fs: jfs: fix shift-out-of-bounds in dbDiscardAG

[ Upstream commit 25e70c6162 ]

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>
This commit is contained in:
Hoi Pok Wu 2022-10-25 23:20:45 +08:00 committed by Greg Kroah-Hartman
parent 78eba2778a
commit f8d4d0bac6
1 changed files with 5 additions and 0 deletions

View File

@ -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);