From: Hoi Pok Wu <wuhoipok@xxxxxxxxx>
[ Upstream commit 25e70c6162f207828dd405b432d8f2a98dbf7082 ]
This should be applied to most URSAN bugs found recently by syzbot,
by guarding the dbMount. As syzbot feeding rubbish into the bmap
descriptor.
Signed-off-by: Hoi Pok Wu <wuhoipok@xxxxxxxxx>
Signed-off-by: Dave Kleikamp <dave.kleikamp@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/jfs/jfs_dmap.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
index e1cbfbb60303..765838578a72 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -198,6 +198,11 @@ int dbMount(struct inode *ipbmap)
goto err_release_metapage;
}
+ if (((bmp->db_mapsize - 1) >> bmp->db_agl2size) > MAXAG) {
+ err = -EINVAL;
+ goto err_release_metapage;
+ }
+
for (i = 0; i < MAXAG; i++)
bmp->db_agfree[i] = le64_to_cpu(dbmp_le->dn_agfree[i]);
bmp->db_agsize = le64_to_cpu(dbmp_le->dn_agsize);
--
2.35.1
