commit 76ae281f63 upstream.
A race window in configfs, it starts from one dentry is UNHASHED and end
before configfs_d_iput is called. In this window, if a lookup happen,
since the original dentry was UNHASHED, so a new dentry will be
allocated, and then in configfs_attach_attr(), sd->s_dentry will be
updated to the new dentry. Then in configfs_d_iput(),
BUG_ON(sd->s_dentry != dentry) will be triggered and system panic.
sys_open: sys_close:
... fput
dput
dentry_kill
__d_drop <--- dentry unhashed here,
but sd->dentry still point
to this dentry.
lookup_real
configfs_lookup
configfs_attach_attr---> update sd->s_dentry
to new allocated dentry here.
d_kill
configfs_d_iput <--- BUG_ON(sd->s_dentry != dentry)
triggered here.
To fix it, change configfs_d_iput to not update sd->s_dentry if
sd->s_count > 2, that means there are another dentry is using the sd
beside the one that is going to be put. Use configfs_dirent_lock in
configfs_attach_attr to sync with configfs_d_iput.
With the following steps, you can reproduce the bug.
1. enable ocfs2, this will mount configfs at /sys/kernel/config and
fill configure in it.
2. run the following script.
while [ 1 ]; do cat /sys/kernel/config/cluster/$your_cluster_name/idle_timeout_ms > /dev/null; done &
while [ 1 ]; do cat /sys/kernel/config/cluster/$your_cluster_name/idle_timeout_ms > /dev/null; done &
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
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 987da47910 upstream.
Use a straight goto error label style in nfsd_setattr to make sure
we always do the put_write_access call after we got it earlier.
Note that the we have been failing to do that in the case
nfsd_break_lease() returns an error, a bug introduced into 2.6.38 with
6a76bebefe "nfsd4: break lease on nfsd
setattr".
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 818e5a22e9 upstream.
Split out two helpers to make the code more readable and easier to verify
for correctness.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 427d6c6646 upstream.
Someone noticed exportfs happily accepted exports that would later be
rejected when mountd tried to give them to the kernel. Fix this.
This is a regression from 4c1e1b34d5
"nfsd: Store ex_anon_uid and ex_anon_gid as kuids and kgids".
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Reported-by: Yin.JianHong <jiyin@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d49f042aee upstream.
Currently, if the call to nfs_refresh_inode fails, then we end up leaking
a reference count, due to the call to nfs4_get_open_state.
While we're at it, replace nfs4_get_open_state with a simple call to
atomic_inc(); there is no need to do a full lookup of the struct nfs_state
since it is passed as an argument in the struct nfs4_opendata, and
is already assigned to the variable 'state'.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d2bfda2e7a upstream.
Cached opens have already been handled by _nfs4_opendata_reclaim_to_nfs4_state
and can safely skip being reprocessed, but must still call update_open_stateid
to make sure that all active fmodes are recovered.
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a6f951ddbd upstream.
In nfs4_proc_getlk(), when some error causes a retry of the call to
_nfs4_proc_getlk(), we can end up with Oopses of the form
BUG: unable to handle kernel NULL pointer dereference at 0000000000000134
IP: [<ffffffff8165270e>] _raw_spin_lock+0xe/0x30
<snip>
Call Trace:
[<ffffffff812f287d>] _atomic_dec_and_lock+0x4d/0x70
[<ffffffffa053c4f2>] nfs4_put_lock_state+0x32/0xb0 [nfsv4]
[<ffffffffa053c585>] nfs4_fl_release_lock+0x15/0x20 [nfsv4]
[<ffffffffa0522c06>] _nfs4_proc_getlk.isra.40+0x146/0x170 [nfsv4]
[<ffffffffa052ad99>] nfs4_proc_lock+0x399/0x5a0 [nfsv4]
The problem is that we don't clear the request->fl_ops after the first
try and so when we retry, nfs4_set_lock_state() exits early without
setting the lock stateid.
Regression introduced by commit 70cc6487a4
(locks: make ->lock release private data before returning in GETLK case)
Reported-by: Weston Andros Adamson <dros@netapp.com>
Reported-by: Jorge Mora <mora@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d049f74f2d upstream.
The get_dumpable() return value is not boolean. Most users of the
function actually want to be testing for non-SUID_DUMP_USER(1) rather than
SUID_DUMP_DISABLE(0). The SUID_DUMP_ROOT(2) is also considered a
protected state. Almost all places did this correctly, excepting the two
places fixed in this patch.
Wrong logic:
if (dumpable == SUID_DUMP_DISABLE) { /* be protective */ }
or
if (dumpable == 0) { /* be protective */ }
or
if (!dumpable) { /* be protective */ }
Correct logic:
if (dumpable != SUID_DUMP_USER) { /* be protective */ }
or
if (dumpable != 1) { /* be protective */ }
Without this patch, if the system had set the sysctl fs/suid_dumpable=2, a
user was able to ptrace attach to processes that had dropped privileges to
that user. (This may have been partially mitigated if Yama was enabled.)
