linux/fs
Jan Kara c725bfce79 vfs: Make sendfile(2) killable even better
Commit 296291cdd1 (mm: make sendfile(2) killable) fixed an issue where
sendfile(2) was doing a lot of tiny writes into a filesystem and thus
was unkillable for a long time. However sendfile(2) can be (mis)used to
issue lots of writes into arbitrary file descriptor such as evenfd or
similar special file descriptors which never hit the standard filesystem
write path and thus are still unkillable. E.g. the following example
from Dmitry burns CPU for ~16s on my test system without possibility to
be killed:

        int r1 = eventfd(0, 0);
        int r2 = memfd_create("", 0);
        unsigned long n = 1<<30;
        fallocate(r2, 0, 0, n);
        sendfile(r1, r2, 0, n);

There are actually quite a few tests for pending signals in sendfile
code however we data to write is always available none of them seems to
trigger. So fix the problem by adding a test for pending signal into
splice_from_pipe_next() also before the loop waiting for pipe buffers to
be available. This should fix all the lockup issues with sendfile of the
do-ton-of-tiny-writes nature.

CC: stable@vger.kernel.org
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-11-23 21:15:30 -05:00
..
9p 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
adfs fs/adfs: remove unneeded cast 2015-06-30 19:44:57 -07:00
affs fs/affs: make root lookup from blkdev logical size 2015-09-10 13:29:01 -07:00
afs net: Add a struct net parameter to sock_create_kern 2015-05-11 10:50:17 -04:00
autofs4 make simple_positive() public 2015-06-23 18:02:01 -04:00
befs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-07-04 19:36:06 -07:00
bfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
btrfs Merge branch 'for-linus-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2015-11-13 16:30:29 -08:00
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 Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6 2015-11-13 16:40:36 -08:00
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: fix refcount imbalance in start_creating 2015-11-11 02:04:44 -05:00
devpts devpts: if initialization failed, don't crash when opening /dev/ptmx 2015-06-30 19:44:58 -07:00
dlm Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2015-11-13 20:04:17 -08:00
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 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-05-06 10:57:37 -07:00
efs fs/efs: femove unneeded cast 2015-06-25 17:00:42 -07:00
exofs fs/exofs/namei.c: remove unnecessary new_valid_dev() check 2015-11-09 15:11:24 -08:00
exportfs
ext2 ext2, ext4: warn when mounting with dax enabled 2015-11-16 09:43:54 -08:00
ext4 ext2, ext4: warn when mounting with dax enabled 2015-11-16 09:43:54 -08:00
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 freevxfs: Grammar s/an negative/a negative/ 2015-08-07 13:59:24 +02:00
fscache FS-Cache: Handle a write to the page immediately beyond the EOF marker 2015-11-11 02:11:02 -05:00
fuse Move locks API users to locks_lock_inode_wait() 2015-10-22 14:57:36 -04:00
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 fs: create and use seq_show_option for escaping 2015-09-04 16:54:41 -07:00
hpfs fs/hpfs/namei.c: remove unnecessary new_valid_dev() check 2015-11-09 15:11:24 -08:00
hugetlbfs mm/hugetlbfs: fix bugs in fallocate hole punch of areas with holes 2015-11-20 16:17:32 -08:00
isofs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
jbd2 Merge branch 'akpm' (patches from Andrew) 2015-11-07 14:32:45 -08:00
jffs2 xattr handlers: Pass handler to operations instead of flags 2015-11-13 20:34:32 -05:00
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 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-07-04 19:36:06 -07:00
ncpfs ncpfs: don't allow negative timeouts 2015-11-20 16:17:32 -08:00
nfs 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
nfs_common lockd: NLM grace period shouldn't block NFSv4 opens 2015-08-13 10:22:06 -04:00
nfsd nfsd: fix race with open / open upgrade stateids 2015-11-10 09:29:45 -05:00
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 umask ignored issue 2015-11-20 16:17:32 -08:00
omfs omfs: fix potential integer overflow in allocator 2015-05-28 18:25:19 -07:00
openpromfs
overlayfs Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2015-10-31 14:49:19 -07:00
