linux/fs
Roman Pen 2a9b8cba62 ext4: Include forgotten start block on fallocate insert range
While doing 'insert range' start block should be also shifted right.
The bug can be easily reproduced by the following test:

    ptr = malloc(4096);
    assert(ptr);

    fd = open("./ext4.file", O_CREAT | O_TRUNC | O_RDWR, 0600);
    assert(fd >= 0);

    rc = fallocate(fd, 0, 0, 8192);
    assert(rc == 0);
    for (i = 0; i < 2048; i++)
            *((unsigned short *)ptr + i) = 0xbeef;
    rc = pwrite(fd, ptr, 4096, 0);
    assert(rc == 4096);
    rc = pwrite(fd, ptr, 4096, 4096);
    assert(rc == 4096);

    for (block = 2; block < 1000; block++) {
            rc = fallocate(fd, FALLOC_FL_INSERT_RANGE, 4096, 4096);
            assert(rc == 0);

            for (i = 0; i < 2048; i++)
                    *((unsigned short *)ptr + i) = block;

            rc = pwrite(fd, ptr, 4096, 4096);
            assert(rc == 4096);
    }

Because start block is not included in the range the hole appears at
the wrong offset (just after the desired offset) and the following
pwrite() overwrites already existent block, keeping hole untouched.

Simple way to verify wrong behaviour is to check zeroed blocks after
the test:

   $ hexdump ./ext4.file | grep '0000 0000'

The root cause of the bug is a wrong range (start, stop], where start
should be inclusive, i.e. [start, stop].

This patch fixes the problem by including start into the range.  But
not to break left shift (range collapse) stop points to the beginning
of the a block, not to the end.

The other not obvious change is an iterator check on validness in a
main loop.  Because iterator is unsigned the following corner case
should be considered with care: insert a block at 0 offset, when stop
variables overflows and never becomes less than start, which is 0.
To handle this special case iterator is set to NULL to indicate that
end of the loop is reached.