The macros have been moved into the file that declares get/set_dumpable(),
which means things like the ia64 code can see them too.
CVE-2013-2929
Reported-by: Vasily Kulikov <segoon@openwall.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
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 05e16745c0 upstream.
This issue was first pointed out by Jiaxing Wang several months ago, but no
further comments:
https://lkml.org/lkml/2013/6/29/41
As we know pread() does not change f_pos, so after pread(), file->f_pos
and m->read_pos become different. And seq_lseek() does not update file->f_pos
if offset equals to m->read_pos, so after pread() and seq_lseek()(lseek to
m->read_pos), then a subsequent read may read from a wrong position, the
following program produces the problem:
char str1[32] = { 0 };
char str2[32] = { 0 };
int poffset = 10;
int count = 20;
/*open any seq file*/
int fd = open("/proc/modules", O_RDONLY);
pread(fd, str1, count, poffset);
printf("pread:%s\n", str1);
/*seek to where m->read_pos is*/
lseek(fd, poffset+count, SEEK_SET);
/*supposed to read from poffset+count, but this read from position 0*/
read(fd, str2, count);
printf("read:%s\n", str2);
out put:
pread:
ck_netbios_ns 12665
read:
nf_conntrack_netbios
/proc/modules:
nf_conntrack_netbios_ns 12665 0 - Live 0xffffffffa038b000
nf_conntrack_broadcast 12589 1 nf_conntrack_netbios_ns, Live 0xffffffffa0386000
So we always update file->f_pos to offset in seq_lseek() to fix this issue.
Signed-off-by: Jiaxing Wang <hello.wjx@gmail.com>
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jonghwan Choi <jhbird.choi@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 118b230225 upstream.
dynamic_dname() is both too much and too little for those - the
output may be well in excess of 64 bytes dynamic_dname() assumes
to be enough (thanks to ashmem feeding really long names to
shmem_file_setup()) and vsnprintf() is an overkill for those
guys.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Colin Cross <ccross@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6e4ea8e33b upstream.
If we take the 2nd retry path in ext4_expand_extra_isize_ea, we
potentionally return from the function without having freed these
allocations. If we don't do the return, we over-write the previous
allocation pointers, so we leak either way.
Spotted with Coverity.
[ Fixed by tytso to set is and bs to NULL after freeing these
pointers, in case in the retry loop we later end up triggering an
error causing a jump to cleanup, at which point we could have a double
free bug. -- Ted ]
Signed-off-by: Dave Jones <davej@fedoraproject.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4871c1588f upstream.
btrfs_rename was using the root of the old dir instead of the root of the new
dir when checking for a hash collision, so if you tried to move a file into a
subvol it would freak out because it would see the file you are trying to move
in its current root. This fixes the bug where this would fail
btrfs subvol create test1
btrfs subvol create test2
mv test1 test2.
Thanks to Chris Murphy for catching this,
Reported-by: Chris Murphy <lists@colorremedies.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9d05746e7b upstream.
Olga reported that file descriptors opened with O_PATH do not work with
fstatfs(), found during further development of ksh93's thread support.
There is no reason to not allow O_PATH file descriptors here (fstatfs is
very much a path operation), so use "fdget_raw()". See commit
55815f7014 ("vfs: make O_PATH file descriptors usable for 'fstat()'")
for a very similar issue reported for fstat() by the same team.
Reported-and-tested-by: ольга крыжановская <olga.kryzhanovska@gmail.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b8d0c69b94 upstream.
A user was reporting weird warnings from btrfs_put_delayed_ref() and I noticed
that we were doing this list_del_init() on our head ref outside of
delayed_refs->lock. This is a problem if we have people still on the list, we
could end up modifying old pointers and such. Fix this by removing us from the
list before we do our run_delayed_ref on our head ref. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a05254143c upstream.
We have logic to see if we've already created a parent directory by check to see
if an inode inside of that directory has a lower inode number than the one we
are currently processing. The logic is that if there is a lower inode number
then we would have had to made sure the directory was created at that previous
point. The problem is that subvols inode numbers count from the lowest objectid
in the root tree, which may be less than our current progress. So just skip if
our dir item key is a root item. This fixes the original test and the xfstest
version I made that added an extra subvol create. Thanks,
Reported-by: Emil Karlson <jekarlson@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b6c60c8018 upstream.
Previously we only added blocks to the list to have their backrefs checked if
the level of the block is right above the one we are searching for. This is
because we want to make sure we don't add the entire path up to the root to the
lists to make sure we process things one at a time. This assumes that if any
blocks in the path to the root are going to be not checked (shared in other
words) then they will be in the level right above the current block on up. This
isn't quite right though since we can have blocks higher up the list that are
shared because they are attached to a reloc root. But we won't add this block
to be checked and then later on we will BUG_ON(!upper->checked). So instead
keep track of wether or not we've queued a block to be checked in this current
search, and if we haven't go ahead and queue it to be checked. This patch fixed
the panic I was seeing where we BUG_ON(!upper->checked). Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 997def25e4 upstream.
