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

[Zhiguo Niu]

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@xxxxxxxxxx>
---
 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