This bug was found with smatch (http://repo.or.cz/w/smatch.git/). If
we return directly the inode->i_mutex lock doesn't get released.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
Lockdep gripes if file->f_lock is taken in a no-IRQ situation, since that
is not always the case. We don't really want to disable IRQs for every
acquisition of f_lock; instead, just move it outside of fasync_lock.
Reported-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Reported-by: Larry Finger <Larry.Finger@lwfinger.net>
Reported-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
check_unsafe_exec() also notes whether the fs_struct is being
shared by more threads than will get killed by the exec, and if so
sets LSM_UNSAFE_SHARE to make bprm_set_creds() careful about euid.
But /proc/<pid>/cwd and /proc/<pid>/root lookups make transient
use of get_fs_struct(), which also raises that sharing count.
This might occasionally cause a setuid program not to change euid,
in the same way as happened with files->count (check_unsafe_exec
also looks at sighand->count, but /proc doesn't raise that one).
We'd prefer exec not to unshare fs_struct: so fix this in procfs,
replacing get_fs_struct() by get_fs_path(), which does path_get
while still holding task_lock, instead of raising fs->count.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: stable@kernel.org
___
fs/proc/base.c | 50 +++++++++++++++--------------------------------
1 file changed, 16 insertions(+), 34 deletions(-)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Malicki reports that setuid sometimes doesn't: very rarely,
a setuid root program does not get root euid; and, by the way,
they have a health check running lsof every few minutes.
Right, check_unsafe_exec() notes whether the files_struct is being
shared by more threads than will get killed by the exec, and if so
sets LSM_UNSAFE_SHARE to make bprm_set_creds() careful about euid.
But /proc/<pid>/fd and /proc/<pid>/fdinfo lookups make transient
use of get_files_struct(), which also raises that sharing count.
There's a rather simple fix for this: exec's check on files->count
has been redundant ever since 2.6.1 made it unshare_files() (except
while compat_do_execve() omitted to do so) - just remove that check.
[Note to -stable: this patch will not apply before 2.6.29: earlier
releases should just remove the files->count line from unsafe_exec().]
Reported-by: Joe Malicki <jmalicki@metacarta.com>
Narrowed-down-by: Michael Itz <mitz@metacarta.com>
Tested-by: Joe Malicki <jmalicki@metacarta.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2.6.26's commit fd8328be87
"sanitize handling of shared descriptor tables in failing execve()"
moved the unshare_files() from flush_old_exec() and several binfmts
to the head of do_execve(); but forgot to make the same change to
compat_do_execve(), leaving a CLONE_FILES files_struct shared across
exec from a 32-bit process on a 64-bit kernel.
It's arguable whether the files_struct really ought to be unshared
across exec; but 2.6.1 made that so to stop the loading binary's fd
leaking into other threads, and a 32-bit process on a 64-bit kernel
ought to behave in the same way as 32 on 32 and 64 on 64.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-quota-2.6: (27 commits)
ext2: Zero our b_size in ext2_quota_read()
trivial: fix typos/grammar errors in fs/Kconfig
quota: Coding style fixes
quota: Remove superfluous inlines
quota: Remove uppercase aliases for quota functions.
nfsd: Use lowercase names of quota functions
jfs: Use lowercase names of quota functions
udf: Use lowercase names of quota functions
ufs: Use lowercase names of quota functions
reiserfs: Use lowercase names of quota functions
ext4: Use lowercase names of quota functions
ext3: Use lowercase names of quota functions
ext2: Use lowercase names of quota functions
ramfs: Remove quota call
vfs: Use lowercase names of quota functions
quota: Remove dqbuf_t and other cleanups
quota: Remove NODQUOT macro
quota: Make global quota locks cacheline aligned
quota: Move quota files into separate directory
ext4: quota reservation for delayed allocation
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm:
dlm: fix length calculation in compat code
dlm: ignore cancel on granted lock
dlm: clear defunct cancel state
dlm: replace idr with hash table for connections
dlm: comment typo fixes
dlm: use ipv6_addr_copy
dlm: Change rwlock which is only used in write mode to a spinlock
To be on the safe side, it should be less fragile to exclude I_NEW inodes
from inode list scans by default (unless there is an important reason to
have them).