Commit f5ea1100 cleans up the disk to host conversions for
node directory entries, but because a variable is reused in
xfs_node_toosmall() the next node is not correctly found.
If the original node is small enough (<= 3/8 of the node size),
this change may incorrectly cause a node collapse when it should
not. That will cause an assert in xfstest generic/319:
Assertion failed: first <= last && last < BBTOB(bp->b_length),
file: /root/newest/xfs/fs/xfs/xfs_trans_buf.c, line: 569
Keep the original node header to get the correct forward node.
(When a node is considered for a merge with a sibling, it overwrites the
sibling pointers of the original incore nodehdr with the sibling's
pointers. This leads to loop considering the original node as a merge
candidate with itself in the second pass, and so it incorrectly
determines a merge should occur.)
[v3: added Dave Chinner's (slightly modified) suggestion to the commit header,
cleaned up whitespace. -bpm]
Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7f42ec3941 upstream.
Many NILFS2 users were reported about strange file system corruption
(for example):
NILFS: bad btree node (blocknr=185027): level = 0, flags = 0x0, nchildren = 768
NILFS error (device sda4): nilfs_bmap_last_key: broken bmap (inode number=11540)
But such error messages are consequence of file system's issue that takes
place more earlier. Fortunately, Jerome Poulin <jeromepoulin@gmail.com>
and Anton Eliasson <devel@antoneliasson.se> were reported about another
issue not so recently. These reports describe the issue with segctor
thread's crash:
BUG: unable to handle kernel paging request at 0000000000004c83
IP: nilfs_end_page_io+0x12/0xd0 [nilfs2]
Call Trace:
nilfs_segctor_do_construct+0xf25/0x1b20 [nilfs2]
nilfs_segctor_construct+0x17b/0x290 [nilfs2]
nilfs_segctor_thread+0x122/0x3b0 [nilfs2]
kthread+0xc0/0xd0
ret_from_fork+0x7c/0xb0
These two issues have one reason. This reason can raise third issue
too. Third issue results in hanging of segctor thread with eating of
100% CPU.
REPRODUCING PATH:
One of the possible way or the issue reproducing was described by
Jermoe me Poulin <jeromepoulin@gmail.com>:
1. init S to get to single user mode.
2. sysrq+E to make sure only my shell is running
3. start network-manager to get my wifi connection up
4. login as root and launch "screen"
5. cd /boot/log/nilfs which is a ext3 mount point and can log when NILFS dies.
6. lscp | xz -9e > lscp.txt.xz
7. mount my snapshot using mount -o cp=3360839,ro /dev/vgUbuntu/root /mnt/nilfs
8. start a screen to dump /proc/kmsg to text file since rsyslog is killed
9. start a screen and launch strace -f -o find-cat.log -t find
/mnt/nilfs -type f -exec cat {} > /dev/null \;
10. start a screen and launch strace -f -o apt-get.log -t apt-get update
11. launch the last command again as it did not crash the first time
12. apt-get crashes
13. ps aux > ps-aux-crashed.log
13. sysrq+W
14. sysrq+E wait for everything to terminate
15. sysrq+SUSB
Simplified way of the issue reproducing is starting kernel compilation
task and "apt-get update" in parallel.
REPRODUCIBILITY:
The issue is reproduced not stable [60% - 80%]. It is very important to
have proper environment for the issue reproducing. The critical
conditions for successful reproducing:
(1) It should have big modified file by mmap() way.
(2) This file should have the count of dirty blocks are greater that
several segments in size (for example, two or three) from time to time
during processing.
(3) It should be intensive background activity of files modification
in another thread.
INVESTIGATION:
First of all, it is possible to see that the reason of crash is not valid
page address:
NILFS [nilfs_segctor_complete_write]:2100 bh->b_count 0, bh->b_blocknr 13895680, bh->b_size 13897727, bh->b_page 0000000000001a82
NILFS [nilfs_segctor_complete_write]:2101 segbuf->sb_segnum 6783
Moreover, value of b_page (0x1a82) is 6786. This value looks like segment
number. And b_blocknr with b_size values look like block numbers. So,
buffer_head's pointer points on not proper address value.
