One can use btrfs-corrupt-block to hit BUG_ON() in merge_bio(),
thus this aims to stop anyone to panic the whole system by using
their btrfs.
Since the error in merge_bio can only come from __btrfs_map_block()
when chunk tree mapping has something insane and __btrfs_map_block()
has already had printed the reason, we can just return errors in
merge_bio.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
BTRFS is using a variety of slab caches to satisfy internal needs.
Those slab caches are always allocated with the SLAB_RECLAIM_ACCOUNT,
meaning allocations from the caches are going to be accounted as
SReclaimable. At the same time btrfs is not registering any shrinkers
whatsoever, thus preventing memory from the slabs to be shrunk. This
means those caches are not in fact reclaimable.
To fix this remove the SLAB_RECLAIM_ACCOUNT on all caches apart from the
inode cache, since this one is being freed by the generic VFS super_block
shrinker. Also set the transaction related caches as SLAB_TEMPORARY,
to better document the lifetime of the objects (it just translates
to SLAB_RECLAIM_ACCOUNT).
Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
size contains the value returned by posix_acl_from_xattr(), which
returns -ERANGE, -ENODATA, zero, or an integer greater than zero. So
replace -ENOENT by -ERANGE.
Signed-off-by: Salah Triki <salah.triki@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The code flow in btrfs_new_inode allows for btrfs_evict_inode to be
called with not fully initialised inode (e.g. ->root member not
being set). This can happen when btrfs_set_inode_index in
btrfs_new_inode fails, which in turn would call iput for the newly
allocated inode. This in turn leads to vfs calling into btrfs_evict_inode.
This leads to null pointer dereference. To handle this situation check whether
the passed inode has root set and just free it in case it doesn't.
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We use read_node_slot() to read btree node and it has two cases,
a) slot is out of range, which means 'no such entry'
b) we fail to read the block, due to checksum fails or corrupted
content or not with uptodate flag.
But we're returning NULL in both cases, this makes it return -ENOENT
in case a) and return -EIO in case b), and this fixes its callers
as well as btrfs_search_forward() 's caller to catch the new errors.
The problem is reported by Peter Becker, and I can manage to
hit the same BUG_ON by mounting my fuzz image.
Reported-by: Peter Becker <floyd.net@gmail.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With btrfs-corrupt-block, one can set btree node/leaf's field, if
we assign a negative value to node/leaf, we can get various hangs,
eg. if extent_root's nritems is -2ULL, then we get stuck in
btrfs_read_block_groups() because it has a while loop and
btrfs_search_slot() on extent_root will always return the first
child.
This lets us know what's happening and returns a EINVAL to callers
instead of returning the first item.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With btrfs-corrupt-block, one can drop one chunk item and mounting
will end up with a panic in btrfs_full_stripe_len().
This doesn't not remove the BUG_ON, but instead checks it a bit
earlier when we find the block group item.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull timer updates from Thomas Gleixner:
"This update provides the following changes:
- The rework of the timer wheel which addresses the shortcomings of
the current wheel (cascading, slow search for next expiring timer,
etc). That's the first major change of the wheel in almost 20
years since Finn implemted it.
- A large overhaul of the clocksource drivers init functions to
consolidate the Device Tree initialization
- Some more Y2038 updates
- A capability fix for timerfd
- Yet another clock chip driver
- The usual pile of updates, comment improvements all over the place"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (130 commits)
tick/nohz: Optimize nohz idle enter
clockevents: Make clockevents_subsys static
clocksource/drivers/time-armada-370-xp: Fix return value check
timers: Implement optimization for same expiry time in mod_timer()
timers: Split out index calculation
timers: Only wake softirq if necessary
timers: Forward the wheel clock whenever possible
timers/nohz: Remove pointless tick_nohz_kick_tick() function
timers: Optimize collect_expired_timers() for NOHZ
timers: Move __run_timers() function
timers: Remove set_timer_slack() leftovers
timers: Switch to a non-cascading wheel
timers: Reduce the CPU index space to 256k
timers: Give a few structs and members proper names
hlist: Add hlist_is_singular_node() helper
signals: Use hrtimer for sigtimedwait()
timers: Remove the deprecated mod_timer_pinned() API
timers, net/ipv4/inet: Initialize connection request timers as pinned
timers, drivers/tty/mips_ejtag: Initialize the poll timer as pinned
timers, drivers/tty/metag_da: Initialize the poll timer as pinned
...
