rdma/utils: fix some analyzer warnings

Add error checks for cases where analyzer thinks it is possible
to us a possibly NULL value.

utils.c: In function ‘get_port_from_argv’:
utils.c:76:17: warning: use of NULL where non-null expected [CWE-476] [-Wanalyzer-null-argument]
   76 |         slash = strchr(rd_argv(rd), '/');
      |                 ^~~~~~~~~~~~~~~~~~~~~~~~
  ‘get_port_from_argv’: events 1-2
    |
    |   68 | static int get_port_from_argv(struct rd *rd, uint32_t *port,
    |      |            ^~~~~~~~~~~~~~~~~~
    |      |            |
    |      |            (1) entry to ‘get_port_from_argv’
    |......
    |   76 |         slash = strchr(rd_argv(rd), '/');
    |      |                        ~
    |      |                        |
    |      |                        (2) inlined call to ‘rd_argv’ from ‘get_port_from_argv’
    |
    +--> ‘rd_argv’: event 3
           |
           |   18 |         if (!rd_argc(rd))
           |      |            ^
           |      |            |
           |      |            (3) following ‘true’ branch...
           |
    <------+
    |
  ‘get_port_from_argv’: events 4-5
    |
    |   76 |         slash = strchr(rd_argv(rd), '/');
    |      |                 ^~~~~~~~~~~~~~~~~~~~~~~~
    |      |                 |
    |      |                 (4) ...to here
    |      |                 (5) argument 1 (‘<unknown>’) NULL where non-null expected
    |
In file included from rdma.h:10,
                 from utils.c:7:
/usr/include/string.h:246:14: note: argument 1 of ‘strchr’ must be non-null
  246 | extern char *strchr (const char *__s, int __c)
      |              ^~~~~~

Fixes: 40df8263a0f0 ("rdma: Add dev object")
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>

diff --git a/rdma/utils.c b/rdma/utils.c
index 21177b565bf1e64d0eef4a40c03f1997fd3c9746..a33ff420f8cba861c1995bf3c5ea79a76764d3dd 100644 (file)
--- a/rdma/utils.c
+++ b/rdma/utils.c
@@ -75,6 +75,13 @@ static int get_port_from_argv(struct rd *rd, uint32_t *port,
 
        slash = strchr(rd_argv(rd), '/');
        /* if no port found, return 0 */
+       if (slash == NULL) {
+               if (strict_port)
+                       return -EINVAL;
+               else
+                       return 0;
+       }
+
        if (slash++) {
                if (*slash == '-') {
                        if (strict_port)
@@ -747,6 +754,9 @@ struct dev_map *dev_map_lookup(struct rd *rd, bool allow_port_index)
                return NULL;
 
        dev_name = strdup(rd_argv(rd));
+       if (!dev_name)
+               return NULL;
+
        if (allow_port_index) {
                slash = strrchr(dev_name, '/');
                if (slash)