Detailed investigation of the issue is discovered such picture:
[-----------------------------SEGMENT 6783-------------------------------]
NILFS [nilfs_segctor_do_construct]:2310 nilfs_segctor_begin_construction
NILFS [nilfs_segctor_do_construct]:2321 nilfs_segctor_collect
NILFS [nilfs_segctor_do_construct]:2336 nilfs_segctor_assign
NILFS [nilfs_segctor_do_construct]:2367 nilfs_segctor_update_segusage
NILFS [nilfs_segctor_do_construct]:2371 nilfs_segctor_prepare_write
NILFS [nilfs_segctor_do_construct]:2376 nilfs_add_checksums_on_logs
NILFS [nilfs_segctor_do_construct]:2381 nilfs_segctor_write
NILFS [nilfs_segbuf_submit_bio]:464 bio->bi_sector 111149024, segbuf->sb_segnum 6783
[-----------------------------SEGMENT 6784-------------------------------]
NILFS [nilfs_segctor_do_construct]:2310 nilfs_segctor_begin_construction
NILFS [nilfs_segctor_do_construct]:2321 nilfs_segctor_collect
NILFS [nilfs_lookup_dirty_data_buffers]:782 bh->b_count 1, bh->b_page ffffea000709b000, page->index 0, i_ino 1033103, i_size 25165824
NILFS [nilfs_lookup_dirty_data_buffers]:783 bh->b_assoc_buffers.next ffff8802174a6798, bh->b_assoc_buffers.prev ffff880221cffee8
NILFS [nilfs_segctor_do_construct]:2336 nilfs_segctor_assign
NILFS [nilfs_segctor_do_construct]:2367 nilfs_segctor_update_segusage
NILFS [nilfs_segctor_do_construct]:2371 nilfs_segctor_prepare_write
NILFS [nilfs_segctor_do_construct]:2376 nilfs_add_checksums_on_logs
NILFS [nilfs_segctor_do_construct]:2381 nilfs_segctor_write
NILFS [nilfs_segbuf_submit_bh]:575 bh->b_count 1, bh->b_page ffffea000709b000, page->index 0, i_ino 1033103, i_size 25165824
NILFS [nilfs_segbuf_submit_bh]:576 segbuf->sb_segnum 6784
NILFS [nilfs_segbuf_submit_bh]:577 bh->b_assoc_buffers.next ffff880218a0d5f8, bh->b_assoc_buffers.prev ffff880218bcdf50
NILFS [nilfs_segbuf_submit_bio]:464 bio->bi_sector 111150080, segbuf->sb_segnum 6784, segbuf->sb_nbio 0
[----------] ditto
NILFS [nilfs_segbuf_submit_bio]:464 bio->bi_sector 111164416, segbuf->sb_segnum 6784, segbuf->sb_nbio 15
[-----------------------------SEGMENT 6785-------------------------------]
NILFS [nilfs_segctor_do_construct]:2310 nilfs_segctor_begin_construction
NILFS [nilfs_segctor_do_construct]:2321 nilfs_segctor_collect
NILFS [nilfs_lookup_dirty_data_buffers]:782 bh->b_count 2, bh->b_page ffffea000709b000, page->index 0, i_ino 1033103, i_size 25165824
NILFS [nilfs_lookup_dirty_data_buffers]:783 bh->b_assoc_buffers.next ffff880219277e80, bh->b_assoc_buffers.prev ffff880221cffc88
NILFS [nilfs_segctor_do_construct]:2367 nilfs_segctor_update_segusage
NILFS [nilfs_segctor_do_construct]:2371 nilfs_segctor_prepare_write
NILFS [nilfs_segctor_do_construct]:2376 nilfs_add_checksums_on_logs
NILFS [nilfs_segctor_do_construct]:2381 nilfs_segctor_write
NILFS [nilfs_segbuf_submit_bh]:575 bh->b_count 2, bh->b_page ffffea000709b000, page->index 0, i_ino 1033103, i_size 25165824
NILFS [nilfs_segbuf_submit_bh]:576 segbuf->sb_segnum 6785
NILFS [nilfs_segbuf_submit_bh]:577 bh->b_assoc_buffers.next ffff880218a0d5f8, bh->b_assoc_buffers.prev ffff880222cc7ee8
NILFS [nilfs_segbuf_submit_bio]:464 bio->bi_sector 111165440, segbuf->sb_segnum 6785, segbuf->sb_nbio 0
[----------] ditto
NILFS [nilfs_segbuf_submit_bio]:464 bio->bi_sector 111177728, segbuf->sb_segnum 6785, segbuf->sb_nbio 12
NILFS [nilfs_segctor_do_construct]:2399 nilfs_segctor_wait
NILFS [nilfs_segbuf_wait]:676 segbuf->sb_segnum 6783
NILFS [nilfs_segbuf_wait]:676 segbuf->sb_segnum 6784
NILFS [nilfs_segbuf_wait]:676 segbuf->sb_segnum 6785
NILFS [nilfs_segctor_complete_write]:2100 bh->b_count 0, bh->b_blocknr 13895680, bh->b_size 13897727, bh->b_page 0000000000001a82
BUG: unable to handle kernel paging request at 0000000000001a82
IP: [<ffffffffa024d0f2>] nilfs_end_page_io+0x12/0xd0 [nilfs2]
Usually, for every segment we collect dirty files in list. Then, dirty
blocks are gathered for every dirty file, prepared for write and
submitted by means of nilfs_segbuf_submit_bh() call. Finally, it takes
place complete write phase after calling nilfs_end_bio_write() on the
block layer. Buffers/pages are marked as not dirty on final phase and
processed files removed from the list of dirty files.
