linux/fs/xfs
Brian Foster 869ae85dae xfs: flush new eof page on truncate to avoid post-eof corruption
It is possible to expose non-zeroed post-EOF data in XFS if the new
EOF page is dirty, backed by an unwritten block and the truncate
happens to race with writeback. iomap_truncate_page() will not zero
the post-EOF portion of the page if the underlying block is
unwritten. The subsequent call to truncate_setsize() will, but
doesn't dirty the page. Therefore, if writeback happens to complete
after iomap_truncate_page() (so it still sees the unwritten block)
but before truncate_setsize(), the cached page becomes inconsistent
with the on-disk block. A mapped read after the associated page is
reclaimed or invalidated exposes non-zero post-EOF data.

For example, consider the following sequence when run on a kernel
modified to explicitly flush the new EOF page within the race
window:

$ xfs_io -fc "falloc 0 4k" -c fsync /mnt/file
$ xfs_io -c "pwrite 0 4k" -c "truncate 1k" /mnt/file
  ...
$ xfs_io -c "mmap 0 4k" -c "mread -v 1k 8" /mnt/file
00000400:  00 00 00 00 00 00 00 00  ........
$ umount /mnt/; mount <dev> /mnt/
$ xfs_io -c "mmap 0 4k" -c "mread -v 1k 8" /mnt/file
00000400:  cd cd cd cd cd cd cd cd  ........

Update xfs_setattr_size() to explicitly flush the new EOF page prior
to the page truncate to ensure iomap has the latest state of the
underlying block.

Fixes: 68a9f5e700 ("xfs: implement iomap based buffered write path")
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-11-04 08:52:46 -08:00
..
libxfs xfs: set xefi_discard when creating a deferred agfl free log intent item 2020-10-29 08:19:18 -07:00
scrub xfs: check dabtree node hash values when loading child blocks 2020-09-23 08:58:51 -07:00
Kconfig xfs: fix Kconfig asking about XFS_SUPPORT_V4 when XFS_FS=n 2020-10-16 15:34:28 -07:00
kmem.c xfs: remove kmem_realloc() 2020-09-06 18:05:51 -07:00
kmem.h xfs: Remove kmem_zalloc_large() 2020-09-15 20:52:41 -07:00
Makefile
mrlock.h
xfs_acl.c xfs: Remove kmem_zalloc_large() 2020-09-15 20:52:41 -07:00
xfs_acl.h
xfs_aops.c fs: Introduce i_blocks_per_page 2020-09-21 08:59:26 -07:00
xfs_aops.h
xfs_attr_inactive.c xfs: cleanup xfs_idestroy_fork 2020-05-19 09:40:59 -07:00
xfs_attr_list.c xfs: Convert xfs_attr_sf macros to inline functions 2020-09-15 20:52:42 -07:00
xfs_bio_io.c
xfs_bmap_item.c xfs: periodically relog deferred intent items 2020-10-07 08:40:28 -07:00
xfs_bmap_item.h xfs: refactor intent item RECOVERED flag into the log item 2020-05-08 08:50:01 -07:00
xfs_bmap_util.c xfs: fix fallocate functions when rtextsize is larger than 1 2020-10-21 09:05:19 -07:00
xfs_bmap_util.h
xfs_buf_item_recover.c xfs: fix finobt btree block recovery ordering 2020-09-30 07:28:52 -07:00
xfs_buf_item.c xfs: remove xlog_recover_iodone 2020-09-15 20:52:39 -07:00
xfs_buf_item.h xfs: move the buffer retry logic to xfs_buf.c 2020-09-15 20:52:38 -07:00
xfs_buf.c xfs: reuse _xfs_buf_read for re-reading the superblock 2020-09-15 20:52:39 -07:00
xfs_buf.h xfs: reuse _xfs_buf_read for re-reading the superblock 2020-09-15 20:52:39 -07:00
