[PATCH v2 3/4] f2fs: enhance judgment conditions of GET_SEGNO

Zhiguo Niu
2024-02-07T02:02:11Z

NULL_SEGNO should also be returned when the blk_addr value is
out-of-bound main area even __is_valid_data_blkaddr return true.

For example, a 64MB partition with total 24 main segments has no
any free segments left, then a new wrtie request use get_new_segment
may get a out-of-bound segno 24 if CONFIG_F2FS_CHECK_FS is not enabled.
GET_SEGNO should also return NULL_SEGNO in this case rather than treating
is as valid segment.

Besides, if the caller of GET_SEGNO does not ensure blk_addr pass to
GET_SEGNO is valid, it should do sanity check about return value of
GET_SEGNO, avoid causing some unexpected problems later.

Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
---
fs/f2fs/file.c | 7 ++++++-
fs/f2fs/segment.c | 4 +++-
fs/f2fs/segment.h | 3 ++-
3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 23cd6a1..2cd3cd9 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -2985,9 +2985,14 @@ static int f2fs_ioc_flush_device(struct file *filp, unsigned long arg)
if (ret)
return ret;

- if (range.dev_num != 0)
+ if (range.dev_num != 0) {
dev_start_segno = GET_SEGNO(sbi, FDEV(range.dev_num).start_blk);
+ if (dev_start_segno == NULL_SEGNO)
+ return -EINVAL;
+ }
dev_end_segno = GET_SEGNO(sbi, FDEV(range.dev_num).end_blk);
+ if (dev_end_segno == NULL_SEGNO)
+ return -EINVAL;

start_segno = sm->last_victim[FLUSH_DEVICE];
if (start_segno < dev_start_segno || start_segno >= dev_end_segno)
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index f373ff7..6772ad4 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -2496,7 +2496,7 @@ void f2fs_invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr)
struct sit_info *sit_i = SIT_I(sbi);

f2fs_bug_on(sbi, addr == NULL_ADDR);
- if (addr == NEW_ADDR || addr == COMPRESS_ADDR)
+ if (segno == NULL_SEGNO)
return;

f2fs_invalidate_internal_cache(sbi, addr);
@@ -3708,6 +3708,8 @@ void f2fs_do_replace_block(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
unsigned char old_alloc_type;

segno = GET_SEGNO(sbi, new_blkaddr);
+ if (segno == NULL_SEGNO)
+ return;
se = get_seg_entry(sbi, segno);
type = se->type;

diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
index f2847f1..b0ea315 100644
--- a/fs/f2fs/segment.h
+++ b/fs/f2fs/segment.h
@@ -96,7 +96,8 @@ static inline void sanity_check_seg_type(struct f2fs_sb_info *sbi,
(GET_SEGOFF_FROM_SEG0(sbi, blk_addr) & ((sbi)->blocks_per_seg - 1))

#define GET_SEGNO(sbi, blk_addr) \
- ((!__is_valid_data_blkaddr(blk_addr)) ? \
+ ((!__is_valid_data_blkaddr(blk_addr) || \
+ !f2fs_is_valid_blkaddr(sbi, blk_addr, DATA_GENERIC)) ? \
NULL_SEGNO : GET_L2R_SEGNO(FREE_I(sbi), \
GET_SEGNO_FROM_SEG0(sbi, blk_addr)))
#define BLKS_PER_SEC(sbi) \
--
1.9.1