[PATCH AUTOSEL 5.10 12/24] gfs2: Fix inode height consistency check

Sasha Levin
2023-05-04T20:02:53Z

From: Andreas Gruenbacher <agruenba@redhat.com>

[ Upstream commit cfcdb5bad34f600aed7613c3c1a5e618111f77b7 ]

The maximum allowed height of an inode's metadata tree depends on the
filesystem block size; it is lower for bigger-block filesystems. When
reading in an inode, make sure that the height doesn't exceed the
maximum allowed height.

Arrays like sd_heightsize are sized to be big enough for any filesystem
block size; they will often be slightly bigger than what's needed for a
specific filesystem.

Reported-by: syzbot+45d4691b1ed3c48eba05@syzkaller.appspotmail.com
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/gfs2/glops.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index db28c240dae35..87f8110884663 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -405,6 +405,7 @@ static int inode_go_demote_ok(const struct gfs2_glock *gl)

static int gfs2_dinode_in(struct gfs2_inode *ip, const void *buf)
{
+ struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
const struct gfs2_dinode *str = buf;
struct timespec64 atime;
u16 height, depth;
@@ -444,7 +445,7 @@ static int gfs2_dinode_in(struct gfs2_inode *ip, const void *buf)
/* i_diskflags and i_eattr must be set before gfs2_set_inode_flags() */
gfs2_set_inode_flags(&ip->i_inode);
height = be16_to_cpu(str->di_height);
- if (unlikely(height > GFS2_MAX_META_HEIGHT))
+ if (unlikely(height > sdp->sd_max_height))
goto corrupt;
ip->i_height = (u8)height;

--
2.39.2