[PATCH 5.18 713/879] f2fs: fix to do sanity check on total_data_blocks

Greg Kroah-Hartman
2022-06-08T01:29:25Z

From: Chao Yu <chao@kernel.org>

commit 6b8beca0edd32075a769bfe4178ca00c0dcd22a9 upstream.

As Yanming reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=215916

The kernel message is shown below:

kernel BUG at fs/f2fs/segment.c:2560!
Call Trace:
allocate_segment_by_default+0x228/0x440
f2fs_allocate_data_block+0x13d1/0x31f0
do_write_page+0x18d/0x710
f2fs_outplace_write_data+0x151/0x250
f2fs_do_write_data_page+0xef9/0x1980
move_data_page+0x6af/0xbc0
do_garbage_collect+0x312f/0x46f0
f2fs_gc+0x6b0/0x3bc0
f2fs_balance_fs+0x921/0x2260
f2fs_write_single_data_page+0x16be/0x2370
f2fs_write_cache_pages+0x428/0xd00
f2fs_write_data_pages+0x96e/0xd50
do_writepages+0x168/0x550
__writeback_single_inode+0x9f/0x870
writeback_sb_inodes+0x47d/0xb20
__writeback_inodes_wb+0xb2/0x200
wb_writeback+0x4bd/0x660
wb_workfn+0x5f3/0xab0
process_one_work+0x79f/0x13e0
worker_thread+0x89/0xf60
kthread+0x26a/0x300
ret_from_fork+0x22/0x30
RIP: 0010:new_curseg+0xe8d/0x15f0

The root cause is: ckpt.valid_block_count is inconsistent with SIT table,
stat info indicates filesystem has free blocks, but SIT table indicates
filesystem has no free segment.

So that during garbage colloection, it triggers panic when LFS allocator
fails to find free segment.

This patch tries to fix this issue by checking consistency in between
ckpt.valid_block_count and block accounted from SIT.

Cc: stable@vger.kernel.org
Reported-by: Ming Yan <yanming@tju.edu.cn>
Signed-off-by: Chao Yu <chao.yu@oppo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/f2fs/f2fs.h | 4 ++--
fs/f2fs/segment.c | 33 ++++++++++++++++++++++-----------
fs/f2fs/segment.h | 1 +
3 files changed, 25 insertions(+), 13 deletions(-)

--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1117,8 +1117,8 @@ enum count_type {
*/
#define PAGE_TYPE_OF_BIO(type) ((type) > META ? META : (type))
enum page_type {
- DATA,
- NODE,
+ DATA = 0,
+ NODE = 1, /* should not change this */
META,
NR_PAGE_TYPE,
META_FLUSH,
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -4460,7 +4460,7 @@ static int build_sit_entries(struct f2fs
unsigned int i, start, end;
unsigned int readed, start_blk = 0;
int err = 0;
- block_t total_node_blocks = 0;
+ block_t sit_valid_blocks[2] = {0, 0};

do {
readed = f2fs_ra_meta_pages(sbi, start_blk, BIO_MAX_VECS,
@@ -4485,8 +4485,8 @@ static int build_sit_entries(struct f2fs
if (err)
return err;
seg_info_from_raw_sit(se, &sit);
- if (IS_NODESEG(se->type))
- total_node_blocks += se->valid_blocks;
+
+ sit_valid_blocks[SE_PAGETYPE(se)] += se->valid_blocks;

if (f2fs_block_unit_discard(sbi)) {
/* build discard map only one time */
@@ -4526,15 +4526,15 @@ static int build_sit_entries(struct f2fs
sit = sit_in_journal(journal, i);

old_valid_blocks = se->valid_blocks;
- if (IS_NODESEG(se->type))
- total_node_blocks -= old_valid_blocks;
+
+ sit_valid_blocks[SE_PAGETYPE(se)] -= old_valid_blocks;

err = check_block_count(sbi, start, &sit);
if (err)
break;
seg_info_from_raw_sit(se, &sit);
- if (IS_NODESEG(se->type))
- total_node_blocks += se->valid_blocks;
+
+ sit_valid_blocks[SE_PAGETYPE(se)] += se->valid_blocks;

if (f2fs_block_unit_discard(sbi)) {
if (is_set_ckpt_flags(sbi, CP_TRIMMED_FLAG)) {
@@ -4556,13 +4556,24 @@ static int build_sit_entries(struct f2fs
}
up_read(&curseg->journal_rwsem);

- if (!err && total_node_blocks != valid_node_count(sbi)) {
+ if (err)
+ return err;
+
+ if (sit_valid_blocks[NODE] != valid_node_count(sbi)) {
f2fs_err(sbi, "SIT is corrupted node# %u vs %u",
- total_node_blocks, valid_node_count(sbi));
- err = -EFSCORRUPTED;
+ sit_valid_blocks[NODE], valid_node_count(sbi));
+ return -EFSCORRUPTED;
+ }
+
+ if (sit_valid_blocks[DATA] + sit_valid_blocks[NODE] >
+ valid_user_blocks(sbi)) {
+ f2fs_err(sbi, "SIT is corrupted data# %u %u vs %u",
+ sit_valid_blocks[DATA], sit_valid_blocks[NODE],
+ valid_user_blocks(sbi));
+ return -EFSCORRUPTED;
}

- return err;
+ return 0;
}

static void init_free_segmap(struct f2fs_sb_info *sbi)
--- a/fs/f2fs/segment.h
+++ b/fs/f2fs/segment.h
@@ -24,6 +24,7 @@

#define IS_DATASEG(t) ((t) <= CURSEG_COLD_DATA)
#define IS_NODESEG(t) ((t) >= CURSEG_HOT_NODE && (t) <= CURSEG_COLD_NODE)
+#define SE_PAGETYPE(se) ((IS_NODESEG((se)->type) ? NODE : DATA))

static inline void sanity_check_seg_type(struct f2fs_sb_info *sbi,
unsigned short seg_type)