Pull block fixes from Jens Axboe:
"Four smaller fixes for the current series. This contains:
- A fix for clones of discard bio's, that can cause data corruption.
From Martin.
- A fix for null_blk, where in certain queue modes it could access a
request after it had been freed. From Mike Krinkin.
- An error handling leak fix for blkcg, from Tejun.
- Also from Tejun, export of the functions that a file system needs
to implement cgroup writeback support"
* 'for-linus' of git://git.kernel.dk/linux-block:
block: Do a full clone when splitting discard bios
block: export bio_associate_*() and wbc_account_io()
blkcg: fix gendisk reference leak in blkg_conf_prep()
null_blk: fix use-after-free problem
Pull namespace fixes from Eric Biederman:
"While reading through the code of detach_mounts I realized the code
was slightly off. Testing it revealed two buggy corner cases that can
send the code of detach_mounts into an infinite loop.
Fixing the code to do the right thing removes the possibility of these
user triggered infinite loops in the code"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
mnt: In detach_mounts detach the appropriate unmounted mount
mnt: Clarify and correct the disconnect logic in umount_tree
bio_associate_blkcg(), bio_associate_current() and wbc_account_io()
are used to implement cgroup writeback support for filesystems and
thus need to be exported. Export them.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jens Axboe <axboe@fb.com>
The handling of in detach_mounts of unmounted but connected mounts is
buggy and can lead to an infinite loop.
Correct the handling of unmounted mounts in detach_mount. When the
mountpoint of an unmounted but connected mount is connected to a
dentry, and that dentry is deleted we need to disconnect that mount
from the parent mount and the deleted dentry.
Nothing changes for the unmounted and connected children. They can be
safely ignored.
Cc: stable@vger.kernel.org
Fixes: ce07d891a0 mnt: Honor MNT_LOCKED when detaching mounts
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
rmdir mntpoint will result in an infinite loop when there is
a mount locked on the mountpoint in another mount namespace.
This is because the logic to test to see if a mount should
be disconnected in umount_tree is buggy.
Move the logic to decide if a mount should remain connected to
it's mountpoint into it's own function disconnect_mount so that
clarity of expression instead of terseness of expression becomes
a virtue.
When the conditions where it is invalid to leave a mount connected
are first ruled out, the logic for deciding if a mount should
be disconnected becomes much clearer and simpler.
Fixes: e0c9c0afd2 mnt: Update detach_mounts to leave mounts connected
Fixes: ce07d891a0 mnt: Honor MNT_LOCKED when detaching mounts
Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This reverts commit a2673b6e04.
Kinglong Mee reports a memory leak with that patch, and Jan Kara confirms:
"Thanks for report! You are right that my patch introduces a race
between fsnotify kthread and fsnotify_destroy_group() which can result
in leaking inotify event on group destruction.
I haven't yet decided whether the right fix is not to queue events for
dying notification group (as that is pointless anyway) or whether we
should just fix the original problem differently... Whenever I look
at fsnotify code mark handling I get lost in the maze of locks, lists,
and subtle differences between how different notification systems
handle notification marks :( I'll think about it over night"
and after thinking about it, Jan says:
"OK, I have looked into the code some more and I found another
relatively simple way of fixing the original oops. It will be IMHO
better than trying to fixup this issue which has more potential for
breakage. I'll ask Linus to revert the fsnotify fix he already merged
and send a new fix"
Reported-by: Kinglong Mee <kinglongmee@gmail.com>
Requested-by: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull UDF fix from Jan Kara:
"A fix for UDF corruption when certain disk-format feature is enabled"
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
udf: Don't corrupt unalloc spacetable when writing it
Pull x86 fixes from Ingo Molnar:
"Two families of fixes:
- Fix an FPU context related boot crash on newer x86 hardware with
larger context sizes than what most people test. To fix this
without ugly kludges or extensive reverts we had to touch core task
allocator, to allow x86 to determine the task size dynamically, at
boot time.