xfs_dir2_readdir.c xfs: move the fork format fields into struct xfs_ifork 2020-05-19 09:40:58 -07:00
xfs_discard.c
xfs_discard.h
xfs_dquot_item_recover.c xfs: rename the ondisk dquot d_flags to d_type 2020-07-28 20:24:14 -07:00
xfs_dquot_item.c xfs: stop using q_core.d_id in the quota code 2020-07-28 20:24:14 -07:00
xfs_dquot_item.h
xfs_dquot.c xfs: fix some comments 2020-09-25 11:34:07 -07:00
xfs_dquot.h xfs: refactor default quota grace period setting code 2020-09-15 20:52:40 -07:00
xfs_error.c
xfs_error.h
xfs_export.c xfs: delete duplicated words + other fixes 2020-08-05 08:49:58 -07:00
xfs_export.h
xfs_extent_busy.c
xfs_extent_busy.h
xfs_extfree_item.c xfs: periodically relog deferred intent items 2020-10-07 08:40:28 -07:00
xfs_extfree_item.h xfs: refactor intent item RECOVERED flag into the log item 2020-05-08 08:50:01 -07:00
xfs_file.c xfs: fix fallocate functions when rtextsize is larger than 1 2020-10-21 09:05:19 -07:00
xfs_filestream.c xfs: drop the obsolete comment on filestream locking 2020-09-25 11:34:08 -07:00
xfs_filestream.h
xfs_fsmap.c xfs: fix deadlock and streamline xfs_getfsmap performance 2020-10-07 08:40:29 -07:00
xfs_fsmap.h xfs: fix deadlock and streamline xfs_getfsmap performance 2020-10-07 08:40:29 -07:00
xfs_fsops.c
xfs_fsops.h
xfs_globals.c
xfs_health.c
xfs_icache.c xfs: Remove unneeded semicolon 2020-09-15 20:52:42 -07:00
xfs_icache.h xfs: remove SYNC_WAIT and SYNC_TRYLOCK 2020-07-14 08:47:33 -07:00
xfs_icreate_item.c xfs: Remove kmem_zone_zalloc() usage 2020-07-28 20:24:14 -07:00
xfs_icreate_item.h
xfs_inode_item_recover.c xfs: widen ondisk inode timestamps to deal with y2038+ 2020-09-15 20:52:41 -07:00
xfs_inode_item.c xfs: widen ondisk inode timestamps to deal with y2038+ 2020-09-15 20:52:41 -07:00
xfs_inode_item.h xfs: move the buffer retry logic to xfs_buf.c 2020-09-15 20:52:38 -07:00
xfs_inode.c xfs: drop extra transaction roll from inode extent truncate 2020-09-21 09:54:29 -07:00
xfs_inode.h xfs: widen ondisk inode timestamps to deal with y2038+ 2020-09-15 20:52:41 -07:00
xfs_ioctl32.c
xfs_ioctl32.h
xfs_ioctl.c xfs: fix deadlock and streamline xfs_getfsmap performance 2020-10-07 08:40:29 -07:00
xfs_ioctl.h
xfs_iomap.c xfs: delete duplicated words + other fixes 2020-08-05 08:49:58 -07:00
xfs_iomap.h
xfs_iops.c xfs: flush new eof page on truncate to avoid post-eof corruption 2020-11-04 08:52:46 -08:00
xfs_iops.h
xfs_itable.c xfs: move the fork format fields into struct xfs_ifork 2020-05-19 09:40:58 -07:00
xfs_itable.h
xfs_iwalk.c
xfs_iwalk.h
xfs_linux.h xfs: fix fallocate functions when rtextsize is larger than 1 2020-10-21 09:05:19 -07:00
xfs_log_cil.c xfs: delete duplicated words + other fixes 2020-08-05 08:49:58 -07:00
xfs_log_priv.h xfs: Modify xlog_ticket_alloc() to use kernel's MM API 2020-07-28 20:24:14 -07:00
xfs_log_recover.c xfs: cancel intents immediately if process_intents fails 2020-10-21 16:28:46 -07:00
xfs_log.c xfs: expose the log push threshold 2020-10-07 08:40:29 -07:00
