift extents past the maximum offset
xfs: don't trip over negative free space in xfs_reserve_blocks
xfs: allow empty transactions while frozen
xfs: xfs_iflush_abort() can be called twice on cluster writeback failure
xfs: More robust inode extent count validation
xfs: simplify xfs_bmap_punch_delalloc_range
In any case, d_splice_alias() does not drop reference of original
dentry.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
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Merge tag 'for-4.18-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"Two regression fixes and an incorrect error value propagation fix from
'rename exchange'"
* tag 'for-4.18-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix return value on rename exchange failure
btrfs: fix invalid-free in btrfs_extent_same
Btrfs: fix physical offset reported by fiemap for inline extents
In __xfs_ag_resv_init we incorrectly calculate the amount by which to
decrease fdblocks when reserving blocks for the rmapbt. Because rmapbt
allocations do not decrease fdblocks, we must decrease fdblocks by the
entire size of the requested reservation in order to achieve our goal of
always having enough free blocks to satisfy an rmapbt expansion.
This is in contrast to the refcountbt/finobt, which /do/ subtract from
fdblocks whenever they allocate a block. For this allocation type we
preserve the existing behavior where we decrease fdblocks only by the
requested reservation minus the size of the existing tree.
This fixes the problem where the available block counts reported by
statfs change across a remount if there had been an rmapbt size change
since mount time.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
If a user asks us to zero_range part of a file, the end of the range is
EOF, and not aligned to a page boundary, invoke writeback of the EOF
page to ensure that the post-EOF part of the page is zeroed. This
ensures that we don't expose stale memory contents via mmap, if in a
clumsy manner.
Found by running generic/127 when it runs zero_range and mapread at EOF
one after the other.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
In commit 8ad560d256 ("xfs: strengthen rtalloc query range checks")
we strengthened the input parameter checks in the rtbitmap range query
function, but introduced an off-by-one error in the process. The call
to xfs_rtfind_forw deals with the high key being rextents, but we clamp
the high key to rextents - 1. This causes the returned results to stop
one block short of the end of the rtdev, which is incorrect.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Initialize the extent count field of the high key so that when we use
the high key to synthesize an 'unknown owner' record (i.e. used space
record) at the end of the queried range we have a field with which to
compute rm_blockcount. This is not strictly necessary because the
synthesizer never uses the rm_blockcount field, but we can shut up the
static code analysis anyway.
Coverity-id: 1437358
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Zorro Lang reports that generic/485 blows an assert on a filesystem with
512 byte blocks. The test tries to fallocate a post-eof extent at the
maximum file size and calls insert range to shift the extents right by
two blocks. On a 512b block filesystem this causes startoff to overflow
the 54-bit startoff field, leading to the assert.
Therefore, always check the rightmost extent to see if it would overflow
prior to invoking the insert range machinery.
Reported-by: zlang@redhat.com
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200137
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
If we somehow end up with a filesystem that has fewer free blocks than
the blocks set aside to avoid ENOSPC deadlocks, it's possible that the
free space calculation in xfs_reserve_blocks will spit out a negative
number (because percpu_counter_sum returns s64). We fail to notice
this negative number and set fdblks_delta to it. Now we increment
fdblocks(!) and the unsigned type of m_resblks means that we end up
setting a ridiculously huge m_resblks reservation.
Avoid this comedy of errors by detecting the negative free space and
returning -ENOSPC.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
In commit e89c041338 ("xfs: implement the GETFSMAP ioctl") we
created the ability to obtain empty transactions. These transactions
have no log or block reservations and therefore can't modify anything.
Since they're also NO_WRITECOUNT they can run while the fs is frozen,
so we don't need to WARN_ON about that usage.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
If we failed during a rename exchange operation after starting/joining a
transaction, we would end up replacing the return value, stored in the
local 'ret' variable, with the return value from btrfs_end_transaction().
So this could end up returning 0 (success) to user space despite the
operation having failed and aborted the transaction, because if there are
multiple tasks having a reference on the transaction at the time
btrfs_end_transaction() is called by the rename exchange, that function
returns 0 (otherwise it returns -EIO and not the original error value).
So fix this by not overwriting the return value on error after getting
a transaction handle.
Fixes: cdd1fedf82 ("btrfs: add support for RENAME_EXCHANGE and RENAME_WHITEOUT")
CC: stable@vger.kernel.org # 4.9+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
