linux/fs
Markus Rechberger 4d7bf11d64 ext2/3/4: fix file date underflow on ext2 3 filesystems on 64 bit systems
Taken from http://bugzilla.kernel.org/show_bug.cgi?id=5079

signed long ranges from -2.147.483.648 to 2.147.483.647 on x86 32bit

10000011110110100100111110111101 .. -2,082,844,739
10000011110110100100111110111101 ..  2,212,122,557 <- this currently gets
stored on the disk but when converting it to a 64bit signed long value it loses
its sign and becomes positive.

Cc: Andreas Dilger <adilger@dilger.ca>
Cc: <linux-ext4@vger.kernel.org>

Andreas says:

This patch is now treating timestamps with the high bit set as negative
times (before Jan 1, 1970).  This means we lose 1/2 of the possible range
of timestamps (lopping off 68 years before unix timestamp overflow -
now only 30 years away :-) to handle the extremely rare case of setting
timestamps into the distant past.

If we are only interested in fixing the underflow case, we could just
limit the values to 0 instead of storing negative values.  At worst this
will skew the timestamp by a few hours for timezones in the far east
(files would still show Jan 1, 1970 in "ls -l" output).

That said, it seems 32-bit systems (mine at least) allow files to be set
into the past (01/01/1907 works fine) so it seems this patch is bringing
the x86_64 behaviour into sync with other kernels.