It is possible to see that we had three prepare_write and submit_bio
phases before segbuf_wait and complete_write phase. Moreover, segments
compete between each other for dirty blocks because on every iteration
of segments processing dirty buffer_heads are added in several lists of
payload_buffers:
[SEGMENT 6784]: bh->b_assoc_buffers.next ffff880218a0d5f8, bh->b_assoc_buffers.prev ffff880218bcdf50
[SEGMENT 6785]: bh->b_assoc_buffers.next ffff880218a0d5f8, bh->b_assoc_buffers.prev ffff880222cc7ee8
The next pointer is the same but prev pointer has changed. It means
that buffer_head has next pointer from one list but prev pointer from
another. Such modification can be made several times. And, finally, it
can be resulted in various issues: (1) segctor hanging, (2) segctor
crashing, (3) file system metadata corruption.
FIX:
This patch adds:
(1) setting of BH_Async_Write flag in nilfs_segctor_prepare_write()
for every proccessed dirty block;
(2) checking of BH_Async_Write flag in
nilfs_lookup_dirty_data_buffers() and
nilfs_lookup_dirty_node_buffers();
(3) clearing of BH_Async_Write flag in nilfs_segctor_complete_write(),
nilfs_abort_logs(), nilfs_forget_buffer(), nilfs_clear_dirty_page().
Reported-by: Jerome Poulin <jeromepoulin@gmail.com>
Reported-by: Anton Eliasson <devel@antoneliasson.se>
Cc: Paul Fertser <fercerpav@gmail.com>
Cc: ARAI Shun-ichi <hermes@ceres.dti.ne.jp>
Cc: Piotr Szymaniak <szarpaj@grubelek.pl>
Cc: Juan Barry Manuel Canham <Linux@riotingpacifist.net>
Cc: Zahid Chowdhury <zahid.chowdhury@starsolutions.com>
Cc: Elmer Zhang <freeboy6716@gmail.com>
Cc: Kenneth Langga <klangga@gmail.com>
Signed-off-by: Vyacheslav Dubeyko <slava@dubeyko.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
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 0ab08f576b upstream.
A former patch introducing FUSE_I_SIZE_UNSTABLE flag provided detailed
description of races between ftruncate and anyone who can extend i_size:
> 1. As in the previous scenario fuse_dentry_revalidate() discovered that i_size
> changed (due to our own fuse_do_setattr()) and is going to call
> truncate_pagecache() for some 'new_size' it believes valid right now. But by
> the time that particular truncate_pagecache() is called ...
> 2. fuse_do_setattr() returns (either having called truncate_pagecache() or
> not -- it doesn't matter).
> 3. The file is extended either by write(2) or ftruncate(2) or fallocate(2).
> 4. mmap-ed write makes a page in the extended region dirty.
This patch adds necessary bits to fuse_file_fallocate() to protect from that
race.
Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bde52788bd upstream.
The patch fixes a race between mmap-ed write and fallocate(PUNCH_HOLE):
1) An user makes a page dirty via mmap-ed write.
2) The user performs fallocate(2) with mode == PUNCH_HOLE|KEEP_SIZE
and <offset, size> covering the page.
3) Before truncate_pagecache_range call from fuse_file_fallocate,
the page goes to write-back. The page is fully processed by fuse_writepage
(including end_page_writeback on the page), but fuse_flush_writepages did
nothing because fi->writectr < 0.
4) truncate_pagecache_range is called and fuse_file_fallocate is finishing
by calling fuse_release_nowrite. The latter triggers processing queued
write-back request which will write stale data to the hole soon.
Changed in v2 (thanks to Brian for suggestion):
- Do not truncate page cache until FUSE_FALLOCATE succeeded. Otherwise,
we can end up in returning -ENOTSUPP while user data is already punched
from page cache. Use filemap_write_and_wait_range() instead.
Changed in v3 (thanks to Miklos for suggestion):
- fuse_wait_on_writeback() is prone to livelocks; use fuse_set_nowrite()
instead. So far as we need a dirty-page barrier only, fuse_sync_writes()
should be enough.
- rebased to for-linus branch of fuse.git
Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7202365696 upstream.
A high setting of max_map_count, and a process core-dumping with a large
enough vm_map_count could result in an NT_FILE note not being written,
and the kernel crashing immediately later because it has assumed
otherwise.
