Willy Tarreau fa6d0ba12a pipe: limit the per-user amount of pages allocated in pipes ... commit 759c01142a5d0f364a462346168a56de28a80f52 upstream. On no-so-small systems, it is possible for a single process to cause an OOM condition by filling large pipes with data that are never read. A typical process filling 4000 pipes with 1 MB of data will use 4 GB of memory. On small systems it may be tricky to set the pipe max size to prevent this from happening. This patch makes it possible to enforce a per-user soft limit above which new pipes will be limited to a single page, effectively limiting them to 4 kB each, as well as a hard limit above which no new pipes may be created for this user. This has the effect of protecting the system against memory abuse without hurting other users, and still allowing pipes to work correctly though with less data at once. The limit are controlled by two new sysctls : pipe-user-pages-soft, and pipe-user-pages-hard. Both may be disabled by setting them to zero. The default soft limit allows the default number of FDs per process (1024) to create pipes of the default size (64kB), thus reaching a limit of 64MB before starting to create only smaller pipes. With 256 processes limited to 1024 FDs each, this results in 1024*64kB + (256*1024 - 1024) * 4kB = 1084 MB of memory allocated for a user. The hard limit is disabled by default to avoid breaking existing applications that make intensive use of pipes (eg: for splicing). Reported-by: socketpair@gmail.com Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Mitigates: CVE-2013-4312 (Linux 2.0+) Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Moritz Muehlenhoff <moritz@wikimedia.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2016-06-07 18:14:35 -07:00
..
9p	9p: ->evict_inode() should kick out ->i_data, not ->i_mapping	2015-12-08 14:51:16 -05:00
adfs
affs	affs: fix remount failure when there are no options changed	2016-06-07 18:14:32 -07:00
afs
autofs4
befs
bfs
btrfs	Btrfs: don't use src fd for printk	2016-06-01 12:15:47 -07:00
cachefiles	FS-Cache: Add missing initialization of ret in cachefiles_write_page()	2015-11-16 20:38:43 -05:00
ceph	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client	2015-11-13 09:24:40 -08:00
cifs	fs/cifs: correctly to anonymous authentication for the NTLM(v2) authentication	2016-06-01 12:15:48 -07:00
coda	fs/coda: fix readlink buffer overflow	2015-09-10 13:29:01 -07:00
configfs	configfs: allow dynamic group creation	2015-11-20 16:17:32 -08:00
cramfs
debugfs	debugfs: Make automount point inodes permanently empty	2016-05-04 14:48:41 -07:00
devpts	pty: make sure super_block is still valid in final /dev/tty close	2016-02-25 12:01:14 -08:00
dlm	net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA	2015-12-01 15:45:05 -05:00
ecryptfs	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2015-11-07 13:05:44 -08:00
efivarfs	efi: Make efivarfs entries immutable by default	2016-03-03 15:07:09 -08:00
efs
exofs	osd fs: __r4w_get_page rely on PageUptodate for uptodate	2015-12-12 10:15:34 -08:00
exportfs
ext2	ext2, ext4: warn when mounting with dax enabled	2015-11-16 09:43:54 -08:00
ext4	ext4: iterate over buffer heads correctly in move_extent_per_page()	2016-06-01 12:15:48 -07:00
f2fs	Merge branch 'for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2015-11-13 18:02:30 -08:00