Pull x86 mm updates from Ingo Molnar:
"Various x86 low level modifications:
- preparatory work to support virtually mapped kernel stacks (Andy
Lutomirski)
- support for 64-bit __get_user() on 32-bit kernels (Benjamin
LaHaise)
- (involved) workaround for Knights Landing CPU erratum (Dave Hansen)
- MPX enhancements (Dave Hansen)
- mremap() extension to allow remapping of the special VDSO vma, for
purposes of user level context save/restore (Dmitry Safonov)
- hweight and entry code cleanups (Borislav Petkov)
- bitops code generation optimizations and cleanups with modern GCC
(H. Peter Anvin)
- syscall entry code optimizations (Paolo Bonzini)"
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (43 commits)
x86/mm/cpa: Add missing comment in populate_pdg()
x86/mm/cpa: Fix populate_pgd(): Stop trying to deallocate failed PUDs
x86/syscalls: Add compat_sys_preadv64v2/compat_sys_pwritev64v2
x86/smp: Remove unnecessary initialization of thread_info::cpu
x86/smp: Remove stack_smp_processor_id()
x86/uaccess: Move thread_info::addr_limit to thread_struct
x86/dumpstack: Rename thread_struct::sig_on_uaccess_error to sig_on_uaccess_err
x86/uaccess: Move thread_info::uaccess_err and thread_info::sig_on_uaccess_err to thread_struct
x86/dumpstack: When OOPSing, rewind the stack before do_exit()
x86/mm/64: In vmalloc_fault(), use CR3 instead of current->active_mm
x86/dumpstack/64: Handle faults when printing the "Stack: " part of an OOPS
x86/dumpstack: Try harder to get a call trace on stack overflow
x86/mm: Remove kernel_unmap_pages_in_pgd() and efi_cleanup_page_tables()
x86/mm/cpa: In populate_pgd(), don't set the PGD entry until it's populated
x86/mm/hotplug: Don't remove PGD entries in remove_pagetable()
x86/mm: Use pte_none() to test for empty PTE
x86/mm: Disallow running with 32-bit PTEs to work around erratum
x86/mm: Ignore A/D bits in pte/pmd/pud_none()
x86/mm: Move swap offset/type up in PTE to work around erratum
x86/entry: Inline enter_from_user_mode()
...
Relocs are fixed up in place in user space memory. The appropriate
accessors are required for this code to work with an active MMU.
The architecture specific handlers flat_get_addr_from_rp() and
flat_put_addr_at_rp() for ARM and M68K are adjusted with separate
patches. SuperH and Xtensa are left out as they doesn't implement
__get_user_unaligned() and __put_user_unaligned() yet. The other
architectures that use BFLT don't have any MMU.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
In addition to better code clarity, this brings proper usage of
user memory accessors everywhere the stack is touched. This is essential
for making this work on MMU systems.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
This gets rid of the rather ugly, open coded and suboptimal copy code.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
This copying of arguments and environment is common to both NOMMU
binary formats we support. Let's make the elf_fdpic version available
to the flat format as well.
While at it, improve the code a bit not to copy below the actual
data area.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Remove excessive casts, do some code grouping, fix most important
checkpatch.pl complaints, etc.
No functional changes.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Pull char/misc driver updates from Greg KH:
"Here is the big char/misc driver update for 4.8-rc1.
