[LU-6876] integer overflow in ptlrpc_lprocfs_svc_req_history_start

• Type: Bug
• Resolution: Unresolved
• Priority: Minor
• Severity: 3
• Assignee: Liang Zhen (Inactive)
• Reporter: Oleg Drokin

Description

It looks like ptlrpc_lprocfs_svc_req_history_start has an integer oveflow shifting an integer value more than 32 bits away:

static void *
ptlrpc_lprocfs_svc_req_history_start(struct seq_file *s, loff_t *pos)
{
...
        int                             i;
...
                if (i > cpt) /* make up the lowest position for this CPT */
                        *pos = PTLRPC_REQ_CPT2POS(svc, i);
}

This produces following warning indicating the overflow is pretty real:

lustre/ptlrpc/lproc_ptlrpc.c:852 ptlrpc_lprocfs_svc_req_history_start() warn: should '(i) << (64 - (svc)->srv_cpt_bits)' be a 64 bit type?