Normally they will get excluded (eg. by zero refcount or writecount etc),
however it is a bit fragile for list walkers to know exactly what parts of
the inode state is set up and valid to test when in I_NEW. So along these
lines, move I_NEW checks upward as well (sometimes taking I_FREEING etc
checks with them too -- this shouldn't be a problem should it?)
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
new_pts_mount() (including the get_sb_nodev()), shares a lot of code
with init_pts_mount(). The only difference between them is the 'test-super'
function passed into sget().
Move all common code into devpts_get_sb() and remove the new_pts_mount() and
init_pts_mount() functions,
Changelog[v3]:
[Serge Hallyn]: Remove unnecessary printk()s
Changelog[v2]:
(Christoph Hellwig): Merge code in 'do_pts_mount()' into devpts_get_sb()
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Tested-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
With mknod_ptmx() moved to devpts_get_sb(), init_pts_mount() becomes
a wrapper around get_init_pts_sb(). Remove get_init_pts_sb() and
fold code into init_pts_mount().
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We create 'ptmx' node in both single-instance and multiple-instance
mounts. So devpts_get_sb() can call mknod_ptmx() once rather than
have both modes calling mknod_ptmx() separately.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Since all the mount option parsing is done in devpts, we could do it
just once and pass it around in devpts functions and eventually store
it in the super block.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
On remount, devpts fs only needs to parse the mount options. Users cannot
directly create/dirty files in /dev/pts so the MS_RDONLY flag and
shrinking the dcache does not really apply to devpts.
So effectively on remount, devpts only parses the mount options and updates
these options in its super block. As such, we could replace do_remount_sb()
call with a direct parse_mount_options().
Doing so enables subsequent patches to avoid parsing the mount options twice
and simplify the code.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
simple_set_mnt() is defined as returning 'int' but always returns 0.
Callers assume simple_set_mnt() never fails and don't properly cleanup if
it were to _ever_ fail. For instance, get_sb_single() and get_sb_nodev()
should:
up_write(sb->s_unmount);
deactivate_super(sb);
if simple_set_mnt() fails.
Since simple_set_mnt() never fails, would be cleaner if it did not
return anything.
[akpm@linux-foundation.org: fix build]
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Move some block device related code out from buffer.c and put it in
block_dev.c. I'm trying to move non-buffer_head code out of buffer.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We should drop the ->s_umount mutex if an error occurs after the
sget()/grab_super() call. This was introduced when adding support
for multiple instances of devpts and noticed during a code review/reorg.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The last user of do_pipe is in arch/alpha/, after replacing it with
do_pipe_flags, the do_pipe can be totally dropped.
Signed-off-by: Cheng Renquan <crquan@gmail.com>
Acked-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Copy symlink data into the union member it is accessed through. Although
this shouldn't make a difference to behaviour it makes the code easier
to follow and grep through. It may also prevent problems if the
struct/union definitions change in the future.
Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Ensure fast symlink targets are NUL-terminated, even if corrupted
on-disk.
Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
ufs2 fast symlinks can be twice as long as ufs ones, however the code
was using the ufs size in various places. Fix that so ufs2 symlinks over
60 characters aren't truncated.
Note that we copy the entire area instead of using the maxsymlinklen field
from the superblock. This way we will be more robust against corruption (of
the superblock).
While we are at it, use memcpy instead of open-coding it with for loops.
Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The maximum fast symlink size is set in the superblock of certain types
of UFS filesystem. Before using it we need to check that it isn't longer
than the available space we have in the inode.
Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add a switch for the various i_mode fmt cases, and remove the comment
about writeability of devices nodes - that part is handled in
inode_permission and comment on (briefly) there.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Make sure that comments describe what's going on and not how, and always
use __d_instantiate instead of two separate branches, one with
d_instantiate and one with __d_instantiate.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Due to a different size of ino_t ustat needs a compat handler, but
currently only x86 and mips provide one. Add a generic compat_sys_ustat
and switch all architectures over to it. Instead of doing various
user copy hacks compat_sys_ustat just reimplements sys_ustat as
it's trivial. This was suggested by Arnd Bergmann.
