linux.git/fs/f2fs/segment.c, branch v5.3

f2fs: avoid out-of-range memory access

2019-07-11T01:13:53+00:00

blkoff_off might over 512 due to fs corrupt or security
vulnerability. That should be checked before being using.

Use ENTRIES_IN_SUM to protect invalid value in cur_data_blkoff.

Signed-off-by: Ocean Chen 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: fix to avoid long latency during umount

2019-07-11T01:13:53+00:00

In umount, we give an constand time to handle pending discard, previously,
in __issue_discard_cmd() we missed to check timeout condition in loop,
result in delaying long time, fix it.

Signed-off-by: Heng Xiao 
[Chao Yu: add commit message]
Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: use generic EFSBADCRC/EFSCORRUPTED

2019-07-02T22:40:41+00:00

f2fs uses EFAULT as error number to indicate filesystem is corrupted
all the time, but generic filesystems use EUCLEAN for such condition,
we need to change to follow others.

This patch adds two new macros as below to wrap more generic error
code macros, and spread them in code.

EFSBADCRC	EBADMSG		/* Bad CRC detected */
EFSCORRUPTED	EUCLEAN		/* Filesystem is corrupted */

Reported-by: Pavel Machek 
Signed-off-by: Chao Yu 
Acked-by: Pavel Machek 
Signed-off-by: Jaegeuk Kim

f2fs: print kernel message if filesystem is inconsistent

2019-07-02T22:40:41+00:00

As Pavel reported, once we detect filesystem inconsistency in
f2fs_inplace_write_data(), it will be better to print kernel message as
we did in other places.

Reported-by: Pavel Machek 
Signed-off-by: Chao Yu 
Acked-by: Pavel Machek 
Signed-off-by: Jaegeuk Kim

f2fs: introduce f2fs_ macros to wrap f2fs_printk()

2019-07-02T22:40:40+00:00

- Add and use f2fs_ macros
- Convert f2fs_msg to f2fs_printk
- Remove level from f2fs_printk and embed the level in the format
- Coalesce formats and align multi-line arguments
- Remove unnecessary duplicate extern f2fs_msg f2fs.h

Signed-off-by: Joe Perches 
Signed-off-by: Chao Yu 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: ioctl for removing a range from F2FS

2019-07-02T22:39:24+00:00

This ioctl shrinks a given length (aligned to sections) from end of the
main area. Any cursegs and valid blocks will be moved out before
invalidating the range.

This feature can be used for adjusting partition sizes online.

History of the patch:

Sahitya Tummala:
 - Add this ioctl for f2fs_compat_ioctl() as well.
 - Fix debugfs status to reflect the online resize changes.
 - Fix potential race between online resize path and allocate new data
   block path or gc path.

Others:
 - Rename some identifiers.
 - Add some error handling branches.
 - Clear sbi->next_victim_seg[BG_GC/FG_GC] in shrinking range.
 - Implement this interface as ext4's, and change the parameter from shrunk
bytes to new block count of F2FS.
 - During resizing, force to empty sit_journal and forbid adding new
   entries to it, in order to avoid invalid segno in journal after resize.
 - Reduce sbi->user_block_count before resize starts.
 - Commit the updated superblock first, and then update in-memory metadata
   only when the former succeeds.
 - Target block count must align to sections.
 - Write checkpoint before and after committing the new superblock, w/o
CP_FSCK_FLAG respectively, so that the FS can be fixed by fsck even if
resize fails after the new superblock is committed.
 - In free_segment_range(), reduce granularity of gc_mutex.
 - Add protection on curseg migration.
 - Add freeze_bdev() and thaw_bdev() for resize fs.
 - Remove CUR_MAIN_SECS and use MAIN_SECS directly for allocation.
 - Recover super_block and FS metadata when resize fails.
 - No need to clear CP_FSCK_FLAG in update_ckpt_flags().
 - Clean up the sb and fs metadata update functions for resize_fs.