Reproduction of the oops-causing bug described here:
https://lkml.org/lkml/2013/8/30/50
Rge ussue originated in commit 2aa362c49c ("coredump: extend core dump
note section to contain file names of mapped file") from Oct 4, 2012.
This patch make that section optional in that case. fill_files_note()
should signify the error, and also let the info struct in
elf_core_dump() be zero-initialized so that we can check for the
optionally written note.
[akpm@linux-foundation.org: avoid abusing E2BIG, remove a couple of not-really-needed local variables]
[akpm@linux-foundation.org: fix sparse warning]
Signed-off-by: Dan Aloni <alonid@stratoscale.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Reported-by: Martin MOKREJS <mmokrejs@gmail.com>
Tested-by: Martin MOKREJS <mmokrejs@gmail.com>
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 4947555584 upstream.
Superblock lock was replaced with (un)lock_super() removal, but left
uninitialized for Seventh Edition UNIX filesystem in the following commit (3.7):
c07cb01 sysv: drop lock/unlock super
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e729eac6f6 upstream.
Refuse RW mount of udf filesystem. So far we just silently changed it
to RO mount but when the media is writeable, block layer won't notice
this change and thus will think device is used RW and will block eject
button of the drive. That is unexpected by users because for
non-writeable media eject button works just fine.
Userspace mount(8) command handles this just fine and retries mounting
with MS_RDONLY set so userspace shouldn't see any regression. Plus any
tool mounting udf is likely confronted with the case of read-only
media where block layer already refuses to mount the filesystem without
MS_RDONLY set so our behavior shouldn't be anything new for it.
Reported-by: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d759bfa4e7 upstream.
Change all function used in filesystem discovery during mount to user
standard kernel return values - -errno on error, 0 on success instead
of 1 on failure and 0 on success. This allows us to pass error number
(not just failure / success) so we can abort device scanning earlier
in case of errors like EIO or ENOMEM . Also we will be able to return
EROFS in case writeable mount is requested but writing isn't supported.
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit efeb9e60d4 upstream.
Userspace can add names containing a slash character to the directory
listing. Don't allow this as it could cause all sorts of trouble.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 06a7c3c278 upstream.
The way how fuse calls truncate_pagecache() from fuse_change_attributes()
is completely wrong. Because, w/o i_mutex held, we never sure whether
'oldsize' and 'attr->size' are valid by the time of execution of
truncate_pagecache(inode, oldsize, attr->size). In fact, as soon as we
released fc->lock in the middle of fuse_change_attributes(), we completely
loose control of actions which may happen with given inode until we reach
truncate_pagecache. The list of potentially dangerous actions includes
mmap-ed reads and writes, ftruncate(2) and write(2) extending file size.
The typical outcome of doing truncate_pagecache() with outdated arguments
is data corruption from user point of view. This is (in some sense)
acceptable in cases when the issue is triggered by a change of the file on
the server (i.e. externally wrt fuse operation), but it is absolutely
intolerable in scenarios when a single fuse client modifies a file without
any external intervention. A real life case I discovered by fsx-linux
looked like this:
1. Shrinking ftruncate(2) comes to fuse_do_setattr(). The latter sends
FUSE_SETATTR to the server synchronously, but before getting fc->lock ...
2. fuse_dentry_revalidate() is asynchronously called. It sends FUSE_LOOKUP
to the server synchronously, then calls fuse_change_attributes(). The
latter updates i_size, releases fc->lock, but before comparing oldsize vs
attr->size..
3. fuse_do_setattr() from the first step proceeds by acquiring fc->lock and
updating attributes and i_size, but now oldsize is equal to
outarg.attr.size because i_size has just been updated (step 2). Hence,
fuse_do_setattr() returns w/o calling truncate_pagecache().
4. As soon as ftruncate(2) completes, the user extends file size by
write(2) making a hole in the middle of file, then reads data from the hole
either by read(2) or mmap-ed read. The user expects to get zero data from
the hole, but gets stale data because truncate_pagecache() is not executed
yet.
The scenario above illustrates one side of the problem: not truncating the
page cache even though we should. Another side corresponds to truncating
page cache too late, when the state of inode changed significantly.
Theoretically, the following is possible:
1. As in the previous scenario fuse_dentry_revalidate() discovered that
i_size changed (due to our own fuse_do_setattr()) and is going to call
truncate_pagecache() for some 'new_size' it believes valid right now. But
by the time that particular truncate_pagecache() is called ...
2. fuse_do_setattr() returns (either having called truncate_pagecache() or
not -- it doesn't matter).
3. The file is extended either by write(2) or ftruncate(2) or fallocate(2).
4. mmap-ed write makes a page in the extended region dirty.
The result will be the lost of data user wrote on the fourth step.