xfs_log.h xfs: expose the log push threshold 2020-10-07 08:40:29 -07:00
xfs_message.c
xfs_message.h treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
xfs_mount.c xfs: remove xfs_getsb 2020-09-15 20:52:39 -07:00
xfs_mount.h xfs: remove xfs_getsb 2020-09-15 20:52:39 -07:00
xfs_mru_cache.c
xfs_mru_cache.h
xfs_ondisk.h xfs: Remove typedef xfs_attr_shortform_t 2020-09-15 20:52:42 -07:00
xfs_pnfs.c
xfs_pnfs.h
xfs_pwork.c block: remove the bd_queue field from struct block_device 2020-07-01 08:08:20 -06:00
xfs_pwork.h
xfs_qm_bhv.c xfs: rename XFS_DQ_{USER,GROUP,PROJ} to XFS_DQTYPE_* 2020-07-28 20:24:14 -07:00
xfs_qm_syscalls.c xfs: refactor default quota grace period setting code 2020-09-15 20:52:40 -07:00
xfs_qm.c xfs: do the ASSERT for the arguments O_{u,g,p}dqpp 2020-10-07 08:40:29 -07:00
xfs_qm.h xfs: refactor quota expiration timer modification 2020-09-15 20:52:40 -07:00
xfs_quota.h xfs: move the buffer retry logic to xfs_buf.c 2020-09-15 20:52:38 -07:00
xfs_quotaops.c xfs: create xfs_dqtype_t to represent quota types 2020-07-28 20:24:14 -07:00
xfs_refcount_item.c xfs: periodically relog deferred intent items 2020-10-07 08:40:28 -07:00
xfs_refcount_item.h xfs: refactor intent item RECOVERED flag into the log item 2020-05-08 08:50:01 -07:00
xfs_reflink.c xfs: delete duplicated words + other fixes 2020-08-05 08:49:58 -07:00
xfs_reflink.h xfs: move helpers that lock and unlock two inodes against userspace IO 2020-07-06 10:46:57 -07:00
xfs_rmap_item.c xfs: periodically relog deferred intent items 2020-10-07 08:40:28 -07:00
xfs_rmap_item.h xfs: refactor intent item RECOVERED flag into the log item 2020-05-08 08:50:01 -07:00
xfs_rtalloc.c xfs: annotate grabbing the realtime bitmap/summary locks in growfs 2020-10-13 08:41:31 -07:00
xfs_rtalloc.h
xfs_stats.c xfs: periodically relog deferred intent items 2020-10-07 08:40:28 -07:00
xfs_stats.h xfs: periodically relog deferred intent items 2020-10-07 08:40:28 -07:00
xfs_super.c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-10-24 12:26:05 -07:00
xfs_super.h
xfs_symlink.c xfs: move the fork format fields into struct xfs_ifork 2020-05-19 09:40:58 -07:00
xfs_symlink.h
xfs_sysctl.c xfs: remove deprecated sysctl options 2020-09-25 11:34:08 -07:00
xfs_sysctl.h
xfs_sysfs.c
xfs_sysfs.h xfs: Fix UBSAN null-ptr-deref in xfs_sysfs_init 2020-08-07 11:50:17 -07:00
xfs_trace.c
xfs_trace.h xfs: periodically relog deferred intent items 2020-10-07 08:40:28 -07:00
xfs_trans_ail.c xfs: delete duplicated words + other fixes 2020-08-05 08:49:58 -07:00
xfs_trans_buf.c xfs: simplify xfs_trans_getsb 2020-09-15 20:52:39 -07:00
xfs_trans_dquot.c xfs: fix the indent in xfs_trans_mod_dquot 2020-10-07 08:40:29 -07:00
xfs_trans_priv.h xfs: refactor adding recovered intent items to the log 2020-05-08 08:50:00 -07:00
xfs_trans.c xfs: do the assert for all the log done items in xfs_trans_cancel 2020-09-25 11:34:07 -07:00
xfs_trans.h xfs: periodically relog deferred intent items 2020-10-07 08:40:28 -07:00
xfs_xattr.c xfs: remove duplicate headers 2020-05-08 08:51:34 -07:00
xfs.h