Not a lot of stuff, but it's all over the place, full details are in
the shortlog. All of these have been in linux-next with no reported
issues for a while"
* tag 'char-misc-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (49 commits)
lkdtm: silence warnings about function declarations
lkdtm: hide unused functions
intel_th: pci: Add Kaby Lake PCH-H support
intel_th: Fix a deadlock in modprobing
dsp56k: prevent a harmless underflow
chardev: add missing line break in pr_warn
lkdtm: use struct arrays instead of enums
lkdtm: move jprobe entry points to start of source
lkdtm: reorganize module paramaters
lkdtm: rename globals for clarity
lkdtm: rename "count" to "crash_count"
lkdtm: remove intentional off-by-one array access
lkdtm: split remaining logic bug tests to separate file
lkdtm: split heap corruption tests to separate file
lkdtm: split memory permissions tests to separate file
lkdtm: split usercopy tests to separate file
lkdtm: drop "alloc_size" parameter
lkdtm: add usercopy test for blocking kernel text
extcon: adc-jack: add suspend/resume support
extcon: add missing of_node_put after calling of_parse_phandle
...
Pull gfs2 updates from Bob Peterson:
"We've got ten patches this time, half of which are related to a
plethora of nasty outcomes when inodes are transitioned from the
unlinked state to the free state. Small file systems are particularly
vulnerable to these problems, and it can manifest as mainly hangs, but
also file system corruption. The patches have been tested for
literally many weeks, with a very gruelling test, so I have a high
level of confidence.
- Andreas Gruenbacher wrote a series of five patches for various
lockups during the transition of inodes from unlinked to free.
The main patch is titled "Fix gfs2_lookup_by_inum lock inversion"
and the other four are support and cleanup patches related to that.
- Ben Marzinski contributed two patches with regard to a recreatable
problem when gfs2 tries to write a page to a file that is being
truncated, resulting in a BUG() in gfs2_remove_from_journal.
Note that Ben had to export vfs function __block_write_full_page to
get this to work properly. It's been posted a long time and he
talked to various VFS people about it, and nobody seemed to mind.
- I contributed 3 patches:
o The first one fixes a memory corruptor: a race in which one
process can overwrite the gl_object pointer set by another
process, causing kernel panic and other symptoms.
o The second patch fixes another race that resulted in a
false-positive BUG_ON. This occurred when resource group
reservations were freed by one process while another process
was trying to grab a new reservation in the same resource
group.
o The third patch fixes a problem with doing journal replay when
the journals are not all the same size"
* tag 'gfs2-4.7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
GFS2: Fix gfs2_replay_incr_blk for multiple journal sizes
GFS2: Check rs_free with rd_rsspin protection
gfs2: writeout truncated pages
fs: export __block_write_full_page
gfs2: Lock holder cleanup
gfs2: Large-filesystem fix for 32-bit systems
gfs2: Get rid of gfs2_ilookup
gfs2: Fix gfs2_lookup_by_inum lock inversion
gfs2: Initialize iopen glock holder for new inodes
GFS2: don't set rgrp gl_object until it's inserted into rgrp tree
Replace it with a test for whether or not the sent a stateid in violation
of what we asked for.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We triggered soft-lockup under stress test which
open/access/write/close one file concurrently on more than
five different CPUs:
WARN: soft lockup - CPU#0 stuck for 11s! [who:30631]
...
[<ffffffc0003986f8>] dput+0x100/0x298
[<ffffffc00038c2dc>] terminate_walk+0x4c/0x60
[<ffffffc00038f56c>] path_lookupat+0x5cc/0x7a8
[<ffffffc00038f780>] filename_lookup+0x38/0xf0
[<ffffffc000391180>] user_path_at_empty+0x78/0xd0
[<ffffffc0003911f4>] user_path_at+0x1c/0x28
[<ffffffc00037d4fc>] SyS_faccessat+0xb4/0x230
->d_lock trylock may failed many times because of concurrently
operations, and dput() may execute a long time.