The patch is a hotfix resolving the issue in a simplistic way: let's skip
dangerous i_size update and truncate_pagecache if an operation changing
file size is in progress. This simplistic approach looks correct for the
cases w/o external changes. And to handle them properly, more sophisticated
and intrusive techniques (e.g. NFS-like one) would be required. I'd like to
postpone it until the issue is well discussed on the mailing list(s).
Changed in v2:
- improved patch description to cover both sides of the issue.
Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d331a415ae upstream.
Calls like setxattr and removexattr result in updation of ctime.
Therefore invalidate inode attributes to force a refresh.
Signed-off-by: Anand Avati <avati@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4a4ac4eba1 upstream.
The patch fixes a race between ftruncate(2), mmap-ed write and write(2):
1) An user makes a page dirty via mmap-ed write.
2) The user performs shrinking truncate(2) intended to purge the page.
3) Before fuse_do_setattr calls truncate_pagecache, the page goes to
writeback. fuse_writepage_locked fills FUSE_WRITE request and releases
the original page by end_page_writeback.
4) fuse_do_setattr() completes and successfully returns. Since now, i_mutex
is free.
5) Ordinary write(2) extends i_size back to cover the page. Note that
fuse_send_write_pages do wait for fuse writeback, but for another
page->index.
6) fuse_writepage_locked proceeds by queueing FUSE_WRITE request.
fuse_send_writepage is supposed to crop inarg->size of the request,
but it doesn't because i_size has already been extended back.
Moving end_page_writeback to the end of fuse_writepage_locked fixes the
race because now the fact that truncate_pagecache is successfully returned
infers that fuse_writepage_locked has already called end_page_writeback.
And this, in turn, infers that fuse_flush_writepages has already called
fuse_send_writepage, and the latter used valid (shrunk) i_size. write(2)
could not extend it because of i_mutex held by ftruncate(2).
Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 17b7f7cf58 upstream.
Refuse RW mount of isofs filesystem. So far we just silently changed it
to RO mount but when the media is writeable, block layer won't notice
this change and thus will think device is used RW and will block eject
button of the drive. That is unexpected by users because for
non-writeable media eject button works just fine.
Userspace mount(8) command handles this just fine and retries mounting
with MS_RDONLY set so userspace shouldn't see any regression. Plus any
tool mounting isofs is likely confronted with the case of read-only
media where block layer already refuses to mount the filesystem without
MS_RDONLY set so our behavior shouldn't be anything new for it.
Reported-by: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit aee1c13dd0 upstream.
Don't allow mounting the proc filesystem unless the caller has
CAP_SYS_ADMIN rights over the pid namespace. The principle here is if
you create or have capabilities over it you can mount it, otherwise
you get to live with what other people have mounted.
Andy pointed out that this is needed to prevent users in a user
namespace from remounting proc and specifying different hidepid and gid
options on already existing proc mounts.
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 28e8be3180 upstream.
Call fiemap ioctl(2) with given start offset as well as an desired mapping
range should show extents if possible. However, we somehow figure out the
end offset of mapping via 'mapping_end -= cpos' before iterating the
extent records which would cause problems if the given fiemap length is
too small to a cluster size, e.g,
Cluster size 4096:
debugfs.ocfs2 1.6.3
Block Size Bits: 12 Cluster Size Bits: 12
The extended fiemap test utility From David:
https://gist.github.com/anonymous/6172331
# dd if=/dev/urandom of=/ocfs2/test_file bs=1M count=1000
# ./fiemap /ocfs2/test_file 4096 10
start: 4096, length: 10
File /ocfs2/test_file has 0 extents:
# Logical Physical Length Flags
^^^^^ <-- No extent is shown
In this case, at ocfs2_fiemap(): cpos == mapping_end == 1. Hence the
loop of searching extent records was not executed at all.
This patch remove the in question 'mapping_end -= cpos', and loops
until the cpos is larger than the mapping_end as usual.
# ./fiemap /ocfs2/test_file 4096 10
start: 4096, length: 10
File /ocfs2/test_file has 1 extents:
# Logical Physical Length Flags
0: 0000000000000000 0000000056a01000 0000000006a00000 0000
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reported-by: David Weber <wb@munzinger.de>
Tested-by: David Weber <wb@munzinger.de>
Cc: Sunil Mushran <sunil.mushran@gmail.com>
Cc: Mark Fashen <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.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 bbb651e469 upstream.
If you start the replace procedure on a read only filesystem, at
the end the procedure fails to write the updated dev_items to the
chunk tree. The problem is that this error is not indicated except
for a WARN_ON(). If the user now thinks that everything was done
as expected and destroys the source device (with mkfs or with a
hammer). The next mount fails with "failed to read chunk root" and
the filesystem is gone.
This commit adds code to fail the attempt to start the replace
procedure if the filesystem is mounted read-only.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5208386c50 upstream.
Merge conditions in ext4_setattr() handling inode size changes, also
move ext4_begin_ordered_truncate() call somewhat earlier because it
simplifies error recovery in case of failure. Also add error handling in
case i_disksize update fails.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 933d4b3657 upstream.
