From 6306ff39a7fcb7e9c59a00e6860b933b71a2ed3e Mon Sep 17 00:00:00 2001 From: Lizhi Xu Date: Mon, 9 Oct 2023 17:45:57 +0800 Subject: jfs: fix log->bdev_handle null ptr deref in lbmStartIO When sbi->flag is JFS_NOINTEGRITY in lmLogOpen(), log->bdev_handle can't be inited, so it value will be NULL. Therefore, add the "log ->no_integrity=1" judgment in lbmStartIO() to avoid such problems. Reported-and-tested-by: syzbot+23bc20037854bb335d59@syzkaller.appspotmail.com Signed-off-by: Lizhi Xu Link: https://lore.kernel.org/r/20231009094557.1398920-1-lizhi.xu@windriver.com Reviewed-by: Jan Kara Signed-off-by: Christian Brauner --- fs/jfs/jfs_logmgr.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'fs/jfs') diff --git a/fs/jfs/jfs_logmgr.c b/fs/jfs/jfs_logmgr.c index c911d838b8ec..cb6d1fda66a7 100644 --- a/fs/jfs/jfs_logmgr.c +++ b/fs/jfs/jfs_logmgr.c @@ -2110,10 +2110,14 @@ static void lbmStartIO(struct lbuf * bp) { struct bio *bio; struct jfs_log *log = bp->l_log; + struct block_device *bdev = NULL; jfs_info("lbmStartIO"); - bio = bio_alloc(log->bdev_handle->bdev, 1, REQ_OP_WRITE | REQ_SYNC, + if (!log->no_integrity) + bdev = log->bdev_handle->bdev; + + bio = bio_alloc(bdev, 1, REQ_OP_WRITE | REQ_SYNC, GFP_NOFS); bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9); __bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset); -- cgit