On the plus side, we have a patch that is ready to add nanosecond timestamps
to ext3 and as an added bonus adds 2 high bits to the on-disk timestamp so
this extends the maximum date to 2242.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:14:58 -07:00
..
9p v9fs: don't use primary fid when removing file 2007-04-24 08:23:08 -07:00
adfs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
affs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
afs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
autofs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
autofs4 [PATCH] autofs4: fix race in unhashed dentry code 2007-04-12 15:31:42 -07:00
befs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
bfs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
cifs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
coda slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
configfs remove "struct subsystem" as it is no longer needed 2007-05-02 18:57:59 -07:00
cramfs mm: make read_cache_page synchronous 2007-05-07 12:12:51 -07:00
debugfs remove "struct subsystem" as it is no longer needed 2007-05-02 18:57:59 -07:00
devpts [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
dlm Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw 2007-05-07 12:26:27 -07:00
ecryptfs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
efs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
exportfs
ext2 ext2/3/4: fix file date underflow on ext2 3 filesystems on 64 bit systems 2007-05-08 11:14:58 -07:00
ext3 ext2/3/4: fix file date underflow on ext2 3 filesystems on 64 bit systems 2007-05-08 11:14:58 -07:00
ext4 ext2/3/4: fix file date underflow on ext2 3 filesystems on 64 bit systems 2007-05-08 11:14:58 -07:00
fat slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
freevxfs mm: make read_cache_page synchronous 2007-05-07 12:12:51 -07:00
fuse Merge branch 'server-cluster-locking-api' of git://linux-nfs.org/~bfields/linux 2007-05-07 12:34:24 -07:00
gfs2 Factor outstanding I/O error handling 2007-05-08 11:14:57 -07:00
hfs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
hfsplus slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
hostfs uml: hostfs style fixes 2007-05-08 11:14:57 -07:00
hpfs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
hppfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
hugetlbfs hugetlbfs: add NULL check in hugetlb_zero_setup() 2007-05-07 12:12:57 -07:00
isofs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
jbd [PATCH] jbd: wait for already submitted t_sync_datalist buffer to complete 2006-12-22 08:55:51 -08:00
jbd2 [PATCH] jbd2: wait for already submitted t_sync_datalist buffer to complete 2006-12-07 08:39:42 -08:00
jffs2 slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
jfs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
lockd Merge branch 'server-cluster-locking-api' of git://linux-nfs.org/~bfields/linux 2007-05-07 12:34:24 -07:00
minix slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
msdos [PATCH] mark struct inode_operations const 2 2007-02-12 09:48:46 -08:00
ncpfs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
nfs Merge branch 'server-cluster-locking-api' of git://linux-nfs.org/~bfields/linux 2007-05-07 12:34:24 -07:00
nfs_common
nfsd Merge branch 'server-cluster-locking-api' of git://linux-nfs.org/~bfields/linux 2007-05-07 12:34:24 -07:00
nls [PATCH] fs: make nls_cp936.c handle some U00XY characters and U20AC correctly 2006-12-07 08:39:46 -08:00
ntfs mm: move common segment checks to separate helper function 2007-05-08 11:14:57 -07:00
ocfs2 slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
openpromfs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
partitions mm: optimize acorn partition truncate 2007-05-07 12:12:55 -07:00
proc Allow access to /proc/$PID/fd after setuid() 2007-05-08 11:14:58 -07:00
qnx4 slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
ramfs [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
reiserfs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
romfs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
smbfs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
sysfs remove "struct subsystem" as it is no longer needed 2007-05-02 18:57:59 -07:00
sysv slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
udf slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
ufs slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
vfat [PATCH] mark struct inode_operations const 3 2007-02-12 09:48:46 -08:00
xfs mm: move common segment checks to separate helper function 2007-05-08 11:14:57 -07:00
aio.c KMEM_CACHE(): simplify slab cache creation 2007-05-07 12:12:55 -07:00
attr.c
bad_inode.c [PATCH] mark struct inode_operations const 1 2007-02-12 09:48:46 -08:00
binfmt_aout.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
binfmt_elf_fdpic.c [PATCH] fix page leak during core dump 2007-04-02 10:06:08 -07:00
binfmt_elf.c [PATCH] fix page leak during core dump 2007-04-02 10:06:08 -07:00
binfmt_em86.c
binfmt_flat.c [PATCH] uclinux: correctly remap bin_fmtflat exe allocated mem regions 2007-02-09 10:45:33 -08:00
binfmt_misc.c [PATCH] Mark struct super_operations const 2007-02-12 09:48:47 -08:00
binfmt_script.c
binfmt_som.c
bio.c KMEM_CACHE(): simplify slab cache creation 2007-05-07 12:12:55 -07:00
block_dev.c slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
buffer.c block_write_full_page(): report ENOSPC 2007-05-08 11:14:57 -07:00
char_dev.c [PATCH] remove protection of LANANA-reserved majors 2007-04-04 21:12:47 -07:00
compat_ioctl.c [PATCH] x86-64: Shut up warnings for vfat compat ioctls on other file systems 2007-05-02 19:27:21 +02:00
compat.c [PATCH] x86-64: Print type and size correctly for unknown compat ioctls 2007-05-02 19:27:21 +02:00
dcache.c KMEM_CACHE(): simplify slab cache creation 2007-05-07 12:12:55 -07:00
dcookies.c [PATCH] slab: remove kmem_cache_t 2006-12-07 08:39:25 -08:00
direct-io.c [PATCH] dio: lock refcount operations 2006-12-10 09:57:21 -08:00
dnotify.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
dquot.c mm: remove destroy_dirty_buffers from invalidate_bdev() 2007-05-07 12:12:55 -07:00
drop_caches.c [PATCH] remove invalidate_inode_pages() 2007-02-11 10:51:31 -08:00
eventpoll.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
exec.c exec.c: fix coredump to pipe problem and obscure "security hole" 2007-04-17 16:36:26 -07:00
fcntl.c [PATCH] fdtable: Make fdarray and fdsets equal in size 2006-12-10 09:57:22 -08:00
fifo.c
file_table.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
file.c [PATCH] fdtable: Provide free_fdtable() wrapper 2006-12-22 08:55:50 -08:00
filesystems.c [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
fs-writeback.c Write back inode data pages even when the inode itself is locked 2007-01-26 12:53:20 -08:00
generic_acl.c
inode.c slab allocators: Remove SLAB_DEBUG_INITIAL flag 2007-05-07 12:12:57 -07:00
inotify_user.c [PATCH] inotify: read return val fix 2007-02-12 09:48:28 -08:00
inotify.c
internal.h
ioctl.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
ioprio.c [PATCH] pid: replace do/while_each_task_pid with do/while_each_pid_task 2007-02-12 09:48:32 -08:00
Kconfig Merge git://git.linux-nfs.org/pub/linux/nfs-2.6 2007-05-04 19:55:11 -07:00
Kconfig.binfmt blackfin architecture 2007-05-07 12:12:58 -07:00
libfs.c [PATCH] shmem and simple const super_operations 2007-03-05 07:57:51 -08:00
locks.c Merge branch 'server-cluster-locking-api' of git://linux-nfs.org/~bfields/linux 2007-05-07 12:34:24 -07:00
Makefile Remove JFFS (version 1), as scheduled. 2007-02-17 16:10:59 -05:00
mbcache.c [PATCH] slab: remove kmem_cache_t 2006-12-07 08:39:25 -08:00
mpage.c Factor outstanding I/O error handling 2007-05-08 11:14:57 -07:00
namei.c mm: make read_cache_page synchronous 2007-05-07 12:12:51 -07:00
namespace.c [PATCH] Transform kmem_cache_alloc()+memset(0) -> kmem_cache_zalloc(). 2007-02-11 10:51:27 -08:00
nfsctl.c
no-block.c
open.c [PATCH] fdtable: Make fdarray and fdsets equal in size 2006-12-10 09:57:22 -08:00
pipe.c [PATCH] AUDIT_FD_PAIR 2007-02-17 21:30:15 -05:00
pnode.c [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
pnode.h [PATCH] rename struct namespace to struct mnt_namespace 2006-12-08 08:28:51 -08:00
posix_acl.c
quota_v1.c
quota_v2.c
quota.c
read_write.c [PATCH] FS: speed up rw_verify_area() 2007-02-12 09:48:29 -08:00
read_write.h
readdir.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
select.c [PATCH] fdtable: Make fdarray and fdsets equal in size 2006-12-10 09:57:22 -08:00
seq_file.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
splice.c [PATCH] splice: partial write fix 2007-03-29 14:26:42 +02:00
stack.c [PATCH] fs/stack.c: Copy i_nlink after all other attributes are copied 2007-02-19 14:21:50 -08:00
stat.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00
super.c the overdue removal of the mount/umount uevents 2007-04-27 10:57:31 -07:00
sync.c [PATCH] Turn do_sync_file_range() into do_sync_mapping_range() 2007-04-26 15:02:26 -07:00
utimes.c
xattr_acl.c [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
xattr.c [PATCH] VFS: change struct file to use struct path 2006-12-08 08:28:41 -08:00