KOSAKI Motohiro 98bc93e505 proc: fix pagemap_read() error case ... Currently, pagemap_read() has three error and/or corner case handling mistake. (1) If ppos parameter is wrong, mm refcount will be leak. (2) If count parameter is 0, mm refcount will be leak too. (3) If the current task is sleeping in kmalloc() and the system is out of memory and oom-killer kill the proc associated task, mm_refcount prevent the task free its memory. then system may hang up. <Quote Hugh's explain why we shold call kmalloc() before get_mm()> check_mem_permission gets a reference to the mm. If we __get_free_page after check_mem_permission, imagine what happens if the system is out of memory, and the mm we're looking at is selected for killing by the OOM killer: while we wait in __get_free_page for more memory, no memory is freed from the selected mm because it cannot reach exit_mmap while we hold that reference. This patch fixes the above three. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jovi Zhang <bookjovi@gmail.com> Acked-by: Hugh Dickins <hughd@google.com> Cc: Stephen Wilson <wilsons@start.ca> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2011-05-26 17:12:37 -07:00
..
9p	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2011-05-26 09:52:14 -07:00
adfs	Fix common misspellings	2011-03-31 11:26:23 -03:00
affs	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
afs	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
autofs4	vfs: push dentry_unhash on rmdir into file systems	2011-05-26 07:26:47 -04:00
befs	Fix common misspellings	2011-03-31 11:26:23 -03:00
bfs	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
btrfs	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem	2011-05-26 10:50:56 -07:00
cachefiles	Fix common misspellings	2011-03-31 11:26:23 -03:00
ceph	ceph: remove unnecessary dentry_unhash calls	2011-05-26 07:26:53 -04:00
cifs	cifs: remove unnecessary dentry_unhash on rmdir/rename_dir	2011-05-26 07:26:59 -04:00
coda	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
configfs	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2011-05-26 09:52:14 -07:00
cramfs	cramfs: generate unique inode number for better inode cache usage	2011-01-13 08:03:23 -08:00
debugfs	debugfs: move to new strtobool	2011-05-19 16:55:28 +09:30
devpts	fs/devpts/inode.c: correctly check d_alloc_name() return code in devpts_pty_new()	2011-03-22 17:44:17 -07:00
dlm	Merge branch 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6	2011-05-26 13:19:00 -07:00
ecryptfs	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
efs	block: remove per-queue plugging	2011-03-10 08:52:07 +01:00
exofs	exofs: remove unnecessary dentry_unhash on rmdir/rename_dir	2011-05-26 07:26:57 -04:00
exportfs	vfs: Add open by file handle support	2011-03-15 02:21:44 -04:00
ext2	ext2: remove unnecessary dentry_unhash on rmdir/rename_dir	2011-05-26 07:26:56 -04:00
ext3	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem	2011-05-26 10:50:56 -07:00
ext4	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem	2011-05-26 10:50:56 -07:00
fat	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2011-05-26 09:52:14 -07:00
freevxfs	treewide: fix a few typos in comments	2011-05-10 10:16:21 +02:00
fscache	fscache: remove dead code under CONFIG_WORKQUEUE_DEBUGFS	2011-05-25 08:39:44 -07:00
fuse	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2011-05-26 09:52:14 -07:00
gfs2	Merge branch 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6	2011-05-26 13:19:00 -07:00
hfs	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
hfsplus	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
hostfs	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
hpfs	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2011-05-26 09:52:14 -07:00
hppfs
hugetlbfs	mm: don't access vm_flags as 'int'	2011-05-26 09:20:31 -07:00
isofs	Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block	2011-03-24 10:16:26 -07:00
jbd	jbd: Fix comment to match the code in journal_start()	2011-05-24 00:27:53 +02:00
jbd2	Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4	2011-05-26 09:53:20 -07:00
jffs2	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
jfs	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
lockd	NLM: Fix "kernel BUG at fs/lockd/host.c:417!" or ".../host.c:283!"	2011-01-25 15:24:47 -05:00
logfs	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2011-05-26 09:52:14 -07:00
minix	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
ncpfs	memcg: add the pagefault count into memcg stats	2011-05-26 17:12:36 -07:00
nfs	nfs: remove unnecessary dentry_unhash on rmdir/rename_dir	2011-05-26 07:26:57 -04:00
nfs_common	Fix common misspellings	2011-03-31 11:26:23 -03:00
nfsd	treewide: fix a few typos in comments	2011-05-10 10:16:21 +02:00
nilfs2	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2011-05-26 09:52:14 -07:00
nls
notify	Merge branch 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6	2011-04-07 11:14:49 -07:00
ntfs	Fix common misspellings	2011-03-31 11:26:23 -03:00
ocfs2	Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2	2011-05-26 10:55:15 -07:00
omfs	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
openpromfs
partitions	Merge branch 'for-2.6.40/core' of git://git.kernel.dk/linux-2.6-block	2011-05-25 09:14:07 -07:00
proc	proc: fix pagemap_read() error case	2011-05-26 17:12:37 -07:00
pstore	pstore: fix pstore filesystem mount/remount issue	2011-05-16 11:05:00 -07:00
qnx4	block: remove per-queue plugging	2011-03-10 08:52:07 +01:00