Fix this by replacing cpu_relax() with cond_resched().
dput() used to be sleepable, so make it sleepable again
should be safe.
Cc: <stable@vger.kernel.org>
Signed-off-by: Wei Fang <fangwei1@huawei.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
commit 6c51e513a3 ("lookup_dcache(): lift d_alloc() into callers")
removed the need_lookup argument from lookup_dcache(), but the
comment was forgotten. Also it no longer allocates a new dentry
if nothing was found.
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
...instead of splitting the initialisation over init_lseg() and
pnfs_layout_process().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the server changed the layout stateid's "other" field, then
we should treat the old layout as being completely gone. In that
case, we want to clear the metadata such as scheduled layoutreturns.
Do this by calling pnfs_mark_layout_stateid_invalid().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When determining which layout segments to return, we do want
pnfs_mark_matching_lsegs_return to check that they match the layout
sequence id. This ensures that we don't waste time if the server
is replaying a layout recall that has already been satisfied.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
In cases where we need to send a layoutreturn in order to propagate
an error, we should not tie that to a specific layout stateid.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When we return NFS_OK to the CB_LAYOUTRECALL, we are required to
send a layoutreturn that "completes" that layout recall request, using
the correct stateid.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We want to evaluate in this order:
If the client holds no layout for this inode, then return
NFS4ERR_NOMATCHING_LAYOUT; it probably forgot the layout.
If the client finds the inode among the list of layouts, but the corresponding
stateid has not yet been initialised, then return NFS4ERR_DELAY to ask the
server to retry once the outstanding LAYOUTGET is complete.
If the current layout stateid's "other" field does not match the recalled
stateid, return NFS4ERR_BAD_STATEID.
If already processing a layout recall with a newer stateid, return
NFS4ERR_OLD_STATEID. This can only happens for servers that are
non-compliant with the NFSv4.1 protocol.
If already processing a layout recall with an older stateid, return
NFS4ERR_DELAY to ask the server to retry once the outstanding
LAYOUTRETURN is complete. Again, this is technically incompliant with
the NFSv4.1 protocol.
If the current layout sequence id is newer than the recalled stateid's
sequence id, return NFS4ERR_OLD_STATEID. This too implies protocol
non-compliance.
If the current layout sequence id is older than the recalled stateid's
sequence id+1, return NFS4ERR_DELAY.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Currently, pnfs_set_layout_stateid() will update the layout sequence
id barrier only if the stateid itself is newer than the current
layout stateid. However in a situation where multiple LAYOUTGET calls
and a LAYOUTRETURN raced, it is entirely possible for one of the
LAYOUTGET to set the current stateid to something newer than the
LAYOUTRETURN that needs to set the barrier.
The fix is to allow the "update_barrier" flag to force a check as to
whether or not the barrier needs to be updated.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the layout stateid is invalid, then pnfs_set_layout_stateid() must
always initialise it.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Ensure that we don't carry over layoutreturn info from a previous
incarnation of this layout.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Seth Forshee reported a mount regression in nfs autmounts
with "fs: Add user namespace member to struct super_block".
It turns out that the assumption that current->cred is something
reasonable during mount while necessary to improve support of
unprivileged mounts is wrong in the automount path.
To fix the existing filesystems override current->cred with the
init_cred before calling d_automount and restore current->cred after
d_automount completes.
To support unprivileged mounts would require a more nuanced cred
selection, so fail on unprivileged mounts for the time being. As none
of the filesystems that currently set FS_USERNS_MOUNT implement
d_automount this check is only good for preventing future problems.
Fixes: 6e4eab577a ("fs: Add user namespace member to struct super_block")
Tested-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Pull overlayfs fixes from Miklos Szeredi:
"This contains a fix for a potential crash/corruption issue and another
where the suid/sgid bits weren't cleared on write"
* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
ovl: verify upper dentry in ovl_remove_and_whiteout()
ovl: Copy up underlying inode's ->i_mode to overlay inode
ovl: handle ATTR_KILL*
