Hi, Dan, On Mon, Feb 15, 2021 at 1:44 PM Dan Carpenter <dan.carpenter(a)oracle.com&gt; wrote: > > tree: https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma.git wip/jgg-for-next > head: c88b31c46cefe50f524a1ad3deaf1599bc9ee2e6 > commit: f0751419d3a15fb06d9b7d9435312472c3cb122d [198/203] RDMA/rtrs: Only allow addition of path to an already established session > config: ia64-randconfig-m031-20210209 (attached as .config) > compiler: ia64-linux-gcc (GCC) 9.3.0 > > If you fix the issue, kindly add following tag as appropriate > Reported-by: kernel test robot <lkp(a)intel.com&gt; > Reported-by: Dan Carpenter <dan.carpenter(a)oracle.com&gt; > > smatch warnings: > drivers/infiniband/ulp/rtrs/rtrs-srv.c:1805 rtrs_rdma_connect() warn: passing zero to 'PTR_ERR' > > vim +/PTR_ERR +1805 drivers/infiniband/ulp/rtrs/rtrs-srv.c > > 9cb837480424e7 Jack Wang 2020-05-11 1760 static int rtrs_rdma_connect(struct rdma_cm_id *cm_id, > 9cb837480424e7 Jack Wang 2020-05-11 1761 const struct rtrs_msg_conn_req *msg, > 9cb837480424e7 Jack Wang 2020-05-11 1762 size_t len) > 9cb837480424e7 Jack Wang 2020-05-11 1763 { > 9cb837480424e7 Jack Wang 2020-05-11 1764 struct rtrs_srv_ctx *ctx = cm_id->context; > 9cb837480424e7 Jack Wang 2020-05-11 1765 struct rtrs_srv_sess *sess; > 9cb837480424e7 Jack Wang 2020-05-11 1766 struct rtrs_srv *srv; > 9cb837480424e7 Jack Wang 2020-05-11 1767 > 9cb837480424e7 Jack Wang 2020-05-11 1768 u16 version, con_num, cid; > 9cb837480424e7 Jack Wang 2020-05-11 1769 u16 recon_cnt; > 9cb837480424e7 Jack Wang 2020-05-11 1770 int err; > 9cb837480424e7 Jack Wang 2020-05-11 1771 > 9cb837480424e7 Jack Wang 2020-05-11 1772 if (len < sizeof(*msg)) { > 9cb837480424e7 Jack Wang 2020-05-11 1773 pr_err("Invalid RTRS connection request\n"); > 9cb837480424e7 Jack Wang 2020-05-11 1774 goto reject_w_econnreset; > 9cb837480424e7 Jack Wang 2020-05-11 1775 } > 9cb837480424e7 Jack Wang 2020-05-11 1776 if (le16_to_cpu(msg->magic) != RTRS_MAGIC) { > 9cb837480424e7 Jack Wang 2020-05-11 1777 pr_err("Invalid RTRS magic\n"); > 9cb837480424e7 Jack Wang 2020-05-11 1778 goto reject_w_econnreset; > 9cb837480424e7 Jack Wang 2020-05-11 1779 } > 9cb837480424e7 Jack Wang 2020-05-11 1780 version = le16_to_cpu(msg->version); > 9cb837480424e7 Jack Wang 2020-05-11 1781 if (version >> 8 != RTRS_PROTO_VER_MAJOR) { > 9cb837480424e7 Jack Wang 2020-05-11 1782 pr_err("Unsupported major RTRS version: %d, expected %d\n", > 9cb837480424e7 Jack Wang 2020-05-11 1783 version >> 8, RTRS_PROTO_VER_MAJOR); > 9cb837480424e7 Jack Wang 2020-05-11 1784 goto reject_w_econnreset; > 9cb837480424e7 Jack Wang 2020-05-11 1785 } > 9cb837480424e7 Jack Wang 2020-05-11 1786 con_num = le16_to_cpu(msg->cid_num); > 9cb837480424e7 Jack Wang 2020-05-11 1787 if (con_num > 4096) { > 9cb837480424e7 Jack Wang 2020-05-11 1788 /* Sanity check */ > 9cb837480424e7 Jack Wang 2020-05-11 1789 pr_err("Too many connections requested: %d\n", con_num); > 9cb837480424e7 Jack Wang 2020-05-11 1790 goto reject_w_econnreset; > 9cb837480424e7 Jack Wang 2020-05-11 1791 } > 9cb837480424e7 Jack Wang 2020-05-11 1792 cid = le16_to_cpu(msg->cid); > 9cb837480424e7 Jack Wang 2020-05-11 1793 if (cid >= con_num) { > 9cb837480424e7 Jack Wang 2020-05-11 1794 /* Sanity check */ > 9cb837480424e7 Jack Wang 2020-05-11 1795 pr_err("Incorrect cid: %d >= %d\n", cid, con_num); > 9cb837480424e7 Jack Wang 2020-05-11 1796 goto reject_w_econnreset; > 9cb837480424e7 Jack Wang 2020-05-11 1797 } > 9cb837480424e7 Jack Wang 2020-05-11 1798 recon_cnt = le16_to_cpu(msg->recon_cnt); > f0751419d3a15f Md Haris Iqbal 2021-02-12 1799 srv = get_or_create_srv(ctx, &msg->paths_uuid, msg->first_conn); > d715ff8acbd587 Guoqing Jiang 2020-10-23 1800 /* > d715ff8acbd587 Guoqing Jiang 2020-10-23 1801 * "refcount == 0" happens if a previous thread calls get_or_create_srv > d715ff8acbd587 Guoqing Jiang 2020-10-23 1802 * allocate srv, but chunks of srv are not allocated yet. > d715ff8acbd587 Guoqing Jiang 2020-10-23 1803 */ > f0751419d3a15f Md Haris Iqbal 2021-02-12 1804 if (IS_ERR(srv) || refcount_read(&srv->refcount) == 0) { > f0751419d3a15f Md Haris Iqbal 2021-02-12 @1805 err = PTR_ERR(srv); > > It's not 100% clear to me that an error code is required when > refcount_read() is zero. Maybe "err = 0;" is okay in that situation? I don't see how srv can be zero