I've tested it on a number of x86 platforms, and I cross-built it
to a handful of architectures:
(warns) (warns)
testing x86-64: -git: pass ( 0), -tip: pass ( 0)
testing x86-32: -git: pass ( 0), -tip: pass ( 0)
testing arm: -git: pass ( 1359), -tip: pass ( 1359)
testing cris: -git: pass ( 1031), -tip: pass ( 1031)
testing m32r: -git: pass ( 1135), -tip: pass ( 1135)
testing m68k: -git: pass ( 1471), -tip: pass ( 1471)
testing mips: -git: pass ( 1162), -tip: pass ( 1162)
testing mn10300: -git: pass ( 1058), -tip: pass ( 1058)
testing parisc: -git: pass ( 1846), -tip: pass ( 1846)
testing sparc: -git: pass ( 1185), -tip: pass ( 1185)
... so I hope the cross-arch impact 'none', as intended.
(by Dave Hansen)
- Fix various NMI handling related bugs unearthed by the big asm code
rewrite and generally make the NMI code more robust and more
maintainable while at it. These changes are a bit late in the
cycle, I hope they are still acceptable.
(by Andy Lutomirski)"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it on x86
x86/fpu, sched: Dynamically allocate 'struct fpu'
x86/entry/64, x86/nmi/64: Add CONFIG_DEBUG_ENTRY NMI testing code
x86/nmi/64: Make the "NMI executing" variable more consistent
x86/nmi/64: Minor asm simplification
x86/nmi/64: Use DF to avoid userspace RSP confusing nested NMI detection
x86/nmi/64: Reorder nested NMI checks
x86/nmi/64: Improve nested NMI comments
x86/nmi/64: Switch stacks on userspace NMI entry
x86/nmi/64: Remove asm code that saves CR2
x86/nmi: Enable nested do_nmi() handling for 64-bit kernels
Merge fixes from Andrew Morton:
"25 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (25 commits)
lib/decompress: set the compressor name to NULL on error
mm/cma_debug: correct size input to bitmap function
mm/cma_debug: fix debugging alloc/free interface
mm/page_owner: set correct gfp_mask on page_owner
mm/page_owner: fix possible access violation
fsnotify: fix oops in fsnotify_clear_marks_by_group_flags()
/proc/$PID/cmdline: fixup empty ARGV case
dma-debug: skip debug_dma_assert_idle() when disabled
hexdump: fix for non-aligned buffers
checkpatch: fix long line messages about patch context
mm: clean up per architecture MM hook header files
MAINTAINERS: uclinux-h8-devel is moderated for non-subscribers
mailmap: update Sudeep Holla's email id
Update Viresh Kumar's email address
mm, meminit: suppress unused memory variable warning
configfs: fix kernel infoleak through user-controlled format string
include, lib: add __printf attributes to several function prototypes
s390/hugetlb: add hugepages_supported define
mm: hugetlb: allow hugepages_supported to be architecture specific
revert "s390/mm: make hugepages_supported a boot time decision"
...
Pull btrfs fixes from Chris Mason:
"These are all from Filipe, and cover a few problems we've had reported
on the list recently (along with ones he found on his own)"
* 'for-linus-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix file corruption after cloning inline extents
Btrfs: fix order by which delayed references are run
Btrfs: fix list transaction->pending_ordered corruption
Btrfs: fix memory leak in the extent_same ioctl
Btrfs: fix shrinking truncate when the no_holes feature is enabled
fsnotify_clear_marks_by_group_flags() can race with
fsnotify_destroy_marks() so when fsnotify_destroy_mark_locked() drops
mark_mutex, a mark from the list iterated by
fsnotify_clear_marks_by_group_flags() can be freed and we dereference free
memory in the loop there.
Fix the problem by keeping mark_mutex held in
fsnotify_destroy_mark_locked(). The reason why we drop that mutex is that
we need to call a ->freeing_mark() callback which may acquire mark_mutex
again. To avoid this and similar lock inversion issues, we move the call
to ->freeing_mark() callback to the kthread destroying the mark.
Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: Ashish Sangwan <a.sangwan@samsung.com>
Suggested-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
/proc/*/cmdline code checks if it should look at ENVP area by checking
last byte of ARGV area:
rv = access_remote_vm(mm, arg_end - 1, &c, 1, 0);
if (rv <= 0)
goto out_free_page;
If ARGV is somehow made empty (by doing execve(..., NULL, ...) or
manually setting ->arg_start and ->arg_end to equal values), the decision
will be based on byte which doesn't even belong to ARGV/ENVP.
So, quickly check if ARGV area is empty and report 0 to match previous
behaviour.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some modules call config_item_init_type_name() and config_group_init_type_name()
with parameter "name" directly controlled by userspace. These two
functions call config_item_set_name() with this name used as a format
string, which can be used to leak information such as content of the
stack to userspace.
For example, make_netconsole_target() in netconsole module calls
config_item_init_type_name() with the name of a newly-created directory.
This means that the following commands give some unexpected output, with
configfs mounted in /sys/kernel/config/ and on a system with a
configured eth0 ethernet interface:
# modprobe netconsole
# mkdir /sys/kernel/config/netconsole/target_%lx
# echo eth0 > /sys/kernel/config/netconsole/target_%lx/dev_name
# echo 1 > /sys/kernel/config/netconsole/target_%lx/enabled
# echo eth0 > /sys/kernel/config/netconsole/target_%lx/dev_name
# dmesg |tail -n1
[ 142.697668] netconsole: target (target_ffffffffc0ae8080) is
enabled, disable to update parameters
The directory name is correct but %lx has been interpreted in the
internal item name, displayed here in the error message used by
store_dev_name() in drivers/net/netconsole.c.
To fix this, update every caller of config_item_set_name to use "%s"
when operating on untrusted input.
This issue was found using -Wformat-security gcc flag, once a __printf
attribute has been added to config_item_set_name().
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <balbi@ti.com>
Acked-by: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The purpose of the option was documented in
Documentation/filesystems/proc.txt but the help text was missing.
Add small help text that also points to the documentation.
Signed-off-by: Iago López Galeiras <iago@endocode.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull jfs fixes from David Kleikamp:
"A couple trivial fixes and an error path fix"
* tag 'jfs-4.2' of git://github.com/kleikamp/linux-shaggy:
jfs: clean up jfs_rename and fix out of order unlock
jfs: fix indentation on if statement
jfs: removed a prohibited space after opening parenthesis
Pull file locking updates from Jeff Layton:
"I had thought that I was going to get away without a pull request this
cycle. There was a NFSv4 file locking problem that cropped up that I
tried to fix in the NFSv4 code alone, but that fix has turned out to
be problematic. These patches fix this in the correct way.
Note that this touches some NFSv4 code as well. Ordinarily I'd wait
for Trond to ACK this, but he's on holiday right now and the bug is
rather nasty. So I suggest we merge this and if he raises issues with
it we can sort it out when he gets back"
Acked-by: Bruce Fields <bfields@fieldses.org>
Acked-by: Dan Williams <dan.j.williams@intel.com>
[ +1 to this series fixing a 100% reproducible slab corruption +
general protection fault in my nfs-root test environment. - Dan ]
Acked-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* tag 'locks-v4.2-1' of git://git.samba.org/jlayton/linux:
locks: inline posix_lock_file_wait and flock_lock_file_wait
nfs4: have do_vfs_lock take an inode pointer
locks: new helpers - flock_lock_inode_wait and posix_lock_inode_wait
locks: have flock_lock_file take an inode pointer instead of a filp
Revert "nfs: take extra reference to fl->fl_file when running a LOCKU operation"
The end of jfs_rename(), which is also used by the error paths,
included a call to IWRITE_UNLOCK(new_ip) after labels out1, out2
and out3. If we come in through these labels, IWRITE_LOCK() has not
been called yet.
In moving that call to the correct spot, I also moved some
exceptional truncate code earlier as well, since the early error
paths don't need to deal with it, and I renamed out4: to out_tx: so
a future patch by Jan Kara doesn't need to deal with renumbering or
confusing out-of-order labels.