proc Merge branch 'akpm' (patches from Andrew) 2015-11-07 14:32:45 -08:00
pstore pstore: fix code comment to match code 2015-11-02 13:41:52 -08:00
qnx4
qnx6 pagemap.h: move dir_pages() over there 2015-06-23 18:02:00 -04:00
quota Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-09-05 20:34:28 -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: Don't modify filesystem for read-only mounts 2015-08-20 14:58:35 +02:00
ufs fix ufs write vs readpage race when writing into a hole 2015-09-09 10:43:12 -07:00
xfs 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
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_fdpic.c libnvdimm for 4.4: 2015-11-10 12:07:22 -08:00
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_em86.c
binfmt_flat.c
binfmt_misc.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
binfmt_script.c
block_dev.c block: protect rw_page against device teardown 2015-11-19 13:47:10 -08:00
buffer.c vfs: remove unused wrapper block_page_mkwrite() 2015-11-11 02:19:33 -05:00
char_dev.c fs/char_dev.c: fix incorrect documentation for unregister_chrdev_region 2015-08-05 13:49:35 -07:00
compat_binfmt_elf.c
compat_ioctl.c i2c-dev: Fix typo in ioctl name reference 2015-10-23 23:26:43 +02:00
compat.c
coredump.c coredump: change zap_threads() and zap_process() to use for_each_thread() 2015-11-06 17:50:42 -08:00
dax.c dax: disable pmd mappings 2015-11-16 23:54:45 -08:00
dcache.c dcache: Reduce the scope of i_lock in d_splice_alias 2015-08-21 02:34:37 -04:00
dcookies.c
direct-io.c Merge branch 'for-4.4/io-poll' of git://git.kernel.dk/linux-block 2015-11-10 17:23:49 -08:00
drop_caches.c inode: convert inode_sb_list_lock to per-sb 2015-08-17 18:39:46 -04:00
eventfd.c
eventpoll.c
exec.c vfs: Commit to never having exectuables on proc and sysfs. 2015-07-10 10:39:25 -05:00
fcntl.c
fhandle.c vfs: read file_handle only once in handle_to_path 2015-06-02 10:29:07 -07:00
file_table.c fs, file table: reinit files_stat.max_files after deferred memory initialisation 2015-08-07 04:39:40 +03:00
file.c vfs: clear remainder of 'full_fds_bits' in dup_fd() 2015-11-05 23:05:32 -08:00
filesystems.c
fs_pin.c
fs_struct.c
fs-writeback.c fs: fix writeback.c kernel-doc warnings 2015-11-11 02:18:27 -05:00
inode.c fs: fix inode.c kernel-doc warning 2015-11-11 02:18:27 -05:00
internal.h inode: rename i_wb_list to i_io_list 2015-08-17 23:38:10 -04:00
ioctl.c
Kconfig dax: disable pmd mappings 2015-11-16 23:54:45 -08:00
Kconfig.binfmt mm: split ET_DYN ASLR from mmap ASLR 2015-04-14 16:49:05 -07:00
libfs.c fs: Set the size of empty dirs to 0. 2015-08-12 15:28:45 -05:00
locks.c locks: cleanup posix_lock_inode_wait and flock_lock_inode_wait 2015-10-22 14:57:42 -04:00
Makefile ext4: promote ext4 over ext2 in the default probe order 2015-10-15 10:33:21 -04:00
mbcache.c
mount.h fs: use seq_open_private() for proc_mounts 2015-06-30 19:44:56 -07:00
mpage.c mm, fs: introduce mapping_gfp_constraint() 2015-11-06 17:50:42 -08:00
namei.c Merge branch 'akpm' (patches from Andrew) 2015-11-07 14:32:45 -08:00
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: Commit to never having exectuables on proc and sysfs. 2015-07-10 10:39:25 -05:00
pipe.c fs/pipe.c: return error code rather than 0 in pipe_write() 2015-11-11 02:18:26 -05:00
pnode.c
pnode.h mnt: Clarify and correct the disconnect logic in umount_tree 2015-07-22 20:33:27 -05:00
posix_acl.c xattr handlers: Pass handler to operations instead of flags 2015-11-13 20:34:32 -05:00
proc_namespace.c fs: use seq_open_private() for proc_mounts 2015-06-30 19:44:56 -07:00
read_write.c
readdir.c
select.c locking/arch: Rename set_mb() to smp_store_mb() 2015-05-19 08:32:00 +02:00
seq_file.c fs, seqfile: always allow oom killer 2015-11-06 17:50:42 -08:00
signalfd.c signalfd: fix information leak in signalfd_copyinfo 2015-08-07 04:39:40 +03:00
splice.c vfs: Make sendfile(2) killable even better 2015-11-23 21:15:30 -05:00
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 Merge branch 'superblock-scaling' of git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-next into for-next 2015-08-21 02:31:20 -04:00
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
userfaultfd.c userfaultfd: revert "userfaultfd: waitqueue: add nr wake parameter to __wake_up_locked_key" 2015-09-22 15:09:53 -07:00
utimes.c
xattr.c 9p: xattr simplifications 2015-11-13 20:34:33 -05:00