From: Abdun Nihaal abdun.nihaal@gmail.com
[ Upstream commit 557d19675a470bb0a98beccec38c5dc3735c20fa ]
Syzbot reports an out of bound access in ntfs_trim_fs. The cause of this is using a loop termination condition that compares window index (iw) with wnd->nbits instead of wnd->nwnd, due to which the index used for wnd->free_bits exceeds the size of the array allocated.
Fix the loop condition.
Fixes: 3f3b442b5ad2 ("fs/ntfs3: Add bitmap") Link: https://syzkaller.appspot.com/bug?extid=b892240eac461e488d51 Reported-by: syzbot+b892240eac461e488d51@syzkaller.appspotmail.com Signed-off-by: Abdun Nihaal abdun.nihaal@gmail.com Signed-off-by: Konstantin Komarov almaz.alexandrovich@paragon-software.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ntfs3/bitmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/ntfs3/bitmap.c b/fs/ntfs3/bitmap.c index 5d44ceac855b..087282cb130b 100644 --- a/fs/ntfs3/bitmap.c +++ b/fs/ntfs3/bitmap.c @@ -1424,7 +1424,7 @@ int ntfs_trim_fs(struct ntfs_sb_info *sbi, struct fstrim_range *range)
down_read_nested(&wnd->rw_lock, BITMAP_MUTEX_CLUSTERS);
- for (; iw < wnd->nbits; iw++, wbit = 0) { + for (; iw < wnd->nwnd; iw++, wbit = 0) { CLST lcn_wnd = iw * wbits; struct buffer_head *bh;