quota	vmscan: change shrinker API by passing shrink_control struct	2011-05-25 08:39:26 -07:00
ramfs	ramfs: fix memleak on no-mmu arch	2011-04-14 16:06:56 -07:00
reiserfs	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
romfs
squashfs	treewide: fix a few typos in comments	2011-05-10 10:16:21 +02:00
sysfs	sysfs: remove "last sysfs file:" line from the oops messages	2011-05-13 16:05:51 -07:00
sysv	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
ubifs	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2011-05-26 09:52:14 -07:00
udf	vfs: push dentry_unhash on rename_dir into file systems	2011-05-26 07:26:48 -04:00
ufs	ufs: fix truncated values handling 64 bit metadata	2011-05-26 17:12:33 -07:00
xfs	Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs	2011-05-26 10:49:11 -07:00
aio.c	Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block	2011-03-24 10:16:26 -07:00
anon_inodes.c	sanitize vfsmount refcounting changes	2011-01-16 13:47:07 -05:00
attr.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
bad_inode.c
binfmt_aout.c
binfmt_elf.c	brk: COMPAT_BRK: fix detection of randomized brk	2011-04-14 16:06:55 -07:00
binfmt_elf_fdpic.c
binfmt_em86.c
binfmt_flat.c	CRED: Fix load_flat_shared_library() to initialise bprm correctly	2011-05-03 10:10:51 +10:00
binfmt_misc.c
binfmt_script.c
binfmt_som.c
bio-integrity.c	block: Require subsystems to explicitly allocate bio_set integrity mempool	2011-03-17 11:11:05 +01:00
bio.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
block_dev.c	block: move bd_set_size() above rescan_partitions() in __blkdev_get()	2011-05-23 08:50:48 -07:00
buffer.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem	2011-05-26 10:50:56 -07:00
char_dev.c	Merge branch 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block	2011-01-13 10:45:01 -08:00
compat.c	exec: unify do_execve/compat_do_execve code	2011-04-09 15:53:56 +02:00
compat_binfmt_elf.c
compat_ioctl.c
dcache.c	vmscan: change shrinker API by passing shrink_control struct	2011-05-25 08:39:26 -07:00
dcookies.c
direct-io.c	Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block	2011-03-24 10:16:26 -07:00
drop_caches.c	vmscan: change shrinker API by passing shrink_control struct	2011-05-25 08:39:26 -07:00
eventfd.c	Docbook: add fs/eventfd.c and fix typos in it	2011-02-21 15:07:04 -08:00
eventpoll.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
exec.c	coredump: add support for exe_file in core name	2011-05-26 17:12:36 -07:00
fcntl.c	userns: rename is_owner_or_cap to inode_owner_or_capable	2011-03-23 19:47:13 -07:00
fhandle.c	fs/fhandle.c: add <linux/personality.h> for ia64	2011-04-14 16:06:56 -07:00
fifo.c	Filesystem: fifo: Fixed coding style issue.	2011-03-21 00:16:09 -04:00
file.c	vfs: avoid large kmalloc()s for the fdtable	2011-04-28 11:28:20 -07:00
file_table.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2011-03-16 13:26:17 -07:00
filesystems.c	fs: synchronize_rcu when unregister_filesystem success not failure	2011-04-17 10:42:01 -07:00
fs-writeback.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
fs_struct.c	sanitize vfsmount refcounting changes	2011-01-16 13:47:07 -05:00
generic_acl.c	userns: rename is_owner_or_cap to inode_owner_or_capable	2011-03-23 19:47:13 -07:00
inode.c	vmscan: change shrinker API by passing shrink_control struct	2011-05-25 08:39:26 -07:00
internal.h	fs: move i_wb_list out from under inode_lock	2011-03-24 21:17:51 -04:00
ioctl.c	vfs: cleanup do_vfs_ioctl()	2011-03-21 00:16:08 -04:00
ioprio.c
Kconfig	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2011-05-26 09:52:14 -07:00
Kconfig.binfmt
libfs.c	libfs: drop unneeded dentry_unhash	2011-05-26 07:26:50 -04:00
locks.c	Merge branch 'for-2.6.39' of git://linux-nfs.org/~bfields/linux	2011-03-24 08:20:39 -07:00
Makefile	Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6	2011-03-16 19:01:29 -07:00
mbcache.c	vmscan: change shrinker API by passing shrink_control struct	2011-05-25 08:39:26 -07:00
mpage.c	mm/fs: add hooks to support cleancache	2011-05-26 10:01:43 -06:00
namei.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2011-05-26 09:52:14 -07:00
namespace.c	fs/namespace.c: bound mount propagation fix	2011-05-26 07:26:44 -04:00
nfsctl.c	open-style analog of vfs_path_lookup()	2011-03-14 09:15:28 -04:00
no-block.c
open.c	fs: Use BUG_ON(!mnt) at dentry_open().	2011-03-21 01:10:41 -04:00
pipe.c	Fix broken "pipe: use event aware wakeups" optimization	2011-01-20 16:21:59 -08:00
pnode.c
pnode.h
posix_acl.c	NFS: Prevent memory allocation failure in nfsacl_encode()	2011-01-25 15:24:47 -05:00
read_write.c	fix signedness mess in rw_verify_area() on 64bit architectures	2011-01-12 20:06:58 -05:00
read_write.h
readdir.c
select.c	select: remove unused MAX_SELECT_SECONDS	2011-03-21 00:16:08 -04:00
seq_file.c
signalfd.c
splice.c	splice: add wakeup_pipe_readers()	2011-05-23 19:58:53 +02:00
stack.c
stat.c	readlinkat(), fchownat() and fstatat() with empty relative pathnames	2011-03-15 02:21:45 -04:00
statfs.c	clean statfs-like syscalls up	2011-03-14 09:15:28 -04:00
super.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem	2011-05-26 10:50:56 -07:00
sync.c	Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block	2011-03-24 10:16:26 -07:00
timerfd.c	timerfd: Manage cancelable timers in timerfd	2011-05-23 13:59:53 +02:00
utimes.c	userns: rename is_owner_or_cap to inode_owner_or_capable	2011-03-23 19:47:13 -07:00
xattr.c	vfs: Pass setxattr(2) flags properly	2011-04-21 07:34:44 -07:00
xattr_acl.c