linux-stable.git/fs/f2fs/data.c, branch linux-5.11.y

f2fs: compress: fix to assign cc.cluster_idx correctly

2021-05-19T08:29:53+00:00

[ Upstream commit 8bfbfb0ddd706b1ce2e89259ecc45f192c0ec2bf ]

In f2fs_destroy_compress_ctx(), after f2fs_destroy_compress_ctx(),
cc.cluster_idx will be cleared w/ NULL_CLUSTER, f2fs_cluster_blocks()
may check wrong cluster metadata, fix it.

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim 
Signed-off-by: Sasha Levin

f2fs: fix a wrong condition in __submit_bio

2021-03-04T11:14:21+00:00

[ Upstream commit 39f71b7e40e21805d6b15fc7750bdd9cab6a5010 ]

We should use !F2FS_IO_ALIGNED() to check and submit_io directly.

Fixes: 8223ecc456d0 ("f2fs: fix to add missing F2FS_IO_ALIGNED() condition")
Reviewed-by: Chao Yu 
Signed-off-by: Dehe Gu 
Signed-off-by: Ge Qiu 
Signed-off-by: Jaegeuk Kim 
Signed-off-by: Sasha Levin

f2fs: compress: fix potential deadlock

2021-03-04T11:14:17+00:00

[ Upstream commit 3afae09ffea5e08f523823be99a784675995d6bb ]

generic/269 reports a hangtask issue, the root cause is ABBA deadlock
described as below:

Thread A			Thread B
- down_write(&sbi->gc_lock) -- A
				- f2fs_write_data_pages
				 - lock all pages in cluster -- B
				 - f2fs_write_multi_pages
				  - f2fs_write_raw_pages
				   - f2fs_write_single_data_page
				    - f2fs_balance_fs
				     - down_write(&sbi->gc_lock) -- A
- f2fs_gc
 - do_garbage_collect
  - ra_data_block
   - pagecache_get_page -- B

To fix this, it needs to avoid calling f2fs_balance_fs() if there is
still cluster pages been locked in context of cluster writeback, so
instead, let's call f2fs_balance_fs() in the end of
f2fs_write_raw_pages() when all cluster pages were unlocked.

Fixes: 4c8ff7095bef ("f2fs: support data compression")
Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim 
Signed-off-by: Sasha Levin

f2fs: fix race of pending_pages in decompression

2020-12-08T23:39:14+00:00

I found out f2fs_free_dic() is invoked in a wrong timing, but
f2fs_verify_bio() still needed the dic info and it triggered the
below kernel panic. It has been caused by the race condition of
pending_pages value between decompression and verity logic, when
the same compression cluster had been split in different bios.
By split bios, f2fs_verify_bio() ended up with decreasing
pending_pages value before it is reset to nr_cpages by
f2fs_decompress_pages() and caused the kernel panic.