Found by Eric Sandeen when running xfstests/017 on ppc64, which causes
stack smashing warnings on RHEL/Fedora due to the too large amount of
data writen by the syscall.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In two error cases affs_remove_link doesn't call affs_unlock_dir to
release the i_hash_lock semaphore.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'bkl-removal' of git://git.lwn.net/linux-2.6:
Rationalize fasync return values
Move FASYNC bit handling to f_op->fasync()
Use f_lock to protect f_flags
Rename struct file->f_ep_lock
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6: (81 commits)
[S390] remove duplicated #includes
[S390] cpumask: use mm_cpumask() wrapper
[S390] cpumask: Use accessors code.
[S390] cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits.
[S390] cpumask: remove cpu_coregroup_map
[S390] fix clock comparator save area usage
[S390] Add hwcap flag for the etf3 enhancement facility
[S390] Ensure that ipl panic notifier is called late.
[S390] fix dfp elf hwcap/facility bit detection
[S390] smp: perform initial cpu reset before starting a cpu
[S390] smp: fix memory leak on __cpu_up
[S390] ipl: Improve checking logic and remove switch defaults.
[S390] s390dbf: Remove needless check for NULL pointer.
[S390] s390dbf: Remove redundant initilizations.
[S390] use kzfree()
[S390] BUG to BUG_ON changes
[S390] zfcpdump: Prevent zcore from beeing built as a kernel module.
[S390] Use csum_partial in checksum.h
[S390] cleanup lowcore.h
[S390] eliminate ipl_device from lowcore
...
* 'for-2.6.30' of git://git.kernel.dk/linux-2.6-block:
Get rid of pdflush_operation() in emergency sync and remount
btrfs: get rid of current_is_pdflush() in btrfs_btree_balance_dirty
Move the default_backing_dev_info out of readahead.c and into backing-dev.c
block: Repeated lines in switching-sched.txt
bsg: Remove bogus check against request_queue->max_sectors
block: WARN in __blk_put_request() for potential bio leak
loop: fix circular locking in loop_clr_fd()
loop: support barrier writes
bsg: add support for tail queuing
cpqarray: enable bus mastering
block: genhd.h cleanup patch
block: add private bio_set for bio integrity allocations
block: genhd.h comment needs updating
block: get rid of unused blkdev_free_rq() define
block: remove various blk_queue_*() setting functions in blk_init_queue_node()
cciss: add BUILD_BUG_ON() for catching bad CommandList_struct alignment
block: don't create bio_vec slabs of less than the inline number
block: cleanup bio_alloc_bioset()
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1750 commits)
ixgbe: Allow Priority Flow Control settings to survive a device reset
net: core: remove unneeded include in net/core/utils.c.
e1000e: update version number
e1000e: fix close interrupt race
e1000e: fix loss of multicast packets
e1000e: commonize tx cleanup routine to match e1000 & igb
netfilter: fix nf_logger name in ebt_ulog.
netfilter: fix warning in ebt_ulog init function.
netfilter: fix warning about invalid const usage
e1000: fix close race with interrupt
e1000: cleanup clean_tx_irq routine so that it completely cleans ring
e1000: fix tx hang detect logic and address dma mapping issues
bridge: bad error handling when adding invalid ether address
bonding: select current active slave when enslaving device for mode tlb and alb
gianfar: reallocate skb when headroom is not enough for fcb
Bump release date to 25Mar2009 and version to 0.22
r6040: Fix second PHY address
qeth: fix wait_event_timeout handling
qeth: check for completion of a running recovery
qeth: unregister MAC addresses during recovery.
...
Manually fixed up conflicts in:
drivers/infiniband/hw/cxgb3/cxio_hal.h
drivers/infiniband/hw/nes/nes_nic.c
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
[CIFS] Fix memory overwrite when saving nativeFileSystem field during mount
[CIFS] Rename compose_mount_options to cifs_compose_mount_options.
[CIFS] work around bug in Samba server handling for posix open
[CIFS] Use posix open on file open when server supports it
cifs: fix buffer format byte on NT Rename/hardlink
[CIFS] Add definitions for remoteably fsctl calls
[CIFS] add extra null attr check
[CIFS] fix build error
[CIFS] reopen file via newer posix open protocol operation if available
[CIFS] Add new nostrictsync cifs mount option to avoid slow SMB flush
[CIFS] DFS no longer experimental
[CIFS] Send SMB flush in cifs_fsync
We don't have to start a transaction in writepage() when all the blocks
are a properly allocated. Even in ordered mode either the data has been
written via write() and they are thus already added to transaction's list
or the data was written via mmap and then it's random in which transaction
they get written anyway.