fat	fat: fix fake_offset handling on error path	2015-11-20 16:17:32 -08:00
freevxfs
fscache	FS-Cache: Handle a write to the page immediately beyond the EOF marker	2015-11-11 02:11:02 -05:00
fuse	fuse: Add reference counting for fuse_io_priv	2016-04-12 09:08:58 -07:00
gfs2	Merge branch 'for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2015-11-13 18:02:30 -08:00
hfs	hfs: fix B-tree corruption after insertion at position 0	2015-09-10 13:29:01 -07:00
hfsplus	xattr handlers: Pass handler to operations instead of flags	2015-11-13 20:34:32 -05:00
hostfs	uml: fix hostfs mknod()	2016-03-03 15:07:12 -08:00
hpfs	hpfs: implement the show_options method	2016-06-01 12:15:54 -07:00
hugetlbfs	fs/hugetlbfs/inode.c: fix bugs in hugetlb_vmtruncate_list()	2016-02-25 12:01:22 -08:00
isofs	get_rock_ridge_filename(): handle malformed NM entries	2016-05-18 17:06:54 -07:00
jbd2	jbd2: fix FS corruption possibility in jbd2_journal_destroy() on umount path	2016-04-12 09:08:53 -07:00
jffs2	jffs2: reduce the breakage on recovery from halfway failed rename()	2016-03-16 08:42:58 -07:00
jfs	fs/jfs: remove unnecessary new_valid_dev() checks	2015-11-09 15:11:24 -08:00
kernfs	kernfs: implement kernfs_path_len()	2015-08-18 15:49:15 -07:00
lockd	Mainly smaller bugfixes and cleanup. We're still finding some bugs from	2015-11-11 20:11:28 -08:00
logfs	mm, fs: introduce mapping_gfp_constraint()	2015-11-06 17:50:42 -08:00
minix
ncpfs	ncpfs: fix a braino in OOM handling in ncp_fill_cache()	2016-03-16 08:42:59 -07:00
nfs	nfs: use file_dentry()	2016-04-20 15:42:13 +09:00
nfs_common
nfsd	nfsd: fix deadlock secinfo+readdir compound	2016-04-12 09:09:03 -07:00
nilfs2	Merge branch 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2015-11-11 09:45:24 -08:00
nls
notify	inotify: actually check for invalid bits in sys_inotify_add_watch()	2015-11-05 19:34:48 -08:00
ntfs	mm, fs: introduce mapping_gfp_constraint()	2015-11-06 17:50:42 -08:00
ocfs2	ocfs2: fix posix_acl_create deadlock	2016-05-18 17:06:44 -07:00
omfs
openpromfs
overlayfs	fs: add file_dentry()	2016-04-20 15:42:12 +09:00
proc	proc: prevent accessing /proc/<PID>/environ until it's ready	2016-05-11 11:21:16 +02:00
pstore	pstore: fix code comment to match code	2015-11-02 13:41:52 -08:00
qnx4
qnx6
quota	quota: Fix possible GPF due to uninitialised pointers	2016-04-12 09:08:56 -07:00
ramfs	mm, fs: obey gfp_mapping for add_to_page_cache()	2015-10-16 11:42:28 -07:00
reiserfs	Merge branch 'for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2015-11-13 18:02:30 -08:00
romfs
squashfs	squashfs: xattr simplifications	2015-11-13 20:34:33 -05:00
sysfs	platform/chrome: Branch for v4.4	2015-11-13 21:53:18 -08:00
sysv	fix sysvfs symlinks	2015-11-23 21:11:08 -05:00
tracefs	tracefs: Fix refcount imbalance in start_creating()	2015-11-04 22:13:45 -05:00
ubifs	Merge branch 'for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2015-11-13 18:02:30 -08:00
udf	udf: Check output buffer length when converting name to CS0	2016-02-25 12:01:18 -08:00
ufs	fix ufs write vs readpage race when writing into a hole	2015-09-09 10:43:12 -07:00
xfs	xfs: fix two memory leaks in xfs_attr_list.c error paths	2016-04-12 09:08:56 -07:00
aio.c	mm: move ->mremap() from file_operations to vm_operations_struct	2015-09-04 16:54:41 -07:00
