From: Hoi Pok Wu wuhoipok@gmail.com
[ 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@gmail.com Signed-off-by: Dave Kleikamp dave.kleikamp@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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 a46fa0f3db57..0ca1ad2610df 100644 --- a/fs/jfs/jfs_dmap.c +++ b/fs/jfs/jfs_dmap.c @@ -211,6 +211,11 @@ 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);