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Using the clone ioctl (or extent_same ioctl, which calls the same extent
cloning function as well) we end up allowing copy an inline extent from
the source file into a non-zero offset of the destination file. This is
something not expected and that the btrfs code is not prepared to deal
with - all inline extents must be at a file offset equals to 0.
For example, the following excerpt of a test case for fstests triggers
a crash/BUG_ON() on a write operation after an inline extent is cloned
into a non-zero offset:
_scratch_mkfs >>$seqres.full 2>&1
_scratch_mount
# Create our test files. File foo has the same 2K of data at offset 4K
# as file bar has at its offset 0.
$XFS_IO_PROG -f -s -c "pwrite -S 0xaa 0 4K" \
-c "pwrite -S 0xbb 4k 2K" \
-c "pwrite -S 0xcc 8K 4K" \
$SCRATCH_MNT/foo | _filter_xfs_io
# File bar consists of a single inline extent (2K size).
$XFS_IO_PROG -f -s -c "pwrite -S 0xbb 0 2K" \
$SCRATCH_MNT/bar | _filter_xfs_io
# Now call the clone ioctl to clone the extent of file bar into file
# foo at its offset 4K. This made file foo have an inline extent at
# offset 4K, something which the btrfs code can not deal with in future
# IO operations because all inline extents are supposed to start at an
# offset of 0, resulting in all sorts of chaos.
# So here we validate that clone ioctl returns an EOPNOTSUPP, which is
# what it returns for other cases dealing with inlined extents.
$CLONER_PROG -s 0 -d $((4 * 1024)) -l $((2 * 1024)) \
$SCRATCH_MNT/bar $SCRATCH_MNT/foo
# Because of the inline extent at offset 4K, the following write made
# the kernel crash with a BUG_ON().
$XFS_IO_PROG -c "pwrite -S 0xdd 6K 2K" $SCRATCH_MNT/foo | _filter_xfs_io
status=0
exit
The stack trace of the BUG_ON() triggered by the last write is:
[152154.035903] ------------[ cut here ]------------
[152154.036424] kernel BUG at mm/page-writeback.c:2286!
[152154.036424] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[152154.036424] Modules linked in: btrfs dm_flakey dm_mod crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop fuse parport_pc acpi_cpu$
[152154.036424] CPU: 2 PID: 17873 Comm: xfs_io Tainted: G W 4.1.0-rc6-btrfs-next-11+ #2
[152154.036424] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.1-0-g4adadbd-20150316_085822-nilsson.home.kraxel.org 04/01/2014
[152154.036424] task: ffff880429f70990 ti: ffff880429efc000 task.ti: ffff880429efc000
[152154.036424] RIP: 0010:[<ffffffff8111a9d5>] [<ffffffff8111a9d5>] clear_page_dirty_for_io+0x1e/0x90
[152154.036424] RSP: 0018:ffff880429effc68 EFLAGS: 00010246
[152154.036424] RAX: 0200000000000806 RBX: ffffea0006a6d8f0 RCX: 0000000000000001
[152154.036424] RDX: 0000000000000000 RSI: ffffffff81155d1b RDI: ffffea0006a6d8f0
[152154.036424] RBP: ffff880429effc78 R08: ffff8801ce389fe0 R09: 0000000000000001
[152154.036424] R10: 0000000000002000 R11: ffffffffffffffff R12: ffff8800200dce68
[152154.036424] R13: 0000000000000000 R14: ffff8800200dcc88 R15: ffff8803d5736d80
[152154.036424] FS: 00007fbf119f6700(0000) GS:ffff88043d280000(0000) knlGS:0000000000000000
[152154.036424] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[152154.036424] CR2: 0000000001bdc000 CR3: 00000003aa555000 CR4: 00000000000006e0
[152154.036424] Stack:
[152154.036424] ffff8803d5736d80 0000000000000001 ffff880429effcd8 ffffffffa04e97c1
[152154.036424] ffff880429effd68 ffff880429effd60 0000000000000001 ffff8800200dc9c8
[152154.036424] 0000000000000001 ffff8800200dcc88 0000000000000000 0000000000001000
[152154.036424] Call Trace:
