[LU-13768] potential null pointer dereference in osd_statfs in osd-ldiskfs

• Type: Bug
• Resolution: Unresolved
• Priority: Minor
• Affects Version/s: Lustre 2.14.0
• Severity: 3
• Assignee: WC Triage
• Reporter: Oleg Drokin

Description

here's the code:

int osd_statfs(const struct lu_env *env, struct dt_device *d,
                struct obd_statfs *sfs, struct obd_statfs_info *info)
{
        struct osd_device *osd = osd_dt_dev(d);
        struct super_block *sb = osd_sb(osd);
        struct kstatfs *ksfs;
        __u64 reserved;
        int result = 0;

        if (unlikely(osd->od_mnt == NULL))
                return -EINPROGRESS;

the osd_sb is expanded as "osd->od_mnt->mnt_sb" so it does look like we either don't need the check for NUL below or should put the sb assignment after it.