If a server sends a lease break to a connection that doesn't have
opens with a lease key specified in the server response, we can't
find an open file to send an ack. Fix this by walking through
all connections we have.
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1a05096de8 upstream.
This happens when we receive a lease break from a server, then
find an appropriate lease key in opened files and schedule the
oplock_break slow work. lw pointer isn't freed in this case.
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 44512449c0 upstream.
NFSv4 reserves readdir cookie values 0-2 for special entries (. and ..),
but jfs allows a value of 2 for a non-special entry. This incompatibility
can result in the nfs client reporting a readdir loop.
This patch doesn't change the value stored internally, but adds one to
the value exposed to the iterate method.
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
[bwh: Backported to 3.2:
- Adjust context
- s/ctx->pos/filp->f_pos/]
Tested-by: Christian Kujau <lists@nerdbynature.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 35dc248383 upstream.
There is a nasty bug in the SCSI SG_IO ioctl that in some circumstances
leads to one process writing data into the address space of some other
random unrelated process if the ioctl is interrupted by a signal.
What happens is the following:
- A process issues an SG_IO ioctl with direction DXFER_FROM_DEV (ie the
underlying SCSI command will transfer data from the SCSI device to
the buffer provided in the ioctl)
- Before the command finishes, a signal is sent to the process waiting
in the ioctl. This will end up waking up the sg_ioctl() code:
result = wait_event_interruptible(sfp->read_wait,
(srp_done(sfp, srp) || sdp->detached));
but neither srp_done() nor sdp->detached is true, so we end up just
setting srp->orphan and returning to userspace:
srp->orphan = 1;
write_unlock_irq(&sfp->rq_list_lock);
return result; /* -ERESTARTSYS because signal hit process */
At this point the original process is done with the ioctl and
blithely goes ahead handling the signal, reissuing the ioctl, etc.
- Eventually, the SCSI command issued by the first ioctl finishes and
ends up in sg_rq_end_io(). At the end of that function, we run through:
write_lock_irqsave(&sfp->rq_list_lock, iflags);
if (unlikely(srp->orphan)) {
if (sfp->keep_orphan)
srp->sg_io_owned = 0;
else
done = 0;
}
srp->done = done;
write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
if (likely(done)) {
/* Now wake up any sg_read() that is waiting for this
* packet.
*/
wake_up_interruptible(&sfp->read_wait);
kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
kref_put(&sfp->f_ref, sg_remove_sfp);
} else {
INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
schedule_work(&srp->ew.work);
}
Since srp->orphan *is* set, we set done to 0 (assuming the
userspace app has not set keep_orphan via an SG_SET_KEEP_ORPHAN
ioctl), and therefore we end up scheduling sg_rq_end_io_usercontext()
to run in a workqueue.
- In workqueue context we go through sg_rq_end_io_usercontext() ->
sg_finish_rem_req() -> blk_rq_unmap_user() -> ... ->
bio_uncopy_user() -> __bio_copy_iov() -> copy_to_user().
The key point here is that we are doing copy_to_user() on a
workqueue -- that is, we're on a kernel thread with current->mm
equal to whatever random previous user process was scheduled before
this kernel thread. So we end up copying whatever data the SCSI
command returned to the virtual address of the buffer passed into
the original ioctl, but it's quite likely we do this copying into a
different address space!
As suggested by James Bottomley <James.Bottomley@hansenpartnership.com>,
add a check for current->mm (which is NULL if we're on a kernel thread
without a real userspace address space) in bio_uncopy_user(), and skip
the copy if we're on a kernel thread.
There's no reason that I can think of for any caller of bio_uncopy_user()
to want to do copying on a kernel thread with a random active userspace
address space.
Huge thanks to Costa Sapuntzakis <costa@purestorage.com> for the
original pointer to this bug in the sg code.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Tested-by: David Milburn <dmilburn@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4bf93b50fd upstream.
Fix the issue with improper counting number of flying bio requests for
BIO_EOPNOTSUPP error detection case.
The sb_nbio must be incremented exactly the same number of times as
complete() function was called (or will be called) because
nilfs_segbuf_wait() will call wail_for_completion() for the number of
times set to sb_nbio:
do {
wait_for_completion(&segbuf->sb_bio_event);
} while (--segbuf->sb_nbio > 0);
Two functions complete() and wait_for_completion() must be called the
same number of times for the same sb_bio_event. Otherwise,
wait_for_completion() will hang or leak.
Signed-off-by: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
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 52e220d357 upstream.
This should actually be returning an ERR_PTR on error instead of NULL.
That was how it was designed and all the callers expect it.
[AV: actually, that's what "VFS: Make clone_mnt()/copy_tree()/collect_mounts()
return errors" missed - originally collect_mounts() was expected to return
NULL on failure]
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