[152154.036424] [<ffffffffa04e97c1>] lock_and_cleanup_extent_if_need+0x147/0x18d [btrfs]
[152154.036424] [<ffffffffa04ea82c>] __btrfs_buffered_write+0x245/0x4c8 [btrfs]
[152154.036424] [<ffffffffa04ed14b>] ? btrfs_file_write_iter+0x150/0x3e0 [btrfs]
[152154.036424] [<ffffffffa04ed15a>] ? btrfs_file_write_iter+0x15f/0x3e0 [btrfs]
[152154.036424] [<ffffffffa04ed2c7>] btrfs_file_write_iter+0x2cc/0x3e0 [btrfs]
[152154.036424] [<ffffffff81165a4a>] __vfs_write+0x7c/0xa5
[152154.036424] [<ffffffff81165f89>] vfs_write+0xa0/0xe4
[152154.036424] [<ffffffff81166855>] SyS_pwrite64+0x64/0x82
[152154.036424] [<ffffffff81465197>] system_call_fastpath+0x12/0x6f
[152154.036424] Code: 48 89 c7 e8 0f ff ff ff 5b 41 5c 5d c3 0f 1f 44 00 00 55 48 89 e5 41 54 53 48 89 fb e8 ae ef 00 00 49 89 c4 48 8b 03 a8 01 75 02 <0f> 0b 4d 85 e4 74 59 49 8b 3c 2$
[152154.036424] RIP [<ffffffff8111a9d5>] clear_page_dirty_for_io+0x1e/0x90
[152154.036424] RSP <ffff880429effc68>
[152154.242621] ---[ end trace e3d3376b23a57041 ]---
Fix this by returning the error EOPNOTSUPP if an attempt to copy an
inline extent into a non-zero offset happens, just like what is done for
other scenarios that would require copying/splitting inline extents,
which were introduced by the following commits:
00fdf13a2e ("Btrfs: fix a crash of clone with inline extents's split")
3f9e3df8da ("btrfs: replace error code from btrfs_drop_extents")
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
They just call file_inode and then the corresponding *_inode_file_wait
function. Just make them static inlines instead.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Now that we have file locking helpers that can deal with an inode
instead of a filp, we can change the NFSv4 locking code to use that
instead.
This should fix the case where we have a filp that is closed while flock
or OFD locks are set on it, and the task is signaled so that it doesn't
wait for the LOCKU reply to come in before the filp is freed. At that
point we can end up with a use-after-free with the current code, which
relies on dereferencing the fl_file in the lock request.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reviewed-by: "J. Bruce Fields" <bfields@fieldses.org>
Tested-by: "J. Bruce Fields" <bfields@fieldses.org>
...and rename it to better describe how it works.
In order to fix a use-after-free in NFS, we need to be able to remove
locks from an inode after the filp associated with them may have already
been freed. flock_lock_file already only dereferences the filp to get to
the inode, so just change it so the callers do that.
All of the callers already pass in a lock request that has the fl_file
set properly, so we don't need to pass it in individually. With that
change it now only dereferences the filp to get to the inode, so just
push that out to the callers.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reviewed-by: "J. Bruce Fields" <bfields@fieldses.org>
Tested-by: "J. Bruce Fields" <bfields@fieldses.org>
This reverts commit db2efec0ca.
William reported that he was seeing instability with this patch, which
is likely due to the fact that it can cause the kernel to take a new
reference to a filp after the last reference has already been put.
Revert this patch for now, as we'll need to fix this in another way.
Cc: stable@vger.kernel.org
Reported-by: William Dauchy <william@gandi.net>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reviewed-by: "J. Bruce Fields" <bfields@fieldses.org>
Tested-by: "J. Bruce Fields" <bfields@fieldses.org>
