f2fs: fix to do sanity check in update_sit_entry
Commit Message
If GET_SEGNO return NULL_SEGNO for some unecpected case,
update_sit_entry will access invalid memory address,
cause system crash. It is better to do sanity check about
GET_SEGNO just like update_segment_mtime & locate_dirty_segment.
Also remove some redundant judgment code.
Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
---
fs/f2fs/segment.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
Comments
On 2024/2/28 19:59, Zhiguo Niu wrote:
> If GET_SEGNO return NULL_SEGNO for some unecpected case,
> update_sit_entry will access invalid memory address,
> cause system crash. It is better to do sanity check about
> GET_SEGNO just like update_segment_mtime & locate_dirty_segment.
>
> Also remove some redundant judgment code.
>
> Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Thanks,
@@ -2407,6 +2407,8 @@ static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
#endif
segno = GET_SEGNO(sbi, blkaddr);
+ if (segno == NULL_SEGNO)
+ return;
se = get_seg_entry(sbi, segno);
new_vblocks = se->valid_blocks + del;
@@ -3504,8 +3506,7 @@ int f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
* since SSR needs latest valid block information.
*/
update_sit_entry(sbi, *new_blkaddr, 1);
- if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO)
- update_sit_entry(sbi, old_blkaddr, -1);
+ update_sit_entry(sbi, old_blkaddr, -1);
/*
* If the current segment is full, flush it out and replace it with a