Re: [syzbot] Re: KMSAN: uninit-value in gfs2_quota_init()

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Subject: Re: KMSAN: uninit-value in gfs2_quota_init()
Author: dmantipov@yandex.ru

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 7af08b57bcb9ebf78675c50069c54125c0a8b795

diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c
index dbf1aede744c..85736135bcf5 100644
--- a/fs/gfs2/dir.c
+++ b/fs/gfs2/dir.c
@@ -299,6 +299,10 @@ static int gfs2_dir_read_data(struct gfs2_inode *ip, __be64 *buf,
 				goto fail;
 			BUG_ON(extlen < 1);
 			bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
+			if (IS_ERR(bh)) {
+				error = PTR_ERR(bh);
+				goto fail;
+			}
 		} else {
 			error = gfs2_meta_read(ip->i_gl, dblock, DIO_WAIT, 0, &bh);
 			if (error)
diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c
index fea3efcc2f93..18957afed91a 100644
--- a/fs/gfs2/meta_io.c
+++ b/fs/gfs2/meta_io.c
@@ -532,7 +532,7 @@ struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen)
 	first_bh = gfs2_getbuf(gl, dblock, CREATE);
 
 	if (buffer_uptodate(first_bh))
-		goto out;
+		return first_bh;
 	bh_read_nowait(first_bh, REQ_META | REQ_PRIO);
 
 	dblock++;
@@ -546,11 +546,10 @@ struct buffer_head *gfs2_meta_ra(struct gfs2_glock *gl, u64 dblock, u32 extlen)
 		dblock++;
 		extlen--;
 		if (!buffer_locked(first_bh) && buffer_uptodate(first_bh))
-			goto out;
+			return first_bh;
 	}
 
 	wait_on_buffer(first_bh);
-out:
-	return first_bh;
+	return buffer_uptodate(first_bh) ? first_bh : ERR_PTR(-EIO);
 }
 
diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index 72b48f6f5561..d919edfb8dda 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -1427,8 +1427,10 @@ int gfs2_quota_init(struct gfs2_sbd *sdp)
 		}
 		error = -EIO;
 		bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
-		if (!bh)
+		if (IS_ERR(bh)) {
+			error = PTR_ERR(bh);
 			goto fail;
+		}
 		if (gfs2_metatype_check(sdp, bh, GFS2_METATYPE_QC))
 			goto fail_brelse;
 
diff --git a/fs/gfs2/recovery.c b/fs/gfs2/recovery.c
index f4fe7039f725..527353c36aa5 100644
--- a/fs/gfs2/recovery.c
+++ b/fs/gfs2/recovery.c
@@ -49,7 +49,7 @@ int gfs2_replay_read_block(struct gfs2_jdesc *jd, unsigned int blk,
 
 	*bh = gfs2_meta_ra(gl, dblock, extlen);
 
-	return error;
+	return IS_ERR(*bh) ? PTR_ERR(*bh) : 0;
 }
 
 int gfs2_revoke_add(struct gfs2_jdesc *jd, u64 blkno, unsigned int where)