Geert Uytterhoeven:
 - Use div_u64*() for 64-bit divisions

Arnd Bergmann:
 - Not all architectures support get_user() with a 64-bit argument:
    ERROR: "__get_user_bad" [fs/f2fs/f2fs.ko] undefined!
    Use copy_from_user() here, this will always work.

Signed-off-by: Qiuyang Sun 
Signed-off-by: Chao Yu 
Signed-off-by: Sahitya Tummala 
Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Arnd Bergmann 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: Add option to limit required GC for checkpoint=disable

2019-06-03T20:27:48+00:00

This extends the checkpoint option to allow checkpoint=disable:%u[%]
This allows you to specify what how much of the disk you are willing
to lose access to while mounting with checkpoint=disable. If the amount
lost would be higher, the mount will return -EAGAIN. This can be given
as a percent of total space, or in blocks.

Currently, we need to run garbage collection until the amount of holes
is smaller than the OVP space. With the new option, f2fs can mark
space as unusable up front instead of requiring garbage collection until
the number of holes is small enough.

Signed-off-by: Daniel Rosenberg 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: Lower threshold for disable_cp_again

2019-06-03T20:27:47+00:00

The existing threshold for allowable holes at checkpoint=disable time is
too high. The OVP space contains reserved segments, which are always in
the form of free segments. These must be subtracted from the OVP value.

The current threshold is meant to be the maximum value of holes of a
single type we can have and still guarantee that we can fill the disk
without failing to find space for a block of a given type.

If the disk is full, ignoring current reserved, which only helps us,
the amount of unused blocks is equal to the OVP area. Of that, there
are reserved segments, which must be free segments, and the rest of the
ovp area, which can come from either free segments or holes. The maximum
possible amount of holes is OVP-reserved.

Now, consider the disk when mounting with checkpoint=disable.
We must be able to fill all available free space with either data or
node blocks. When we start with checkpoint=disable, holes are locked to
their current type. Say we have H of one type of hole, and H+X of the
other. We can fill H of that space with arbitrary typed blocks via SSR.
For the remaining H+X blocks, we may not have any of a given block type
left at all. For instance, if we were to fill the disk entirely with
blocks of the type with fewer holes, the H+X blocks of the opposite type
would not be used. If H+X > OVP-reserved, there would be more holes than
could possibly exist, and we would have failed to find a suitable block
earlier on, leading to a crash in update_sit_entry.

If H+X <= OVP-reserved, then the holes end up effectively masked by the OVP
region in this case.

Signed-off-by: Daniel Rosenberg 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: add error prints for debugging mount failure

2019-05-30T16:13:54+00:00

Add error prints to get more details on the mount failure.

Signed-off-by: Sahitya Tummala 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: fix to do sanity check on segment bitmap of LFS curseg

2019-05-30T16:13:49+00:00

As Jungyeon Reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=203233

- Reproduces
gcc poc_13.c
./run.sh f2fs

- Kernel messages
 F2FS-fs (sdb): Bitmap was wrongly set, blk:4608
 kernel BUG at fs/f2fs/segment.c:2133!
 RIP: 0010:update_sit_entry+0x35d/0x3e0
 Call Trace:
  f2fs_allocate_data_block+0x16c/0x5a0
  do_write_page+0x57/0x100
  f2fs_do_write_node_page+0x33/0xa0
  __write_node_page+0x270/0x4e0
  f2fs_sync_node_pages+0x5df/0x670
  f2fs_write_checkpoint+0x364/0x13a0
  f2fs_sync_fs+0xa3/0x130
  f2fs_do_sync_file+0x1a6/0x810
  do_fsync+0x33/0x60
  __x64_sys_fsync+0xb/0x10
  do_syscall_64+0x43/0x110
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

The testcase fails because that, in fuzzed image, current segment was
allocated with LFS type, its .next_blkoff should point to an unused
block address, but actually, its bitmap shows it's not. So during
allocation, f2fs crash when setting bitmap.

Introducing sanity_check_curseg() to check such inconsistence of
current in-used segment.

Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim