Commit 3c2c864f authored Feb 28, 2024 by Zhiguo Niu Committed by Greg Kroah-Hartman Sep 04, 2024

f2fs: fix to do sanity check in update_sit_entry



[ Upstream commit 36959d18c3cf09b3c12157c6950e18652067de77 ]

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>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 5ae1493c

fs/f2fs/segment.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -2018,6 +2018,8 @@ 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;
		@@ -2935,7 +2937,6 @@ void 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);

		if (!__has_curseg_space(sbi, type))