Fixes: 331573febb
Signed-off-by: Roman Pen <roman.penyaev@profitbricks.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: stable@vger.kernel.org
2017-01-08 20:59:35 -05:00
..
9p Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
adfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
affs vfs: remove ".readlink = generic_readlink" assignments 2016-12-09 16:45:04 +01:00
afs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
autofs4 Merge uncontroversial parts of branch 'readlink' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2016-12-17 19:16:12 -08:00
befs befs: add NFS export support 2016-12-22 11:25:24 +00:00
bfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
btrfs Merge uncontroversial parts of branch 'readlink' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2016-12-17 19:16:12 -08:00
cachefiles Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
ceph Merge uncontroversial parts of branch 'readlink' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2016-12-17 19:16:12 -08:00
cifs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
coda vfs: remove ".readlink = generic_readlink" assignments 2016-12-09 16:45:04 +01:00
configfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
cramfs
crypto fscrypt: make fscrypt_operations.key_prefix a string 2017-01-08 01:03:41 -05:00
debugfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
devpts Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
dlm ktime: Get rid of ktime_equal() 2016-12-25 17:21:23 +01:00
ecryptfs vfs: remove ".readlink = generic_readlink" assignments 2016-12-09 16:45:04 +01:00
efivarfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
efs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
exofs exofs: don't mess with simple_write_{begin,end} 2016-12-10 14:25:19 -05:00
exportfs exportfs: be careful to only return expected errors. 2016-10-06 09:07:44 -04:00
ext2 ext2: Return BH_New buffers for zeroed blocks 2016-12-26 20:29:24 -08:00
ext4 ext4: Include forgotten start block on fallocate insert range 2017-01-08 20:59:35 -05:00
f2fs fscrypt: make fscrypt_operations.key_prefix a string 2017-01-08 01:03:41 -05:00
fat Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
freevxfs
fscache
fuse Merge uncontroversial parts of branch 'readlink' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2016-12-17 19:16:12 -08:00
gfs2 ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
hfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
hfsplus Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
hostfs vfs: remove ".readlink = generic_readlink" assignments 2016-12-09 16:45:04 +01:00
hpfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
hugetlbfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
isofs Merge branch 'for-4.10/block' of git://git.kernel.dk/linux-block 2016-12-13 10:19:16 -08:00
jbd2 Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
jffs2 vfs: remove ".readlink = generic_readlink" assignments 2016-12-09 16:45:04 +01:00
jfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
kernfs Merge uncontroversial parts of branch 'readlink' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2016-12-17 19:16:12 -08:00
lockd netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
minix vfs: remove ".readlink = generic_readlink" assignments 2016-12-09 16:45:04 +01:00
ncpfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
nfs ktime: Get rid of ktime_equal() 2016-12-25 17:21:23 +01:00
nfs_common netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
nfsd Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
nilfs2 Merge uncontroversial parts of branch 'readlink' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2016-12-17 19:16:12 -08:00
nls
notify Merge branch 'stable-4.10' of git://git.infradead.org/users/pcmoore/audit 2017-01-05 23:06:06 -08:00
ntfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
ocfs2 ktime: Get rid of the union 2016-12-25 17:21:22 +01:00
omfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
openpromfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
orangefs Merge uncontroversial parts of branch 'readlink' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2016-12-17 19:16:12 -08:00
overlayfs Merge uncontroversial parts of branch 'readlink' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2016-12-17 19:16:12 -08:00
proc Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
pstore Improvements and fixes to pstore subsystem: 2016-12-13 09:16:11 -08:00
qnx4
qnx6
quota Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 2016-12-19 08:23:53 -08:00
ramfs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
reiserfs Merge uncontroversial parts of branch 'readlink' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2016-12-17 19:16:12 -08:00
romfs
squashfs Merge uncontroversial parts of branch 'readlink' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2016-12-17 19:16:12 -08:00
sysfs Merge branch 'for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2016-10-14 12:18:50 -07:00
sysv vfs: remove ".readlink = generic_readlink" assignments 2016-12-09 16:45:04 +01:00
tracefs
ubifs fscrypt: make fscrypt_operations.key_prefix a string 2017-01-08 01:03:41 -05:00
udf block,fs: untangle fs.h and blk_types.h 2016-11-01 09:43:26 -06:00
ufs Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
xfs xfs: fix max_retries _show and _store functions 2017-01-03 20:34:17 -08:00
aio.c ktime: Get rid of the union 2016-12-25 17:21:22 +01:00
anon_inodes.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
attr.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
bad_inode.c bad_inode: add missing i_op initializers 2016-12-09 11:57:43 +01:00
binfmt_aout.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
binfmt_elf_fdpic.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
binfmt_elf.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
binfmt_em86.c
binfmt_flat.c
binfmt_misc.c
binfmt_script.c
block_dev.c Merge branch 'for-linus' of git://git.kernel.dk/linux-block 2017-01-04 09:03:37 -08:00
buffer.c clean_bdev_aliases: Prevent cleaning blocks that are not in block range 2017-01-02 09:35:14 -07:00
char_dev.c
compat_binfmt_elf.c
compat_ioctl.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
compat.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
coredump.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
dax.c dax: Call ->iomap_begin without entry lock during dax fault 2016-12-26 20:29:25 -08:00
dcache.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
dcookies.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
direct-io.c xfs: updates for 4.10-rc1 2016-12-14 21:35:31 -08:00
drop_caches.c
eventfd.c
eventpoll.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
exec.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
fcntl.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
fhandle.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
file_table.c constify alloc_file() 2016-12-05 19:01:16 -05:00
file.c
filesystems.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
fs_pin.c
fs_struct.c
fs-writeback.c fs/fs-writeback.c: remove redundant if check 2016-12-12 18:55:08 -08:00
inode.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
internal.h Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-12-17 18:44:00 -08:00
ioctl.c vfs: call vfs_clone_file_range() under freeze protection 2016-12-16 11:02:54 +01:00
iomap.c xfs: updates for 4.10-rc1 2016-12-14 21:35:31 -08:00
Kconfig Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-12-16 10:24:44 -08:00
Kconfig.binfmt docs: fix locations of several documents that got moved 2016-10-24 08:12:35 -02:00
libfs.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
locks.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
Makefile logfs: remove from tree 2016-12-14 23:48:11 -05:00
mbcache.c mbcache: document that "find" functions only return reusable entries 2016-12-03 15:55:01 -05:00
mount.h vfs: add path_is_mountpoint() helper 2016-12-03 20:51:35 -05:00
mpage.c fs: Add helper to clean bdev aliases under a bh and use it 2016-11-04 14:34:47 -06:00
namei.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
namespace.c Merge branch 'work.namespace' into for-linus 2016-12-22 23:04:31 -05:00
no-block.c
nsfs.c net: add an ioctl to get a socket network namespace 2016-10-31 10:56:36 -04:00
open.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
pipe.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
pnode.c reorganize do_make_slave() 2016-12-16 16:30:49 -05:00
pnode.h
posix_acl.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-10 20:16:43 -07:00
proc_namespace.c
read_write.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
readdir.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
select.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
seq_file.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
signalfd.c
splice.c splice: reinstate SIGPIPE/EPIPE handling 2016-12-21 10:59:34 -08:00
stack.c
stat.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
statfs.c vfs: misc struct path constification 2016-12-05 19:03:49 -05:00
super.c quota: Remove dqonoff_mutex 2016-11-30 08:38:07 +01:00
sync.c
timerfd.c ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
userfaultfd.c mm: join struct fault_env and vm_fault 2016-12-14 16:04:09 -08:00
utimes.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
xattr.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00