anon_inodes.c
attr.c
bad_inode.c
binfmt_aout.c
binfmt_elf.c	Merge branch 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2015-11-11 09:45:24 -08:00
binfmt_elf_fdpic.c	libnvdimm for 4.4:	2015-11-10 12:07:22 -08:00
binfmt_em86.c
binfmt_flat.c
binfmt_misc.c
binfmt_script.c
block_dev.c	block: detach bdev inode from its wb in __blkdev_put()	2015-12-04 11:02:17 -07:00
buffer.c	vfs: remove unused wrapper block_page_mkwrite()	2015-11-11 02:19:33 -05:00
char_dev.c
compat.c
compat_binfmt_elf.c
compat_ioctl.c	i2c-dev: Fix typo in ioctl name reference	2015-10-23 23:26:43 +02:00
coredump.c	fs/coredump: prevent fsuid=0 dumps into user-controlled directories	2016-04-12 09:08:58 -07:00
dax.c	dax: disable pmd mappings	2015-11-16 23:54:45 -08:00
dcache.c	fs: add file_dentry()	2016-04-20 15:42:12 +09:00
dcookies.c
direct-io.c	block: fix use-after-free in dio_bio_complete	2016-03-03 15:07:28 -08:00
drop_caches.c
eventfd.c
eventpoll.c
exec.c
fcntl.c
fhandle.c	fs/coredump: prevent fsuid=0 dumps into user-controlled directories	2016-04-12 09:08:58 -07:00
file.c	vfs: clear remainder of 'full_fds_bits' in dup_fd()	2015-11-05 23:05:32 -08:00
file_table.c
filesystems.c
fs-writeback.c	writeback, cgroup: fix use of the wrong bdi_writeback which mismatches the inode	2016-04-12 09:09:04 -07:00
fs_pin.c
fs_struct.c
inode.c	fs: fix inode.c kernel-doc warning	2015-11-11 02:18:27 -05:00
internal.h
ioctl.c
Kconfig	dax: disable pmd mappings	2015-11-16 23:54:45 -08:00
Kconfig.binfmt
libfs.c
locks.c	locks: fix unlock when fcntl_setlk races with a close	2016-03-03 15:07:12 -08:00
Makefile	ext4: promote ext4 over ext2 in the default probe order	2015-10-15 10:33:21 -04:00
mbcache.c
mount.h
mpage.c	mm, fs: introduce mapping_gfp_constraint()	2015-11-06 17:50:42 -08:00
namei.c	atomic_open(): fix the handling of create_error	2016-05-18 17:06:51 -07:00
namespace.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2015-09-01 16:13:25 -07:00
no-block.c
nsfs.c	fs/seq_file: convert int seq_vprint/seq_printf/etc... returns to void	2015-09-11 15:21:34 -07:00
open.c	vfs: add vfs_select_inode() helper	2016-05-18 17:06:48 -07:00
pipe.c	pipe: limit the per-user amount of pages allocated in pipes	2016-06-07 18:14:35 -07:00
pnode.c	propogate_mnt: Handle the first propogated copy being a slave	2016-05-11 11:21:19 +02:00
pnode.h
posix_acl.c	xattr handlers: Pass handler to operations instead of flags	2015-11-13 20:34:32 -05:00
proc_namespace.c	vfs: show_vfsstat: do not ignore errors from show_devname method	2016-04-12 09:08:55 -07:00
read_write.c
readdir.c
select.c
seq_file.c	fs, seqfile: always allow oom killer	2015-11-06 17:50:42 -08:00
signalfd.c
splice.c	splice: handle zero nr_pages in splice_to_pipe()	2016-04-12 09:08:55 -07:00
stack.c
stat.c	fs/stat.c: remove unnecessary new_valid_dev() check	2015-11-09 15:11:24 -08:00
statfs.c
super.c	writeback: flush inode cgroup wb switches instead of pinning super_block	2016-03-09 15:34:52 -08:00
sync.c	fs/sync.c: make sync_file_range(2) use WB_SYNC_NONE writeback	2015-11-06 17:50:42 -08:00
timerfd.c	timerfd: Handle relative timers with CONFIG_TIME_LOW_RES proper	2016-02-25 12:01:25 -08:00
userfaultfd.c	userfaultfd: don't block on the last VM updates at exit time	2016-03-16 08:43:01 -07:00
utimes.c
xattr.c	9p: xattr simplifications	2015-11-13 20:34:33 -05:00