[ 4416.564763] Unable to handle kernel NULL pointer dereference
               at virtual address 0000000000000000
...
[ 4416.896016] Workqueue: fsverity_read_queue f2fs_verity_work
[ 4416.908515] pc : fsverity_verify_page+0x20/0x78
[ 4416.913721] lr : f2fs_verify_bio+0x11c/0x29c
[ 4416.913722] sp : ffffffc019533cd0
[ 4416.913723] x29: ffffffc019533cd0 x28: 0000000000000402
[ 4416.913724] x27: 0000000000000001 x26: 0000000000000100
[ 4416.913726] x25: 0000000000000001 x24: 0000000000000004
[ 4416.913727] x23: 0000000000001000 x22: 0000000000000000
[ 4416.913728] x21: 0000000000000000 x20: ffffffff2076f9c0
[ 4416.913729] x19: ffffffff2076f9c0 x18: ffffff8a32380c30
[ 4416.913731] x17: ffffffc01f966d97 x16: 0000000000000298
[ 4416.913732] x15: 0000000000000000 x14: 0000000000000000
[ 4416.913733] x13: f074faec89ffffff x12: 0000000000000000
[ 4416.913734] x11: 0000000000001000 x10: 0000000000001000
[ 4416.929176] x9 : ffffffff20d1f5c7 x8 : 0000000000000000
[ 4416.929178] x7 : 626d7464ff286b6b x6 : ffffffc019533ade
[ 4416.929179] x5 : 000000008049000e x4 : ffffffff2793e9e0
[ 4416.929180] x3 : 000000008049000e x2 : ffffff89ecfa74d0
[ 4416.929181] x1 : 0000000000000c40 x0 : ffffffff2076f9c0
[ 4416.929184] Call trace:
[ 4416.929187]  fsverity_verify_page+0x20/0x78
[ 4416.929189]  f2fs_verify_bio+0x11c/0x29c
[ 4416.929192]  f2fs_verity_work+0x58/0x84
[ 4417.050667]  process_one_work+0x270/0x47c
[ 4417.055354]  worker_thread+0x27c/0x4d8
[ 4417.059784]  kthread+0x13c/0x320
[ 4417.063693]  ret_from_fork+0x10/0x18

Chao pointed this can happen by the below race condition.

Thread A        f2fs_post_read_wq          fsverity_wq
- f2fs_read_multi_pages()
  - f2fs_alloc_dic
   - dic->pending_pages = 2
   - submit_bio()
   - submit_bio()
               - f2fs_post_read_work() handle first bio
                - f2fs_decompress_work()
                 - __read_end_io()
                  - f2fs_decompress_pages()
                   - dic->pending_pages--
                - enqueue f2fs_verity_work()
                                           - f2fs_verity_work() handle first bio
                                            - f2fs_verify_bio()
                                             - dic->pending_pages--
               - f2fs_post_read_work() handle second bio
                - f2fs_decompress_work()
                - enqueue f2fs_verity_work()
                                            - f2fs_verify_pages()
                                            - f2fs_free_dic()

                                          - f2fs_verity_work() handle second bio
                                           - f2fs_verfy_bio()
                                                 - use-after-free on dic

Signed-off-by: Daeho Jeong 
Signed-off-by: Jaegeuk Kim

f2fs: introduce max_io_bytes, a sysfs entry, to limit bio size

2020-12-07T16:41:25+00:00

This patch adds max_io_bytes to limit bio size when f2fs tries to merge
consecutive IOs. This can give a testing point to split out bios and check
end_io handles those bios correctly. This is used to capture a recent bug
on the decompression and fsverity flow.

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

f2fs: add compress_mode mount option

2020-12-03T08:11:57+00:00

We will add a new "compress_mode" mount option to control file
compression mode. This supports "fs" and "user". In "fs" mode (default),
f2fs does automatic compression on the compression enabled files.
In "user" mode, f2fs disables the automaic compression and gives the
user discretion of choosing the target file and the timing. It means
the user can do manual compression/decompression on the compression
enabled files using ioctls.

Signed-off-by: Daeho Jeong 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: remove buffer_head which has 32bits limit

2020-12-03T06:00:23+00:00

This patch removes buffer_head dependency when getting block addresses.
Light reported there's a 32bit issue in f2fs_fiemap where map_bh.b_size is
32bits while len is 64bits given by user. This will give wrong length to
f2fs_map_block.

Reported-by: Light Hsieh 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: fix wrong block count instead of bytes

2020-12-03T06:00:22+00:00

We should convert cur_lblock, a block count, to bytes for len.

Fixes: af4b6b8edf6a ("f2fs: introduce check_swap_activate_fast()")
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: use new conversion functions between blks and bytes

2020-12-03T06:00:22+00:00

This patch cleans up blks and bytes conversions.

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

f2fs: rename logical_to_blk and blk_to_logical

2020-12-03T06:00:22+00:00

This patch renames two functions like below having u64.
 - logical_to_blk to bytes_to_blks
 - blk_to_logical to blks_to_bytes

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