This should help VM to pageout dirty memory without blocking on transaction
commits.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw:
GFS2: Fix freeze issue
Fix a minor bug in the previous patch
GFS2: Clean up of glops.c
GFS2: Fix locking bug in failed shared to exclusive conversion
GFS2: Pagecache usage optimization on GFS2
GFS2: fix sparse warning: Should it be static?
GFS2: fix sparse warnings: constant is so big it is ...
GFS2: Support quota/noquota mount arguments
GFS2: Fix alignment issue and tidy gfs2_bitfit
GFS2: Add a "demote a glock" interface to sysfs
GFS2: Expose UUID via sysfs/uevent
GFS2: Support generation of discard requests
GFS2: Fix deadlock on journal flush
GFS2: Fix error path ref counting for root inode
GFS2: Remove unused field from glock
GFS2: Merge lock_dlm module into GFS2
GFS2: Remove "double" locking in quota
GFS2: change gfs2_quota_scan into a shrinker
GFS2: Bring back lvb-related stuff to lock_nolock to support quotas
GFS2: Fix remount argument parsing
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: (71 commits)
SELinux: inode_doinit_with_dentry drop no dentry printk
SELinux: new permission between tty audit and audit socket
SELinux: open perm for sock files
smack: fixes for unlabeled host support
keys: make procfiles per-user-namespace
keys: skip keys from another user namespace
keys: consider user namespace in key_permission
keys: distinguish per-uid keys in different namespaces
integrity: ima iint radix_tree_lookup locking fix
TOMOYO: Do not call tomoyo_realpath_init unless registered.
integrity: ima scatterlist bug fix
smack: fix lots of kernel-doc notation
TOMOYO: Don't create securityfs entries unless registered.
TOMOYO: Fix exception policy read failure.
SELinux: convert the avc cache hash list to an hlist
SELinux: code readability with avc_cache
SELinux: remove unused av.decided field
SELinux: more careful use of avd in avc_has_perm_noaudit
SELinux: remove the unused ae.used
SELinux: check seqno when updating an avc_node
...
Change the default behaviour of the kernel to use relatime for all
filesystems. This can be overridden with the "strictatime" mount
option.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add support for explicitly requesting full atime updates. This makes it
possible for kernels to default to relatime but still allow userspace to
override it.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Allow atime to be updated once per day even with relatime. This lets
utilities like tmpreaper (which delete files based on last access time)
continue working, making relatime a plausible default for distributions.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Valerie Aurora Henson <vaurora@redhat.com>
Acked-by: Alan Cox <alan@redhat.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The dasd device driver will now support ECKD devices with more then
65520 cylinders.
In the traditional ECKD adressing scheme each track is addressed
by a 16-bit cylinder and 16-bit head number. The new addressing
scheme makes use of the fact that the actual number of heads is
never larger then 15, so 12 bits of the head number can be redefined
to be part of the cylinder address.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Opencode a cheasy approach with kevent. The idea here is that we'll
add some generic delayed work infrastructure, which probably wont be
based on pdflush (or maybe it will, in which case we can just add it
back).
This is in preparation for getting rid of pdflush completely.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
ext2_quota_read() doesn't initialize tmp_bh.b_size before calling
ext2_get_block() where we access it. Since it is a local variable it
might contain some garbage. Make sure it is filled with reasonable
value before passing.
Signed-off-by: Manish Katiyar <mkatiyar@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
Use lowercase names of quota functions instead of old uppercase ones.
CC: bfields@fieldses.org
CC: neilb@suse.de
Signed-off-by: Jan Kara <jack@suse.cz>
Use lowercase names of quota functions instead of old uppercase ones.
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Kleikamp <shaggy@austin.ibm.com>
Use lowercase names of quota functions instead of old uppercase ones.
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Mingming Cao <cmm@us.ibm.com>
CC: linux-ext4@vger.kernel.org
Use lowercase names of quota functions instead of old uppercase ones.
Signed-off-by: Jan Kara <jack@suse.cz>
CC: Alexander Viro <viro@zeniv.linux.org.uk>
Remove bogus typedef which is just a definition of char *.
Remove unnecessary type casts.
Substitute freedqbuf() with kfree.
Signed-off-by: Jan Kara <jack@suse.cz>
Andrew Morton has suggested that three global quota locks can end up in the
same cacheline which can result in bad cacheline ping-pong on SMP machines.
Make locks cacheline aligned so that we avoid this problem (thanks goes to
Andrew for the idea).
Signed-off-by: Jan Kara <jack@suse.cz>
CC: Andrew Morton <akpm@linux-foundation.org>
Uses quota reservation/claim/release to handle quota properly for delayed
allocation in the three steps: 1) quotas are reserved when data being copied
to cache when block allocation is defered 2) when new blocks are allocated.
reserved quotas are converted to the real allocated quota, 2) over-booked
quotas for metadata blocks are released back.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
According to checkpatch: EXPORT_SYMBOL(foo); should immediately follow its
function/variable
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Reserved quota will be claimed at the block allocation time. Over-booked
quota could be returned back with the release callback function.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Delayed allocation defers the block allocation at the dirty pages
flush-out time, doing quota charge/check at that time is too late.
But we can't charge the quota blocks until blocks are really allocated,
otherwise users could get overcharged after reboot from system crash.
This patch adds quota reservation for delayed allocation. Quota blocks
are reserved in memory, inode and quota won't gets dirtied until later
block allocation time.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Commit 86c9508eb1c0ce5aa07b5cf1d36b60c54efc3d7a
"sysfs: don't block indefinitely for unmapped files" in linux-next
crashes the PowerMac G5 when X starts up. It's caught out by the way
powerpc's pci_mmap of legacy_mem uses shmem_zero_setup(), substituting
a new vma->vm_file whose private_data no longer points to the bin_buffer
(substitution done because some versions of X crash if that mmap fails).
The fix to this is straightforward: the original vm_file is fput() in
that case, so this mmap won't block sysfs at all, so just don't switch
over to bin_vm_ops if vm_file has changed.
But more fixes made before realizing that was the problem:-
It should not be an error if bin_page_mkwrite() finds no underlying
page_mkwrite().
Check that a file already mmap'ed has the same underlying vm_ops
_before_ pointing vma->vm_ops at bin_vm_ops.
If the file being mmap'ed is a shmem/tmpfs file, don't fail the mmap
on CONFIG_NUMA=y, just because that has a set_policy and get_policy:
provide bin_set_policy, bin_get_policy and bin_migrate.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Acked-by: Eric Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The only way for a sysfs attribute to remove itself (without
deadlock) is to use the sysfs_schedule_callback() interface.
Vegard Nossum discovered that a poorly written sysfs ->store
callback can repeatedly schedule remove callbacks on the same
device over and over, e.g.
$ while true ; do echo 1 > /sys/devices/.../remove ; done
If the 'remove' attribute uses the sysfs_schedule_callback API
and also does not protect itself from concurrent accesses, its
callback handler will be called multiple times, and will
eventually attempt to perform operations on a freed kobject,
leading to many problems.
Instead of requiring all callers of sysfs_schedule_callback to
implement their own synchronization, provide the protection in
the infrastructure.
Now, sysfs_schedule_callback will only allow one scheduled
callback per kobject. On subsequent calls with the same kobject,
return -EAGAIN.
This is a short term fix. The long term fix is to allow sysfs
attributes to remove themselves directly, without any of this
callback hokey pokey.
[cornelia.huck@de.ibm.com: s390 ccwgroup bits]
Reported-by: vegard.nossum@gmail.com
Signed-off-by: Alex Chiang <achiang@hp.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch implements uevent suppress in kobject and removes it
from struct device, based on the following ideas:
1,Uevent sending should be one attribute of kobject, so suppressing it
in kobject layer is more natural than in device layer. By this way,
we can do it for other objects embedded with kobject.
2,It may save several bytes for each instance of struct device.(On my
omap3(32bit ARM) based box, can save 8bytes per device object)
This patch also introduces dev_set|get_uevent_suppress() helpers to
set and query uevent_suppress attribute in case to help kobject
as private part of struct device in future.
[This version is against the latest driver-core patch set of Greg,please
ignore the last version.]
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Modify sysfs bin files so that we can remove the bin file while they are
still mapped. When the kobject is removed we unmap the bin file and
arrange for future accesses to the mapping to receive SIGBUS.
Implementing this prevents a nasty DOS when pci devices are hot plugged
and unplugged. Where if any of their resources were mmaped the kernel
could not free up their pci resources or release their pci data
structures.
[akpm@linux-foundation.org: remove unused var]
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The sysfs_dirent serves as both an inode and a directory entry
for sysfs. To prevent the sysfs inode numbers from being freed
prematurely hold a reference to sysfs_dirent from the sysfs inode.
[akpm@linux-foundation.org: add comment]
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sysfs: sysfs_add_one WARNs with full path to duplicate filename
As a debugging aid, it can be useful to know the full path to a
duplicate file being created in sysfs.
We now will display warnings such as:
sysfs: cannot create duplicate filename '/foo'
when attempting to create multiple files named 'foo' in the sysfs
root, or:
sysfs: cannot create duplicate filename '/bus/pci/slots/5/foo'
when attempting to create multiple files named 'foo' under a
given directory in sysfs.
The path displayed is always a relative path to sysfs_root. The
leading '/' in the path name refers to the sysfs_root mount
point, and should not be confused with the "real" '/'.
Thanks to Alex Williamson for essentially writing sysfs_pathname.
Cc: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sysfs_get_inode ultimately calls sysfs_count_nlink when the a
directory inode is fectched. sysfs_count_nlink needs to be
called under the sysfs_mutex to guard against the unlikely
but possible scenario that the root directory is changing
as we are counting the number entries in it, and just in
general to be consistent.
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
SYSFS_MAGIC has been added into magic.h, so only use that definition
in magic.h to avoid potential consistency problem.
Signed-off-by: Qinghuang Feng <qhfeng.kernel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The integrity bio allocation needs its own bio_set to avoid violating
the mempool allocation rules and risking deadlocks.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
If we don't have CONFIG_BLK_DEV_INTEGRITY set, then we don't have
any external dependencies on the bio_vec slabs. So don't create
the ones that we will inline anyway.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
this warning (which got fixed by commit b2bf968):
fs/bio.c: In function ‘bio_alloc_bioset’:
fs/bio.c:305: warning: ‘p’ may be used uninitialized in this function
Triggered because the code flow in bio_alloc_bioset() is correct
but a bit complex for the compiler to see through.
Streamline it a bit - this also makes the code a tiny bit more compact:
text data bss dec hex filename
7540 256 40 7836 1e9c bio.o.before
7539 256 40 7835 1e9b bio.o.after
Also remove an older compiler-warnings annotation from this function,
it's not needed.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This removes some old code that was causing issues during
filesystem freeze.
Reported-by: Andrew Price <andy@andrewprice.me.uk>
Tested-by: Andrew Price <andy@andrewprice.me.uk>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The logic requires that we mark the glock dirty in page_mkwrite
otherwise we might not flush correctly in the case that no
allocation was required in the process of dirying the page.
Also we need to set the shared write flag early for the same
reason.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This cleans up a number of bits of code mostly based in glops.c.
A couple of simple functions have been merged into the callers
to make it more obvious what is going on, the mysterious raising
of i_writecount around the truncate_inode_pages() call has been
removed. The meta_go_* operations have been renamed rgrp_go_*
since that is the only lock type that they are used with.
The unused argument of gfs2_read_sb has been removed. Also
a bug has been fixed where a check for the rindex inode was
in the wrong callback. More comments are added, and the
debugging code is improved too.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
After calling out to the dlm, GFS2 sets the new state of a glock to
gl_target in gdlm_ast(). However, gl_target is not always the lock
state that was requested. If a conversion from shared to exclusive
fails, finish_xmote() will call do_xmote() with LM_ST_UNLOCKED, instead
of gl->gl_target, so that it can reacquire the lock in exlusive the next
time around. In this case, setting the lock to gl_target in gdlm_ast()
will make GFS2 think that it has the glock in exclusive mode, when
really, it doesn't have the glock locked at all. This patch adds a new
field to the gfs2_glock structure, gl_req, to track the mode that was
requested.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Linus Torvalds