This is a note to let you know that I've just added the patch titled
f2fs: fix to do sanity check in update_sit_entry
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
f2fs-fix-to-do-sanity-check-in-update_sit_entry.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit f8770d25c5af27da52519e5ebb55241ef5059289
Author: Zhiguo Niu <zhiguo.niu@xxxxxxxxxx>
Date: Wed Feb 28 19:59:54 2024 +0800
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@xxxxxxxxxx>
Reviewed-by: Chao Yu <chao@xxxxxxxxxx>
Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 34090edc8ce25..6750cda692cc3 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -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;
@@ -2935,8 +2937,7 @@ 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);
+ update_sit_entry(sbi, old_blkaddr, -1);
if (!__has_curseg_space(sbi, type))
sit_i->s_ops->allocate_segment(sbi, type, false);
